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Our objectives were to assess the effects of eicosapentaenoic (EPA) and docosahexaenoic acids (DHA) supplementation to pregnant ewes during the first third of gestation on their offspring’s liver, adipose, and muscle tissues fatty acid (FA) profile and liver mRNA expression after a finishing period receiving diets with different FA profiles. Twenty-four post-weaning lambs, blocked by sex and body weight, were used in a 2×2 factorial arrangement of treatments. The first factor was dam supplementation (DS) in the first third of gestation with 1.61% of Ca salts of palm fatty acid distillate (PFAD) or Ca salts enriched with EPA-DHA. Ewes were exposed to rams with marking paint harnesses during the breeding. Ewes started DS at the day of mating, considered day one of conception. Twenty-eight days after mating, ultrasonography was used to confirm pregnancy, and non-pregnant ewes were removed from the groups. After weaning, the offspring lambs were supplemented (LS, second main factor) with two different FA sources (1.48% of PFAD or 1.48% of EPA-DHA) during the growing and fattening phase. Lambs were fed the LS diet for 56 days and sent to slaughter, where the liver, muscle, and adipose tissue samples were collected for FA analysis. Liver samples were collected for relative mRNA expression for genes associated with FA transport and metabolism. The data were analyzed as a mixed model in SAS (9.4). In the liver, the amount of C20:5 and C22:6 (P < 0.01) increased in lambs with LS-EPA-DHA, while some C18:1 cis FA isomers were greater in the lambs from DS-PFAD. In muscle, amounts of C22:1, C20:5 and C22:5 increased (P < 0.05) in lambs born from DS-EPA-DHA. The adipose tissue amounts of C20:5, C22:5, C22:6 were greater (P < 0.01) in lambs from LS-EPA-DHA. Interactions (DS×LS; P < 0.05) were observed for DNMT3β, FABP-1, FABP-5, SCD, and SREBP-1; having greater mRNA expression in liver tissue of LS-EPA-DHA, DS-PFAD and LS-PFAD, DS-EPA-DHA lambs compared with the lambs in the other two treatments. Liver ELOVL2 mRNA relative expression (P < 0.03) was greater in the offspring of DS-PFAD. Relative mRNA expression (P < 0.05) of GLUT1, IGF-1, LPL, and PPARγ increased in the liver from LS-EPA-DHA lambs. Dam supplementation during early gestation using with differnet FA sources changed the lipid FA profile in MT, LT and SAT during the finishing period depending on the tissue and type of FA source administered during the growing phase. more...

We evaluate the effect of the weaning strategy (WS; early, 130 ± 21 d vs. normal, 187 ± 20 d) and backgrounding management (BGM) on growth, carcass characteristics, and relative mRNA expression in the longissimus muscle (LM) of beef steers. One hundred and twenty Angus × SimAngus-crossbred steers (body weight (BW) = 130 ± 11.2 kg) were used in a randomized complete block design. Steers, blocked by age and BW, were randomly assigned to one treatment (2 × 2 factorial). Treatments consisted of early weaned (EW) or normal weaned (NW) steers subsequently backgrounded (BG) on either a forage-based (FB) or concentrates-based (CB) diet. The EW steers (d 0) were ad libitum-fed a grain-based diet for 49 d until nursing calves were NW. Steers were ad libitum-fed either a FB diet for 214 d or a CB diet for 95 d afterward. Steers were finished on a high-grain diet until harvested at an estimated constant 12th-rib fat thickness (1.5 cm). Expression of mRNA in the LM was measured over time. Data were analyzed using PROC MIXED in SAS. The EW steers were heavier (P ˂ 0.01) at the beginning of the backgrounding and finishing period. When the finishing phase began, steers FB were heavier (P ˂ 0.01) than CB steers. There was a tendency for a WS × BGM interaction (P = 0.08) for final BW, where NW-FB steers were heavier than the steers on the other three treatments, which do not differ between them. In the finishing phase, steers BG on a FB diet had greater dry matter intake and average daily gain, but lower gain-to-feed ratio (P ˂ 0.01). There was a WS × BGM interaction (P = 0.03) for days on feed (DOF) in the finishing diet, where backgrounding steers in a FB diet decreased DOF required to reach the harvesting target among EW steers, but not within NW steers. No interactions or treatment effects (P ≥ 0.17) were detected for marbling score (MS). For ZFP423, EW steers showed a greater mRNA expression on d 112 and a lower expression on d 255 than NW steers (P ˂ 0.01). In d 57, steers BG on a CB diet presented a greater delta-like homolog 1 mRNA expression than steers BG on a FB diet, whereas in d 255, this was inverted (P ˂ 0.01). For CCAAT/enhancer binding protein D (C/EBPD) mRNA expression, a tendency for a WS × BGM interaction was observed (P = 0.06), where a greater expression of C/EBPD was observed in steers BG on a FB diet among EW steers, but not within NW steers. In this study, early grain feeding followed by different BGM does not support MS improvements of beef carcasses. more...

Objectives Our objective was to evaluate the effects of incremental inclusion rates of dietary soybean hulls (SH) on finishing performance, roughage intake (RI), and carcass characteristics in feedlot cattle fed free-choice hay. Materials and Methods Angus × SimAngus-crossbred heifers (n = 60) and steers (n = 54) were stratified by sex and BW and assigned into 12 pens. Treatment 1 contained 5% soybean hulls, 70% ground corn (GC), 15% distiller grains, and 10% mineral supplement. Treatments 2 and 3 included an additional 5% and 10% SH in place of GC, respectively. Data were analyzed as a randomized complete block (BW) design using 2 different multiple linear regression analyses considering (1) the effects of total NDF intake (TNDFI), roughage NDF intake (RNDFI), and RI variability on growth and carcass characteristics and (2) the effects of concentrate NDF intake (CNDFI) and RI variability on RI. Results and Discussion There were treatment × sex interactions (P ≤ 0.03) for DMI, final BW and RI. In heifers, substituting 15% GC with SH increased DMI at the expense of RI. Substituting GC with SH did not affect DMI of steers, but feeding increasing SH decreased final BW. Average daily gain and DMI were negatively associated (P ≤ 0.05) with TNDFI and RNDFI. The RI was negatively (P ≤ 0.05) associated with CNDFI. The LM area of steer carcasses was negatively associated (P Implications and Applications Despite differential responses to dietary treatments between steers and heifers, cost effectiveness of replacing a small portion of corn with SH will depend on the difference of feed costs. more...

To evaluate the effect of supplementing beef cattle with a ruminal probiotic consisting of native rumen microbes (NRM; Chordicoccus furentiruminis, Prevotella albensis, and Succinivibrio dextrinosolvens) on methane (CH4) emissions, growth performance, carcass characteristics, and plasma metabolites, Angus × SimAngus-crossbred steers (n = 32; 8 per pen) and heifers (n = 48; 12 per pen) with an initial body weight (BW) of 353 ± 64 kg were used in randomized complete block design. Cattle were blocked by sex and BW and randomly assigned to 1 of 2 treatments (2 pens per treatment). Treatments consisted of diets offered for ad libitum intake with (NRM) or without (CON) the inclusion of the ruminal probiotic. Cattle were fed a growing diet for 49 d followed by a ground corn-based diet for 124 ± 27 d until reaching the targeted final BW (635 kg for steers and 590 kg for heifers). Methane emissions were estimated using the GreenFeed system (n = 12 per treatment) prior to trial commencement (baseline; period 1), and on three (2, 3, and 4), and two (5 and 6) different sampling periods throughout the growing and finishing stage, respectively. All data were analyzed using the PROC MIXED procedure of SAS. For CH4 production (g/d), there was a tendency for an NRM supplementation × period interaction (P = 0.07) where cattle-fed diets with NRM had lower production of methane in periods 3 and 4. Including NRM in the diet decreased CH4 yield (g/kg of dry matter intake (DMI)) by 20%. For CH4 emission intensity (g/kg of average daily gain (ADG)), an interaction (P0.01) of NRM supplementation × period occurred. In periods 2 and 3, cattle-fed diets with NRM inclusion had lower CH4 emission intensity than CON cattle. During the 84-d period when all cattle were still on the finishing diet, feeding NRM increased (P = 0.02) ADG and tended to increase (P = 0.10) DMI. At the end of the 84-d period, cattle-fed NRM tended to be heavier (P = 0.06) than CON cattle. Cattle supplemented with NRM required less (P = 0.04) days on feed to reach the targeted final BW. No differences (P ≤ 0.11) were detected for gain-to-feed ratio and carcass characteristics. Cattle-fed NRM had greater abundance of uncultured rumen bacteria that may improve rumen digestion when fed a high grain diet and potentially promote the reduction of enteric CH4 production. Results from this study suggest that daily administration of NRM may be a strategy to mitigate methanogenesis and improve the growth performance of beef cattle.Greenhouse gas emissions are a major concern in the beef industry. This study examined the effects of supplementation with ruminal probiotics consisting of three native ruminal microbes (NRM) for their influence on methane reduction and growth performance of beef cattle. Eighty Angus × SimAngus-crossbred cattle were grouped by sex and weight, randomly assigned to a treatment group, control or NRM supplementation, and subsequently fed commercially relevant diets for at least 134 d with or without NRM supplementation until they reached a target finishing weight. Methane emissions and growth performance metrics were recorded at regular intervals. Cattle-fed diets with NRM had a greater average daily gain during most part of the experimental period, required fewer days to reach the finishing weight, and emitted less methane than cattle in the control treatment. Supplementing NRM can be a viable method to reduce greenhouse gas emissions while improving the performance of beef cattle-fed concentrates-based diets. more...

The objectives of this experiment were to evaluate the effect of oscillating feeding time (OFT) and corn processing (CoP) on performance and carcass characteristics of feedlot cattle. One hundred sixty-five steers (initial body weight [BW] 277.2 ± 27.80 kg) were blocked by initial BW and allotted to 24 pens. Pens within each block were randomly assigned based on a 2 × 2 factorial arrangement of treatments. The two factors were CoP (whole shelled corn vs. ground corn [GC]) and feeding time (FT) (constant FT vs. 2 hours OFT). Animals were fed the same diet, only changing the CoP method depending on the treatment. Feed offered and feed refusals were collected daily. Body weight was collected at starting day of the experiment (d1) and every 28 d until the end of the experiment. At the end of the experiment, animals were harvested in a commercial slaughter facility, and carcass data were collected by a USDA grader. Animal growth performance and carcass characteristics data were analyzed with the PROC Mixed procedure (SAS) using CoP, FT, and their interaction as fixed variables; and treatments × pen within each block and block were considered random variables. There was no CoP by FT interaction differences (P > 0.10) on animal growth performance variables, nor on hot carcass weight, back fat, rib eye area, or the percentage of kidney, pelvic, and heart fat. There was a tendency for an interaction (P = 0.08) for marbling score, where the steers from the GC processing fed on the oscillating time had a lesser marbling score than the other three treatments. Oscillating feeding time improved (P = 0.05) average daily gain; but did not affect (P ≥ 0.11) dry matter intake (DMI), nor carcass characteristics compared with feeding at a similar time every day. There were no effects (P ≥ 0.11) of CoP on growth performance, nor carcass characteristics. In conclusion, a 2-hour oscillation in FT might not decrease steer feedlot performance. This may be due to the high degree of control of DMI with feed bunk management. more...

This study evaluated the feedlot performance, carcass characteristics, and fatty acid (FA) composition of Wagyu-sired and Angus-sired cattle at a similar days on feed (D) or body weight (B) endpoint. Wagyu-sired steers and heifers (WA) from two different sires, selected for either growth (G) or marbling (M), were compared with Angus-sired steers (AN, n = 13) in two independent incomplete-block design experiments at a similar days on feed (DOF; WA-GD, n = 9; WA-MD, n = 12) in experiment 1 or similar final body weight (BW; WA-GB, n = 9; WA-MB, n = 13) in experiment 2. Cattle were offered a corn silage-based growing diet for 119 d before being transitioned over 3 wk to a finishing diet. Data were analyzed as a randomized incomplete block design. In experiment 1, AN and WA-GD cattle had a greater (P0.01) off-test BW and average daily gain (ADGP0.04) than WA-MD cattle and AN had a greater dry matter intake (DMI; P0.02) than WA-GD and WA-MD cattle. The AN and WA-GD cattle had a greater carcass weight (P0.02) than WA-MD cattle. Percent kidney, pelvic, and heart fat (KPH) was greatest (P0.01) for WA-MD cattle, followed by WA-GD cattle, and lastly AN cattle. Total lipid (P0.03) and polyunsaturated FA (PUFA; P0.01) percentage were greater for WA-MD-cattle than AN and WA-GD cattle, as they tended (P = 0.11) to have the greatest 12th rib marbling score. In experiment 2, AN-cattle needed fewer (P0.01) DOF and had a greater (P ≤ 0.02) ADG, DMI, and gain:feed than WA-GB- and WA-MB-cattle. The WA-MB-cattle had a greater (P0.01) 12th and 6th rib marbling score, USDA quality grade, and 6th rib backfat thickness than AN-cattle. Compared with AN cattle, WA-GB cattle had a greater (P ≤ 0.01) percent KPH and lesser (P ≤ 0.03) rib thickness. The WA-MB-cattle had a greater (P ≤ 0.01) concentration of total lipid and PUFA than AN- and WA-GB-cattle, and lesser saturated FA (SFA; P0.01) concentration than AN-cattle in the longissimus muscle (LM). The 6th rib location of the LM had a greater (P ≤ 0.01) percentage of total lipid and SFA, but less (P0.03) MUFA compared with the 12th rib location. In conclusion, Wagyu-sired cattle selected for marbling potential had a lesser ADG, DMI, more marbling, more PUFA, and less SFA in the LM than Angus-sired cattle regardless of slaughter endpoint. Wagyu-sired cattle selected for growth potential had a similar ADG and carcass characteristics compared with Angus-sired cattle when fed for a similar number of days on feed.Wagyu-sired steers and heifers (WA) from two different sires, selected for either growth (G) or marbling (M), and Angus-sired steers (AN) were fed for a similar days on feed (D) or to a similar final body weight (B) in two independent experiments. In experiment 1, Angus-sired steers were compared with Wagyu-sired steers and heifers when fed for a similar number of days on feed (DOF; WA-GD and WA-MD) and in experiment 2, AN were compared with Wagyu-sired steers and heifers at a similar final body weight (BW; WA-GB and WA-MB). In experiment 1, AN and WA-GD cattle had a greater rate of gain and final BW compared with WA-MD cattle. AN cattle consumed more feed compared with Wagyu-sired cattle. WA-MD had the greatest amount of kidney fat and polyunsaturated fatty acid (FA) compared with AN and WA-GD cattle. In experiment 2, AN cattle had a greater rate of gain, feed intake, with fewer DOF compared with Wagyu-sired cattle. At a similar final BW, WA-MB cattle deposited more kidney fat, marbling at the 6th- and 12th-rib, and backfat at the 6th-rib compared with AN cattle. The FA profile of the longissimus muscle from WA-MB cattle had more polyunsaturated FA, with less saturated FA compared with AN cattle. The resulting feedlot performance and carcass characteristics vary depending on the selection of Wagyu sire for growth or marbling ability. more...

Winter and spring precipitation are predicted to increase in the Midwest region of the United States, causing muddy conditions. In a previous experiment, Angus cows (8 per treatment) were paired based on initial body weight (BW) and one cow from each pair was randomly allocated to either the mud or control treatment. Though cows consumed the same amount of dry matter, cows in the mud treatment weighed 37.4 kg less than cows in the control treatment by day 269 of gestation. The objective of this experiment was to evaluate developmental programming effects of steers born to cows in the mud treatment (MUD; n = 7) or the control treatment (CON; n = 6). Steers were weighed at birth and then weekly from approximately 56 d of age until weaning and were subjected to a glucose tolerance test (GTT) and adrenocorticotropic hormone (ACTH) challenge after weaning. Steers were then placed in the feedlot for an 84-d growing phase and were weighed weekly and 12th rib back fat (BF) and ribeye area (REA) were imaged every 28 d using ultrasonography. Data were analyzed as a randomized complete block design with repeated measurements when appropriate (SAS 9.4). Although there was a 37.4 kg decrease in BW of cows by the end of gestation, there was no evidence of a pen treatment effect on calf birth weight (P = 0.60) or weaning weight (P = 0.99). Additionally, there was no evidence of a pen treatment × day effect for steer BW from birth to weaning (P = 0.67) or growing phase BW (P = 0.60). There was evidence of a treatment × day of growing phase effect (P = 0.02) for BF, such that CON steers had greater BF on day 28 of the growing phase; however, there was no evidence of a treatment × day effect for REA (P = 0.20). Furthermore, there was no evidence of a pen treatment effect for the growing phase average daily gain (P = 0.74), dry matter intake (P = 0.65), gain:feed (P = 0.48), plasma glucose concentration (P = 0.67) or plasma insulin concentration (P = 0.61) in response to the GTT, or plasma cortisol concentration in response to the ACTH challenge (P = 0.51). These results indicate that while mud increased net energy requirements for cows in the MUD treatment, there were no subsequent effects observed for steer BW, gain:feed, or response to glucose and ACTH during the growing phase.Predictions for the Midwest U.S. indicate that both winter and spring temperatures and precipitation will increase. These climatic changes could result in muddier conditions during winter and spring in the Midwest. It has previously been demonstrated that a muddy environment increases the net energy requirements of mature cow’s by approximately 3.9 Mcal/d. If cows are not provided this extra energy and are exposed to mud during late gestation, it is likely that this will cause an adverse environment for the conceptus that could result in compromised growth and metabolism later in life. This study evaluated the developmental programming effects after birth and into the growing phase with beef steers born to cows that were housed in a muddy environment during late gestation compared with steers born to cows that were housed in pens bedded with wood chips during late gestation. Based on the present results, the mature cows housed in the muddy conditions weighed approximately 37.4 kg less than cows housed in pens bedded with wood chips during late gestation, however, calf birth weight, postnatal growth, postnatal feed intake and gain:feed, and postnatal response to glucose and adrenocorticotropic hormone was not affected. This indicates that the mature cows were able to mobilize body stores and supplied the fetus with adequate nutrients during gestation without impairment of growth or postnatal response to glucose and adrenocorticotropic hormone. more...

Average temperatures in the Midwest, USA are predicted to increase 2–9°C by the end of the century; resulting in muddy pastures for spring calving beef heifers as they enter late gestation. The objective of this study was to evaluate the effects of muddy conditions on heifer body weight (BW), body condition score (BCS), conceptus free live weight (CFLW), and fetal growth when heifers were energy restricted during late gestation. Eighteen Angus heifers (n = 9/treatment) were paired based on initial BW. One heifer from each BW pair was randomly allocated to either the mud (MUD) or control (CON) treatment on day 196 of gestation. Pens in the CON treatment were bedded with wood chips, while pens in the MUD treatment were filled with mud (average depth of 19.5 ± 7.9 cm). Heifers were housed individually and fed the same diet that consisted of a limit-fed total mixed ration from day 196 to 266 of gestation that was formulated to meet 66% of the net energy for maintenance, growth, and gestation requirements. Requirements and the amount of the diet offered were adjusted weekly, and heifers were weighed and sampled for blood metabolites weekly. Data were analyzed as a randomized complete block design with repeated measurements. There was a treatment × day of gestation interaction, such that heifers had similar BW, BCS, and CFLW on day 196 of gestation. By day 266 of gestation; however, heifers in the MUD treatment weighed 43.5 kg less (P more...

Sixty Angus × SimAngus-crossbred steers (body weight [BW] 279 ± 16 kg) were used to evaluate the effect of calcium salts of palm oil inclusion (CPO) and the amount of feed offered (AFO) on plasma glucose-dependent insulinotropic polypeptide (GIP) concentration and its association with energy metabolism and marbling score (MS) in feedlot steers. Steers were blocked by BW and gain to feed (G:F) and randomly assigned to individual feedlot pens. Treatments (2 × 2 factorial) consisted of ad libitum-fed steers without (ANF) or with (AWF) the inclusion of CPO or restricted-fed steers (85% of the ad libitum intake of ANF) without (RNF) or with the inclusion of CPO (RWF). After weaning, steers were adapted to individual pens and fed a corn silage-based diet for 30 d and subsequently placed in a ground corn (GC)-based diet. Diets were given ad libitum or at 85% of the ANF intake and with or without CPO. After 59 d on the finishing diet, all steers had ad libitum access to the finishing diet until harvest. Measurements of CO2 emission and O2 consumption to estimate respiratory quotient (RQ) were taken (n = 9/treatment). Correlations between plasma GIP and insulin concentrations and RQ were analyzed. A linear regression was performed to evaluate the association of plasma GIP and MS. All data were analyzed using the PROC MIXED procedure of SAS. During the first 103 d of the trial, there were AFO × CPO interactions (P ≤ 0.01) for BW, dry matter intake (DMI), average daily gain (ADG), and net energy for maintenance (NEm) intake. Ad libitum-fed steers without CPO presented the greatest DMI among dietary treatments and had greater BW and ADG compared with steers in the RWF and RNF treatments. After all steers had ad libitum access to dietary treatments, steers that were previously restricted showed a 30% and 19% increase (P ≤ 0.01) in ADG and G:F, respectively. There was a three-way interaction time × CPO × AFO (P = 0.04) for plasma GIP concentration. There was no correlation (P = 0.96) of GIP with RQ, whereas insulin demonstrated marginal significance for a positive (P = 0.07) and negative (P = 0.08) correlation with plasma GIP and RQ, respectively. There was no association (P = 0.30) between GIP and MS. These data indicate that GIP secretion results from an interaction between CPO and energy intake depending on the time relative to feed intake that GIP might indirectly regulate energy metabolism through insulin secretion, and that GIP does not appear to be associated with MS.In ruminants, the role of glucose-dependent insulinotropic polypeptide (GIP) in energy metabolism has not been widely studied. This experiment is aimed to evaluate the effect of lipids, as calcium salts of palm oil (CPO), and amount of feed offered on plasma GIP concentration and its association with the energy metabolism, measured as respiratory quotient (RQ), and marbling score (MS) in feedlot steers. Steers were fed a corn silage-based diet for 30 d and subsequently placed in a ground corn-based diet until harvest. Diets were offered at different amounts (ad libitum or restricted) with or without the inclusion of CPO. Growth performance, blood samples, and gas exchange were measured over time. Overall, steers fed diets with CPO gained more body weight when they were restrict-fed but not when they were ad libitum fed. There was no association between GIP and RQ. Insulin tended to be positively and negatively correlated with plasma GIP and RQ, respectively. There was no association between GIP and MS. Our results suggest that GIP secretion results from an interaction between dietary CPO and energy intake depending on the time relative to feeding and that GIP is not associated with MS. more...

The objective of the present experiment was to evaluate the effect of maternal supplementation with fatty acids (FAs) and methionine (Met) during late gestation on offspring growth, energy metabolism, plasma resolvin (RvD1) concentration, carcass characteristics, and hepatic mRNA expression. Ewes (5 pens/treatment; 3 ewes/pen) blocked by body weight (BW) were assigned to one of four treatments from day 100 of gestation until lambing. The treatments were: basal diet (NS) without FAs or Met supplementation; FA supplementation (FS; 1.01 % of Ca salts, containing n-3 FA); Met supplementation (MS; 0.1 % of rumen-protected methionine); and FS and MS (FS-MS). At birth (day 0), ewes and lambs were placed in a common pen. On day 60, lambs were weaned, sorted by sex, blocked by BW, and placed on a common finishing diet for 54 d (FP). A lamb per pen was used for a glucose tolerance test (GTT) after the FP. Carcass characteristics were recorded on day 56. Lamb data were analyzed as a randomized complete block design with a 2 × 2 × 2 factorial arrangement, with repeated measurements when needed (SAS 9.4). At weaning, lambs born to MS- or FS-fed ewes were heavier than lambs born from FS-MS ewes (FS × MS × Time; P = 0.02). A marginal significant FS × MS interaction (P = 0.09) was also observed on RvD1; lambs born to ewes in the NS and FS-MS treatments showed a lower RvD1 plasma concentration when compared with lambs born to FS- or MS-fed ewes. Lambs born to dams fed FA showed an increase (P = 0.05) in liver COX-2 mRNA relative expression. Lambs born to ewes supplemented with Met showed an increase (P = 0.03) in liver FABP4 mRNA expression. An FS × MS × Time interaction (P = 0.07) was observed in plasma glucose during the GTT; lambs born from FS-fed ewes showed lower plasma glucose concentration than lambs born to Met-supplemented ewes at 2 min after bolus administration. During the GTT, a marginal significant effect (P = 0.06) was observed for the lamb average insulin concentration due to maternal Met supplementation during late gestation, where these lambs had the lowest plasma concentration. Contrary to our hypothesis, the interaction of FA and Met supplementation during late gestation did not show a greater positive effect on offspring postnatal growth and metabolism. However, the individual supplementation of each nutrient has an effect on offspring development with a concomitant change in markers involved in the inflammatory response and energy metabolism.Late gestation supplementation of omega-3 fatty acids (FAs) or methionine (Met) alters the offspring’s development. However, the effect of both nutrients on the physiology and growth of the progeny has not been explored. The experiment’s objective was to evaluate the effect of dam supplementation with a Met and the omega-3 FAs, such as eicosapentaenoic and docosahexaenoic acids, during late gestation on growth, energy metabolism, and inflammatory response markers of the lamb. Ewes received one of the four following treatments: basal diet without FA or Met, FA supplementation, Met supplementation, or FA and Met supplementation. Supplementation of omega-3 FAs and Met did not show a greater effect on postnatal growth and metabolism of the offspring compared with the supplementation of each nutrient individually. However, individual supplementation influences offspring development with a concomitant change in markers involved in the inflammatory response and energy metabolism. Results of the present experiment suggest that offspring born to mothers that were fed FAs or Met on late gestation could have the ability to better cope with inflammatory processes, which could improve their long-term growth performance. Moreover, maternal supplementation of Met during late gestation could modulate offspring’s glucose–insulin system, which may also affect offspring’s growth. more...

To evaluate the effect of supplementing feedlot cattle with native rumen bacteria (NRB; Prevotella albensis, Succinivibrio dextrinosolvens, and Chordicoccus furentiruminis) in growth performance, carcass characteristics and gas emissions, Angus × SimAngus-crossbred (body weight (BW) 353 ± 64 kg) steers (n = 32) and heifers (n = 48) were used in randomized complete block design. Cattle stratified by BW were randomly assigned to 4 pens (2/treatment) and fed a corn silage-based diet for 49 d (backgrounding) followed by a ground corn-based diet for 84 d (finishing). When reaching desired finished BW, cattle were harvested. Diets were offered ad libitum and with (WNB) or without (CON) the inclusion of NRB feed supplement. Measurements of CH4 emissions were taken using the GreenFeed system (n = 12/ treatment). All data were analyzed as a mixed procedure (Table 1). There was a treatment (P ≤ 0.05) effect for CH4 emissions yield [g/kg dry matter intake (DMI)] and intensity [g/kg average daily gain (ADG)] during the growing period. Including NRB in the diet during growing, decreased CH4 emissions yield and intensity by 13.5% and 29%, respectively. During the first 84-d period on the finishing diet (d133), feeding NRB increased (P = 0.02) the ADG and tended to increase (P = 0.10) DMI. At d133, cattle fed NRB tended (P = 0.06) to be heavier than cattle in the CON treatment. Days on feed (DOF) was 9 days longer for CON animals than those of WNB animals (P = 0.04). No other differences (P ≥ 0.25) were detected throughout the experimental period and no differences (P ≥ 0.11) were observed in carcass characteristics. Results from this study indicate that feeding NRB decreased methane yield and intensity in the backgrounding period, improved finishing performance of beef cattle, and decreased DOF more...

The development of a rumen-protected fatty acid (RPFA) product can make the product undigestible in the small intestine. The objective of this experiment was to measure the digestibility of two prototype feeds RPFA enriched with omega-3. Twenty-four Leghorn cockerels (85-week-old, 2.5 kg body weight) were individually caged and assigned randomly to 4 treatments, with 6 cockerels per treatment. Cockerels were fasted for 24 h and after this period the cockerels were tube fed 40 g of 4 different treatment diets: T1) 80% corn and 20% crystalline cellulose, T2) 80% corn and 20% unprotected RPFA, T3) 80% corn and 20% RPFA treated for 3 hours, and T4) 80% corn and 20% RPFA treated for 6 hours. The RUPFA ingredients were 55% modified soy lecithin, 40% fish oil, 5% dextrose. The protection treatment of RPFA is described in the pending patent (US 2020/0197346 A1). After 48 h all the excreta from the cockerels was collected and dried in an oven at 60 °C for 72 h. Dried excreta samples and diets were analyzed for total lipids. Data were analyzed as complete randomized block design using linear mixed model. Lipid digestibility was different for treatments (P < 0.01). Lipid digestibility was lesser (P < 0.01) for T1 compared with T2, T3, and T4 (87.6% vs 96.8%, 95.5%, and 96.4% (± 0.34) for T1, T2, T3, and T4 respectively). There were no differences (P > 0.1) between T2, T3, and T4. We conclude from these data that the processing of the RPFA product does not change the digestibility of the lipids in non-ruminants. more...

Our objective was to determine the effect of different levels of dry matter intake (DMI) on O2 consumption, CO2 emission, growth, and carcass characteristic in feedlot cattle. The experiment used 60 individually fed backgrounded Angus × SimAngus-crossbred steers (n = 30) in a randomized complete block design. Steers (paired blocked by body weight and gain to feed ratio (G:F) were randomly allocated to one of the following treatments: ad-libitum (AI) or restricted intake (RI; the same diet fed at 85% of the AI) finishing diet. The diet contained 61% cracked corn, 9% corn silage, 15% DDGS, 5% soyhulls, and 10% of a protein-mineral-vitamin premix. Measurement of CO2 emission, and consumption of O2, were taken using the Greenfeed system (n = 15/treatment) once the steers were fed for 140 days. Plasma and gas samples were collected 10 d before slaughter, 1 h before and 2 h after feeding. Plasma glucose and insulin concentration and gasses (O2 and CO2) were analyzed using the MIXED procedure of SAS evaluating the fixed effect of treatment, time (repeated measurement) and their interaction. Growth and carcass characteristics were analyzed with a similar model, without the time statement and its interaction. Compared with RI, AI steers had greater (P < 0.01) DMI and average daily gain (ADG). Steers on AI tended to have greater final body-weight (BW) (P = 0.07) and ribeye area (P = 0.09) (Table 1). There was no effect of treatment (P ≥ 0.11) on G:F, subcutaneous (BF) and intramuscular (IM) fat, O2 consumption and CO2 emission. Plasma glucose concentration of AI steers were greater before and after feeding than RI (P < 0.05; Table 2). In conclusion, feeding steers ad-libitum increased DMI, ADG, and plasma glucose concentration, but does not affect G:F, BF, IM fat, CO2 emission, and consumption of O2. more...

The objective of this experiment was to evaluate the of use different doses of a rumen protected fatty acid supplement in feedlot heifers. Seventy-two (cross bread) heifers were blocked by body weight and animals within each block were randomly allotted to a pen. Each pen had 4 heifers, and there were 6 pens per treatment. All animals were fed a basal diet of 14% corn silage, 73% dry rolled corn, 10% cracked soybeans, 1% urea, and 2% mineral vitamin mix for 83 days. Each treatment received different dose of a rumen-protected fatty acid supplement (RPFA), which contained 40% flaxseed oil, 55% treated soy lecithin, and 5% dextrose; processed using the procedure described in the patent (pending: US 2020/0197346 A1). Treatments were T1: 125 g RPFA; T2: 250 g of RPFA, and T3: 375 g of RPFA. Treatments were daily top dressed. Heifers were weighted on days 0, 50, and 83. Longissimus dorsi muscle (LMA) and back fat (BF) at the 13 rib were measured using ultrasound day 0 and 83, before the animals were sent to slaughter. Dry matter offered per day and refusal collected twice a week were used to estimate dry matter intake (DMI). Data were analyzed as a randomized complete block design, with treatment as a fixed variable and block as a random variable. Means were separated using a polynomial contrast. There were no differences (P ≥ 0.16; Table 1) on final body weight, average daily gain (ADG), DMI, gain to DMI ratio, or dressing percentage. There where quadratic tendencies (P ≤ 0.1; Table 1) for hot carcass weight (HCW), LMA, and BF. Based in the results from the current experiment, feeding 100 g of flaxseed oil (250 g of RPFA) improves HCW and LMA but also BF, without affecting growth and DMI. more...

One-hundred twenty crossbreed steers (initial body weight (BW) 566 ± 42 kg) were used to evaluate the interaction of protein source (PS) and nonroughage NDF content (NRFC) in finishing diets of feedlot cattle fed free-choice hay on performance and carcass characteristics. Steers were stratified by BW and randomly assigned to 8 pens (2 × 2 factorial) and fed for 104 ± 10 d. Four dietary treatments were investigated: (1) distillers’ dry grains with solubles (DDGS) and a low NRFC (DLF), (2) DDGS and a high NRFC (DHF), (3) soybean meal (SBM) and a low NRFC (SLF), (4) SBM and a high NRFC (SHF). Free-choice grass hay and concentrates were offered in a different bunk. Data were analyzed as a randomized complete block design. Do to the confounded effect of PS and protein intake, a linear regression was used to evaluate the effect of protein intake in growth performance. For gain to feed ratio (G:F) an interaction tended to occur (P = 0.10) between PS and NRFC. Steers on the DHF treatment had a lower G:F compared with SLF and SHF. Feeding SBM increased (P = 0.05) final BW, tended to increase (P = 0.06) average daily gain (ADG), and decreased (P = 0.05) hay intake (HI) compared with steers fed DDGS. There was a positive association (P ˂ 0.01) of crude protein intake with ADG and FBW. Dietary NRFC did not change (P ≥ 0.3) final BW, ADG, DMI, and HI. Protein source did not affect (P ≥ 0.16) hot carcass weight (HCW), longissimus muscle (LM) area, dressing, 12th rib fat thickness, or marbling score (MS). No differences were detected between NRFC for dressing, HCW, LM area, or MS (P ≥ 0.18); but diets with greater NRFC decreased (P = 0.03) the 12th rib fat thickness. Steers in the SHF treatment presented the lesser kidney-pelvic-heart fat compared with the remaining treatments (PS × NRFC interaction, P = 0.04). Soybean meal inclusion/increase in protein intake improved growth performance of feedlot steers compared with DDGS, despite protein intake meet the protein requirement. Increasing the NRFC did not affect growth or HI but decreased feed efficiency of steers fed DDGS. more...

The U.S. Department of Agriculture (USDA) yield grade (YG) equation is used to predict the retail yield of beef carcasses, which facilitates a more accurate payment for cattle when they are sold on a grid pricing system that considers carcass composition instead of body weight alone. The current USDA YG equation was developed over 50 yr ago. Arguably, the population of cattle used to develop the YG equation is different than the current diverse U.S. beef cattle supply today. The objectives of this manuscript are to promote the adoption and use of precision agriculture technologies (i.e., camera grading and electronic animal identification) throughout the U.S. beef supply chain as a means to enhance the ability of the USDA YG equation to more accurately predict the retail yield across the population of cattle that contributes to the current U.S. beef supply. Camera grading has improved the accuracy of determining beef carcass retail yield; however, the use of electronic animal identification would allow for additional information to be passed back and forth between the packer, cattle feeder, and producer. Information, such as sex, genetics, medical treatment history, diets consumed, and growth promotant administration, as well as other information could be used to create additional variables for a new augmented USDA YG equation. Herein, fabrication yields demonstrated a 5.6 USDA YG and 12.8% boneless closely trimmed retail cut difference between actual cutout measurements and calculated values from the USDA YG equation for Jersey-influenced cattle. Evidence of such disparities between calculated and actual values warrants a reevaluation of the USDA YG system and consideration for implementing advancements in precision agriculture to improve the prediction of beef carcass retail yield to more accurately account for the large amount of variation in beef carcass retail yield from the cattle in the United States. more...

The objectives of this study were to evaluate the effect of the use of yeast fermentation products (YFP) on growth, hormone concentration, and gut permeability in dairy calves. One hundred and twenty heifers were randomly assigned to one of three treatments: control group with no YFP supplementation (C), Saccharomyces cerevisiae fermentation products (SCFP) supplementation (1 g/head/d of SmartCare [Diamond V] in the milk and 0.7% on dry matter basis of NutriTek [Diamond V] on the starter feed), or Aspergillus oryzae fermentation extracts (AOFE) supplementation (3 g/head/d of LXtract1224 [Biozyme Inc.] in the milk). All calves received 6 L/d of pasteurized milk and had ad libitum access to water and dry feed along the study. Body weight (BW) was recorded at birth and on days 14, 30, and 45 and at weaning. Dry feed (starter) offered was measured daily and refusals twice a week to obtain starter intake (SI). Diarrhea events were recorded daily and fecal scores were classified by using a four-point scale. Blood was sampled on days 7 and 14 for plasma glucose, nonesterified fatty acids (NEFA), insulin, and IL-1β concentrations. Lactulose and D-mannitol were included in the morning feeding of day 14 and blood samples were taken an hour after feeding for assessment of intestinal permeability. On day 14, blood samples were taken for plasma glucagon-like peptide 2 (GLP-2) concentration. On day 30, fecal samples were collected for measurements of Salmonella and Escherichia coli concentration on feces. No treatment differences (P ≥ 0.13) were found for BW or SI. There was a time by treatment difference (P = 0.01) in average daily gain (ADG) on day 45 where C animals had a greater ADG when compared with SCFP and AOFE. Diarrhea incidence did not change between treatments (P = 0.97) and Salmonella and E. coli were not found in feces. There were no differences (P > 0.60) between treatments for plasma GLP-2, glucose, insulin, lactulose, nor D-mannitol concentrations. There was a time by treatment tendency (P = 0.06) for NEFA concentration which tended to be greater on day 7 for C and AOFE when compared with day 14. Plasma IL-1β concentration showed a treatment tendency which tended (P = 0.06) to be greater for SCFP when compared with C. Under the current conditions, supplementation with YFP did not improve performance parameters. Plasma GLP-2 concentration, intestinal permeability, and plasma metabolites did not differ after yeast fermentation products supplementation. more...

Objective This experiment investigated the effects of sire breed and sex on the feedlot performance, carcass yield, fatty acid composition, and tenderness of crossbred Jersey cattle. Materials and Methods Crossbred Jersey steers and heifers sired by Angus (n = 9, 11), SimAngus (n = 10, 19), and Red Wagyu (n = 15, 7) bulls were used in a randomized complete block design. Results and Discussion Adjusted to a similar initial BW, Angus- and SimAngus-sired cattle had a greater ADG (P ≤ 0.01) and average daily DMI (P ≤ 0.01), resulting in a greater off-test BW (P ≤ 0.04) and fewer days on feed (P ≤ 0.01) compared with Wagyu-sired cattle. At a similar adjusted hot carcass weight, carcasses from Angus-sired cattle had a greater fat thickness (P ≤ 0.01) and less kidney fat (P ≤ 0.01) compared with carcasses from SimAngus- and Wagyu-sired cattle. Sire breed did not affect total red meat yield (P = 0.32), fat yield (P = 0.28), and bone yield (P = 0.35). Warner-Bratzler shear force values were greater (P ≤ 0.01) for steaks from Angus-sired cattle compared with steaks from SimAngus- and Wagyu-sired cattle. Steaks from Angus-sired cattle had a greater marbling score (P ≤ 0.01) and percentage of total lipid (P ≤ 0.01) compared with steaks from SimAngus- and Wagyu-sired cattle. Implications and Applications Appropriate selection of a terminal sire breed will depend on where the producer intends to sell in the production chain, because different sire breeds excel in different growth and carcass traits. more...

The objectives were to evaluate the associations of lying time (LT) during the first 14 d in milk (DIM) with milk yield, cyclicity (CYC), culling within 60 DIM (CULL), and reproductive performance of lactating dairy cows. A total of 1,052 Holstein cattle (401 nulliparous heifers and 651 parous cows) from 3 commercial dairy farms had electronic data loggers (IceQube, IceRobotics, Edinburgh, UK) placed on a hind leg 14 ± 3 d before the expected parturition date and removed at 14 ± 3 DIM to assess their LT. Serum concentrations of β-hydroxybutyrate were determined at 7 ± 3 and 14 ± 3 DIM. Cases of retained placenta, metritis, mastitis, pneumonia, and digestive disorders within 30 DIM were recorded and lactating cows were categorized into 1 of 4 groups: (1) nondiseased (ND, n = 613; cows without ketosis or any other diagnosed health condition); (2) cows with only ketosis (KET, n = 152); (3) sick cows experiencing ≥1 health conditions but without ketosis (SICK, n = 198); or (4) cows with ketosis plus ≥1 health condition (KET+, n = 61). Ultrasound was performed at 28 ± 3 and 42 ± 3 DIM to assess ovarian cyclicity (presence or absence of corpus luteum). Milk yield at first Dairy Herd Improvement Association test was not associated with LT during the first 14 DIM, but it was negatively correlated with the coefficient of variation of LT during the first 14 DIM. Lactating dairy cows experiencing KET+ had the lowest milk yield compared with ND, regardless of parity. Parity, health status, and season were significantly associated with CYC and CULL. Lying time had a significantly linear association with the risk of being culled: for every 1-h increment of LT during 0 to 14 DIM, the risk of culling within 60 DIM increased by 1 percentage point. Lying time had a negative quadratic association with cyclicity at 42 DIM. Multiparous cows with a LT of 9 to 13 h/d had a significantly greater probability of pregnancy up to 300 DIM compared with cows with a LT >13 h/d. Regardless of parity, KET+ cows had significantly higher proportion of culling within 60 DIM and decreased probability of pregnancy up to 300 DIM compared with ND cows. These findings suggest that there is an optimum daily LT range for early postpartum cows housed in freestall barns, different from that reported for mid-lactation cows, with the potential for improved survival, health, and the overall performance (milk yield and reproduction). more...

The purpose of this study was to evaluate the effect of intranasal oxytocin administered at abrupt weaning on weaning behaviors such as walking distance and time devoted to walking, calf body weight, and plasma non-esterified fatty acids (NEFAs), β-hydroxybutyrate (β-HB), and cortisol. Twenty Simmental × Angus heifer calves were randomly assigned to one of two treatments: intranasal oxytocin (OXT; n = 10) or intranasal saline (CON; n = 10). All calves were given the respective intranasal treatment on the day of weaning (day 0) and then placed on pasture together. Calves were weighed and a blood sample was obtained on days 0, 1, 7, and 14 postweaning. Blood samples were subsequently used to quantify plasma NEFA, β-HB, and cortisol concentrations. All calves in both treatment groups were fitted with an individual global positioning system that recorded calf location every 10 s for a 16-h period on days 0, 7, and 14 to quantify and evaluate walking behaviors. There was no treatment × day effect for distance walked (P = 0.82), walking time (P = 0.80), non-walking time (P = 0.88), area utilization index (P = 0.84), calf body weight (P = 0.82), average daily gain (P = 0.54), NEFA (P = 0.22), or cortisol concentrations (P = 0.32). There was a tendency for a treatment × day effect observed for average walking speed (P = 0.09) and β-HB (P = 0.10), such that calves in the CON treatment tended to have lesser average walking speeds on day 14 and tended to have greater β-HB concentration after weaning. There was a treatment effect (P = 0.02) for NEFA concentrations, with the CON calves having a greater plasma NEFA concentration throughout the study compared with OXT calves. These data imply that OXT calves may have had differing metabolic responses immediately after weaning that could have altered the mobilization of NEFA, but this change was not substantial enough to impact body weights or walking behaviors. more...

In mammals, including sheep and mice, lactation attenuates the hypothalamo-pituitary-adrenal axis and plasma cortisol concentration. Oxytocin, one neuropeptide present in the blood during lactation, may contribute to such stress attenuation. Providing oxytocin intra-nasally increases plasma oxytocin concentration in cattle and can be used in non-lactating cows to mirror plasma oxytocin concentration of lactating cows. Therefore, our hypothesis was that there would be no difference in plasma cortisol between non-lactating beef cows intra-nasally administered oxytocin and lactating beef cows intra-nasally treated with saline. Twenty Bos taurus cows were randomly allocated by lactational status to one of four treatments, in a 2×2 factorial arrangement: 1) Non-lactating, saline (NL-S; n = 5); 2) Non-lactating, oxytocin (NL-OXT; n = 5); 3) Lactating, saline (L-S; n = 5); and 4) Lactating, oxytocin (L-OXT; n = 5). Two hours pre-treatment, cows were catheterized, moved to their appropriate chute and baseline blood samples were collected at -60, -45, -30, and 0 minutes before treatments were administered. Directly following the 0-minute sample, cows were administered their intra-nasal treatment via a mucosal atomization device. Subsequently, blood was collected at 2, 4, 6, 8, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, and 120 minutes. Non-lactating cows had greater (P = 0.02) plasma cortisol concentration compared with lactating cows. There was no lactation by treatment interactions for either plasma cortisol (P = 0.55) or oxytocin (P = 0.89) concentration. Although a treatment by time interaction was identified for oxytocin (P < 0.0001), there was no main effect of lactation on plasma oxytocin concentration (P = 0.34). Similar oxytocin and dissimilar cortisol concentration in lactating and non-lactating cows indicate that oxytocin alone cannot be responsible for reduced plasma cortisol in lactating ruminants. Further investigations are needed to elucidate alternative mechanisms that may be involved in the stress hypo-responsive condition of lactating mammals. more...

The objective of this experiment was to evaluate the effects of feeding different levels concentrations of dietary calcium propionate (CaPr) on lambs’ growth performance, ruminal fermentation parameters, glucose–insulin concentration, and hypothalamic mRNA expression for neuropeptide Y (NPY), agouti-related peptide (AgRP), and proopiomelanocortin (POMC). Thirty-two individually fed lambs were randomly assigned to four treatments: (1) control diet (0 g/kg of CaPr), (2) low CaPr, (30 g/kg dry matter (DM)), (3) medium CaPr, (35 g/kg DM), and (4) high CaPr (40 g/kg DM). After 42 days of feeding, lambs were slaughtered for collecting samples of the hypothalamus. Data were analyzed as a complete randomized design, and means were separated using linear and quadratic polynomial contrast. Growth performance was not affected (p ≥ 0.11) by dietary CaPr inclusion. The ruminal concentration of total volatile fatty acids (VFA) increased linearly (p = 0.04) as dietary CaPr increased. Likewise, a linear increase in plasma insulin concentration (p = 0.03) as dietary CaPr concentration increased. The relative mRNA expression of NPY exhibited a quadratic effect (p &lt, 0.01), but there were significant differences in the mRNA expression of AgRP and POMC (p ≥ 0.10). Dietary calcium propionate did not improve lamb growth performance in lambs feed with only forage diets. Intake was not correlated with feed intake with mRNA expression of neuropeptides. more...

Future climate projections for the Midwest U.S.A. predict increased winter rainfall. The increase in winter rainfall will consequently increase soil moisture and allow for muddy conditions in paddocks. Muddy conditions can directly affect cows during late gestation by compromising insulative properties of the hair coat. It is likely that cold climatic conditions and mud increase a cow’s maintenance requirement during gestation and may affect growth of the fetus. The objective of this study was to evaluate effects of muddy conditions on cow body weight (BW) and fetal growth during late gestation. Sixteen multiparous Angus cows (n = 8/treatment) were paired based on initial BW. One cow from each pair was randomly allocated to either the mud (MUD) or control (CON) treatment. Pens in the CON group were bedded with wood chips, while pens in the MUD group were designed to create a muddy lot (average depth of 23.6 ± 5.8 cm). Cows were housed individually and fed the same diet. Each pair was fed based on the NRC recommendations for maintenance and gestation. From day 213 to 269 of gestation, cows were weighed weekly. Conceptus free live weight (CFLW) was then calculated by subtracting the estimated weight of the gravid uterus from the cow’s weekly BW. Data were analyzed as a randomized complete block design with repeated measurements (SAS 9.4). At time of study initiation, cows were of a similar BW (P > 0.05). By day 269 of gestation, the CFLW of the cows in the MUD group weighed 37.4 kg less compared with the CON group (P < 0.01), though calf birth weight was not different (P = 0.72). Cows in the CON group maintained CFLW throughout the treatment period, however, cows in the MUD group did not maintain CFLW during the treatment period. more...

To evaluate the effect of soy-hulls (SH) inclusion in a ground corn-based diet with either distillers dry grains with solubles (DDGS) or soybean meal (SBM) as the protein source (PS), on growth and carcass characteristics of feedlot cattle offered free-access hay; one-hundred and nineteen crossbreed steers (initial BW 566 ± 42kg) were blocked by weight, randomly assigned to 8 pens, and fed for 104 ± 10d. Four dietary treatments were evaluated: 1) DDGS without SH inclusion, 2) DDGS and high inclusion of SH, 3) SBM and low inclusion of SH, and 4) SBM and high inclusion of SH. Diets were formulated to be isonitrogenous. Grass-hay was offered ad-libitum and separate from the concentrates in a different bunk (GrowSafe system). Data was analyzed as a 2×2 factorial considering the fixed effects of treatments and their interaction, and the random effects of block and steer within block. For gain to feed and kidney-pelvic-heart fat (KPH), an interaction occurred (P ≤ 0.10) between PS and SH inclusion (Table 1 and 2, respectively). With greater inclusion of SH, feed efficiencies of steers fed SBM improved compared with feed efficiencies of steers fed DDGS. Steers fed SBM and high SH had the lower KPH content. Feeding SBM increased (P = 0.05) final body weight, tended to increase (P = 0.06) the average daily gain, and decreased (P = 0.05) hay intake compared with steers fed DDGS (Table 1). No differences were observed (P ≥ 0.14) in carcass characteristics between PS and SH inclusion, except for backfat thickness which increased (P = 0.03) with lower SH inclusions (Table 2). These data suggest that opting for SBM as an alternative of DDGS as the protein source of ground corn-based diets, could conceivably enhance the finishing performance of feedlot steers regardless of the SH inclusion levels, and improve feed efficiency with greater levels of dietary SH. more...

Glucose tolerance tests (GTT) are commonly performed in beef cattle to evaluate the glucose-insulin signaling pathway. Blood samples are obtained via a catheter and then transferred back to the laboratory for further analysis. A hand-held glucometer used chute-side can make performing GTT’s and quantifying blood glucose concentration much easier and faster for research purposes. The purpose of this study was to evaluate the agreement between a hand-held electronic glucometer (Precision Xtra; Abbott Diabetes Care Inc., Mississauga, ON, Canada) for chute-side use in beef cattle compared with a colorimetric assay in the laboratory (Stanbio Glucose LiquiColor; Stanbio Laboratory, Boerne, TX, USA). A GTT was performed on 13 Simmental × Angus steers during the growing phase. Blood samples were obtained via a jugular catheter. Glucometer readings were taken immediately after blood was sampled from the jugular with no preservative, and laboratory measurements were conducted on plasma preserved with sodium fluoride. A paired t-test (P = 0.40), Pearson’s correlation (P < 0.001; r = 0.95), Bland-Altman plot, and Lin’s concordance correlation coefficient (LCCC = 0.90) were completed to evaluate the performance of the glucometer relative to the results from the laboratory assay. Based on the results, we conclude that the glucometer is an acceptable method for measuring blood glucose concentration in beef cattle under field conditions. more...

Lambs born from dams supplemented with different sources of fatty acids (FA) during late gestation have a different growth rate and plasma glucose concentration. The main objectives of this experiment were to evaluate the effect of supplementing different sources of FA during late gestation on offspring plasma metabolite concentrations, growth, and on a glucose tolerance test (GTT) during the finishing phase. Fifty-four lambs (18 pens, 3 lambs/pen) were born from ewes supplemented during late gestation with one of three treatments: (1) no FA (NF), (2) a source of monounsaturated FA (PDS, 1.01% of Ca salts), or (3) a source of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (EDS, 1.01% of Ca salts containing). At birth (day 0), supplementation ceased, and all ewes and lambs were placed in a common pen. On day 60, lambs were weaned, grouped by sex, blocked by body weight (BW), and placed on a common finishing diet for 54 days (FP). One lamb per pen was used for the GTT after the FP. There was a tendency for FA × Sex × Day interaction (p = 0.08) on lamb growth during the finishing period, with PDS females being heavier than PDS males, while EDS males were heavier than EDS females at day 60. There was a tendency for FA × Sex interaction (p = 0.06) for plasma insulin concentration for the GTT. Plasma insulin concentration of wethers increased as FA unsaturation degree increased during the GTT, the opposite happened with the plasma insulin concentration of female lambs. In conclusion, FA supplementation during late gestation tended to modified growth and insulin response to a GTT, these changes differed with the degree of FA unsaturation of the supplement and lamb sex. more...

Simple Summary The objective of the current review is to provide a broad perspective on developmental program aspects of dietary n-3 FA supplementation in ruminants during pre-conception, conception, pregnancy, early life, including its effects on production, lipid metabolism, and health of the offspring. Offspring growth and metabolism could change depending on the FA profile and the stage of gestation when the dam is supplemented. Despite this extended review we are highlighting areas that we consider that there is a lack of information. Abstract Nutrition plays a critical role in developmental programs. These effects can be during gametogenesis, gestation, or early life. Omega-3 polyunsaturated fatty acids (PUFA) are essential for normal physiological functioning and for the health of humans and all domestic species. Recent studies have demonstrated the importance of n-3 PUFA in ruminant diets during gestation and its effects on pre-and postnatal offspring growth and health indices. In addition, different types of fatty acids have different metabolic functions, which affects the developmental program differently depending on when they are supplemented. This review provides a broad perspective of the effect of fatty acid supplementation on the developmental program in ruminants, highlighting the areas of a developmental program that are better known and the areas that more research may be needed. more...

Supplementation with omega-3 and omega-9 fatty acids (FA) during late gestation regulates offspring development; however, their effect in the first third of gestation is unknown in sheep. The objective of this experiment was to evaluate the effects of the maternal supplementation with an enriched source of monounsaturated FA (MUFA) or an enriched source of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) during the first third of gestation on productive performance on ewes and offspring, and hypothalamic neuropeptides on offspring. Seventy-nine post-weaning lambs, born of sheep supplemented in the first third of gestation with 1.61% Ca salts rich with MUFA or EPA+DHA (dam supplementation, DS), were distributed in a 2×2 factorial arrangement of treatments to finishing diets containing 1.48% of Ca salts of MUFA or EPA+DHA (lamb supplementation, LS). The finishing period of the offspring lasted for 56 d. During the finishing period dry matter intake (DMI, daily) and body weight (BW) were recorded. Plasma was collected for metabolites analysis. Twenty-four lambs were slaughtered, and hypothalamus was collected for mRNA expression of hormone receptors, neuropeptides, and lipid transport genes. The data were analyzed with a mixed model in SAS (9.4) using repeated measurements, when needed. There was a DS×LS interaction for BW (P = 0.10) where LS with EPA+DHA born from DS with MUFA were heavier than the other 3 treatments. Lambs born from DS with MUFA have a greater DMI (P < 0.01) than the offspring born from DS with EPA+DHA. Lambs born from MUFA supplemented dams had a greater (P ≤ 0.05) hypothalamus mRNA expression for cocaine and amphetamine regulated transcript, growth hormone receptor, metastasis suppressor 1, leptin receptor, pro-opiomelanocortin, and Neuropeptide Y. These results indicate that growth depends not on the type of FA during the finishing phase but the interaction of different sources of FA ad different stages. Also, supplementation with FA during early pregnancy changes productive performance and neuropeptides’ mRNA expression of lambs independently of the finishing diet. more...

Beef calves express behaviors such as walking and vocalizing to a greater extend during weaning. These behaviors increase production costs due to compromised calf growth, health, and welfare. Oxytocin treatment reduces anxious behaviors and attenuates the HPA axis, thus the objective of this experiment was to evaluate the effects of oxytocin on calf growth, cortisol, and distance walked at weaning. A total of 20 Angus x Simmental heifer calves were randomly allotted to each treatment group (n = 10), intranasal oxytocin or saline (OXT, CON). All calves were administered the respective intranasal treatment at weaning (day 0), and then placed in the same pasture. Calves were weighed and blood sampled on days 0, 1, 7, and 14. Blood samples were used to quantify non-esterified fatty acids (NEFA), β-hydroxybutyrate, and cortisol. Each heifer was fitted with a global positioning system collar that recorded calf location every 10 seconds for 16 h on days 0, 7, and 14. To further evaluate calf behavior, observations were made on days 0, 7, and 14 using instantaneous scan sampling from 0730 to 0830, 1200 to 1300, and 1700 to 1800 h. Data were analyzed using a completely randomized design with repeated measures model (SAS 9.4). Providing calves with intranasal oxytocin on the day of weaning did not have an effect on the distance walked, observed behavior, body weight, β-hydroxybutyrate, or cortisol concentrations, however, there was a day effect (P < 0.05) for these variables. Intranasal oxytocin treatment did affect NEFA concentrations, as calves in the CON group had greater NEFA concentrations on day 1 compared with calves in the OXT group (P < 0.05). These data imply that intranasal oxytocin could have the capacity to decrease mobilization of NEFA, but this change was not enough to affect body weight 14 days after weaning. more...

Estradiol administration increases mammary parenchyma growth and can increase the mass of the mammary fat pad (MFP) in calves. Estradiol can affect fatty acid metabolism, but it is unknown how estradiol affects the fatty acid profile of the MFP and if these effects are consistent across adipose stores. The objective of this investigation was to determine if fatty acid profiles were affected by estradiol administration and if this response is adipose tissue type specific. Holstein heifer calves were reared on a common diet and administered 12 daily injections prior to euthanasia at 82 days of age. Injections were either daily injections of corn oil (n = 4; CON), 9 injections of corn oil followed by 3 injections of estradiol (n = 4; SHORT), or 12 injections of estradiol (n = 4; LONG). Fatty acids were extracted from MFP and subcutaneous adipose tissues samples and analyzed using gas chromatography. Data were analyzed using a mixed model considering the effect of treatment, adipose tissue depot, their interaction, and the random effect of animal. Only significant treatment effects and treatment-adipose type interactions are presented here (Table 1). Estradiol administration (SHORT and LONG) increased total C18:1 fatty acids (P = 0.05), and tended to increase non-C18:2 t10 c12 CLAs, C18:3, and total omega-3 fatty acids (P ≤ 0.1) in the MFP and subcutaneous adipose tissues relative to CON. There was a treatment by tissue interaction for C18:1 trans-10 (P = 0.01), and a tendency for C18:1 trans-11 and C18:2 trans-10 cis-12 (P ≤ 0.1) indicating that estradiol’s effects on fatty acids are tissue specific. Together, these results indicate that the MFP responds differently to estradiol than subcutaneous adipose tissues and that these alterations are associated with different periods of induced mammary growth via estradiol. more...

Future climate predictions suggest greater precipitation events and an increase in mean ambient temperature during winter months, creating wet and muddy conditions during the last third of gestation for spring calving beef cows. Cows housed in these conditions will likely have increased energy requirements; however, there is limited data on cow requirements in such circumstances. The objective of this study was to evaluate the effects of muddy environmental conditions on cow body weight (BW) and body condition score (BCS) in late gestation. Twenty multiparous Angus cows (n = 10/treatment) housed and fed individually were used in this study. Cows were paired based on initial BW, and one cow from each pair was randomly allocated to either the mud (MUD) or control treatment (CON). Cows in the CON treatment were bedded with wood chips and not exposed to mud, while cows in the MUD treatment were housed in mud (23.6 ± 5.8 cm). Cows were fed the same diet, and each pair was fed to the CON cow’s requirements for maintenance and day of gestation. Maintenance requirements were adjusted weekly. From 213 to 269 days of gestation, cows were sampled for BW and BCS weekly. Data were analyzed as a randomized complete block design with repeated measurements, and the SLICE option of SAS was used for mean separation. All cows started at similar BW (P = 0.35) and BCS (P = 0.79); however, cows housed in muddy conditions had lesser BW (P < 0.01) and BCS (P < 0.01) at day 269 compared with CON cows, while there were no dry matter refusals from any animals throughout the study. Therefore, MUD cows weighed 37.6 kg less than CON cows by the end of the study while dry matter intake was the same between treatments, indicating that mud greatly increased cow requirements. more...

The intestine plays a crucial role in nutrient digestion and absorption, and its function is critical for animal growth and health. However, the effect of maternal nutrition on offspring’s intestine is not well documented. The objective of this study was to evaluate the effect of supplementing polyunsaturated fatty acids (PUFA), methionine (M) or both to ewes during late gestation on offspring duodenal amino acid (AA) and peptides transporters. Twenty-four post-weaned lambs (6/treatment) born from ewes supplemented from day 100 (d100) gestation until lambing were used. Dam supplementation was: 1) no PUFA or M supplementation (CONT, NFA-NM); 2) supplementation with PUFA (PUFA-NM, 1 % StrataG113); 3) a source of M (NFA-MET, 0.1 % rumen protected methionine, Smartamine); and 4) PUFA and MET (PUFA-MET). At weaning (60 days of age) lambs were placed in 24 pens and fed a common finishing diet for 56 days. On d56, lambs were harvested and samples of the duodenum were collected to quantified amino acid (AA) and peptides transporters. Protein quantification of amino acid transporters was performed using Simple Western System. Offspring data was analyzed as a 2x2x2 factorial (FA, M, and sex). No triple interaction was found (P > 0.15). Dam supplementation did not affect SLC38A2 and SLC38A10 expression. A trend was observed in MET*Sex interaction (P = 0.1), M-ewes and NM-wethers had a greater SLC6A19 expression compared with NM-ewes and M-wethers. Furthermore, SLC7A5 protein expression tended to decrease (P = 0.1) in M-ewes and NM-wethers when compared with M-wethers. There was an effect of FA supplementation, PUFA born animals had a greater SLC38A1 protein expression when compared to NFA born offspring. Maternal supplementation of M or PUFA led to a modification in the protein expression of duodenal AA transporters, and this modification could be influenced by the sex of the offspring. more...

The objective of this study was to evaluate the effect of supplementing polyunsaturated fatty acids (PUFA), methionine (M) or both to ewes during late gestation on offspring growth, dry matter intake (DMI), carcass composition, and glucose and insulin metabolism (by conducting a glucose tolerance test (GTT)). Seventy-two post-weaned lambs (6 pens/treatment, 3 lambs/pen) born from ewes supplemented from gestation day 100 until lambing were used. Dam supplementation was: 1) no PUFA nor M supplementation (NFA-NM); 2) supplementation with PUFA (PUFA-NM, 1 % StrataG113); 3) supplementation with M (NFA-MET, 0.1 % rumen protected methionine, Smartamine); and 4) supplementation with PUFA and M (PUFA-MET). At weaning (60 days of age) lambs were fed a common finishing diet for 54 days, and DMI was measured daily. Lambs were weighed on weaning day (d0), d28, and d54. Twenty-four lambs (one per pen) were used for a GTT on d55. On d56, other 24 lambs were harvested for carcass characteristics measurements. Offspring data was analyzed as a 2x2x2 factorial (FA, M, and sex). Ewe supplementation affected (P < 0.1) lamb DMI. On d54 lambs born from No FA and methionine showed a greater DMI. There was a tendency for plasma glucose concentration for PUFA*MET*Time (P = 0.07) in the GGT. Lambs born from ewes supplemented with methionine had greater glucose concentration than NFA-NM born lambs, and lambs born from PUFA*MET had greater glucose concentration than the other lambs at 2m of the GGT. Dam MET supplementation decreased lamb’s insulin response (P = 0.06). Hot carcass weight (HCW) (P = 0.08) and Ribeye area (REA) (P = 0.02) were affected by treatment and sex. A tendency and a triple interaction FA*MET*Sex were observed; NFA-MET methionine had a greater HCW and a larger REA. In conclusion, lamb’s insulin response and carcass characteristics are affected by dam’s supplementation. more...

The aim of this study was to evaluate the effect of weaning preconditioning and parenteral supplementation of minerals and vitamin on growth and plasma total antioxidant status (TAS), glucose, NEFA, and insulin concentrations, in calves at feedlot arrival. Sixty male Angus-cross calves were randomly assigned to 4 treatments (n=15/treatment). Treatments were arranged in a 2x2 factorial design; the main factors were mineral and vitamins supplementation (supplementation (S) vs no supplementation (NS)), and preconditioning (preconditioning (P) vs. not (NP)). Supplementation was applied subcutaneously on d -45, -26 and 0 and provided Cu, Mn, Se, Zn, and vitamins A and E (Adaptador Min-Vit ®, Biogénesis Bagó). Preconditioning consisted in a 26-day period between weaning and transportation at feedlot (d0) with the animals remaining in the same location. Blood samples were collected on d -26, 0 and 15. Animals were weighted on d-45, -26, 0, 8, 15 and 29. On d0 calves were load into a truck and drove for 5-hours to the feedlot. Data were analyzed using a mixed model as a 2x2 factorial, using repeated measurements. Body weight was greater on d 0, 8 15 and 29 group on groups NP, followed by S-P, and the lowest for NS-P (Triple interaction P < 0.01). Treatment did not affect (P ˃ 0.1) plasma insulin and glucose concentrations. There was a triple interaction (P < 0.08) for plasma TAS and NEFA concentration. Plasma TAS concentration was grater due to a decrease in its concentration for the S-P and NS-NP from d0 to d8, but not in the other treatments. Plasma NEFA concentration had the greater increase in the NP groups followed by S-NP on d0. In conclusion, 26-days precondition weaning decrease body weight compare with a traditional weaning. Mineral and vitamin supplementation in precondition weaning partially reduced that effect more...

Background Omega-3 PUFA or methionine (Met) supply during gestation alters offspring physiology. However, the effect of both nutrients on fetal development has not been explored. Our objective was to determine the effects of supplementation of these two nutrients during late gestation on fetal growth, DNA methylation, and mRNA expression of genes associated with the inflammatory response, and DNA methylation. Ewes (n = 5/treatment) were fed from day 100 to 145 of gestation one of the following treatments: 1) basal diet (NS) without fatty acids (FS) or methionine (MS) supplementation; 2) FS (10 g/kg Ca salts, source omega-3 PUFA); 3) MS (1 g/kg rumen protected methionine); and 4) FS and MS (FS-MS). On day 145, ewes were euthanized, and data from dams and fetus was recorded. Placenta (cotyledon), fetal liver, and blood samples were collected. Results A treatments interaction on fetal liver weight, ewe body weight and body condition score (BCS) was observed; FS-MS were heavier (P P = 0.02) BCS than NS. Methionine increased (P = 0.03) ewe plasma glucose concentration. Fetal liver global DNA methylation increased (P P = 0.04) the mRNA relative expression of arachidonate-5-lipoxygenase-activating-protein and tended to decrease (P = 0.06) methionine-adenosyltransferase-1A. Moreover, MS decreased (P = 0.04) DNA-methyltransferase-1 and tended to decrease (P = 0.08) free-fatty-acid-receptor-1 mRNA relative expression. Furthermore, FS-MS decreased mRNA relative expression of tumor-necrosis-factor-alpha (P = 0.05), peroxisome-proliferator-activated-receptor-delta (P = 0.03) and gamma (P = 0.04), tended to decrease (P ≤ 0.09) interleukin-6, fatty-acid-transport-protein-1, and delta-5-desaturase, and increased adenosylhomocysteinase (P = 0.04) mRNA relative expression. In cotyledon, FS tended to decrease fatty acid binding protein 4 (P = 0.09) mRNA relative expression. Conclusion Omega-3 PUFA and Met supplementation improves dam’s performance in late gestation, which was positively correlated with an increase in offspring’s liver development. Moreover, FS-MS decreased mRNA relative expression of proinflammatory cytokines, and lipogenic genes, and increased the expression on an enzyme that has an important role in methylation. more...

The objectives of this trial were to evaluate the effect of corn processing during the finishing phase on feedlot cattle performance and carcass characteristics. We hypothesized that steers fed dry-rolled corn would have better feed efficiency (less feed necessary to the same amount of gain) than steers fed whole shelled corn. Ninety-five backgrounded Angus-cross cattle (initial body weight [BW] = 263 ± 9.8 kg) were used in a randomized complete block design in a feedlot setting. Cattle were divided in to 3 blocks: heifers (n = 31, 4 pens; initial BW = 267 ± 1.3 kg), light steers (n = 32, 4 pens; initial BW = 253 ± 1.3 kg), and heavy steers (n = 32, 4 pens; initial BW = 279 ± 1.4 kg). Diets contained 70% corn (experimental treatment), 15% dried distiller’s grains with solubles, 7% grass hay, and 8% supplement, on a dry matter basis. Cattle were fed for 217, 224, and 231 ± 8 d for the heifer, heavy steer, and light steer blocks, respectively. Two pens within each block were randomly assigned to one of the following treatments: (1) dry-rolled corn (DRC) or (2) whole-shelled corn (WSC). Animal growth performance and carcass characteristics were analyzed using the MIXED procedure of SAS, including the fixed effect of treatment. Pen and block were included as random effects. Carcass characteristics USDA Yield Grade and Quality Grade distributions were compared using the GLIMMIX procedure of using the same model than the growth performance data. Data are presented as LSMeans. Cattle fed DRC had greater average daily gain (ADG; P = 0.02) and final BW (P < 0.01) when compared with cattle fed WSC. Even though ADG was greater for the DRC treatment, feed efficiency was similar (P = 0.45) because dry matter intake was also greater (P = 0.04) for DRC when compared with the WSC treatment. Cattle fed DRC also had greater hot carcass weight (P < 0.01), dressing percentage (P < 0.01), and Longissimus dorsi muscle area (P < 0.01) than cattle fed WSC. No differences (P ≥ 0.18) were observed for marbling score, USDA Yield Grade or USDA Quality Grade. In conclusion, feeding DRC to feedlot cattle improved ADG, hot carcass weight, and Longissimus dorsi muscle area, without affecting feed efficiency or meat quality. more...

Weaning and transport represent a high stress time for calves. Preconditioning (PC) by weaning before the transport separate these stressors. The stressors generate oxidative stress, which can be reduced by mineral and vitamin supplementation (MVS) with an antioxidant capacity. Our objective was to evaluate the effect of PC and MVS on performance of steers. The experiment used a 2 × 2 factorial arrangement design, considering a 26-d PC treatment from weaning to transport to the feedlot (day 0), and injectable MVS on days -45, -26, and 0. The MVS consisted of Cu, Zn, Mn, Se, vitamin E (0.2, 0.8, 0.2, 0.1, and 1 mg/kg body weight [BW], respectively), and vitamin A (1,190 IU/kg). Sixty Angus-crossbred steers (186.4 ± 27.6 kg) were randomly assigned to the four treatments (MVS+PC; N+PC; MVS+N; N+N; n = 15 per treatment). BW was recorded on days -45, -26, 0, 8, 15, and 29. On day 0, an additional BW was taken 30 min after the 5-h transportation (day 0.5). Between days 0 and 29, dry matter intake (DMI) and average daily gain (ADG) to DMI ratio (G:F) were measured. Between days -26 and 29 plasma concentrations of glucose, nonesterified fatty acids (NEFA), cortisol, insulin, total antioxidant status (TAS), and thiobarbituric acid-reactive substances were evaluated. Data were analyzed using the MIXED procedure of SAS with repeated measures, using treatment, time, and treatment × time as fixed effects and steer as a random effect. Between days -26 and 0, there was an interaction of MVS × PC (P ˂ 0.01) for ADG. From days -26 to 0, N+N and N+PC had the greatest and lesser ADG, respectively. On day 0.5, no-PC steers tended to lose BW, whereas the PC steers tended to gain BW (P = 0.09). In the period days 0 to 8, there were no differences (P ≥ 0.27) in DMI, but the PC steers had greater G:F and ADG (P < 0.01) compared with no-PC steers. Plasma NEFA concentration on day 0 was affected by MVS × PC (P < 0.01) because MVS decreased plasma NEFA concentration in no-PC steers, but it increased in the PC steers. Plasma concentrations of glucose, insulin, and cortisol did not differ among treatments (P ≥ 0.23). There was an MVS × PC interaction (P = 0.09) for TAS on day 0; N+N had the greatest TAS concentrations and MVS+N had the lowest TAS concentrations. In conclusion, a 26-d PC decreased steers BW compared with no-PC steers. The BW loss during PC was not recovered 29 d after feedlot entry. Despite this BW loss, MVS treatment decreased BW loss in the steers allocated to PC treatment on the day of transport., Facultad de Ciencias Veterinarias more...

Increased intestinal permeability can be observed during the physiologic stress response and has been linked to suppression of animal health and performance. Previously published data have shown the efficacy of fluorescein isothiocyanate dextran (FITC-d; 4.17 mg/kg) as a marker of enteric inflammation and mucosal barrier function in multiple species. Fluorescein is a smaller, less expensive alternative molecule possessing similar properties. The following two experiments compared FITC-d and fluorescein as potential indicators of intestinal permeability in pre- and postweaned lambs administered daily intramuscular injections of dexamethasone (Dex; 0.1 mg/kg) for 1 wk. Experiment 1 consisted of five preweaned lambs that were placed in one of two treatment groups: fluorescein with Dex (F+Dex) or fluorescein only (F). On day 7, blood was collected before and 1 h after oral administration of fluorescein (50 mg/kg). Experiment 2 included 12 weaned lambs and four treatment groups: F+Dex, F, FITC-d with Dex (Fd+Dex), and FITC-d only (Fd). On day 7, blood was collected before and 2 h after oral administration of FITC-d (4.17 mg/kg) or fluorescein (50 mg/kg). Plasma fluorescence was reported as the ratio between T1h/T0 or T2h/T0 for experiment 1 or 2, respectively. Experiment 1 showed a significant increase in T1h/T0 ratio of F+Dex relative to F lambs (P = 0.05) indicative of increased leaky gut; however, no differences (P = 0.22) were obtained in experiment 2. Results of these experiments suggest fluorescein may serve as a suitable marker of enteric permeability in preruminant lambs, but not in those with functional rumens. more...

The objective of the present study was to assess the association of prepartum lying time (LT) and the coefficient of variation (CV) of LT within 7 d before calving with prepartum serum nonesterified fatty acid (NEFA) concentration at 7 ± 3 d prepartum (dpp) and stillbirth. Prepartum pregnant Holstein heifers and cows from 3 dairy herds were used (n = 1,044). Animals were housed in freestall barns using a prepartum pen 21 d before the expected calving date and were moved into a contiguous maternity pen at parturition. Monthly, cohorts of 20 to 36 animals (heifers and cows combined) were enrolled at each farm and electronic data loggers (IceQube, IceRobotics, Edinburgh, UK) were fitted to the hind leg of individual animals to assess their behavioral activity. Stillbirth was defined as a calf born dead or died during the first 24 h after parturition in dams with normal gestation length. The LT was recorded for the last 7 dpp to assess differences among dams with stillbirth versus those with a calf born alive. Mean LT within 7 d before blood NEFA collection was assessed to determine the association with prepartum serum NEFA at 7 ± 3 dpp. Blood samples for the assessment of serum NEFA concentration were collected from prepartum animals at 14 ± 3 and at 7 ± 3 dpp. Blood samples for total serum calcium concentration were collected from postpartum cows within 48 h after parturition to assess differences among cows with stillbirth versus those with a calf born alive. Data were analyzed using CORR, MIXED, or GLIMMIX procedures of SAS (SAS Institute Inc., Cary, NC). Dams experiencing dystocic births had a greater proportion of stillbirth, but herd, parity, and season did not have an effect. Dams with a stillborn calf had reduced LT and increased CV of LT within the last 7 dpp compared with dams with a calf born alive, regardless of parity. Multiparous cows with a stillborn calf had higher prepartum serum NEFA concentration compared with multiparous cows with a calf born alive, but this did not differ for first-calf heifers. Regardless of parity, the proportion of postpartum cows with hypocalcemia was higher for dams with a stillborn calf compared with those with a calf born alive. Regardless of parity, LT of prepartum dams was strongly correlated with the CV of LT (as LT increased, the CV decreased), and prepartum dams with a mean LT between 11 and 15 h/d had the lowest serum NEFA concentration compared with dams with LT of 8 to 10 or >16 h/d. Serum NEFA concentrations at 7 ± 3 dpp was positively correlated with the CV of LT within 7 d before blood sample. These results show that the dam's prepartum LT and its consistency over time are associated with prepartum serum NEFA and calf survival at calving. more...

Our objective was to conduct a systematic literature review and collate data to run a meta-regression on the effect of protein and energy restriction during the last third of gestation on offspring growth and carcass characteristics. The literature search was restricted to only using data from the last third of gestation in spring calving herds such that the last trimester coincided with winter months. Additionally, the search was limited to Bos taurus beef cattle and peer reviewed research articles; review articles and proceeding abstracts/papers were excluded. The search was conducted using the Web of Science. During this process we found contradictory results. As an example, some manuscripts indicate that energy and/or protein restriction during late gestation has a negative impact on offspring growth and/or carcass characteristics; however, there are also manuscripts that report no differences in similar growth and carcass variables (Table 1). Also, most of the studies reported no differences with maternal restriction on offspring body weight at calving and at weaning. One of the limitations in the data set is that most articles did not measure or report dry matter, net energy, or crude protein intake on the dam; therefore, making it difficult to predict the severity of maternal nutrient restriction and the effects on the offspring. Because of this gap in the literature, we suggest that net energy and crude protein intake should be reported in future studies to better determine the effects of maternal restriction during late gestation on offspring growth and carcass characteristics. more...

The objective of this experiment was to evaluate the inclusion of a rumen-protected carbohydrate (RPC) on growth performance and blood metabolites of finishing steers during the summer. A 62-d feedlot study was conducted using 135 Angus crossbred steers (body weight = 287 ± 13 kg). All animals were fed a basal diet (BD), then treatments were top-dressed. The treatments were the same composition and only varied in ruminal degradability. Treatments were 1) a BD with 1 kg/d of a control supplement (0RPC), 2) the BD plus 0.5 kg/d of the control supplement and 0.5 kg/d of RPC (0.5RCP), and 3) the BD with 1 kg/d of RPC supplement (1RPC). Temperature humidity index and cattle panting scores (CPS) were measured daily during the experiment. Growth performance, back-fat over the 12th rib (BF), LM area, blood glucose and plasma insulin, urea, and nonesterified fatty acid concentrations were measured. Data were statistically analyzed (PROC Mixed, SAS) using treatment, time, and their interaction as a fixed variable and pen as a random variable. There were no differences (P > 0.10) between the three treatments on CPS, BF, and LM area on day 62. There was a trend (P = 0.06) for treatment effect for a greater body weight on the 0.5RPC, and a treatment effect for dry matter intake (P = 0.05). Treatment × day interactions were observed for average daily gain (ADG, P =0.04), suggesting a different response to treatments during the different sampling periods. There was a treatment effect for blood glucose concentration (P = 0.03), having the 0RPC the greatest concentration. Treatment × day interactions were found for plasma insulin concentration (P = 0.01). The results suggest that the response to RPC supplementation depends in part on environment. The use of 0.5 kg/d of RPC tends to improve overall body weight; however, the response to RPC on ADG and plasma insulin concentration depend on the time of sampling. more...

The objectives of this study were to evaluate the effect of feeding an enriched diet with eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) to finishing lambs born from ewes supplemented either with or without EPA and DHA during late gestation on productive performance, muscle fatty acid (FA), and hypothalamus mRNA concentration of metabolic genes and hormone receptors. Lambs born from dams fed during the last 50 d of gestation either with a control diet containing 0.39% Ca salts of palmitic fatty acid distillate (C) or Ca salts enriched with EPA and DHA (PFA) were used. After weaning lambs (n = 70) were blocked by weight (BW) and used in a 2 × 2 factorial into 2 finishing diets containing 1.5% of C or PFA. The 2 factors were the ewe diet and the finishing diet. Lambs (37.9 ± 0.4 kg) were weighed and blood sampled for glucose and NEFA measurements at days 1, 14, 28, and 42. Dry matter intake (DMI) was measured daily. At day 43, 14 females and 14 males were slaughtered, and hot carcass weight, body wall thickness, rib eye area, and FA composition of Longissumus thoracis muscle were evaluated. Female hypothalamuses were obtained and mRNA concentration of hormone receptors, neuropeptides, and their receptors was measured. Lambs born from PFA dams were heavier (P 0.1). Lambs born from PFA dams had a greater concentration of C22:0 (P < 0.03). Lambs fed C had higher concentrations of C18:1c15 (P < 0.01), C17:0 (P < 0.09), C18:0 (P < 0.09), and n6/n3 (P < 0.01). Lambs fed PFA had greater concentration (P < 0.05) of C16:1, C22:1, C20:5, C22:5, C22:6, total n3 FA, and total EPA and DHA. There was a significant dam × finishing diet interaction (P ≤ 0.08) on mRNA concentration for MCR3, CCK-R, Cort-R, and CART. Lambs, which had the same treatment as their dams, showed lower overall mRNA concentration than those with different treatments between them and their dams. Lambs born from PFA ewes had lower concentration of MCR4 mRNA (P = 0.09) than C. Agouti-related peptides mRNA concentration was lower in lambs fed PFA (P = 0.06) than C. In conclusion, changes on lamb performance, muscle fatty acid composition, and metabolic neuropeptides depend not only on the lamb diet, but also on the dam diet during late gestation. more...