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Chews are an important part of the pet product industry, with many having potential to decrease plaque or calculus formation. However, their digestion characteristics and gut transit time are virtually unknown. Two experiments were conducted to determine in vitro DM digestibility of expanded pork skin chews and rawhide chews, and apparent total tract digestibility (ATTD), gastrointestinal transit time, and blood metabolite measurements in healthy adult dogs fed a weight-control commercial diet and expanded pork skin chews. In Exp.1, an in vitro method that simulated gastric and small intestinal digestion was used to determine DM digestibility of expanded pork skin chews and rawhide chews. In Exp. 2, after a 22-d baseline phase, 10 purpose-bred, intact female dogs (5 to 5.5 yr of age; 18.9 to 23.1 kg BW) were fed the diet plus an expanded pork skin chew (~45 g) each day for 22 d. In vitro gastric digestibility of expanded pork skin chews increased with time, with chews being 54.7%, 58.6%, 76.4%, and 86.4% digestible after 6, 12, 18, and 24 h of gastric digestion, respectively. By contrast, gastric digestibility of rawhide chews was 7.6% at 6 h, slowly increased over time, and reached a maximum of 41.6% at 18 h. In vitro gastric plus small intestinal digestibility results indicated near complete digestibility of expanded pork skin chews at all times, whereas rawhide chews were 50 to 85% digestible. In vivo ATTD of DM, OM, and N were greater (P < 0.05) when dogs were fed expanded pork skin chews along with the basal diet, compared with the basal diet alone. However, chew intake did not change transit time measured with a wireless motility device. By contrast, motility index and contraction pattern of the colon were altered (P < 0.05) during chew feeding relative to control. Blood urea N concentrations were greater (P < 0.05) in dogs fed expanded pork skin chews, compared with baseline; this was not surprising, given the increased N intake and absorption from the chews. Intake of expanded pork skin chews resulted in reduced blood cholesterol concentrations (P < 0.05) and tended to decrease blood triglyceride concentrations (P < 0.10). Expanded pork skin had a greater DM digestibility than rawhide chews. In addition, expanded pork skin decreased blood cholesterol and triglyceride concentrations, which may justify further research in this area.

Feeding different levels of dried distillers grains with solubles (DDGS) to sows may affect the fatty acid profile and quality of final sausage products such as bratwurst. The purpose of this study was to determine the differences in quality of bratwurst made from sows fed different combinations of DDGS with or without Gromega. The 4 dietary treatments were as follows: control (CON), control plus DDGS (CON+DDGS), control plus Gromega (CONGROW), or control and Gromega plus DDGS (CONGROW+DDGS). For the DDGS treatments, 30% DDGS was fed during gestation, followed by 15% during lactation. Both initial appearance and cooked scores of bratwurst were determined. Fresh appearance of bratwurst was based on a 1 to 4 scale (1 = lowest and 4 = highest), plus an unacceptable product (UP). Only the CON+DDGS was lower (P ≤ 0.01) in fresh appearance when compared with all other fresh bratwurst. The CONGROW+DDGS bratwurst had a higher overall cooked quality (P ≤ 0.02) and taste score (P ≤ 0.01) compared with all other bratwurst treatments. Bratwurst fatty acid profiles differed among treatments. The concentration of linoleic acid was greatest (P ≤ 0.0001) in the CONGROW+DDGS, followed by the CON+DDGS group, with both treatments without DDGS being lowest. The highest (P ≤ 0.0001) calculated iodine value was observed in the CON+DDGS (65.6), followed by CONGROW+DDGS (59.7), with the lowest being the 2 non-DDGS diets [53.1 (CON) and 55.9 (CONGROW)]. In summary, differences were observed in DDGS feeding of sows, and Gromega apparently enhanced overall bratwurst quality.

The purpose of this study was to test an educational swine curriculum geared toward fifth grade classrooms to measure the change in students’ knowledge about the pork industry, pork as a nutritious protein source, and the value of byproducts derived from pork production. Objectives of this study were to evaluate overall change in students’ knowledge of the pork industry and the effect of specific demographics on the change in students’ knowledge following participation in an educational swine curriculum. Effectiveness of the curriculum was measured by a pretest/post-test survey of fifth grade students (n = 435), with classrooms divided into treatment and control groups. Findings indicated that participating in the educational swine curriculum increased the students’ knowledge of the pork industry by 37.4%; demographics such as 4-H experience, farm experience, or prior experience with pigs had limited effect on knowledge gained.

Previous work in our laboratory showed that including 125 ppm of l -carnitine in the diets of roosters increased sperm concentration. The objective of this experiment was to determine whether reproductive efficiency could be improved by feeding l -carnitine to both parents over that of feeding l -carnitine to only the male or female. Diets formulated to contain 0 or 125 ppm of l -carnitine were fed to male and female birds from hatch until 37 wk of age. Eighty-four roosters were used, with the semen of 2 roosters constituting an experimental unit. Pools of semen from either l -carnitine-supplemented or control roosters were artificially inseminated into each of 288 hens with 23.5 μL of semen at weekly intervals, in a 2 × 2 factorial arrangement, resulting in a mean insemination dose of 1.2 and 1.1 × 108 sperm/hen for l -carnitine and control hens, respectively. Dietary l -carnitine, as compared with the control diet, increased egg yolk l -carnitine concentration (P = 0.001), decreased hatchling yolk sac weights (P = 0.0001), decreased yolk sac lipid content at hatch (P = 0.01), and culminated in compositional changes of yolk fatty acids, but it did not affect hatch rate, egg production, and egg traits. Although supplementing diets with l -carnitine improved sperm concentration, it did not result in a subsequent improvement in hatch rate, most likely because of the high numbers of sperm that were inseminated artificially in both the control and l -carnitine-supplemented hens. The higher concentrations of l -carnitine in the yolk of hatching eggs obtained from hens consuming l -carnitine as compared with controls may have encouraged the utilization of fat by developing embryos, as indicated by the decreased hatchling yolk sac weights and yolk sac lipid content, perhaps leading to the selective utilization of linoleic (C18:2n-6) and α-linolenic (C18:3n-3) acids for growth and development over myristic (C14:0) and oleic (C18:1n-9) acids.

The objective of this study was to determine the effect of conjugated linoleic acid (CLA) and tallow on belly firmness in 120 gilt finishing pigs. Pigs were assigned to 1 of 5 treatment combinations and fed 30 d prior to slaughter. Treatments were as follows: control, a 5% restaurant grease for 30 d (RG30); 5% restaurant grease for 0 to 20 d and switched to CLA (0.83%) and restaurant grease (4.17%) combination for 20 to 30 d (RGCLA); 5% restaurant grease for 0 to 20 d and switched to a 5% tallow for 20 to 30 d (Tallow10); 5% restaurant grease for 0 to 10 d and switched to a 5% tallow for final 20 d (Tallow20); and 5% tallow for 0 to 30 d (Tallow30). No changes occurred in drip loss, pH, loin eye color, or size, and no difference occurred in growth parameters, except for ADG between 20 to 29 d, where pigs allotted to Tallow20 and Tallow30 had greater (P

The purpose of this study was to examine growth and carcass changes in cull gilts (n = 12 animals which had not conceived) when fed exclusively either ground corn or distillers dried grains with solubles (DDGS) for 14 d. There were significant changes between the 2 treatments in terms of feed consumption and growth. Over the 14-d period, the ground corn group consumed 342.5 kg whereas the DDGS group consumed 93.4 kg. At d 14, the average BW of the ground corn fed pigs was greater (P ≤ 0.05) compared with DDGS fed gilts. Carcass cuts were compared between treatments and only relative picnic weight (picnic/hot carcass weight) was greater (P ≤ 0.005) compared with ground corn treated animals. Subjective evaluation of bratwurst from the DDGS fed group appeared smeary compared with bratwurst in the corn fed group. The ratio of saturated:unsaturated fat of bratwurst was less (P ≤ 0.04) in the DDGS treatment (0.59) than in the corn treatment (0.62). Arachidonic (C20:4n6) concentration was less (P ≤ 0.01) in the bratwurst from animals on the corn treatment (0.17) than those on the DDGS treatment (0.31). In summary, feeding exclusively DDGS altered feed consumption, final BW, and lipid fatty acid composition of bratwurst

In Experiment 1, fatty acid distribution of bratwurst (n = 14 different brands) were investigated from products purchased from various retail stores. In Experiment 2, sows were fed a control diet (n = 5) or a diet enriched with FertiliumTM. (United Feeds, Sheridan, IN) (n = 5), a fertility supplement with high levels of Omega n3 fat, to investigate the fatty acid profile in the middle and outer fat layers. Results of Experiment 1 suggest that major fatty acids [C16:0, C18:0, C18:2, as well as the n6:n3 ratio and iodine value (IV)] varied significantly (P

The purpose of this study was to determine if playing hen calls at the feeder affects broiler chick productivity and welfare. Hatched chicks (n = 832) were equally placed into 16 pens. Broilers in 8 treated pens received 3 min of hen-feeding calls once each hour during the first 9 d of age; broilers in the other 8 pens received no recorded hen vocalizations during the same period. After d 9, recorded hen vocalizations ceased and all birds were treated identically. Through 9 d of age, chicks receiving recorded hen vocalizations had improved (P < or = 0.05) feed conversion ratios, and these chicks weighed more (139.12+/-1.52 g vs. 133.17+/-1.59 g for control chicks; P < or = 0.01). The behavior data showed that on d 1, 4, and 7, more (P < or = 0.05) chicks receiving recorded hen vocalizations were found within 0.61 m of the speaker than control chicks. Following recorded hen vocalization cessation on d 9, birds and feed were weighed on 17, 24, 31, and 38 d of age, and carcass yield was measured on d 40. There were no differences in BW, feed efficiency, or carcass yield after recorded hen vocalization ceased. These data suggest that after d 9, differences became nonsignificant, corresponding to when recorded hen vocalization stopped. Behavior data demonstrated that chicks appear to be attracted when stimulated with recorded hen vocalizations, thus remaining in close proximity to the speaker. Evidence suggests that hen vocalization improves production and attraction to hen vocalization with known improvements in BW and feed conversion during the first 9 d posthatch.

Blood lipid and lipoprotein concentrations were measured and compared between euthyroid and thyroidectomized mares on low-fat or high-fat diets to test the hypothesis that hypothyroidism alters the blood lipid response to higher dietary fat intake. Four healthy adult mares and four adult mares that had been thyroidectomized 3 to 6 mo earlier were placed on low-fat or high-fat diets according to a replicated 2 x 2 Latin square design consisting of two 5-wk feeding periods separated by a 2-wk washout interval. Plasma lipid concentrations were measured at 0, 3, 4, and 5 wk, and plasma lipase activities were measured at the end of each 5-wk feeding period. Compared with euthyroid mares (0.46 ng/mL [range 0.34 to 0.68 ng/mL T3], and 21.5 ng/mL [range 18.1 to 25.1 ng/mL T4], respectively), median serum concentrations of T3 and T4 were lower (P = 0.029 and P = 0.021, respectively) in thyroid-ectomized mares (0.26 ng/mL [range 0.23 to 0.26 ng/ mL T3], and undetectable T4). Serum T4 concentrations were below the limits of detection in thyroidectomized horses. Alterations in body weight over 5 wk did not differ between groups. Mean plasma very low density lipoprotein (VLDL) and triglyceride (TG) concentrations were higher (P = 0.045 and 0.034, respectively) in hypothyroid mares (55.42 +/- 35.05 mg/dL and 52.83 +/- 34.46 mg/dL, respectively) compared with euthyroid mares (28.28 +/- 13.76 mg/dL and 23.53 +/- 9.84 mg/dL, respectively). Mean plasma total cholesterol (TC) concentrations increased from 88.73 +/- 25.49 mg/dL at baseline to 103.93 +/- 24.42 mg/dL after 5 wk on the low-fat diet, but increased by a greater magnitude (P = 0.006 diet +/- time interaction) in mares that were on the high-fat diet (81.05 +/- 17.24 mg/dL and 123.84 +/- 32.27 mg/ dL, respectively). Mean plasma TC concentrations were higher (P = 0.099) in hypothyroid mares (116.16 +/- 32.89 mg/dL) than in euthyroid mares (89.56 +/- 14.45 mg/ dL). Higher post-heparin plasma lipoprotein lipase and hepatic lipase activities (P = 0.012 andP = 0.017, respectively) were detected in mares that were on the high-fat diet (2.66 +/- 0.91 micromol FA x mL(-1) x h(-1) and 2.95 +/- 0.49 micromol FA x mL(-1) x h(-1), respectively) vs. a low-fat diet (1.75 +/- 0.55 micromol FA x mL(-1) x h(-1) and 2.27 +/- 0.59 micromol FA x mL(-1) x h(-1), respectively). We conclude that plasma VLDL and TG concentrations are elevated in hypothyroid mares, but the blood lipid response to higher dietary fat intake is not influenced by hypothyroidism.

The purpose of the study was to determine the effectiveness of agricultural literacy materials designed for the Incubators in the Classroom program used in Indiana fourth grade classrooms. This article reports on the study objectives: determine the impact of the educational materials on fourth grade students’ and teachers’ knowledge level of agricultural professions and identify fourth grade students’ perceptions and opinions of agricultural careers and their possible career plans. Effectiveness of the educational materials was measured through a pretest-posttest research design on Indiana fourth grade school children (n=736) and their respective teachers (n=39). The sample of students and teachers was divided into treatment and control groups. Quantitative data were collected through questionnaires. The findings indicated the educational materials developed and assessed for this study were effective in increasing knowledge of agricultural professions among both the treatment group students and teachers. The treatment group students were significantly more likely to see agricultural careers as interesting and exciting.

Objective—To evaluate selected concentrations of blood lipids and lipase activities in euthyroid and hypothyroid horses deprived of feed for 96 hours. Animals—4 healthy adult mares and 4 thyroidectomized adult mares. Procedure—Horses were deprived of feed for 96 hours. Blood samples were collected at 24-hour intervals and analyzed to determine concentrations of nonesterified fatty acid (NEFA), triglyceride (TG), total cholesterol (TC), and very-low-density lipoprotein (VLDL) as well as composition of VLDL. Plasma lipase activities were measured after feed was withheld for 96 hours and 12 days after resumption of feeding. Results—Time significantly affected plasma NEFA, VLDL, TG, and TC concentrations in both groups of horses. During the 96-hour period, mean plasma concentrations of NEFA and VLDL increased 10-fold in euthyroid horses and increased 5-fold and 9-fold, respectively, in hypothyroid horses. Mean plasma TG concentrations increased 8-fold in both groups, and plasma TC concentrations significantly increased by 33 and 30%, respectively. Composition of VLDL was significantly affected by feed deprivation in euthyroid horses. Activities of lipoprotein lipase and hepatic lipase were significantly higher in feed-deprived horses. Activity of hepatic lipase was significantly lower in hypothyroid horses than in euthyroid horses. Conclusions and Clinical Relevance—Hypothyroidism did not significantly alter the magnitude of the response of blood lipids to feed deprivation. Thyroid hormones may reduce variability in blood lipid concentrations but do not determine susceptibility to hyperlipemia. Hypothyroidism does not appear to be a factor in the pathogenesis of hyperlipemia in horses. (Am J Vet Res 2003;64:823–828)

Institutions are currently seeking alternative ways to deliver a full-line of course materials without acquiring additional staffing. Hence, faculty is charged with creating alternative ways to deliver or offer course content to students. The purpose of this study was to evaluate undergraduate and graduate performance and perception of teleconferencing versus traditional blackboard lectures. In the undergraduate course, we discovered that students performed equally as well on exams and provided favorable reviews of the course; however, the acceptance of this new format is lacking given the enrollment and number of students dropping, e.g., 30 to 40% reduction in the course before semester's end. On the other hand, students taking the graduate course appear to accept the technology well with consistent enrollments and achievement in course content. In summary, using teleconferencing as a way to teach students may be better suited for graduate students when compared to undergraduates.

There are reports that age of broiler breeders and turkey breeders can influence offspring performance; however, there are no data to support such possibilities in the Pekin duck. The effects of breeder age (prepeak and postpeak egg production) on fertility and hatchability were evaluated. Additionally, after hatch the effects of breeder age on body weight gain, feed conversion rates, and mortality through 8 d of age were investigated. These data suggest that prepeak breeders (24 wk of age) exhibit lower levels of fertility and reduced hatch of fertile eggs. In addition, ducklings from prepeak breeders display lower body weight gains and higher mortality rates when compared to their counterpart hatched from peak or postpeak breeders.

Beginning at 22 wk of age, broiler breeder hens were fed one of six experimental diets. Diets 1 and 2 were fed to provide each bird an ME intake of 467 kcal/day (high) at peak production [467 peak Calories/day (PCD)], whereas Diets 3 and 4 contained low ME levels (430 PCD), and Diets 5 and 6 contained moderate ME levels (449 PCD). Diets 1 and 3 contained 3.0% added poultry fat, Diets 2 and 4 contained no added fat, Diet 5 contained 1.5% added poultry fat, and Diet 6 contained 3.0% added corn oil. Eggs were collected when hens were 29 wk of age. Embryonic mortality, hatchability, and subsequent growout performance were assessed through 42 d of broiler age. Added fat type (poultry fat or corn oil), poultry fat level (1.5 or 3.0%), or ME level from low (430 PCD) to high (467 PCD) in the diets of young (29-wk-old) breeder hens had no effects on subsequent embryogenesis, hatchability, or posthatch growout performance of broiler offspring. It was concluded that 1.5 and 3.0% added poultry fat or 3.0% added corn oil may be effectively used to adjustMEbetween low and high levels in the diets of young breeder hens without subsequent effects on broiler embryogenesis and growout performance.

The purpose of this study was to determine the effectiveness of agricultural literacy materials designed for the Incubators in the Classroom program used in Indiana fourth grade classrooms. The objectives were to determine the impact of these materials on the agriculture-related science concepts knowledge level of fourth grade students and the impact of these materials on the agriculture-related science concepts knowledge level of fourth grade teachers. Effectiveness of the educational materials was measured using a pretest-posttest research design with Indiana fourth grade school children (n=736) and their respective teachers (n=39). The sample of students and teachers was divided into experimental and control groups, then stratified based on community population size (less than 5,000, between 5,000-15,000, greater than 15,000). Quantitative data were collected through questionnaires. The data indicated the educational materials developed and assessed for this study were effective in increasing knowledge about agriculture-related science concepts among both the experimental students and teachers.

The effects of energy level, fat type, and fat level in breeder hen diets on subsequent offspring market age live BW, carcass yield, and liver characteristics from breeder hens at 29 and 36 wk of age were evaluated. At 22 wk of age, six dietary treatments were imposed. Dietary treatments contained: 1) 3.0%, added poultry fat (PF) and 467 (high energy) kcal/hen per day at peak production (CPP), 2) no added fat and high energy, 3) 3.0% added PF and 430 (low energy) CPP, 4) no added fat and low energy, 5) 1.5% added PF and 449 (moderate energy) CPP, and 6) 3.0% added corn oil (CO) and moderate energy. Breeder age influenced Day 43 broiler live BW, percentage total carcass and front-half yields, and liver moisture contents. Furthermore, wet and dry liver weights were higher in female broilers compared to those of male broilers from 29-wk-old breeder hens. Live BW was higher in broilers from hens fed low-energy diets compared with moderate-energy diets and 3.0% compared to 1.5% PF diets. Percentage liver DM was higher in females compared to male broilers from hens fed 3.0% CO and moderate energy and was highest in male and female broilers from hens fed 1.5% PF and moderate energy. Percentage wet liver weight and liver DM were higher and liver moisture content was lower in broilers from hens fed 1.5% compared to 3.0% PF diets. Overall, energy and fat levels in breeder diets had subsequent influences on market age weight and liver characteristics of broilers.

The purpose of this study was to investigate the effects of duck breeder age on circulating very low density lipoprotein (VLDL) and low-density lipoprotein (LDL) levels in embryonic (day 25 of incubation) and newly hatched ducklings (hatch and 1, 2, 3, and 5 days after hatch). In this study, embryos and ducklings from one breeder flock were monitored at breeder ages 24 weeks (young breeders), 31 weeks (mature breeders and near peak egg production), and 47 weeks (after peak egg production). Embryos and newly hatched ducklings from young breeders (24 weeks of age) displayed lower levels of VLDL and LDL. The composition of VLDL was affected by breeder age such that embryos and ducklings from young breeders had less cholesterol ester/protein and triglyceride/protein ratios. Even though the overall levels were suppressed in embryos and newly hatched ducklings from 24-week-old breeders, the overall percentage of triglyceride within VLDL and LDL particles was higher. These data would suggest that breeder age affects concentration and composition of both VLDL and LDL in embryos and newly hatched ducklings.

Latour, M.A., Peebles, E.D., Doyle, S.M. and Panskv, T. 2001. Effects of broiler breeder hen age and dietary fat intake on circulating serum lipids. J. Appl. Anim. Res., 19: 73–84. The purpose of this study was to evaluate the effects of diet and broiler breeder hen age on serum cholesterol (CHOL) and very low density (VLDL) and high density (HDL) lipoproteins. In Experiment 1, breeder hens were bled at 20, 26, 32, 36, 43 and 48 wk of age, whereas in Experiment 2 hens were bled at 22, 36, 51 and 69 wk of age. Across both experiments lipids changed drastically with the onset of lay and as the breeders aged. In Experiment 1, CHOL and HDL decreased at 32 wk and remained low through 48 wk when compared to prelay values at 20 wk. A similar pattern was observed in Experiment 2. In both experiments, VLDL increased greatly with the onset of egg production. Despite the alterations in diet (saturated vs unsaturated diets) there were no differences in circulating lipids as affected by diet. The present stud...

The effects of dietary fat and broiler breeder age on egg and embryo characteristics during incubation were investigated. Breeders were fed diets containing no added fat or 3.0% added poultry fat (PF) for peak energy intakes of 430 and 467 kcal/hen day (pC/d), or 1.5% PF or 3.0% corn oil at 449 pC/d. Feeding of diets was initiated at 22 wk, and eggs were collected for incubation at 27 and 36 wk of age. Percentage incubational egg weight loss was determined between day of set and Days 6, 12, and 18. Percentage wet and dry embryo weights, embryo moisture content, and eggshell weights were determined at 6, 12, and 18 d of incubation. Percentage yolk sac weight and wet and dry liver weights and moisture content were determined on Days 12 and 18. Percentage gall bladder weight was determined on Day 18. There were no observed effects due to breeder diet. However, eggshell weight at Days 6, 12, and 18 was higher in 27-wk-old hens compared with 36-wk-old hens. Conversely, egg weight loss between Day 0 and Days 6, 12, and 18 and yolk sac weight across Days 12 and 18 of incubation were lower in eggs at 27 wk of age compared with 36 wk. At Day 18, dry embryo weight was higher and wet liver weight was lower at 27 wk compared with 36 wk. A slower rate of DM accumulation in embryos at Week 36 compared to Week 27 was associated with increased incubational water loss and decreased embryo moisture content, eggshell percentage, and yolk sac absorption rate. These data demonstrate that changes in eggshell characteristics with broiler breeder age can alone impact yolk uptake, growth, and body composition in subsequent embryos.

The purpose of this study was to investigate the effects of duck breeder age on liver lipid accumulation and yolk absorption and utilization in duck embryos (day 25 of incubation) and newly hatched ducklings. One breeder flock was monitored at 24 (young breeders), 31 (mature breeders and near peak egg production) and 47 (post peak egg production) weeks of age. Electron microscopy images of duck embryo liver slices revealed a significant change in hepatic lipid accumulation as a function of breeder age. More specifically, as breeder age increased both the relative number of liver lipid droplets as well as the size of the lipid droplets increased in duck embryos (day 25 of incubation). At hatch, however, newly hatched ducklings from 31-week-old breeders exhibited the lowest number as well as the smallest sized lipid droplets when compared to ducklings from 24 or 47-week-old breeders. The trend in yolk absorption at day 25 as a function of breeder age paralleled that in liver lipid accumulation. That is, day 25 maintained a higher percentage of unabsorbed yolk when compared to embryos from 31- or 47-week-old breeders. In contrast to breeder age, time of incubation (day 25 vs. day 28 or hatch) had little effect on yolk fatty acid profiles when compared to breeder age. Although there were no clear trends in yolk fatty acid usage among the various ages of breeders, newly hatched ducklings from 31-week-old breeders did have a significantly higher proportion of 18:2 n6 compared to those from breeders at 24 or 47 weeks of age. These data would suggest that breeder age subsequently affects the relative number and size of liver lipid droplets in embryos and newly hatched ducklings.

Latour, M.A., Meunier, R.A., Huber, D. and Stallings, K. 2000. Ammoniated broiler diets reduce fecal phosphorus excretion. J. Appl. Anim. Res., 18: 91–95. To determine if diet ammoniation would alter the fecal characteristics of growing broilers during the last week of production, forty broiler chicks were raised on the same diet up to 28 days of age. On day 28 for two weeks, broilers were equally and randomly assigned to the following dietary treatments: (a) control or (b) control diet plus 3% added ammonia. Fecal samples were collected at day 28 and day 35 to assess any changes in composition. Across both treatment levels, the percentage of fecal calcium, sodium and potassium was reduced between day 28 and 35. Also, the percentage (7.3% reduction) in fecal phosphorus was reduced in broilers receiving the ammoniated diet. This study would suggest ammoniated diets reduce the level of fecal P in broilers during the last week of production.

The effects of breeder age and added dietary fat source and level on broiler hatching egg characteristics were evaluated. Diets included no added fat (NAF) or 3.0% added poultry fat (PF) for peak energy intakes of 430 and 467 kcal/hen-day (PCD) or 1.5% PF or 3.0% corn oil (CO) at 449 PCD. As added dietary fat was changed from CO to PF, the percentage of unsaturated dietary fatty acids, including linoleic acid, decreased. Feeding of experimental diets was initiated when breeders were 22 wk old. Total fresh egg weight; eggshell weight; percentages of yolk (PYK), albumen (PAB), and eggshell (PSHL) weights; and yolk:albumen ratio were measured at various weeks between 26 and 47 wk of age. Egg weight increased progressively with hen age. Significant increases in yolk:albumen ratio occurred between Weeks 26 and 31 and between Weeks 31 and 35. Low (430 PCD) dietary energy levels significantly reduced PYK at 35 wk and increased PAB across breeder age. Eggshell weight was lower in birds fed moderate (449 PCD) compared to low energy levels at Week 26, moderate compared to high (467 PCD) energy levels at Week 41, and PF compared to CO across fat level at Week 31. At Weeks 31 and 41, PSHL was increased by the use of 3.0% PF compared to 1.5%, and PSHL was increased at Weeks 26 and 41 by using added PF compared to CO across fat level. Increased dietary energy decreased PAB and the use of added dietary CO rather than PF decreased PSHL in broiler breeders between 26 and 47 wk of age.

The effects of breeder age (35, 51, and 63 wk) and added dietary fat on subsequent broiler slaughter yield were evaluated. Beginning at 22 wk of age, diets included 0, 1.5, or 3.0% added poultry fat (PF), 1.5 or 3.0% added corn oil (CO), or 3.0% added lard (LA). Slaughter yields were greatest in broilers from 63-wk-old breeders. Added CO in broiler breeder diets significantly increased subsequent 43-d live BW and chilled carcass yields compared to LA. Furthermore, CO diets significantly increased relative front-half yields compared to PF diets; and compared to the 3.0% fat level, 1.5% added fat significantly increased 43-d live BW, regardless of fat type. In conclusion, breeder age influenced broiler slaughter yield, and fat added at the 1.5% level to breeder hen diets was an effective energy source. However, less saturated fat improved subsequent slaughter yield.

Broiler breeder hens were fed isocaloric diets containing one of three different types and levels of added fat. Eggs collected when hens were 52 and 62 wk of age were either left intact or were washed to remove the eggshell cuticle prior to set. Chicks hatched from each breeder diet and eggshell cuticle treatment were reared through 22 days to assess effects on broiler performance. An increase in feed consumption in broilers from 52-wk-old breeders was associated with cuticle removal. It was concluded that eggshell cuticle removal in eggs from hens during post-peak production may lead to subsequent increases in feed consumption of broiler offspring.

Skeletal muscle atrophy results from an imbalance in protein degradation and protein synthesis and occurs in response to injury, various disease states, disuse, and normal aging. Current treatments for this debilitating condition are inadequate. More information about mechanisms involved in the onset and progression of muscle atrophy is necessary for development of more effective therapies. Here we show that expression of the mouse ether-a-go-go related gene (Merg1a) K+ channel is up-regulated in skeletal muscle of mice experiencing atrophy as a result of both malignant tumor expression and disuse. Further, ectopic expression of Merg1a in vivo induces atrophy in healthy wt-bearing mice, while expression of a dysfunctional Merg1a mutant suppresses atrophy in hindlimb-suspended mice. Treatment of hindlimb-suspended mice with astemizole, a known Merg1a channel blocker, inhibits atrophy in these animals. Importantly, in vivo expression of Merg1a in mouse skeletal muscle activates the ubiquitin proteasome pathway that is responsible for the majority of protein degradation that causes muscle atrophy, yet expression of a dysfunctional Merg1a mutant decreases levels of ubiquitin-proteasome proteolysis. Thus, expression of Merg1a likely initiates atrophy by activating ubiquitin-proteasome proteolysis. This gene and its product are potential targets for prevention and treatment of muscle atrophy.

The effects of lard added to starter diets on various serum lipids were determined in broiler chickens between 14 and 42 d of age. Nonisocaloric starter diets were formulated to contain either 0, 3, or 7% added lard, where the megacaloric percentages of all major nutrients were held constant. Birds received either 0, 3, or 7% added lard in starter diets through 10 d of age (S1), followed by either 3 or 7% added dietary lard through 21 d of age (S2). All possible combinations of the three S1 diets and two S2 diets yielded six total dietary treatments. A common grower diet was provided after 21 d. Concentrations of various serum lipids were determined weekly from 14 to 42 d of age. The effects of both the S1 and S2 diets on total cholesterol, low density lipoprotein cholesterol (LDLC), and high density lipoprotein cholesterol (HDLC) were inconsistent and were influenced by sex between 14 and 42 d of age. However, serum triglycerides and very low density lipoprotein cholesterol concentrations showed progressive increases over the 14 to 42 d period in birds that received dietary lard at either level in the S1 diet. These same serum constituents also increased to the greatest extents over the same period when birds were provided 3% added lard in the S2 diet. It was concluded that the response of broiler chickens between 14 and 42 d to different levels of dietary lard were influenced by age of feeding during the starter period. Furthermore, the specific effects of the diets on serum cholesterol, LDLC, and HDLC concentrations between 14 and 42 d varied with the sex and age of the bird.

Lard has become more available as a cheaper fat source for increasing the energy of broiler starter diets. Non-isocaloric starter diets were formulated to contain either 0, 3, or 7% added lard, with megacaloric percentages of all major nutrients held constant. Broilers received either 0, 3, or 7% added lard in starter diets to 10 days of age (S1), when they were changed to either 3 or 7% added lard starter diets (S2). At 21 days of age, all birds were changed to a common grower diet. Body weights (BW) and calorie conversions (CC) at 42 days of age were determined. Carcass yield was determined on day 44. Fat-free bone ash fat S1 diets increased BW in males and females. The S1 and S2 diets had no effect on CC, percentage fat pad and carcass yield increased in males. Lard added at the 3 or 7% levels to broiler starter diets between 11 and 21 days of age may be a cost-effective energy source with no adverse effect on 42-day BW and carcass fat at 44 days.

The purpose of this study was to characterize intestinal apolipoprotein B (apoB) metabolism in subjects with familial hypobetalipoproteinemia (FHBL), where segregation analysis supports linkage to the apoB gene but no apoB truncations are present. We investigated cholesterol and fat absorption, intestinal apoB mRNA synthesis and editing, as well as apoB-48 synthesis. Plasma triglycerides (TG) and retinyl palmitate in the chylomicron fractions were analyzed after 12 hours of fasting and then repeatedly for 14 hours after ingestion of a vitamin A—containing high-fat meal. Cholesterol absorption was assessed using a dual stable-isotope method. Mean peak times and concentrations and areas under the curve (AUCs) for fat absorption and mean percentages of cholesterol absorption were comparable in affected and nonaffected family members. Intestinal biopsies were extracted for total RNA and also incubated with 35 S -methionine for measurements of apoB synthesis. Similar quantities of apoB mRNA were found to be expressed in the intestine in affected and control subjects by RNase protection assay. ApoB mRNA editing assay showed that the majority of apoB-100 mRNA was edited to the apoB-48 form to a similar extent in both groups. Virtually no apoB-100 protein was synthesized by the intestine in any subject, and apoB-48 protein synthesis was not significantly different in the affected individuals. These data are consistent with in vivo metabolism data that show normal production rates for liver-derived apoB-100 but increased apoB-100 fractional catabolic rates in affected members of this family. Thus, the molecular defect probably does not affect transcription, translation, or secretion of apoB-containing lipoproteins, but may instead affect their clearance.

Familial hypobetalipoproteinemia (FHBL) exists in three forms: a) FHBL genetically linked to truncated forms of apolipoprotein B (apoB); b) FHBL linked to the apoB gene but with no apoB truncations; and c) FHBL not linked to the apoB gene. Mean production rate (PR) of apoB-100 in FHBL subjects heterozygous for apoB truncations is approximately 30% of normal. In a 49-member D-kindred (FHBL phenotype defined as apoB < 40 mg/dl), no apoB truncations were detectable either by immunoblotting of plasma or by sequencing of relevant stretches of the apoB gene. Herein we report on the kinetic parameters of apoB-100-containing lipoproteins in four affected members of the D-kindred, and compare their kinetic values to 14 normal subjects, and 8 previously reported FHBL subjects heterozygous for various truncated forms of apoB. After an 8-h primed intravenous infusion of [13C]-leucine, enrichments of apoB-100 were assessed by gas chromatography-mass spectrometry and kinetic parameters were calculated by multicompartmental modeling. The affected members of the D-kindred had similar very low, intermediate, and low density lipoprotein (VLDL, IDL, and LDL) PRs as normal controls, but their fractional catabolic rates (FCR) for VLDL and LDL were approximately 2 and 3 times higher, respectively, than those of normals. By contrast in apoB truncation subjects, apoB-100 PRs were uniformly reduced, while apoB-100 FCRs were similar to normals. Thus, diverse physiologic mechanisms are responsible for the low apoB levels in these two different, genetically determined forms of FHBL.

The effects of consecutive exposures to dietary thiouracil (TU) in juvenile and adult Single Comb White Leghorn chickens on plasma thyroxine (T4) concentrations, egg production (EP), egg weight (EW), concentrations eggshell quality were determined. Thiouracil was provided in the feed at levels of 0, 0.1, or 0.2% (PTRT) from 0 to 6 wk of age and at levels of 0 or 0.1% (TRT) from 32 to 38 wk of age. Body weight gain was simulated but T4, EW, EP, and eggshell quality were generally reduced by 0.1% TU TRT. However, TU PTRT alleviated a latent depressing effect of TU TRT on BW after 38 wk of age. Thiouracil PTRT, particularly at the 0.2% level, induced significant decreases in EW but increased EP between 32 and 50 wk. The effects of early thyroid suppression in juveniles with TU PTRT on the subsequent reproduction of adults were primarily in response to a delay in the onset of sexual maturity, and not directly to prolonged responses in T4 or BW that extended into lay.

Two trials utilizing two corn diets and four wheat diets were conducted. In Trial 2, all chicks were crop-infused at 9 d of age with Eimeria acervulina. In both trials, a broth culture of Clostridium perfringens was mixed with the diets for 3 consecutive d. Necrotic enteritis lesion scores were lowest in chickens consuming the corn diet with no C. perfringens and highest in chickens fed the wheat diets with C. perfringens. Chickens consuming a wheat diet with no added complex carbohydrates or added fiber exhibited the highest lesion score. Chickens on wheat diets with 4% new, ground, pine shavings had intestinal lesion scores intermediate to those of chickens that consumed the wheat or corn diets. Chickens consuming corn diets yielded the lowest lesion scores. Chickens provided diets containing either guar gum or pectin were not fully consumed and thus probably reduced the number of challenge organisms ingested.

The effects of dietary lard on serum glucose (GLU) and lipids were determined in Athens-Canadian randombred broiler chickens. Birds were provided either 0, 3, or 7% added lard in nonisocaloric starter diets through 10 d of age (S1), followed by either 3 or 7% added dietary lard through 21 d of age (S2). A common grower diet was fed to all birds after 21 d. Body and organ weights, feed conversion, and concentrations of various blood constituents, including serum GLU and lipids, were determined weekly from 14 to 42 d of age. Constant levels of added fat in both S1 and S2 diets generally led to higher BW in males at 42 d. Relative testes weight at 14 d was higher in males fed 3% than in those fed 7% S2 diets, whereas 7% added lard in S2 diets preceded by no added fat in S1 diets resulted in higher relative spleen weights in males at 42 d. Serum GLU concentrations were highest in males that received 3% lard rather than no added lard in the S1 diet. Serum low density lipoprotein cholesterol (LDLC) concentrations at 14 d were highest in females fed constant levels of lard at either 3 or 7% in both starter periods. It was concluded that added lard fed to randombred chickens at various times and levels in starter diets elicited responses in organ weight and serum LDLC and GLU concentrations that varied with the sex and age of the bird and were not consistently related to BW.

The purpose of the present study was to investigate the effects of elevated corticosterone (CORT) on circulating lipoprotein cholesterol during a 1-wk period. For this study, 15 commercial broilers were randomly assigned to one of three treatment groups. Group 1 served as the control (CON) and received no treatment, whereas Groups 2 and 3 received subcutaneous mini-osmotic pumps containing either physiological saline (PS) or adrenocorticotropin (ACTH), respectively. The ACTH was delivered at a rate of 8 IU/kg of BW/d. Blood samples were taken at Time 0 (before implants) and on Days 2, 4, and 7 postimplantation. Continuous infusion of ACTH increased plasma glucose, cholesterol, triglycerides, very low density lipoprotein cholesterol, low density lipoprotein cholesterol, high density lipoprotein cholesterol, and CORT during the postimplantation period. The group treated with ACTH also exhibited a decrease in BW during the last 2 sampling d. There were no differences in any of the serum constituents measured between CON and PS birds, which suggest that CON birds can serve as useful controls. These data suggest that birds given a continuous infusion of ACTH at 8 IU/kg of BW/d can experience changes in plasma lipoprotein cholesterol concentrations along with changes in other blood parameters and may serve as a useful model in accelerated lipoprotein production.

We describe a new truncation of apolipoprotein (apo) B in a white kindred with familial hypobetalipoproteinemia (FHBL). Apo B-43.7, found in a daughter and her father, was due to a C → T change in base position 6162 of the apo B gene converting the arginine (residue 1986) codon CGA to a stop codon TGA. Both subjects were heterozygotes, and both apo B-43.7- and apo B-100-containing particles were present in plasma. On density gradient ultracentrifugation (DGUC), approximately 30% to 40% of apo B-43.7 floated with very—low-density lipoprotein (VLDL)/intermediate-density lipoprotein (IDL)-density particles and 60% to 70% floated with high-density lipoprotein (HDL)-density particles. To assess the metabolism of apo B, 13 C-leucine was infused and its rates of appearance in and disappearance from apo B-43.7- and apo B-100-containing particles were quantified by multicompartmental kinetic analysis. Apo B-100 entered plasma via VLDL with a production rate of 30 mg · kg −1 · d −1 . Fractional catabolic rates (FCRs) for apo B-100 VLDL, IDL, and low-density lipoprotein (LDL) were 20.0, 16.0, and 0.46 pools · d −1 , respectively. The production rate of apo B-43.7 was 9.6 mg · kg −1 · d −1 , and FCRs for apo B-43.7 VLDL- and HDL-like particles were 12.0 and 1.8 pools · d −1 , respectively. Approximately 30% of apo B-43.7 in HDL-density particles was derived from VLDL apo B-43.7, and about 70% appeared to enter the plasma as HDLs. The relatively low production rate of apo B-43.7 is compatible with previous reports that apo B truncations are produced at lower rates than their apo B-100 counterparts.

Mediation of nutrition and environmental stressors through hormonal and physiological responses alters growth performance and lipid metabolism in nonruminants, resulting in substantial impacts on carcass lipid quality. Understanding and managing the factors that control carcass fat quality is a challenge for the swine industry yet provides opportunities to improve final carcass quality and profitability of pork production. Three major contributors to lipid quality in swine are regulation of de novo lipogenesis, dietary lipid composition, and environmental stressors. This chapter will evaluate these contributors and their effects on lipid deposition and quality, as well as nutritional and managerial interventions.

The effects of thyroid suppression induced during the rearing period by providing various dietary thiouracil (TU) regimens on plasma thyroxine (T4) concentrations, growth, and subsequent egg production (EP) and eggshell quality were determined in Single Comb White Leghorn chickens. Thiouracil was provided in the feed at levels of 0, .1, and .2% from 0 to 6 wk of age in Experiment 1, and at levels of 0, .05, and .1% from 6 to 16 wk of age in Experiment 2. In both experiments, T4 concentrations were reduced during TU treatment. However, T4 later became elevated at 12 and 20 wk in both dosage level groups in Experiment 1. Additionally, BW and egg weights were suppressed by both TU treatments, and EP was reduced up to Week 23 in the .1% TU-treated birds and through Week 25 in the .2% TU-treated birds. No effects on EP were noted in Experiment 2, but feed consumption (FC) was reduced during Week 6 in birds fed .05% TU and during Weeks 6, 10, and 19 in birds fed .1% TU. Both liver and thyroid weights were increased in .1% TU-treated birds relative to controls at Week 16. Eggshell quality was affected only in Experiment 2, in which birds given .05% TU had a higher relative conductance, or maximum rate of water loss, at Week 38 than 0 and .1% TU dosage levels, and .1% TU-treated birds had a higher breaking strength than 0 and .05% TU-treated birds at Week 22. Without associated effects on eggshell quality, EP may be altered through prior changes in FC, BW, and T4 concentration by using TU at a dosage appropriate for the type and age of bird.

In two experiments broiler chicks were fed nonisocaloric diets with either 0, 3, or 7% added lard. Megacaloric percentages of all major nutrients were the same in all diets. In Experiment 1 (broiler chicks 0 to 5 d of age), added dietary lard did not affect body, heart, spleen, or pancreas weight. Liver weight was suppressed by the inclusion of lard in the diet, yet liver composition changed, becoming higher in protein and lower in fat. Yolk sac weight decreased during the first 5 d posthatch, with the decrease being most pronounced by 3 d of age. There were no differences in feed consumption due to treatment in Experiment 1. In Experiment 2 (broiler chicks 6 to 11 d of age), added dietary fat resulted in differences in liver, body, and fecal excreta composition. Chicks given 7% added lard had lower liver fat throughout the trial than chicks fed no added lard. Additionally, these chicks had a higher body protein content at 6 and 7 d of age. However, body fat only increased in chicks fed 7% added lard by 11 d of age. Furthermore, chicks receiving 7% added lard had elevated fecal fat at Day 6, but did not consume more feed than chicks receiving 0 or 3% added lard. Additionally, chicks fed lard had lower liver weights than those fed 0% added lard.

Preliminary studies were performed to develop a method for using real-time, B-mode ultrasonography (US) to directly image the internal morphology of the chicken egg and developing embryo. Different soft tissue interfaces will reflect US waves differentially. These reflected waves, or echoes are then converted into a two-dimensional image of internal morphology. A major limitation of diagnostic US is its inability to penetrate through gas or hard tissue (bone, shell) interfaces. Methodology development to overcome the acoustic obstacle presented by the eggshell and air cell constituted the initial part of the preliminary study. An acoustical window was achieved by creating a 2-cm fenestration through the large end of the eggshell, then filling the air cell with sterile saline. Morphological features of the yolk and embryo were recorded at 0, 2, 6, 9, 14, and 17 days of incubation. The second part of the preliminary study explores whether the acoustic window, once created, could then be closed, and if closed, whether egg viability could be maintained. A second concurrent trial was conducted with 32 eggs that were fenestrated, imaged, recorded, reclosed, and incubated. Two methods of closure were attempted: one using dialysis membrane and tape; the other using an eggshell allograft. Hatchability was partially retained with both window closure methods.

Various physical and chemical properties of a mixture of pine shavings and sawdust (PS), kenaf core (KC), and whole chopped kenaf (WK) were determined in two successive broiler trials. In Trial 1, each material was placed into pens at a depth of approximately 11 cm. Litter from four replicate pens of each material was analyzed periodically for pH, N, and moisture. Body weight, feed consumption, breast blisters, manure burns, and litter caking scores were determined at the end of each trial. Prior to Trial 2, all litter was turned and WK and KC were topdressed to attain similar litter weights in pens among treatments. In both trials, litter N and moisture increased at each sampling time. The WK and KC had higher moisture and N content throughout both trials. Litter pH increased throughout Trial 1 and reached a maximum value of 8.75 at the end of the trial. In Trial 2, pH values were inconsistent but values over 8.0 were maintained. Litter type had no effect on body weight, feed conversion, breast blister, and manure burn scores in either trial. The WK and KC exhibited significantly more caking than PS.

Dried corn distillers grains with sol- ubles (DDGS) fed to swine may adversely affect car- cass quality due to the high concentration of unsatu- rated fat. Feeding CLA enhances pork quality when unsaturated fat is contained in the diet. The effects of CLA on growth and pork quality were evaluated in pigs fed DDGS. Diets containing 0, 20, or 40% DDGS were fed to pigs beginning 30 d before slaughter. At 10 d before slaughter, one-half of each DDGS treatment group was fed 0.6% CLA or 1% choice white grease. Carcass data, liver- and backfat-samples were collected at slaughter. Longissimus muscle area, 10th-rib back- fat depth, last rib midline backfat depth, LM color, marbling, firmness and drip loss, and bacon collagen content were not altered by DDGS or CLA. Outer layer backfat iodine values were increased (P ≤ 0.05) with DDGS feeding and were 65.07, 69.75, and 74.25 for 0, 20, and 40% DDGS, respectively. Addition of CLA de- creased (P ≤ 0.05) outer layer backfat iodine values from 71.11 to 68.31. Diets containing DDGS decreased (P ≤ 0.05) percent lean tissue contained in bacon from 48% for controls to 38% for pigs fed 40%. Abundance of fatty acid synthase, carnitine palmitoyl transferase Ia, acetyl-CoA-carboxylase, stearoyl-CoA desaturase, and glycerol-3-phosphate dehydrogenase mRNA in adi- pose or liver were not different (P > 0.05) for pigs fed DDGS. Feeding CLA decreased (P ≤ 0.05) the ∆ 9 de- saturase index in adipose tissue. The data indicate that decreased carcass firmness with DDGS feeding is not reflected by changes in lipogenic gene expression. Feed- ing 20% or more DDGS to finishing swine decreases bacon leanness, but inclusion of 0.6% CLA in the fin- ishing diet can partially reverse these effects.

Managing stressors is essential for optimizing pig growth performance. To determine the effects of temperature and space allocation on growth performance and carcass characteristics, pigs were housed within their thermoneutral zone, at 23.9 degrees C, or above their thermoneutral zone, at 32.2 degrees C, and were provided either 0.66 or 0.93 m(2)/pig for the final 35 d of the grow-finish period. Individual BW were recorded on d 1, 10, 20, and 30. At slaughter, carcass measurements and samples of backfat and belly fat were collected. Final BW was decreased (P < or = 0.05) from 113 to 103 kg for pigs housed at 32.2 degrees C. The ADG was reduced (P < 0.05) for pigs housed at 32.2 degrees C (0.89 vs. 0.54 kg/d), as was G:F (0.28 vs. 0.24). Housing at 0.66 m(2)/pig resulted in pigs that were lighter (P < or = 0.05), at 106 compared with 110 kg, as a result of decreased (P < or = 0.05) ADG (0.78 to 0.65 kg/d) and decreased (P < or = 0.05) G:F (0.275 to 0.255) compared with pigs housed at 0.93 m(2)/pig. Pigs housed at a greater spatial allocation had elevated (P < or = 0.05) ADFI. The interaction of housing at 32.2 degrees C and decreasing spatial allocation increased (P < or = 0.05) the adipose iodine value from 66.8 to 70.4, decreased (P < or = 0.05) the saturated:unsaturated fatty acids ratio from 0.59 to 0.56, and increased (P < or = 0.05) the n-6:n-3 from 23.56 to 25.27. Decreased spatial allocation resulted in decreased (P < or = 0.05) belly weights. Although increased temperature did not affect belly weight, the 32.2 degrees C pigs had decreased (P < or = 0.05) raw and cooked slice weights, increased (P < or = 0.05) percentage lean of bacon, increased (P < or = 0.05) lean:fat ratio of bacon slices, increased (P < or = 0.05) raw slice scores, and increased (P < or = 0.05) quantity of collagen in belly fat. Some of these changes may have resulted from changes in lipid metabolism. Increasing spatial allocation in the 32.2 degrees C pigs decreased fatty acid synthase (P = 0.03) and stearoyl-CoA desaturase- 1 (P = 0.08) mRNA expression in adipose tissue. The results from this study demonstrated decreased growth, carcass lipid quality, and bacon quality in pigs housed at temperatures above the thermoneutral zone; however, increasing the spatial allocation for housing may be a means to ameliorate the negative effects of temperature stress.

Two experiments were conducted to determine if l -carnitine injected in ovo affected hatchability. Eggs of experiment 1 were injected with sterilized saline (0.85%) or l -carnitine (0.25, 0.50, 1.00, or 2.00 μmol dissolved in saline). An additional group of eggs served as noninjected controls. Hatchabilities were unaffected by treatment (94% for noninjected controls; 94% for saline injected eggs; and 87, 87, 88, and 88% for eggs injected with 0.25, 0.50, 1.00, or 2.00 μmol of l -carnitine, respectively; SEM = 1). Yolk sac weights retrieved from hatchings that were subjected to 0, 0.25, or 0.50 μmol of l -carnitine as embryos through in ovo injection were 3.9, 3.8, and 3.6 g, respectively (SEM = 0.1, P = 0.71). Eggs used in experiment 2 were injected with a wider dosimetry of l -carnitine. Fertile eggs were injected with sterilized saline (0.85%) or l -carnitine (0.05, 0.5, 5, or 10 μmol dissolved in saline). An additional group of eggs served as noninjected controls. Chick BW and % hatch were unaffected by treatment (76% for noninjected controls; 74% for saline injected eggs; and 77, 77, 68, and 76% for eggs injected with 0.05, 0.5, 5, or 10 μmol of l -carnitine, respectively; SEM = 3). In ovo injection of l -carnitine into fertile chicken eggs at 17 or 18 d of incubation did not affect hatchability, yolk sac weight, or BW.

A previous study conducted in our laboratory showed that feeding 500 ppm of dietary L-carnitine to young and aging White Leghorns for 5 wk improved sperm concentration and reduced sperm lipid peroxidation during the last half of supplementation. The current study examined the effect of feeding dosimetric as well as lower levels of L-carnitine for longer durations on semen traits of White Leghorns. In experiments 1 and 2, White Leghorns consumed diets supplemented with 0, 125, 250, or 500 mg of L-carnitine/kg of feed. For experiment 1, an 8-wk trial was conducted with 48 White Leghorns from 46 to 54 wk of age. For experiment 2, a 17-wk trial was conducted with 96 White Leghorn roosters from 46 to 63 wk of age. For experiment 3, 84 roosters were provided for ad libitum consumption a diet formulated to contain 0 or 125 ppm of L-carnitine beginning at hatch until 37 wk of age. Long-term consumption of 125 ppm of L-carnitine beginning at hatch was the only dietary treatment that sustained a persistent increase in sperm concentration. These results suggest that L-carnitine's antioxidant influence on sperm production begins before the onset of sexual maturity.

Skeletal muscle atrophy results from an imbalance in protein degradation and protein synthesis and occurs in response to injury, various disease states, disuse, and normal aging. Current treatments for this debilitating condition are inadequate. More information about mechanisms involved in the onset and progression of muscle atrophy is necessary for development of more effective therapies. Here we show that expression of the mouse ether-a-go-go related gene (Merg1a) K+ channel is up-regulated in skeletal muscle of mice experiencing atrophy as a result of both malignant tumor expression and disuse. Further, ectopic expression of Merg1a in vivo induces atrophy in healthy wt-bearing mice, while expression of a dysfunctional Merg1a mutant suppresses atrophy in hindlimb-suspended mice. Treatment of hindlimb-suspended mice with astemizole, a known Merg1a channel blocker, inhibits atrophy in these animals. Importantly, in vivo expression of Merg1a in mouse skeletal muscle activates the ubiquitin proteasome pathway that is responsible for the majority of protein degradation that causes muscle atrophy, yet expression of a dysfunctional Merg1a mutant decreases levels of ubiquitin-proteasome proteolysis. Thus, expression of Merg1a likely initiates atrophy by activating ubiquitin-proteasome proteolysis. This gene and its product are potential targets for prevention and treatment of muscle atrophy.

A study was conducted to determine AMEn, TMEn, apparent amino acid digestibility (AAAD), and true amino acid digestibility (TAAD) of spray-dried egg (SDE), plasma protein (PP), and soybean meal (SBM). AMEn and TMEn values for ducks fed SDE were higher (P < or = 0.001) than for ducks fed PP, which were higher than SBM. The AMEn values were 5.048, 3.230, and 2.605 kcal/g for SDE, PP, and SBM, respectively, with TMEn values of 5.373, 3.555, and 2.930 kcal/g, respectively. Spray-dried egg, PP, and SBM were similar in apparent digestibility of the indispensable amino acids except for methionine, histidine, and valine. Apparent methionine digestibility in SDE (95.5%) was higher (P < or = 0.01) than PP (88.3%) or SBM (91.3%). Apparent digestibilities of dispensable amino acids were similar for SDE, PP, and SBM except proline and alanine. Apparent alanine digestibility in SDE (89.9%) was higher (P < or = 0.05) than in SBM (85.7%). True digestibilities of indispensable amino acids were similar in SDE, PP, and SBM except for methionine, histidine, and valine. True methionine digestibility was higher (P < or = 0.05) for SDE (97.0%) than for PP (89.8%) or SBM (92.7%), with PP and SBM being similar. True histidine and valine digestibilities were significantly lower for SDE (P < or = 0.05) than for PP or SBM. True digestibilities of the dispensable amino acids were also similar in SDE, PP, and SBM except for proline and alanine. This study demonstrates that the energy value of SDE is greater than that of PP or SBM.

Objective—To compare kinetics of the metabolism of very-low-density lipoprotein (VLDL) apolipoprotein B (apoB) before and after thyroidectomy in mares. Animals—5 healthy adult mares. Procedure—Thyroidectomy was performed in euthyroid mares. Kinetics of VLDL apoB metabolism were measured before and after thyroidectomy by use of a bolus IV injection of 5,5,5-2H3 (98%) leucine (5 mg/kg) and subsequent isolation of labeled amino acid from plasma and VLDL. Labeled leucine was quantified by use of gas chromatography-mass spectrometry. Production rate (PR), delay time, and fractional catabolic rate (FCR) were calculated for the 2 forms of equine VLDL, apoB-48 VLDL, and apoB-100 VLDL. Plasma lipid concentrations were measured, and VLDL composition was determined. Results—Physical appearance of horses was not altered by thyroidectomy. Significantly lower mean blood concentrations of thyroid hormones and nonesterified fatty acids were detected following thyroidectomy. Mean percentage of free cholesterol in VLDL was significantly higher after thyroidectomy. Mean plasma VLDL concentration or kinetics of apoB-48 or apoB-100 were not significantly altered by thyroidectomy. Mean ± SEM PR was significantly lower (8.70 ± 1.61 mg/kg/d) and mean delay time significantly longer (1.58 ± 0.12 hours) for apoB-48 VLDL in euthyroid mares, compared with values for thyroidectomized mares (16.15 ± 2.24 mg/kg/d and 0.93 ± 0.10 hours, respectively). Conclusions and Clinical Relevance—Hypothyroidism did not significantly alter plasma VLDL concentrations or kinetics of VLDL apoB metabolism. Metabolism of apoB-48 VLDL differed significantly from that of apoB-100 VLDL in euthyroid mares. (Am J Vet Res 2003;64:1052–1058)

The purpose of this study was to investigate the effects of duck breeder age on circulating very low density lipoprotein (VLDL) and low-density lipoprotein (LDL) levels in embryonic (day 25 of incubation) and newly hatched ducklings (hatch and 1, 2, 3, and 5 days after hatch). In this study, embryos and ducklings from one breeder flock were monitored at breeder ages 24 weeks (young breeders), 31 weeks (mature breeders and near peak egg production), and 47 weeks (after peak egg production). Embryos and newly hatched ducklings from young breeders (24 weeks of age) displayed lower levels of VLDL and LDL. The composition of VLDL was affected by breeder age such that embryos and ducklings from young breeders had less cholesterol ester/protein and triglyceride/protein ratios. Even though the overall levels were suppressed in embryos and newly hatched ducklings from 24-week-old breeders, the overall percentage of triglyceride within VLDL and LDL particles was higher. These data would suggest that breeder age affects concentration and composition of both VLDL and LDL in embryos and newly hatched ducklings.

Objective—To measure and compare the concentration and composition of very low-density lipoprotein (VLDL) in plasma and selected lipids in serum of horses fed mixed grass hay ad libitum or denied feed for 36 hours. Animals—4 healthy adult mares. Procedure—Mares were either fed mixed grass hay ad libitum or denied feed for 36 hours beginning at 8:00 AM. Blood samples were collected every 2 hours during the study period and analyzed for nonesterified fatty acid (NEFA), triglyceride (TG), VLDL, and glucose concentrations and composition of VLDL. Results—Withholding feed significantly increased mean serum concentrations of NEFA. By 36 hours, a 16-fold increase in mean serum NEFA concentration and 2-fold increase in mean plasma VLDL concentration, compared with baseline values, were detected. Mean plasma TG concentrations significantly increased with time in feed-deprived horses. Significantly lower overall mean plasma glucose concentrations were detected in feed-deprived horses. Mean percentage of protein in VLDL was significantly lower in feed-deprived horses. Plasma VLDL concentrations varied widely among horses in response to withholding feed. Plasma TG and VLDL concentrations remained unaltered in 2 horses. Conclusions and Clinical Relevance—Withholding feed significantly increases blood lipid concentrations in horses, but individual horses respond differently. Serum NEFA concentrations were increased in all 4 horses denied feed, indicating mobilization of tissue triglyceride stores. Variation in plasma VLDL concentration in response to withholding feed suggests that its metabolism is strongly influenced by other, as yet undetermined, factors in horses. Differences in the plasma VLDL concentrations among horses in response to withholding feed may be used as an indication of susceptibility to the hyperlipemic syndrome of Equidae. (Am J Vet Res 2002;63:1018–1021)