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We studied the chemical composition and the in vivo AMEn content and apparent (AID) and standardized (SID) ileal digestibility of CP and amino acids (AA) of 27 samples of soybean meals (SBM) from Argentina (ARG), Brazil (BRA), and USA, collected in Spain. On 88% DM basis, the BRA meals had more CP (46.9 vs. 46.0 and 45.9%; P < 0.05) and less sucrose (5.21 vs. 6.28 and 6.47%; P < 0.001) and stachyose (4.20 vs. 4.66 and 4.78%; P < 0.05) than the USA and ARG meals. Urease activity, protein dispersibility index, KOH protein solubility, and trypsin inhibitor activity values, were higher for the USA meals than for the South American meals (P < 0.05). In the in vivo trial, broilers received a common crumble diet from 0 to 16 d of age and then, their respective experimental diets (53% of a N-free diet and 47% of each of the 27 SBM tested) in mash form, for 5 d. The AMEn (2,334 vs. 2,282 and 2,277 kcal/kg; P = 0.062) and the AID (87.3 vs. 86.7 and 86.4%; P = 0.054) and SID (91.9 vs. 91.2 and 90.8%; P < 0.05) of the protein, were greater for the USA meals than for the ARG and BRA meals. In fact, the SID of Lys (93.5 vs. 93.0 and 92.1%; P < 0.001) and of the sum of Lys, Met, Thr, Trp, and Cys (91.4 vs. 91.0 and 90.2%; P < 0.05) were greater for the USA meals than for the ARG and BRA meals. In summary, the chemical composition, protein quality indicators, AMEn content, and ileal digestibility of the CP and the AA of the SBM, varied with the country of origin of the soybeans. In order to increase the accuracy of the feed formulation process, the composition and nutrient content of commercial batches of SBM, by country of origin should be controlled and periodically updated., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

The main objective of this study was to present data on the current situation and future trends of pig meat production in the European Union-27 (EU). Pig production has played an important social and economic role for centuries in many states of the EU. In 2022, pig meat production in the EU reached 23 M tons, which represented 21% of total production worldwide. The two key reasons that justify such amount of pork produced, are the acceptance and high consumption of the meat by the local population and the high quality of the meat produced which facilitated pork export. However, current data show a reduction in pork production for the last three years, as a consequence of a series of events that include i) problems with the chain of ingredients supply, ii) uncontrolled increase in African Swine Fever (ASF) outbreaks, iii) fast recovery of pig production in China, iv) increasing concerns by the rural population on the high cost to meet future requirements of the EU legislation on farm management, environmental sustainability and animal welfare, v) increased cost of all inputs involved in pig production and vi) limited interest of the new farmer generation to work on the pig sector. Consequently, pork production is expected to decrease in the EU for the next years, although sales will be maintained at a relative high level because pork is the meat preferred by local consumers in most EU countries. In order to maintain the favourable position of the pork industry in the near future, strategies to implement include: i) maintain the quality of the meat destinated to export markets, ii) improve the control of outbreaks of ASF and other swine diseases, iii) implementation of technological innovations to improve working conditions making more attractive to work in the pork sector of the food chain to the new generation of farmers and workers.

The hypothesis of this experiment was that a liquid rich in hydroxytyrosol (HT) obtained from "alperujo", an olive oil by-product, could replace part of the added vitamin E (VE) as an antioxidant in poultry diets. There were five diets that differed exclusively in the substitution of supplemental VE (0 to 40 mg/kg, with differences of 10 mg/kg) by HT (30 to 0 mg/kg, with differences of 7.5 mg/kg). The basal diet was based on corn and soybean meal and provided 10 mg VE/kg. From 0 to 39 d of age, the growth performance of the birds was not affected by diet. The birds were slaughtered at 39 d of age to evaluate the quality of the breast, and malonaldehyde concentration, pH, color, and drip loss were measured. In terms of meat lipid oxidation, the combination of 22.5 mg HT/kg and 10 mg of added VE/kg equalized to a diet supplemented with 40 mg VE/kg. Meat color improved in broilers fed 7.5 mg HT/kg and 30 mg VE/kg. It is concluded that once the nutritional requirements of the birds in VE are satisfied, the dietary supplementation with the olive oil by-product rich in HT can be used as a strategy to spare VE in broiler diets.

The influence of the Ca and nutrient content of the diet fed from 16 to 19 wk of age, on egg production, egg quality, and tibiae mineralization, was studied in brown egg-laying hens from 16 to 63 wk of age. The experimental design was completely randomized with 4 prelay diets organized as a 2 × 2 factorial with 2 levels of Ca (2.5 vs. 3.8%) and 2 standardized ileal digestible Lys (g/kg) to AMEn (Mcal/kg) ratios (DLys:ME; 2.84 vs. 3.13) as main effects. From 20 to 63 wk of age, all hens received a common diet with 2.75 Mcal AMEn/kg, 0.75% DLys, and 3.8% Ca. Each treatment was replicated 18 times and the experimental unit was a cage with 10 hens. Hen production and egg quality traits were measured by period (4 wk), feeding phase (prelay and lay), and cumulatively (16-63 wk of age) and tibiae mineralization was measured at 63 wk of age. During the prelay phase, an increase in Ca delayed egg production (P = 0.065), reduced feed intake (P < 0.05), and increased BW gain (P < 0.01) and percentage of shell of the egg (P < 0.05). An increase in the DLys:ME ratio increased feed intake (P < 0.01) and reduced egg size (P < 0.01). Nutrient content of the prelay diets did not affect hen production during the lay phase, except egg weight that increased (P < 0.05) in hens previously fed the low DLys:ME ratio. Eggshell quality (weight, percentage, strength, and thickness) in this phase was better (P < 0.05) in hens previously fed 3.8% Ca. Cumulatively (16-63 wk of age), hens fed the high Ca prelay diets had better shell quality but tibiae mineralization was not affected. In conclusion, an increase in Ca content of the prelay diet from 2.5 to 3.8% improved shell quality for the entire egg cycle without showing any negative effect on hen production., Competing Interests: DISCLOSURES The authors confirm that there are no conflicts of interest in this research., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

The influence of the energy and the standardized ileal digestible lysine (DLys) content of the diet on egg production and egg quality, was studied in brown-egg laying hens from 18 to 41 wk of age. The experimental design was completely randomized with 10 treatments organized as a 2 × 5 factorial with 2 energy concentrations (2,750 and 2,800 kcal AMEn/kg) and 5 levels of DLys (values varied from 0.66 to 0.78% and 0.67 to 0.79%, for the low and high energy diets, respectively). Each treatment was replicated 10 times (10 hens per replicate). The data were analyzed using the MIXED procedure of SAS with energy concentration and DLys content of the diets as main effects. In addition, the effects of the DLys on the variables studied were partitioned into its lineal and quadratic components. From 18 to 21 wk of age (pre-peak phase), diet composition had limited effects on egg production. From 22 to 41 wk of age (peak phase), however, an increase of 50 kcal AMEn/kg diet increased egg weight (P < 0.05) and tended to improve energy intake (P = 0.083) and feed conversion ratio (P = 0.074). An increase in DLys improved linearly (P < 0.001) egg production, egg weight, egg mass, feed conversion, and energy conversion ratio, and tended to increase BW gain (P = 0.074). Diet composition did not any affect egg quality trait except shell strength that increased linearly (P < 0.05) with increases in the DLys. Cumulatively (18-41 wk of age), egg weight increased (P < 0.05) as the energy and the DLys content of the diet increased. In summary, an increase in energy and DLys content of the diet had limited effects on egg production during the prepeak phase but improved egg production, feed conversion ratio, and BW gain during the peak phase. The data indicate that hens require at least 839 mg DLys/d to maximize egg production in the peak production phase., Competing Interests: DISCLOSURES The authors confirm that there are not conflicts of interest in this research., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

The influence of infrared beak trimming at hatch (IRBT) and the inclusion of oat hulls (OH) in the diet on growth performance, feed preference, exploratory pecking behavior, and gastrointestinal tract (GIT) development, was studied in brown-egg pullets from 0 to 15 wk of age. The experimental design was completely randomized with 4 treatments arranged as a 2 × 2 factorial with IRBT (sham vs. treated) and OH inclusion (0 vs. 3%) as main effects. Each treatment was replicated 20 times and the experimental unit was a cage with 10 pullets. Feed intake (FI), BW gain, feed conversion ratio (FCR), energy intake (EI, kcal AMEn/d), and energy conversion ratio (ECR, kcal AMEn/g of BW gain) were determined by feeding period (0 to 6, 7 to 10, and 11 to 15 wk of age) and cumulatively. Particle size preference was measured at 7 wk and exploratory pecking behavior of the pullets and at 8 to 14 wk of age. From 0 to 6 wk of age, beak trimming decreased FI (P < 0.01) and increased pullet mortality (P < 0.001) but did not affect BW gain. From 0 to 15 wk of age, OH inclusion improved BW uniformity (P = 0.090) but impaired FCR (P < 0.05) without showing any effect on BW gain or ECR. Preference for coarse particles was greater for the sham than for the treated pullets. Beak trimming and OH feeding reduced (P < 0.05) the exploratory pecking behavior of the pullets from 8 to 12 wk of age but not thereafter. Oat hulls increased the relative weights of the full gizzard and intestines at all ages (P < 0.05). In summary, beak trimming did not affect pullet performance at 15 wk of age or GIT development at any age. Oat hulls improved GIT development at all ages but did not affect BW or ECR. Both beak treatment and OH inclusion affected particle size preference and reduced the exploratory pecking behavior of the birds., Competing Interests: DISCLOSURES The authors confirm that there are not conflicts of interest in this research., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

The influence of nutrient density and standardized ileal digestible lys (DLys) content of the diet on egg production and egg quality traits, was studied in brown-egg laying hens from 19 to 59 wk of age. The experimental design was completely randomized with eight treatments arranged as a 2×4 factorial with two AMEn concentrations (2,680 and 2,780 kcal/kg) and four levels of DLys (0.68, 0.72, 0.76, and 0.80%). Each treatment was replicated nine times and the experimental unit was a cage with nine hens. Hen production, egg components (proportion of albumen, yolk, and shell), egg quality traits (Haugh units, egg shell strength, and incidence of broken, dirty, and shell-less eggs) were measured by period (28 d) and cumulatively. Data were analyzed as a completely randomized design with energy concentration, level of DLys, and their interactions as main effects. In addition, the effects of the level of DLys on the variables studied, were partitioned into its linear and quadratic components. No interactions between AMEn and DLys content of the diet were detected for any of the traits studied and therefore, only main effects are presented. An increase in the AMEn concentration of the diet from 2,680 to 2,780 kcal/kg increased energy intake (P < 0.05) and egg weight (P < 0.001) and improved feed conversion ratio (P < 0.05). An Increase in DLys from 0.68 to 0.80% did not affect the number of eggs produced but increased linearly egg weight (P < 0.01) and egg mass production (P < 0.05). Diet did not affect egg quality. In conclusion, an increase in the AMEn content of the diet from 2,680 to 2,780 kcal/kg increased egg weight and improved feed efficiency. Laying hens require no more than 744 mg DLys/d (corresponding to 0.68% DLys) to optimize egg production. However, when the objective is to maximize egg weight, hens should consume at least 843 mg DLys/d (corresponding to 0.76% D Lys)., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

An experiment was conducted to test the hypothesis that inclusion of hybrid rye in diets containing corn and soybean meal (SBM) without or with microbial phytase improves the apparent total tract digestibility (ATTD) and the standardized total tract digestibility (STTD) of P because of the intrinsic phytase activity in hybrid rye. Forty-eight growing barrows (initial body weight: 39.5 ± 7.7 kg) were allotted to six diets. A basal diet containing corn and SBM; a rye-based diet; and a diet containing corn, SBM, and rye were formulated. Each diet was formulated without and with microbial phytase (500 units/kg of diet) for a total of six diets. Fecal samples were collected for 4 d following a 5-d adaptation period according to the marker-to-marker procedure. Results indicated that no interactions between diets and concentration of phytase were observed for any of the response criteria measured. The ATTD and STTD of P and the ATTD of Ca differed (P < 0.05) among diets, but regardless of diet, the concentration of P in feces was reduced (P < 0.05) by adding microbial phytase to the diets. As a consequence, microbial phytase increased (P < 0.05) ATTD and STTD of P, and the ATTD of Ca was also increased (P < 0.05) by the use of microbial phytase. Measured values for the ATTD and STTD of P in the diets containing corn, SBM, and hybrid rye without or with phytase were greater (P < 0.05) than values that were predicted based on the ATTD and STTD of P for the corn-SBM and the hybrid rye diet. The observation that STTD predicted from the individual ingredients underestimated the STTD of P in the mixed diet indicates that the intrinsic phytase in hybrid rye resulted in increased digestibility of the P in the corn and SBM included in the corn-SBM-hybrid rye diet. In conclusion, microbial phytase increased the ATTD and STTD of P and the ATTD of Ca regardless of feed ingredients used in diets fed to pigs. In addition, the intrinsic phytase from hybrid rye increased the ATTD and STTD of P in corn and SBM., (© The Author(s) 2020. Published by Oxford University Press on behalf of the American Society of Animal Science. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

We studied the effects of restricting the access to feed on the anticipatory eating behavior, growth performance, and the development of the proximal part of the gastrointestinal tract (GIT) in broilers. The experiment consisted in physical restriction of the access of broilers to feed for 0, 4, 6, or 8 h per day from 7 to 19 D of age. At 10, 13, 16, and 19 D of age, immediately before the start of the feed restriction (FR) period, 2 birds per cage were euthanized to evaluate crop and gizzard development. The experimental design was completely randomized, and the linear (L) and quadratic (Q) effects of fasting length on growth performance and GIT traits were determined. In addition, the effect of broiler age on GIT development was studied. From 7 to 19 D of age, ADFI (L, Q; P ≤ 0.05) and BW gain (L; P ≤ 0.01) decreased as the length of the FR period increased, with most of the differences observed with 6 or more hours of fasting. However, feed conversion ratio was not affected by FR length. The relative weight of the crop (% BW) and its fresh content increased (L; P ≤ 0.001) and the moisture of the digesta (%) decreased (L; P ≤ 0.001) as the FR period increased. The DM content (g) of the crop increased with FR, with most of the differences observed with 6 or more hours of fasting (L, Q; P ≤ 0.001). At 19 D of age, the Lactobacillus spp. count in the crop increased (L; P ≤ 0.05) with increase in the FR period. Fasting did not affect any gizzard trait at any age. In summary, physical restriction of the access to feed for 6 h or more reduced BW gain but did not affect feed conversion ratio in broilers from 7 to 19 D of age. Feed restriction for 4 to 8 h stimulated the anticipatory feeding behavior and crop development in broilers., (Copyright © 2019. Published by Elsevier Inc.)

We studied the influence of pre-hatch egg weight (EW) and the inclusion of oat hulls (OH) in the diet on gastrointestinal tract (GIT) traits and growth performance of pullets reared under stress conditions early in life. There were 14 treatments organized as a 7 × 2 factorial with 7 EW groups (47.0 to 54.0 g differing in 1 g between groups) and 2 inclusion levels of OH in the diet (0 vs. 3%). The pullets were reared under a series of stresses early in life (no access to feed for extended time post-hatching, reduced accessibility to feed and water at arrival to the farm, reduced ambient temperature at night, low light intensity, and hot-blade beak trimming at 18 D of age). Feed intake, BW gain, and FCR were measured by period (0 to 5, 5 to 10, and 10 to 16 wk of age) and cumulatively. Data were analyzed as a completely randomized design with EW and OH inclusion as main effects. In addition, EW effect was partitioned into linear and quadratic components. The stress conditions applied affected similarly the growth and GIT development of the pullets, independent of EW. An increase in EW increased BW at hatch and at 5 wk of age linearly (P < 0.05), but no effects were detected thereafter. Oat hulls inclusion increased ADFI and impaired FCR (P < 0.05) from 0 to 5 wk of age but did not affect energy efficiency at any age. At 5 wk of age, the relative weight (% BW) of the GIT decreased linearly (P < 0.05) with increases in EW and increased with OH inclusion (P < 0.05). Oat hulls inclusion increased the relative weight of the gizzard at all ages (P < 0.01). In conclusion, egg weight did not affect pullet growth from hatch to 16 wk of age. Independent of the initial BW of the pullets, OH inclusion improved gizzard development at all ages without affecting growth performance., (© 2019 Poultry Science Association Inc.)

We studied the effects of beak trimming and sodium-butyrate inclusion in the diet on growth performance and gastrointestinal tract (GIT) traits of brown-egg pullets differing in initial BW. In experiment 1, a total of 6 treatments were organized as a 2 × 3 factorial with 2 BW at hatch (light, 33.9 g and heavy, 37.6 g) and 3 beak trimming protocols [mild (MI-0) or aggressive (AG-0) infrared power setting at hatch and traditional hot blade at 8 D of age (HB-8)] as main effects. Initial BW did not affect growth performance or GIT traits at any age. From hatch to 5 wk of age, HB-8 pullets had lower ADFI (P < 0.01) and ADG (P < 0.05) than MI-0 and AG-0 pullets but no differences were detected after this age. Beak trimming did not affect FCR, BW uniformity, GIT traits, or bacteria count in the excreta at any age. In experiment 2, a total of 12 treatments were organized as a 2 × 3 × 2 factorial, with 2 BW at hatch, 3 beak trimming protocol (as per in experiment 1), and 2 levels of a sodium-butyrate additive (0 vs. 0.3%) as main effects. At 7 D of life, beak treatment reduced pullet growth and AG-0 procedure impaired pullet uniformity (P < 0.001) but the birds recovered completely by day 14 (P < 0.001 for the interaction with time). Cumulatively (0 to 6 wk of age), pullets beak treated at hatch (MI-0 and AG-0) had greater ADFI than HB-8 pullets (P < 0.01). Sodium butyrate tended to improve ADG (P = 0.073) and FCR (P = 0.069) with most of the benefits observed for the first 2 wk of life. In summary, initial BW and beak trimming procedure did not affect final pullet growth in any of the 2 experiments, or GIT traits in experiment 1. Sodium butyrate tended to improve growth and FCR from 0 to 6 wk of age but did not affect BW uniformity., (© 2019 Poultry Science Association Inc.)

The effects of feed form and dietary fiber on the development of the gastrointestinal tract (GIT) and nutrient digestibility were studied in broilers at 8 and 21 d of age. The experiment included 14 treatments arranged as a 2 × 7 factorial with 2 feed forms (mash vs. pellet) and 7 diets that consisted in a low fiber diet and 6 extra diets resulting from the combination of 3 insoluble fiber sources [oat hulls (OH), rice hulls, and sunflower hulls] and 2 levels of inclusion (2.5 and 5.0%). Pelleting decreased the relative weight (% BW) of the full GIT, and empty gizzard (P < 0.001) and the relative length (cm/kg empty BW) of the small intestine and ceca (P < 0.001) and increased full crop (P < 0.001) and liver (P < 0.05) weights. Fiber inclusion increased the empty weight and the fresh digesta content of the gizzard (P < 0.001) but had limited and inconsistent effects on the weight of the full GIT or the length of the small intestine and ceca. Gizzard pH decreased with mash feeding and fiber inclusion (P < 0.001). Pelleting decreased ether extract retention (P < 0.05) but did not affect N retention or AMEn of the diets. Fiber inclusion improved nutrient retention (P < 0.05 to P < 0.001) with more pronounced effects with OH than with sunflower hulls or rice hulls inclusion. The AMEn of the diets increased (P < 0.05) with 2.5% of fiber inclusion but no extra benefits were obtained with a further increase to 5.0%. Starch ileal digestibility increased with mash feeding (P < 0.001) and fiber supplementation (P < 0.05). In summary, pelleting increases full crop weight and gizzard pH and decreased full gizzard weight and starch ileal digestibility. Moderate amounts of insoluble fiber, especially OH, increases gizzard weight, reduces gizzard pH, and improves nutrient digestibility in young broilers., (© 2019 Poultry Science Association Inc.)

The influence of grinding size of the main cereal of the diet on production and egg quality traits was studied in brown hens from 33 to 65 wk of age. The experiment was completely randomized with 6 treatments arranged as a 3 × 2 factorial with 3 main cereals (barley, corn, and wheat) and 2 grinding size of the cereal (6 and 10 mm screen). Each treatment was replicated 11 times (10 hens/replicate). Diets were isonutritive and contained 2,740 kcal/kg AMEn and 16.8% CP. Egg production, ADFI, egg weight, and feed conversion ratio (FCR) were determined by period (4 wk) and for the entire experiment. Egg quality traits (percentage of undergrades, Haugh units, thickness, strength, color of the shell, and proportion of albumen, yolk, and shell) were measured also by period. No interactions between main cereal and grinding size of the main cereal of the diet were observed for any of the traits studied. Feed intake, egg production, and BW gain were not affected by diet or grinding size. Eggs were heavier (P < 0.01) in hens fed barley than in hens fed corn or wheat, probably because of the higher fat content of the barley diets. Also, FCR tended to improve in hens fed barley compared with hens fed corn or wheat (P = 0.07). Diet did not affect any of the egg quality traits studied. In summary, barley and wheat conveniently supplemented with enzymes, can be used in substitution of corn at levels of up to 55% in diets for laying hens, without any adverse effect on egg production or egg quality traits. Moreover, the substitution of corn by a combination of barley and supplemental fat increased egg size. Consequently, the inclusion of one or other cereal in the diet will depend primarily on their relative cost. Within the range studied, screen size (6 vs. 10 mm) of the cereal had limited effects on hen production.

We studied the influence of particle size of the main cereal of the diet on preference behavior by laying hens. Diets formed a 2 × 5 factorial with 2 main cereals (corn vs. barley) and 5 grinding sizes of the cereal (4, 6, 8, 10, and 12 mm screen). Each treatment was replicated 5 times (10 hens each). After a fasting period of 8 h, hens received their respective experimental diets from 06.00 to 14.00 hours. The geometric mean diameter (GMD) and the geometric standard deviation of the residuals in the feeder were determined every 2 hours. In addition, CP, ash, and Ca contents of the feeds were determined at the start and at the end of the experimental period. The experimental design was completely randomized with data analyzed as repeated measures with particle size and cereal as main effects. The GMD of the original feeds increased with increases in screen size and was greater for the barley than for the corn diets. The difference in GMD between the original diets and the residuals measured at 2 h intervals decreased as the experiment progressed (P < 0.001 for the interaction). Crude protein, ash, and Ca concentrated in the coarse fraction of the original diets and of the uneaten feed, an effect more pronounced for the minerals. Independent of the coarseness of the feed sieve, ash and Ca contents were higher in the uneaten feed at 14.00 h than in the original diets. Hens showed a clear preference for coarse particles irrespective of the concentration of CP, ash, or Ca in the different fractions of the diets. Data showed that birds under-consumed Ca during the morning, a period in which the requirements for mineral deposition are low. In summary, hens showed a significant preference for coarser particles, an effect that was more evident when the cereals were ground coarse. Hens, however, did not show any preference for consuming those feed fractions with greater CP, ash, or Ca contents.

The effects of including 3% sunflower hulls (SFH) in the diet on growth performance, nutrient retention (TTAR), and gastrointestinal tract (GIT) traits were studied in chicks from zero to 21 d of age. Four treatments that resulted from the combination of 2 chicken lines (female broilers vs. brown pullets) and 2 levels of SFH (zero vs. 3%) were used. The control diet contained 2,980 kcal AMEn/kg, 1.25% digestible Lys, and 8.7% neutral detergent fiber. The experimental diet included 3% SFH at the expense (wt:wt) of the whole diet. Growth performance, TTAR of nutrients, and the AMEn of the diet were greater (P = 0.097 to P < 0.001) in broilers than in pullets. In absolute terms, all the organs of the GIT were heavier (P < 0.001) and the small intestine and cecum were longer (P < 0.001) in broilers than in pullets. At 21 d of age, however, the relative weight (% BW) of all the organs of the GIT (P < 0.001) and the relative length (cm/kg BW) of the small intestine and cecum (P < 0.01) were greater in pullets. Gizzard pH (P < 0.001), total short chain fatty acids concentration in the cecum (P = 0.098), and villus height (P < 0.001) and crypt depth (P < 0.05) of the ileum mucosa were higher in broilers. The inclusion of SFH increased (P < 0.05) the AMEn content of the diet but did not affect bird performance, moisture content of the excreta, or the concentration and profile of fatty acids in the cecum. Dietary SFH increased gizzard weight and reduced gizzard pH (P < 0.001) at both ages. In conclusion, broilers had better growth performance, nutrient retention, and ileum absorptive capacity than pullets. The inclusion of 3% SFH at the expense of the control diet did not have any negative effect on chick performance and, in fact, increased gizzard weight, reduced gizzard pH, and improved the energy content of the diet., (© 2016 Poultry Science Association Inc.)

The influence of the screen size used to grind the main cereal of the diet on egg production, gastrointestinal tract (GIT) development, and body measurements was studied in hens from 17 to 49 wk of age. Diets formed a 2 × 5 factorial with 2 main cereals (corn vs. barley) and 5 screen sizes of the cereal (4, 6, 8, 10, and 12 mm). Each treatment was replicated 5 times. No interactions between main cereal and screen size were observed for any of the traits studied. Cereal type and screen size did not affect feed intake, egg production, BW gain, or quality traits of the eggs. Eggs tended to be larger (P = 0.092) in hens fed the barley diet than in hens fed the corn diet. Also, feed conversion ratio tended to increase (P = 0.081) when the cereal of the diet was ground with a 4-mm screen as compared with the average of the other diets. At 49 wk of age, the relative weight (% BW) of the GIT and gizzard was greater (P < 0.05) in hens fed barley than in hens fed corn. An increase in the screen size increased linearly the relative weight of the GIT (P = 0.089), gizzard (P < 0.01), and liver (P = 0.056). None of the other GIT traits or body measurements was affected by the main cereal or the screen size. In summary, barley can substitute up to 45% of the corn in diets for laying hens without any adverse effect on egg production. Therefore, the use of one or other cereal will depend on their relative cost. An increase in screen size improved gizzard development but had little effect on hen productivity. Within the range studied, the size of the screen used for grinding the cereal had little effect on hen productivity, although the use of a 4-mm screen might increase feed conversion ratio and gizzard development., (© 2016 Poultry Science Association Inc.)

This research studied the effects of additional fiber in the rearing phase diets on egg production, gastrointestinal tract (GIT) traits, and body measurements of brown egg-laying hens fed diets varying in energy concentration from 17 to 46 wk of age. The experiment was completely randomized with 10 treatments arranged as a 5 × 2 factorial with 5 rearing phase diets and 2 laying phase diets. During the rearing phase, treatments consisted of a control diet based on cereals and soybean meal and 4 additional diets with a combination of 2 fiber sources (cereal straw and sugar beet pulp, SBP) at 2 levels (2 and 4%). During the laying phase, diets differed in energy content (2,650 vs. 2,750 kcal AMEn/kg) but had the same amino acid content per unit of energy. The rearing diet did not affect any production trait except egg production that was lower in birds fed SBP than in birds fed straw (91.6 and 94.1%, respectively; P < 0.05). Laying hens fed the high energy diet had lower feed intake (P < 0.001), better feed conversion (P < 0.01), and greater BW gain (P < 0.05) than hens fed the low energy diet but egg production and egg weight were not affected. At 46 wk of age, none of the GIT traits was affected by previous dietary treatment. At this age, hen BW was positively related with body length (r = 0.500; P < 0.01), tarsus length (r = 0.758; P < 0.001), and body mass index (r = 0.762; P < 0.001) but no effects of type of diet on these traits were detected. In summary, the inclusion of up to 4% of a fiber source in the rearing diets did not affect GIT development of the hens but SBP reduced egg production. An increase in the energy content of the laying phase diet reduced ADFI and improved feed efficiency but did not affect any of the other traits studied., (© 2016 Poultry Science Association Inc.)

The effects of net energy (NE) content of isoproteic diets on growth performance and carcass and meat quality traits were studied in crossbreds from Landrace×Large White females and two Pietrain sire lines (PIC L62 vs. German Pietrain). Feed intake (FI) decreased (Lineal, P<0.001) and feed efficiency improved (Lineal, P<0.001) as the NE content of the diet increased. Crossbreds from PIC L62 had greater (P<0.001) FI and average daily gain (ADG) but were less efficient (P<0.01) than crossbreds from German Pietrain. German Pietrain crossbreds were leaner (P<0.001) and had higher shoulder yield (P<0.01) and less fat at m. Gluteus medius (P<0.001) than carcasses from PIC L62 crossbreds. In summary, an increase in the NE concentration of the diet improved feed efficiency but did not affect ADG. Crossbreeds from PIC L62 sires grew faster and had fatter carcasses than crossbreds from German Pietrain., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

We studied the influence of pen uniformity at weaning (7.5 ± 0.6 kg vs. 7.5 ± 1.2 kg body weight (BW ± SD)) and sex on growth performance during the nursery (7.5 to 27.3 kg BW) and the fattening (27.1 to 130.5 kg BW) phases and carcass quality of barrows and castrated females (CF). During the nursery phase, pigs from the more uniform pens had lower feed efficiency (P = 0.05) than pigs from the less uniform pens. Also, barrows had higher average daily feed intake (ADFI) (P < 0.05) and average daily gain (P < 0.001) and better feed efficiency (P < 0.001) than CF. During the fattening phase, initial pen uniformity did not affect growth performance of the pigs but barrows tended (P = 0.08) to have higher ADFI and worse feed efficiency than CF. Trimmed primal cut yield tended to be higher for the more uniform pigs and better for barrows than for CF (P = 0.09). It is concluded that regrouping of the pigs at weaning according to uniformity of BW did not affect growth performance or carcass quality of the pigs at slaughter. Castrated females might be used as an alternative to barrows for the production of carcasses destined to the dry-cured industry., (© 2015 Japanese Society of Animal Science.)

The effects of feed form and the inclusion of insoluble fiber in the diet on growth performance and water intake were studied in female broilers from 0 to 21 d of age. The experimental design was completely randomized with 14 treatments arranged as a 2 × 7 factorial with 2 feed forms (mash vs. pelleted) and 7 diets that consisted of a control diet low in fiber (1.6% crude fiber) based on broken rice, fermented soybean meal, and fish meal and 6 extra diets that resulted from the inclusion of 3 insoluble fiber sources (oat hulls; OH, rice hulls; RH, and sunflower hulls; SFH) at 2 levels (2.5 vs. 5%). Each treatment was replicated 6 times. Broilers fed pellets had 32% greater ADG and 3% better feed to gain ratio (F:G) than those fed mash (P ≤ 0.001). The inclusion of the fiber sources improved ADG (P ≤ 0.05) and F:G (P ≤ 0.05). Pelleting increased (P ≤ 0.001) water intake from 6 to 8 d, water-to-feed intake ratio from 18 to 20 d, and moisture content of the excreta at 20 d of age. The inclusion of the insoluble fiber sources increased water intake (P ≤ 0.05) from d 18 to 20 but not from d 6 to 8. Increasing the level of fiber inclusion from 2.5 to 5.0% tended to increase (P = 0.086) moisture content in the excreta at d 20. Pelleting and the inclusion of insoluble fiber sources improved ADG and F:G in broilers fed low-fiber diets, and the improvements observed were more pronounced with pellets than with mash. Growth performance of young broilers improves with the addition of moderate amounts of structural insoluble fiber in the diet, regardless of feed form. The inclusion of OH or SFH into low fiber diets was more beneficial for improving broiler performance than the inclusion of RH., (© 2015 Poultry Science Association Inc.)

We investigated the effects of fiber inclusion in the diet on growth performance and digestive traits in pullets from hatching to 17 wk of age. The control diets of the 3 feeding periods (0 to 5 wk, 5 to 10 wk, and 10 to 17 wk) were based on corn and soybean meal and did not include any additional fiber source. The experimental diets included 2 or 4% of cereal straw or sugar beet pulp (SBP) at the expense (wt:wt) of the control diet. From 0 to 5 wk of age, fiber inclusion did not affect pullet performance. From hatch to 17 wk of age, the inclusion of straw had little effect on pullet performance but the inclusion of 4% SBP reduced (ADG) (P < 0.05) and reduced feed conversion ratio (FCR; P < 0.001). Pullets fed straw had greater ADG (P < 0.05) and better energy conversion ratio (P < 0.01) than pullets fed SBP. An increase in fiber from 2 to 4% reduced FCR (P < 0.05). Body weight uniformity was not affected by diet. Fiber inclusion increased the relative weight (% BW) of the gizzard at 5 wk (P = 0.056) and 10 wk (P < 0.01) of age, but no differences were detected between fiber sources. At same ages, the relative length (cm/kg BW) of the pullets (P = 0.058 and P < 0.01, respectively) and tarsus (P = 0.079 and P < 0.05, respectively) was higher in pullets fed SBP than in pullets fed straw. Fiber inclusion, however, did not affect any of these traits at 17 wk of age. In summary, the inclusion of 2% straw at the expense (wt:wt) of the whole diet did not affect pullet performance at 17 wk of age. An increase in the level of straw from 2 to 4% reduced FCR but did not affect ADG. The inclusion of SBP, however, reduced pullet growth, with effects being more pronounced at the higher level., (© 2015 Poultry Science Association Inc.)

The effect of sex, source of saturated fat (lard v. palm oil) and glycerol inclusion in the fattening diet on composition and fatty acid positional distribution in the triglyceride molecule was studied in pigs from 78 to 110 kg BW. Average daily gain and carcass characteristics, including ham and loin weight, were not affected by dietary treatment but sex affected backfat depth (P < 0.01). A significant interaction between sex and glycerol inclusion was observed; dietary glycerol increased lean content in gilts but not in barrows (P < 0.05 for the interaction). Individual and total saturated fatty acid (SFA) concentrations were greater in barrows than in gilts. In contrast, the concentration of total polyunsaturated fatty acids (PUFA) and of C18:2n-6, C18:3n-3, C20:3n-9 and C20:4n-6 in the intramuscular fat (IMF) was higher (P < 0.05) in gilts than in barrows. Sex did not affect total monounsaturated fatty acids (MUFA) concentration in the IMF. The proportion of SFA in the subcutaneous fat (SF) was higher in barrows than in gilts (P < 0.001). Within the individual SFA, sex affected only the concentrations of C14:0 and C16:0 (P < 0.001). Dietary fat did not affect total SFA or PUFA concentrations of the IMF but the subcutaneous total MUFA concentration tended to be higher (P = 0.079) in pigs fed lard than in pigs fed palm oil. Dietary glycerol increased total MUFA and C18:1n-9 concentration in the IMF and increased total MUFA and decreased C18:2n-6, C18:3n-3 and total PUFA concentrations in the SF. The data indicate that altering the fatty acid composition of the triglyceride molecule at the 2-position, by dietary intervention during the fattening phase, is very limited.

The effects of the main cereal and feed form of the rearing phase diets on growth performance, gastrointestinal tract characteristics, and body traits were studied in brown-egg pullets from hatch to 17 wk of age. Eight dietary treatments that were a combination of 2 main cereals (corn vs. wheat) and 4 feeding programs were used. The feeding program consisted in feeding crumbles from 0 to 5, 0 to 10, or 0 to 17 wk of age followed by mash until 17 wk, or feeding mash continuously from 0 to 17 wk. Each treatment was replicated 9 times. From hatch to 17 wk of age, pullets fed corn had similar ADG but poorer feed conversion ratio (FCR; P < 0.001) than pullets fed wheat. Also, pullets fed crumbles continuously (0 to 17 wk) had greater ADG (12.3 vs. 11.5 g; P < 0.001) and better FCR (4.21 vs. 4.36; P < 0.001) than pullets feed mash continuously, with pullets that were changed at any age of the rearing period from crumbles to mash feeding showing intermediate results. At 17 wk of age, the relative weights (% BW) of the gastrointestinal tract and gizzard were greater in pullets fed corn than in pullets fed wheat (P < 0.01) but the relative length (cm/kg full BW) of the small intestine, body, and tarsus was not affected. Pullets fed crumbles continuously had lighter gizzards (P < 0.001), higher gizzard pH (P < 0.001), and were shorter (P < 0.01) than pullets fed mash continuously, with pullets fed the other 2 treatments being intermediate. In summary, wheat can be used in substitution of corn in pullet diets without any adverse effect on growth performance. Feeding crumbles improves pullet performance but hinders gizzard and gastrointestinal tract development. Growth performance, gastrointestinal tract, and body traits of the pullets re-adapt quickly to changes in feed form of the rearing diets., (© 2015 Poultry Science Association Inc.)

The influence of feed form and energy concentration of the diet on growth performance and the development of the gastrointestinal tract (GIT) was studied in brown-egg laying pullets. Diets formed a 2 x 5 factorial with 2 feed forms (mash vs. crumbles) and 5 levels of energy differing in 50 kcal AMEn/kg. For the entire study (0 to 17 wk of age) feeding crumbles increased ADFI (52.9 vs. 49.7 g; P < 0.001) and ADG (12.7 vs. 11.6 g; P < 0.001) and improved feed conversion ratio (FCR; 4.18 vs. 4.27; P < 0.001). An increase in the energy content of the diet decreased ADFI linearly (P < 0.001) and improved FCR quadratically (P < 0.01) but energy intake (kcal AMEn/d) was not affected. BW uniformity was higher (P < 0.05) in pullets fed crumbles than in those fed mash but was not affected (P > 0.05) by energy content of the diet. At 5, 10, and 17 wk of age, the relative weight (RW, % BW) of the GIT and the gizzard, and gizzard digesta content were lower (P < 0.05 to P < 0.001) and gizzard pH was higher (P < 0.05 to P < 0.001) in pullets fed crumbles than in pullets fed mash. Energy concentration of the diet did not affect any of the GIT variables studied. In summary, feeding crumbles improved pullet performance and reduced the RW of the GIT and gizzard, and increased gizzard pH at all ages. An increase in the energy content of the diet improved FCR from 0 to 17 wk of age. The use of crumbles and the increase in the AMEn content of the diet might be used adventageously when the objetive is to increase the BW of the pullets. However, crumbles affected the development and weight of the organs of the GIT, which might have negative effects on feed intake and egg production at the beginning of the egg laying cycle., (© 2015 Poultry Science Association Inc.)

Two experiments were conducted to study the effects of inclusion of additional fiber in the Phase I diet on growth performance and nutrient digestibility in piglets reared under "optimal" or "poor" hygienic conditions. In both experiments, the design was completely randomized with a control diet that contained 2.2% crude fiber and 8 additional isonutritive diets that included 2.5 or 5.0% of sugar beet pulp (SBP), straw, oat hulls (OH), or wheat middlings (WHM). Preplanned polynomial contrasts were used to study the effects of 1) fiber inclusion (control diet vs. average of the 8 fiber-containing diets), 2) source of fiber, 3) level of fiber, and 4) interaction between source and level of fiber. In Exp. 1 (clean barn), fiber inclusion increased ( < 0.01) the incidence of postweaning diarrhea (PWD) and reduced ( < 0.05) feed efficiency and apparent total tract digestibility (ATTD) of all nutrients except that of CP, which was not affected. Piglet performance was not affected by source or level of dietary fiber. The ATTD of all nutrients decreased ( < 0.05) as the level of fiber increased and was lower in pigs fed straw or OH than in pigs fed SBP or WHM. The apparent ileal digestibility of GE and DM decreased ( < 0.05) with fiber inclusion, a reduction that was more pronounced ( < 0.05) with straw or SBP than with OH inclusion, with WHM inclusion being intermediate. Fiber inclusion did not affect villous height to crypt depth ratio of the ileum mucosa. The inclusion of 5% of a fiber source increased and counts in the cecum ( < 0.001) but the to ratio was not affected. In Exp. 2 (dirty barn), fiber inclusion did not affect piglet performance but tended to increase PWD ( = 0.07). Also, fiber inclusion reduced ( < 0.05) the ATTD of all dietary components except that of CP, which was not affected. Source and level of fiber did not affect ATTD of nutrients except for DM, which was greater for pigs fed SBP than for pigs fed straw ( < 0.05). In conclusion, in the current research, pigs reared under optimal hygienic conditions had lower incidence of PWD, better growth performance, and greater DM and GE digestibility than pigs reared under poor hygienic conditions. An excess of dietary fiber was more detrimental for all these traits in piglets reared under optimal hygienic conditions. The effects of the source and level of fiber on piglet performance was limited in the 2 experiments.

The effects of fiber inclusion, feed form, and energy concentration of the diet on the growth performance of pullets from hatching to 5 wk age were studied in 2 experiments. In Experiment 1, there was a control diet based on cereals and soybean meal, and 6 extra diets that included 2 or 4% of cereal straw, sugar beet pulp (SBP), or sunflower hulls (SFHs) at the expense (wt/wt) of the whole control diet. From hatching to 5 wk age fiber inclusion increased (P<0.05) ADG and ADFI, and improved (P<0.05) energy efficiency (EnE; kcal AMEn/g ADG), but body weight (BW) uniformity was not affected. Pullets fed SFH tended to have higher ADG than pullets fed SBP (P=0.072) with pullets fed straw being intermediate. The feed conversion ratio (FCR) was better (P<0.05) with 2% than with 4% fiber inclusion. In Experiment 2, 10 diets were arranged as a 2×5 factorial with 2 feed forms (mash vs. crumbles) and 5 levels of AMEn (2,850, 2,900, 2,950, 3,000, and 3,050 kcal/kg). Pullets fed crumbles were heavier and had better FCR than pullets fed mash (P<0.001). An increase in the energy content of the crumble diets reduced ADFI and improved FCR linearly, but no effects were detected with the mash diets (P<0.01 and P<0.05 for the interactions). Feeding crumbles tended to improve BW uniformity at 5 wk age (P=0.077) but no effects were detected with increases in energy concentration of the diet. In summary, the inclusion of moderate amounts of fiber in the diet improves pullet performance from hatching to 5 wk age. The response of pullets to increases in energy content of the diet depends on feed form with a decrease in feed intake when fed crumbles but no changes when fed mash. Feeding crumbles might be preferred to feeding mash in pullets from hatching to 5 wk age., (© 2015 Poultry Science Association Inc.)

In total, 540 crossbred pigs with an initial body weight of 28.5kg were used to investigate the effects of the net energy (NE) content (2.29, 2.33, 2.37, 2.41 and 2.45 Mcal/kg) of the diet on growth performance and carcass and meat quality traits of gilts, boars and immunocastrated males (IMC). An increase in dietary NE increased NE intake and decreased feed conversion ratio linearly. The IMC pigs showed greater feed intake and average daily gain than gilts and boars. Backfat depth increased and chilled and trimmed ham yield decreased, as the dietary NE increased. Backfat depth was greater for gilts and IMC than for boars. Also, gilts had greater carcass and loin yields than boars and IMC. Diets with the greater NE content were more appropriate for the production of heavy pigs. However, the economic interest of this practice needs further assessment., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

The influence of source and level of inclusion of raw glycerin (GLYC) in the diet on growth performance, digestive traits, total tract apparent retention (TTAR), and apparent ileal digestibility of nutrients was studied in broilers from 1 to 21 d of age. There was a control diet based on corn and soybean meal and 8 additional diets that formed a 2 × 4 factorial with 2 sources of GLYC and 4 levels of inclusion (2.5, 5.0, 7.5, and 10%). The GLYC used were obtained from the same original batch of soy oil that was dried under different processing conditions and contained 87.5 or 81.6% glycerol, respectively. Type of processing of the GLYC did not affect any of the variables studied except DM and organic matter retention (P < 0.05) that was higher for the 87.5% glycerol diet. From d 1 to 21, feed conversion ratio (FCR) improved linearly (L, P ≤ 0.01) as the GLYC content of the diet increased, but ADG was not affected. On d 21, the relative weight (% BW) of the liver and the digestive tract increased (L, P < 0.01) as the level of GLYC in the diet increased, but lipid concentration in the liver was not affected. The TTAR of DM and organic matter increased quadratically (Q, P < 0.05) and the AME(n) content of the diet increased linearly (L, P < 0.01) with increases in dietary GLYC. Also, the apparent ileal digestibility of DM (L, P < 0.05; Q, P = 0.07) and gross energy (L, P < 0.01) increased as the GLYC content of the diet increased. It is concluded that raw GLYC from the biodiesel industry can be used efficiently, up to 10% of the diet, as a source of energy for broilers from 1 to 21 d of age and that the energy content of well-processed raw GLYC depends primarily on its glycerol content., (©2014 Poultry Science Association Inc.)

The effects of inclusion in the diet of different sources of soya bean meal (SBM) on growth performance, total tract apparent digestibility (TTAD) and apparent ileal digestibility (AID) of major dietary components and mucosal ileum morphology were studied in Iberian pigs weaned at 30 days of age. From 30 to 51 days of age (phase I), there was a control diet based on regular soya bean meal (R-SBM; 44% CP) of Argentina (ARG) origin and five extra diets in which a high-protein soya bean meal (HP-SBM; 49% CP) of the USA or ARG origin, either ground (990 μm) or micronized (60 μm), or a soya protein concentrate (SPC; 65% CP) substituted the R-SBM. From 51 to 61 days of age (phase II), all pigs were fed a common commercial diet in mash form. The following pre-planned orthogonal contrasts were conducted: (1) R-SBM v. all the other diets, (2) SPC v. all the HP-SBM diets, (3) micronized HP-SBM v. ground HP-SBM, (4) HP-SBM of ARG origin v. HP-SBM of US origin and (5) interaction between source and the degree of grinding of the HP-SBM. Dietary treatment did not affect growth performance of the pigs at any age but from 30 to 51 days of age, post weaning diarrhoea (PWD) was higher (P<0.001) and the TTAD and AID of all nutrients were lower for pigs fed the R-SBM diet than for pigs fed the HP-SBM or the SPC diets. However, no differences between the HP-SBM and the SPC containing diets were detected for any trait. The TTAD of organic matter (P=0.07) and gross energy (GE) (P=0.05) tended to be higher for the micronized HP-SBM than for the ground HP-SBM and that of GE was higher (P<0.05) for US meal than for the ARG meal. Pigs fed R-SBM had lower villus height (P<0.01) than pigs fed HP-SBM or SPC but no differences in ileal mucosal morphology were detected between SPC and HP-SBM containing diets. It is concluded that feeding the HP-SBM or SPC-reduced PWD and improved nutrient digestibility and ileal morphology as compared with feeding the R-SBM, but had no effect on pig performance. The inclusion in the diet of added value soya products (micronized SBM or SPC) in substitution of the R-SBM increased the TTAD of all nutrients and reduced PWD but had no advantage in terms of growth performance over the use of ground HP-SBM.

The effect of including hydrolyzed porcine mucosa sprayed into soybean meal (HPM) in the diet was studied in broilers. In experiment 1 (pen study), 1,080 one-day-old chicks were used in a completely randomized design with 8 treatments arranged as a 4 × 2 factorial with 4 levels of HPM (0, 2.5, 5.0, and 7.5%) and 2 levels of Lys (1.23 and 1.38%). From d 1 to 22, HPM inclusion quadratically improved BW gain (BWG, P < 0.01) and feed conversion ratio (FCR, P < 0.01). From d 1 to 8, birds fed 1.38% Lys had higher BWG (P < 0.05) and better FCR (P < 0.05) than birds fed 1.23% Lys but only a trend (P < 0.08) for improved BWG was detected from d 1 to 22. From d 22 to 37, a period in which all birds received a common finisher diet, growth performance was not affected by the previous starter diet. In experiment 2 (battery study), birds were fed for 37 d the same diets used in the starter period of experiment 1. Broilers fed HPM had higher BWG (linear, P < 0.05; Quadratic, P < 0.05) than birds fed control diet, and birds fed 1.38% Lys had higher BWG (P < 0.01) than birds fed 1.23% Lys. From d 1 to 22, BWG (P < 0.05) and ADFI (P < 0.01) increased quadratically and FCR improved linearly (P < 0.05) with HPM inclusion. Also in this period, BWG was higher at the higher Lys level (P < 0.01). Diet did not affect intestinal histomorphology of broilers on d 8 or nutrient retention on d 22. We conclude that the inclusion of 2.5 to 5% HPM in the diet improved growth performance of broilers from d 1 to 22. An increase in Lys from 1.23 to 1.38% improved growth performance up to 15 d of age, but not thereafter. Diet did not affect villus histomorphology or nutrient retention of the small intestine.

In total, 240 pigs were used to compare growth performance and carcass quality traits of immunocastrated males (ICM), surgically castrated males (SCM), and intact females (IF) of crossbreds from Large White × Landrace females and Duroc (DU) or Pietrain (PI) sires destined to the dry-cured industry. Between the 2 Improvac injections (87 and 137 d of age), ICM and IF had less ADG than SCM (P < 0.01). Also, ICM ate less feed than IF and both less than SCM (2.33, 2.55, and 2.77 kg/d; respectively; P < 0.001) and consequently, ICM had better G:F than SCM and IF (P < 0.001). From second Improvac injection to slaughter (137 to 164 d of age), ICM were more efficient than IF and both more efficient than SCM (0.346, 0.323, and 0.300 g/g; respectively; P < 0.001). The differences in growth performance among genders observed in this period were more pronounced for the PI than for the DU crossbreds (P < 0.05 for the interaction). For the entire experimental period (87 to 164 d of age), gender did not affect ADG for DU crossbreds but for PI crossbreds ICM and SCM had greater ADG than IF (P < 0.05 for the interaction). The ICM pigs had better feed efficiency (0.406, 0.364, and 0.380; g/g; P < 0.001) and lower carcass yield (76.6, 78.1, and 78.8%; P < 0.001) than SCM or IF. Carcasses from IF were leaner than carcasses from SCM with carcasses from ICM being intermediate (P < 0.01). Ham and loin (P < 0.001) yields were greater for IF than for ICM or SCM. Intramuscular fat content was lower for IF than for SCM with that of ICM being intermediate (3.5 vs. 3.9 and 3.7%; P < 0.05). Cumulatively, crossbreds from DU sires had greater ADG (1.167 vs. 0.986 kg/d; P < 0.001) and ADFI (3.07 vs. 2.56 kg/d; P < 0.001) and more intramuscular fat (P < 0.001) but less ham and loin yields (P < 0.01) than crossbreds from PI sires. It is concluded that growth performance was better but carcass yield less for ICM than for SCM and IF. Intramuscular fat content in LM was less for IF than for SCM with ICM intermediate. Crossbreds from Duroc sires grew faster and had more intramuscular fat but less ham yield than crossbreds from Pietrain sires. Therefore, ICM should be preferred to SCM and Duroc crossbreds should be preferred to Pietrain crossbreds to produce carcasses destined to the production of primal cuts for the dry-cured industry.

The effects of autoclaving 2 varieties of micronized (fine grinding) pea protein concentrate (PPC) on the ileal digestibility (ID) of CP and amino acids (AA) were studied in broilers. There was a control diet based on fermented soybean meal (FSBM) and 4 extra diets in which the FSBM was substituted on a CP basis by PPC from 2 different pea cultivars (PPC-1 and PPC-2), either unheated or autoclaved. Chicks were fed a common diet from 1 to 17 d of age and, then, their respective experimental diets from 18 to 21 d of age. Each treatment was replicated 6 times. Autoclaving reduced trypsin inhibitor activity (TIA) but had little effect on the saponin content of the PPC. The apparent ID (AID) of CP was similar for the FSBM and the unheated PPC and lower for both than for the autoclaved PPC. Autoclaving improved (P < 0.001) the AID of CP (87.6 vs. 82.2%) and most indispensable AA (e.g., 92.1 vs. 88.8% for Lys and 83.6 vs. 76.5% for Thr) of the PPC. The improvement in CP and AA digestibility with autoclaving varied with the PPC used and was consistent with the reduction in TIA observed (9.4 to 2.8 mg/g for PPC-1 vs. 9.1 to 5.3 mg/g for PPC-2). The standardized ID (SID) of most indispensable AA was similar for the FSBM and the PPC-2 and higher for both than for the PPC-1 (P < 0.05). For Lys, the lowest SID value was observed for the FSBM and the highest for the PPC-2 either unheated or autoclaved. It is concluded that the ID of the AA of the PPC improved with heating and was in general higher for the autoclaved PPC than for the FSBM. Consequently, heat processed PPC is a good alternative to FSBM and unheated PPC in starter diets for broilers.

Two experiments were conducted to determine the apparent ileal digestibility (AID) of the amino acids (AA) of 4 commercial soybean meals (SBM) from the United States (USA-1, 48.1% CP and USA-2, 46.2% CP), Brazil (BRA, 47.6% CP), and Argentina (ARG, 46.3% CP) and the effects of the inclusion of these SBM in diets in mash, crumble, or pellet form on growth performance, total tract apparent retention of nutrients, and digestive organ size in broilers reared in cages from 1 to 25 d of age. In experiment 1, the AID of Lys was higher (P < 0.05) for the USA-2 than for the BRA SBM, with the SBM from USA-1 and ARG being intermediate. In experiment 2, 12 diets were arranged as a 3 × 4 factorial with 3 feed forms (mash, crumbles, and pellets) and the 4 sources of SBM used in experiment 1. The feeds were isonutritive and the AID of the AA of the SBM obtained in experiment 1 was used for diet formulation. Broilers fed mash had lower (P < 0.001) ADFI and ADG and poorer (P < 0.001) feed-to-gain ratio than broilers fed crumbles or pellets but source of SBM did not affect growth performance. Nitrogen retention was higher (P < 0.01) in birds fed mash than in birds fed crumbles or pellets at all ages. The total tract apparent retention of nutrients was lower (P < 0.05) for the BRA and ARG SBM diets than for the USA-1 and USA-2 SBM diets. Gizzard empty relative weight (% BW) was higher and gizzard pH lower for broilers fed mash than for broilers fed crumbles or pellets (P < 0.001). The results indicate that crumbling or pelleting of the diets improved growth performance of broilers from 1 to 25 d of age. Diets formulated with analyzed rather than calculated AID of AA of the SBM sources resulted in similar broiler performance.

The influence of CP content and ingredient complexity, feed form, and duration of feeding of the Phase I diets on growth performance and total tract apparent digestibility (TTAD) of energy and nutrients was studied in Iberian pigs weaned at 28 d of age. There were 12 dietary treatments with 2 type of feeds (high-quality, HQ; and low-quality, LQ), 2 feed forms (pellets vs. mash), and 3 durations (7, 14, and 21 d) of supply of the Phase I diets. From d 7, 14, or 21 (depending on treatment) to d 35, all pigs received a common diet in mash form. Each treatment was replicated 3 times (6 pigs/pen). For the entire experiment, ADG (P < 0.05) and ADFI (P < 0.01) were less with the HQ than the LQ Phase I diets, but G:F was not affected. Pelleting of the Phase I diets did not affect ADG but improved G:F (P < 0.01). Feeding the Phase I diets from d 0 to 21 improved G:F (P < 0.05) but decreased ADG (P < 0.01) as compared with 7 or 14 d of feeding. Postweaning diarrhea (PWD) tended to be greater (P = 0.06) for pigs fed the HQ diets than pigs fed the LQ diets and pigs fed pellets than those fed mash (P < 0.001). Also, PWD was greater for pigs fed the Phase I diet for 14 or 21 d than those fed the diet for 7 d (P < 0.01). From d 0 to 21, ADG and G:F were not affected (P > 0.10) by feed quality, but feeding pellets or increasing the duration of feeding the Phase I diets improved G:F (P < 0.01). Also, in this period, PWD was greater with pellets than with mash and for pigs fed the Phase I diets for 14 or 21 d than for pigs fed the diet for only 7 d (P < 0.01). From d 21 to 35, pigs previously fed the LQ diet had greater ADG than pigs fed the HQ Phase I diets (P < 0.001). Also, pigs fed the Phase I diets for 21 d had decreased ADG (P < 0.05) and ADFI (P < 0.001) and reduced G:F (P < 0.05) than pigs fed these diets for 7 or 14 d. Organic matter digestibility was greater for pigs fed the HQ Phase I diets than pigs fed the LQ Phase I diets (P < 0.05). Pelleting improved TTAD of all nutrients (P < 0.01). It is concluded that HQ Phase I diets increased TTAD of nutrients but not feed efficiency of Iberian pigs from d 0 to 35. Also, pelleting improved energy and nutrient digestibility and feed efficiency. Increasing the duration of supply of the Phase I diets from 7 to 21 d improved feed efficiency but reduced ADG. Therefore, the use of LQ Phase I diets in pellet form for no more than 7 d after weaning is recommended in Iberian pigs.

A total of 288 piglets weaned at 28 d and weighing 7.6 ± 0.2 kg were used in a 35-d experiment to evaluate the effect of CP content (44% vs. 49% CP) of soybean meal (SBM), micronization (fine grinding) of the 49% CP SBM (HP-SBM), and soy protein concentrate (SPC; 65% CP) on total tract apparent digestibility (TTAD) and growth performance. In phase I (d 0 to 21 of experiment), there was a positive control diet that included 6.5% of CP from a SPC with 65% CP and a negative control diet that supplied the same amount of CP as regular SBM (R-SBM) with 44% CP. The other 4 diets included the same amount of dietary CP from 2 different sources of HP-SBM that were either ground (990 μm) or micronized (60 μm). All diets were isonutritive, and the main difference was the source of SBM used. Each treatment was replicated 8 times (6 pigs per pen). In phase II (d 21 to 35), all pigs were fed a common commercial starter diet. For the entire phase I, the type of soy product did not affect growth performance of the pigs. However, from 0 to 7 d of experiment, pigs fed the micronized HP-SBM had better G:F (1.11 vs. 0.98; P<0.05) than piglets fed the ground HP-SBM. Also, from 7 to 14 d of experiment, ADFI tended to be greater (P=0.08) for pigs fed the micronized HP-SBM than for piglets fed the ground HP-SBM. During phase II (all the pigs received the same diet), no differences among treatments were observed. In general, TTAD of nutrients at 7 d of experiment was greater for the SPC than the R-SBM diet, with the HP-SBM diets being intermediate. The TTAD of CP was greater (83.8% vs. 81.9%; P≤0.01) for the SPC diet than the average of the SBM diets. Also, the digestibility of OM and DM was greater (P<0.01) for the HP-SBM either ground or micronized than the R-SBM diet. Micronization of the HP-SBM did not affect nutrient digestibility. It is concluded that when the R-SBM is substituted by SPC, CP digestibility is improved, but no effects are observed on growth performance. The use of the HP-SBM in substitution of the R-SBM in the diet improved nutrient digestibility but did not affect piglet performance. The inclusion of micronized HP-SBM in the diet improved G:F during the first week postweaning but did not affect TTAD of nutrients. In general, the inclusion of added-value soy products (SPC or micronized SBM) in the diet presents little advantage in terms of growth performance over the use of HP-SBM in pigs weaned at 28 d of age.

The effects of inclusion of cellulose or inulin as a source of dietary fiber and CP content of the diet on hepatic fat deposition were investigated in hens fed restricted or close to ad libitum consumption. There were 12 dietary treatments forming a 2 × 3 × 2 factorial with 2 feeding regimens [restricted and liberal (close to ad libitum consumption; LIB)], 3 fiber sources (control, 3% inulin, and 3% cellulose), and 2 levels of CP (14.5 and 17.4%). Hens were assigned in groups of 6 to 60 floor pens. From 43 to 55 wk of age, hens fed LIB showed increased activity of the hepatic malic enzyme (MalE; P < 0.01), which led to an increase (P < 0.001) in liver weight and hepatic lipid deposition and was associated with enhancements (P < 0.05) in plasma levels of glucose, triglyceride, total cholesterol, and low-density lipoprotein cholesterol. Abdominal fat deposition and BW of the hens increased (P < 0.001) with liberal feeding. Inclusion of inulin in the diet reduced (P < 0.05) liver and abdominal fat weight, whereas cellulose inclusion decreased (P < 0.05) feed intake, abdominal fat, and BW. An increase in CP content of the diet from 14.5 to 17.4% reduced MalE activity (P < 0.001), liver weight (P < 0.001), and the accumulation of lipids and cholesterol in the liver, as well as plasma triglyceride concentration and abdominal fat pad weight (P < 0.05). It is concluded that fiber inclusion reduced abdominal fat and liver weight, with effects being more pronounced with cellulose than with inulin. An increase in dietary CP reduced MalE activity and alleviated hepatic and plasma lipid concentration; therefore, it might be a practical approach to reduce the incidence of obesity-linked problems in broiler breeder hens. The combination of high-CP diets and the inclusion of a fiber source did not suppress liver lipid content over that observed with the high-CP diet, exclusively.

A 12-wk experiment was conducted to study the effects of feeding regimen, inclusion of a fiber source, and CP content of the diet on performance of broiler breeder hens. In total, 360 hens and 60 males, 43 wk of age, were assigned to 60 floor pens (6 hens and 1 male each). There were 12 treatments arranged factorially with 2 feeding regimens [restricted (R) and liberal feeding (close to ad libitum consumption; LIB)], 3 sources of fiber (0, 3% inulin, and 3% cellulose), and 2 levels of CP (14.5 and 17.4%). No interactions among main effects were observed for any of the traits studied, and therefore, only main effects are presented. Body weight, liver weight, and abdominal fat weight were higher (P < 0.001) for the LIB than for the R-fed hens. However, egg production (P < 0.001), fertility index (P < 0.05), and percentage of hatch (P < 0.01) were lower for LIB than for R hens. The weights of ovaries (P < 0.05) and the size of the first preovulatory follicle (P < 0.05) were higher for the LIB than for the R hens. Also, egg yolk, egg weight, and BW of the hatching chicks were higher (P < 0.001) for the LIB hens. The inclusion of a fiber source in the diet decreased (P < 0.05) feed intake, BW gain, absolute liver and abdominal fat weight, and egg yolk weight, with effects being more pronounced (P < 0.05) with cellulose than with inulin. Hens fed additional fiber produced more (P < 0.05) eggs that were more fertile (P < 0.05) than control hens. Crude protein content of the diet did not affect hen performance but reduced (P < 0.01) the relative weight of the liver, ovary, and abdominal fat. It is concluded that the inclusion of inulin or cellulose in the diet improved hen performance and that an increase in dietary CP reduced obesity in broiler breeder hens.

The influence of AME(n) concentration of the diet on productive performance and egg quality traits was studied in Hy-Line brown egg-laying hens differing in initial BW from 24 to 59 wk of age. Eight treatments were arranged factorially with 4 diets varying in energy content (2,650, 2,750, 2,850, and 2,950 kcal of AME(n)/kg) and 2 initial BW of the hens (1,733 vs. 1,606 g). Each treatment was replicated 5 times (13 hens per replicate), and all diets had similar nutrient content per unit of energy. No interactions between energy content of the diet and initial BW of the hens were detected for any trait. An increase in energy concentration of the diet increased (linear, P < 0.05; quadratic P < 0.05) egg production, egg mass, energy efficiency (kcal of AME(n)/g of egg), and BW gain (P < 0.05) but decreased ADFI (linear, P < 0.001) and feed conversion ratio per kilogram of eggs (linear, P < 0.01; quadratic P < 0.01). An increase in energy content of the diet reduced Haugh units and the proportion of shell in the egg (P < 0.01). Feed intake (114.6 vs. 111.1 g/hen per day), AME(n) intake (321 vs. 311 kcal/hen per day), egg weight (64.2 vs. 63.0 g), and egg mass (58.5 vs. 57.0 g) were higher for the heavier than for the lighter hens (P < 0.01), but feed conversion ratio per kilogram of eggs and energy efficiency were not affected. Eggs from the heavier hens had a higher proportion of yolk and lower proportion of albumen (P < 0.01) and shell (P < 0.05) than eggs from the lighter hens. Consequently, the yolk-to-albumen ratio was higher (P < 0.001) for the heavier hens. It is concluded that brown egg-laying hens respond with increases in egg production and egg mass to increases in AME(n) concentration of the diet up to 2,850 kcal/kg. Heavy hens had higher feed intake and produced heavier eggs and more egg mass than light hens. However, feed and energy efficiency were better for the lighter hens.

In total, 3,120 broilers were used to study the effects of feed form and source of soybean meal (SBM) of the diet on growth performance. From 1 to 21 d of age, there were 12 treatments arranged factorially with 3 feed forms (mash, crumbles, and pellets) and 4 commercial sources of SBM that differed in the CP content [48.1 and 46.2% CP from the United States (USA-1 and USA-2), 47.6% CP from Brazil (BRA), and 46.3% CP from Argentina (ARG)]. From 21 to 42 d of age, diets were fed as pellets. Diets were formulated assuming that all SBM had similar digestible amino acid content per unit of CP. From 1 to 21 d of age, chicks fed crumbles or pellets had higher (P < 0.001) ADG than chicks fed mash. Also, chicks fed pellets had better (P < 0.001) feed-to-gain ratio (F:G) than chicks fed crumbles, and both were better than chicks fed mash. However, from 21 to 42 d of age, F:G was best (P < 0.001) for chicks previously fed mash. For the entire experimental period, broilers that were fed crumbles or pellets from 1 to 21 d of age had higher (P < 0.001) ADG than broilers that were fed mash. Also, broilers that were fed pellets had better (P < 0.05) F:G than broilers fed mash, with broilers fed crumbles being intermediate. Broilers fed the USA-2 meal had higher (P < 0.01) ADG than broilers fed the BRA or the ARG meals, with broilers fed the USA-1 meal being intermediate. Feed efficiency tended (P = 0.07) to be hindered in broilers fed the BRA meal. The results show that pelleting improved growth performance of broilers from 1 to 42 d of age with effects being less evident at 42 d than at 21 d of age. Source of SBM affected growth performance suggesting the need for a better control of chemical composition and quality of this ingredient before diet formulation.

A trial was conducted to study the influence of CP and fat content of the diet on performance and egg quality traits of brown egg-laying hens from 22 to 50 wk of age. The experiment was conducted as a completely randomized design with 8 treatments arranged factorially with 4 diets and 2 initial BW of the hens (1,592 vs. 1,860 g). Three of these diets differed in the CP content (16.5, 17.5, and 18.5%) and included 1.8% added fat. The fourth diet also had 18.5% CP but was supplemented with 3.6% fat instead of 1.8% fat. Each treatment was replicated 4 times, and the experimental unit consisted of 21 hens allocated into groups of 7 in 3 adjacent cages. All diets were isocaloric (2,750 kcal of AME/kg) and met the recommendations of brown egg-laying hens for digestible Arg, Ile, Lys, Met, Thr, Trp, TSAA, and Val. Productive performance and egg quality were recorded by replicate every 28 d. For the entire experimental period, diet did not affect any of the productive performance traits studied, but the heavier hens had higher ADFI (120.6 vs. 113.9 g; P < 0.001), egg production (92.5 vs. 89.8%; P < 0.01), and egg weight (64.9 vs. 62.4 g; P < 0.001) than the lighter hens. Initial BW did not affect feed conversion per kilogram of eggs or hen mortality, but BW gain was higher (289 vs. 233 g; P < 0.01) and feed conversion ratio per dozen of eggs was better (1.52 vs. 1.57; P < 0.01) for the lighter than for the heavier hens. None of the egg quality variables studied was affected by dietary treatment or initial BW of the hens. It is concluded that brown egg-laying hens, irrespective of their initial BW, do not need more than 16.5% CP to maximize egg production, provided that the diet meets the requirements for key indispensable amino acids. Heavier hens produce more eggs that are larger than lighter hens but feed efficiency per kilogram of eggs is not affected.

The effects of gender and castration of females (IF, intact females; CF, castrated females; CM, castrated males) on performance and carcass and meat quality were studied in crossbred pigs (Landrace×Large White dams×Duroc sires) slaughtered at 119.2 (experiment 1) or 131.6 (experiment 2) kg body weight. Intact females had better feed conversion and less carcass fat than CF and CM. Trimmed shoulder yield was higher for CM than for CF with IF being intermediate. Primal cut yield and meat quality were similar for all treatments. Proportion of linoleic acid in backfat was lower in CF than in IF or CM and the differences were significant when pigs were slaughtered at 131.6kg. The higher fat content and the fatty acid profile favor the use of castrated females and males over intact females for the production of heavy pigs destined to the dry-cured industry., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

An experiment was conducted to study the effects of inclusion of a wheat cultivar (high in nonstarch polysaccharides) and xylanase supplementation of the diet on productive performance, pH of the gastrointestinal tract, nutrient retention, and intestinal enzyme activity of Hy-Line W-36 laying hens from 25 to 47 wk of age. The experiment was completely randomized with 8 treatments arranged factorially with 4 levels of wheat (0, 23, 46, and 69%) that corresponded to a dietary arabinoxylan content of 3.0, 3.3, 3.6, and 3.9%, with or without xylanase supplementation. Each treatment was replicated 5 times. For the entire experimental period, egg weight (P < 0.05) and egg mass (P < 0.01) were reduced and the feed conversion ratio was hindered (P < 0.05) with increased levels of wheat in the diet, but ADFI and egg production were not affected. Xylanase supplementation improved egg production (P < 0.05), egg mass (P < 0.01), and the feed conversion ratio (P < 0.01). Diet did not affect egg quality at any age, except for shell thickness at 47 wk that was improved with xylanase supplementation (P < 0.05). Digesta pH of the different organs of the gastrointestinal tract was not affected by wheat inclusion or xylanase supplementation. Ileal viscosity increased (P < 0.001) with wheat inclusion and decreased (P < 0.001) with xylanase supplementation at all ages. Fat digestibility (P < 0.001) decreased with increased levels of wheat but AME(n) content of the diets (P < 0.05) and nitrogen retention were not affected. Wheat inclusion increased (P < 0.001) amylase (33 wk), lipase (33 wk), and aminopeptidase (47 wk) activity in the duodenum as well as lipase activity in the jejunum at 47 wk of age. However, xylanase supplementation did not affect the activity of any of the enzymes studied. It is concluded that most of the negative effects of wheat inclusion in the diet were reduced or even disappeared with xylanase supplementation. Wheat with a high nonstarch polysaccharide content (Pishtaz cultivar) can be used at levels of up to 69% in laying-hen diets without negatively affecting bird performance, provided that feeds are supplemented with xylanase.

The influence of the main cereal and type of supplemental fat in the diet on productive performance and egg quality of the eggs was studied in 756 brown-egg laying hens from 22 to 54 wk of age. The experiment was conducted as a completely randomized design with 9 treatments arranged factorially, with 3 cereals (dented corn, soft wheat, and barley) and 3 types of fat (soy oil, acidulated vegetable soapstocks, and lard). Each treatment was replicated 4 times (21 hens/replicate). All diets were formulated to have similar nutrient content, except for linoleic acid, which ranged from 0.8 to 3.4% depending on the combination of cereal and fat source used. This approach allows for the estimation of the minimum level of linoleic acid in the diets that maximizes egg weight. Productive performance and egg-quality traits were recorded every 28 d, and the BW of the hens was measured individually at the beginning and at the end of the experiment. No significant interactions between main factors were detected for any of the variables studied. Egg production, egg weight, and egg mass were not affected by dietary treatment. Body weight gain was higher (P < 0.05) for hens fed corn or wheat than for hens fed barley, and also higher for hens fed lard than for hens fed soy oil or acidulated vegetable soapstocks. Egg quality was not influenced by dietary treatment, except for yolk color, which was greater (P < 0.001) for hens fed corn than for hens fed wheat or barley, and greater for hens fed lard than for hens fed soy oil or acidulated vegetable soapstocks. We concluded that brown-egg laying hens do not need more than 1.0% of linoleic acid in their diet (1.16 g/hen per d) to maximize egg production and egg size. The 3 cereals and the 3 fat sources tested can replace each other in the diet provided that the linoleic acid requirements to maximize egg size are met.

In total, 360 pigs slaughtered at 125 kg of BW and destined for the dry-cured industry were used to study the influence of sex and castration [immunocastrated males (IMC), surgically castrated males (CM), and intact females (IF)] in 2 terminal Large White sire lines [Top York (TY) and Tempo (TE)] on growth performance and carcass and meat quality. The female line was Large White × Landrace. The IMC pigs were immunized against gonadotropin-releasing factor (GnRF) with Improvac at 78 (experimental d 16) and 126 (experimental d 64, 48 d before slaughter) d of age. Each of the 6 treatments was replicated 6 times (10 pigs/pen). Through the day of the first Improvac injection (62 to 78 d of age), IMC and IF grew at a slower rate (P < 0.001) than CM with no differences (P = 0.95) in feed intake. The CM had greater G:F than IF, with IMC being intermediate (P < 0.01). From 78 to 126 d of age (between Improvac injections), the IMC pigs ate less feed (P < 0.001) and grew at a slower rate than CM, with IF being intermediate. The IMC pigs were more feed efficient than IF, and both were more efficient than CM (P < 0.001). However, from 126 to 174 d of age (from the second Improvac injection to slaughter), IMC pigs grew at a faster rate (P < 0.001) and were more efficient (P < 0.001) than IF and CM. Overall, IMC and CM pigs grew at a faster rate (P < 0.01) than IF, and IMC were more efficient than the other sexes (P < 0.001), but had reduced (P < 0.001) carcass yield compared with CM and IF. The IMC and IF pigs also had less (P < 0.001) backfat depth than CM. Intact females had greater (P < 0.01) loin yield but less intramuscular fat than IMC and CM and greater (P < 0.05) fresh and trimmed ham yields than CM, with IMC being intermediate. Crossbreds from TE sires grew at a faster rate (P < 0.001) than crossbreds from TY sires, but no differences (P = 0.23 and 0.14, respectively) were found for feed intake or efficiency. Crossbreds from TY produced greater (P < 0.05) fresh and trimmed ham yield, but less (P < 0.01) loin yield and intramuscular fat content than crossbreds from TE. In conclusion, IMC pigs are more efficient, but have less carcass yield than CM and IF. The intramuscular fat content is least for IF and similar for IMC and CM. Crossbreds from TE sires were larger and had greater intramuscular fat content, but slightly less trimmed ham yield compared with crossbreds from TY sires. Immunocastrated pigs can replace CM for the production of heavy pigs destined for the dry-cured industry. Because of increased carcass weight, crossbreds from TE sires may have an advantage over crossbreds from TY sires.

The effects of feeding corn or rice, either raw or heat processed (HP), on apparent total tract digestibility (ATTD) and apparent ileal digestibility (AID) of nutrients and on insulin and ghrelin concentrations in the serum were studied in young pigs. Pigs were weaned at approximately 23 ± 3 d of age and weighed 7.4 ± 1.2 kg. Each of the 4 treatments was replicated 9 times, and the experimental unit was a pig individually housed. Pigs (5 males and 4 females/treatment) were fed their respective diets ad libitum from 23 to 47 d of age. At 37 d of age, the effects of dietary treatments on the fasting and postprandial concentrations of insulin and total and acylated ghrelin were studied. The ATTD of OM, GE, and ether extract were, respectively, 4.3, 5.4, and 3.6% greater (P < 0.05) for the rice than for the corn diets, but CP digestibility was not affected. Similar results were observed for AID. Heat processing of the cereal increased (P < 0.05) the ATTD by 2.1% for OM, 3.2% for GE, 7.1% for ether extract, and 2.2% for CP and tended to increase the AID of CP (P = 0.06) and starch (P = 0.09). The postprandial serum insulin response was greater and was more prolonged in pigs fed raw rice than in pigs fed raw corn (P < 0.05). In addition, the effects of HP on serum insulin response were more pronounced with corn than with rice (cereal × HP, P < 0.05). Total ghrelin concentration was not affected by treatment, but acylated ghrelin was greater (P < 0.05) at 6 h postprandially in pigs fed rice than in pigs fed raw corn. Feeding rice and HP corn increased nutrient digestibility and insulin response in the early postprandial period and increased the acylated ghrelin response in the late postprandial period compared with feeding raw corn.

A total of 200 (Landrace × Large White dam × Pietrain × Large White sire) gilts of 50 ± 3 days of age (23.3 ± 1.47 kg BW) were used to investigate the effects of castration (intact gilt, IG v. castrated gilt, CG) and slaughter weight (SW; 106 v. 122 kg BW) on productive performance, carcass and meat quality. Four treatments were arranged factorially and five replicates of 10 pigs each per treatment. Half of the gilts were ovariectomized at 58 days of age (8 days after the beginning of the trial at 29.8 ± 1.64 kg BW), whereas the other half remained intact. The pigs were slaughtered at 106 or 122 kg BW. Meat samples were taken at Musculus longissimus thoracis at the level of the last rib and subcutaneous fat samples were taken at the tail insertion. For the entire experimental period, CG had higher (P < 0.05) BW gain and higher (P < 0.001) backfat and Musculus gluteus medius fat thickness than IG. However, IG had higher (P < 0.05) loin and trimmed primal cut yields than CG. Meat quality was similar for IG and CG but the proportion of linoleic acid in subcutaneous fat was higher (P < 0.001) for IG. Pigs slaughtered at 122 kg BW had higher (P < 0.001) feed intake and poorer feed efficiency than pigs slaughtered at 106 kg BW. An increase in SW improved (P < 0.001) carcass yield but decreased (P < 0.05) trimmed primal cut yield. Meat from pigs slaughtered at the heavier BW was redder (a*; P < 0.001) and had more (P < 0.01) intramuscular fat and less thawing (P < 0.05) and cooking (P < 0.10) loss than meat from pigs slaughtered at the lighter BW. In addition, pigs slaughtered at 122 kg BW had less (P < 0.01) linoleic acid content in subcutaneous fat than pigs slaughtered at 106 kg BW. Castration of gilts and slaughtering at heavier BW are useful practices for the production of heavy pigs destined to the dry-cured industry in which a certain amount of fat in the carcass is required. In contrast, when the carcasses are destined to fresh meat production, IG slaughtered at 106 kg BW is a more efficient alternative.