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Experiments were conducted to assess the effect of surfeit choline (CHOL) or betaine (BET) on growth performance and homocysteine (HCY) remethylation of young broilers fed graded levels of DL-Met (DLM) or 2-hydroxy-4-(methylthio) butanoic acid (HMB). In Experiment 1, a corn-peanut meal diet deficient in Met (0.25% digestible) and Cys (0.28% digestible) was fed; treatments were formulated to contain graded levels (0, 0.04, or 0.08%) of Met from DLM or 0.04% HMB (adjusted for 88% purity) that were fed in the presence or absence of surfeit isomethyl CHOL (0.25%) or BET (0.28%). In Experiment 2, identical treatments were used, but an additional level of HMB (0.08%) was fed, and the basal diet was adequate in Cys (0.43% digestible). There was no overall effect of CHOL or BET on growth performance in Experiments 1 and 2 (P > 0.05); a significant improvement (P < 0.05) in weight gain and feed efficiency did occur with CHOL and BET addition to the basal diet in Experiment 2. In both experiments, weight gain increased linearly (P < 0.05) with the addition of DLM or HMB. Slope ratio methodology was used to assess HMB efficacy in Experiment 2. In the presence of adequate Cys, HMB efficacy was 81.3%; addition of surfeit BET or CHOL had minimal effect on efficacy. The stable isotope study revealed that CHOL and BET addition to diets deficient in Met and Cys or Met alone increased HCY remethylation. It also showed that CHOL and BET have greater influence on folate-dependent remethylation of HCY (via Met synthase) than on BET-dependent remethylation (via BET-HCY methyltransferase) and that levels of CHOL and BET and type of S amino acid deficiency effect remethylation and HMB efficacy. [ABSTRACT FROM AUTHOR]

Influences of dietary levels of vitamin E fed to hens and their progeny, and routes of SRBC inoculation on antibody responses of diverse populations of chickens were studied. Populations were a commercial broiler sire line (C), 2 commercial broiler dam lines (A and B), and Leghorn lines selected for high (H) or low (L) antibody response to SRBC. Dams from lines A and B were fed diets supplemented with either 10 or 300 IU/kg of vitamin E, whereas dams from lines H and L received only the diet with 10 IU of vitamin E/kg. Progeny from matings of C males with A and B females as well as H and L females mated to males from their respective lines were hatched on the same day and fed diets supplemented with either 10 or 300 IU/kg of vitamin E. Breeders were the same age and eggs were incubated in the same machine. Chicks were inoculated on d 14 intravenously with 0.1 mL of a 0.5% suspension of SRBC or intramuscularly with 0.1 mL of a 25% suspension of SRBC. Antibody response was measured 6 and 14 d later. Chicks received a booster i.m. inoculation of 0.1 mL of 25% SRBC on d 28. Titers were again measured 6 and 14 d later. Level of vitamin E fed to dams did not affect progeny BW or plasma vitamin E levels. Although titers were higher following i.v. than i.m. inoculation, the degree of difference varied among stocks. Dietary vitamin E level interacted with inoculation route with a greater response to the higher than lower level of vitamin E for i.v., but there was no difference for i.m. There were stock ⊗ level of vitamin E and stock ⊗ route of inoculation interactions for secondary responses to SRBC inoculation. Stock rankings after the first inoculation were not predictive of the rankings after the second inoculation. The 30-fold increase in dietary level of vitamin E resulted in >12-fold differences in plasma levels of vitamin E. Overall, there was a stock-dependent influence of dietary vitamin E on growth and humoral antibody response. [ABSTRACT FROM AUTHOR]

Methionine is critical in amino acid nutrition for chickens, yet details of the flux of Met metabolites in the avian system are lacking. This study explored the interactions among dietary choline (CHO), betaine (BET), and sulfur amino acid levels on growth and hepatic homocysteine (HCY) remethylation. Graded levels (0, 0.07, 0.11, and 0.24%) of DL-Met were added to diets adequate in CR0 and deficient in sulfur amino acids (0.26% digestible Met, 0.26% digestible Cys). Each Met level was tested alone or with the addition of CHO (0.25%) or BET (0.28%). Broilers were reared from 8 to 22 d in raised wire floor battery cages, and the 12 dietary treatments were fed to 3 replicate pens containing 5 birds per pen. Weight gain and feed efficiency were maximized (P < 0.05) with addition of 0.11% supplemental Met, whereas feed intake was maximized (P < 0.05) with addition of 0.07% supplemental Met. Overall, growth parameters were not affected (P > 0.05) by CHO or BET addition. Hepatic tissue primed by the different dietary treatments was subjected to a newly developed stable isotope methodology and HPLC-mass spectrometry to quantify the impact of diet on HCY remethylation. Dietary Met level did not (P> 0.05) affect HCY remethylation, but remethylation through the Met synthase pathway was increased (P < 0.05) by addition of CHO or BET to diets containing deficient or excess levels of Met. Minimal changes in hepatic HCY remethylation through the betaine-homocysteine methyl transferase pathway occurred in response to dietary changes; therefore, data failed to support previous suggestions that BHMT might have a regulatory role when diets containing deficient or excess Met levels are fed. In contrast to previous suppositions based on enzyme activity, under most dietary conditions, the quantity of HCY remethylated by Met synthase appeared to exceed that remethylated by the alternate betaine-homocysteine methyltransferase pathway. [ABSTRACT FROM AUTHOR]

A 28-day battery cage study was conducted to test the efficacy of tannin-free grain sorghum varieties fed to Cobb 500 male broiler chickens (n = 512) and challenged with Eimeria maxima (EM) and Clostridium perfringens (CP). Birds were fed 1 of 8 treatments (corn, red/bronze, white/tan, or U.S. No. 2 sorghum) and were grouped by challenge method (challenged with EM/CP or unchallenged). On d 14, birds in the challenge group were orally inoculated with ∼5,000 oocysts of EM, and on d 19, 20, and 21, birds were given a broth culture of CP with ∼10 8 CFU/mL once daily. On d 21, three birds were scored for the degree/presence of necrotic enteritis (NE) lesions. Birds and feed were group weighed (d 0, 14, 21, and 28) to calculate average feed intake (FI), body weight gain (BWG), and adjusted feed conversion ratio (AdjFCR). Intestinal integrity was assessed through histological analysis of intestinal tissues, and change in transcriptome was determined using mRNA-sequencing on intestinal mucosa. Relative concentrations of secondary metabolites in grain sorghum were determined by LC-MS/MS analysis. Data were analyzed as a 2-way ANOVA with factors of treatment, challenge and their interaction. Regardless of challenge from 14 to 21 d, birds on the corn, white/tan, and U.S. No. 2 treatments were more efficient than those fed red/bronze treatment (P = 0.0026). From 14 to 28 d, BWG was significantly higher for the white/tan treatment (P = 0.024) compared to the red/bronze treatment. At 21 d, a significant interaction was observed for lesion score (P = 0.0001) in which, challenged birds fed red/bronze and white/tan treatments had reduced intestinal lesions compared to U.S. No. 2 and corn treatments. No differences among treatments were observed in jejunum morphology, but differential expression analysis showed an upregulation in defense response to bacteria and biotic stress in the challenged red/bronze treatment compared to the challenged corn. This study demonstrated improved gut health and minimal impact on growth and efficiency of broilers fed select grain sorghum varieties when challenged with EM/CP., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

An experiment was conducted to determine the effects of varying levels of dietary fat and protein in corn-soybean meal diets on body weight gain, feed consumption, and feed efficiency (gain:feed ratio) of Nicholas Large White male turkeys between 8 and 22 wk of age. Diets containing 0, 5, 10, or 15% added fat from one of three sources and 18, 21, or 24% protein were fed. At 12 and 16 wk of age, protein levels of all diets were decreased by 2%. A total of 917 turkeys in 36 pens was used. Additions of 5, 10, and 15% fat increased body weight gains 3.3, 7.5, and 6.0%, respectively. Feed consumption decreased 1.3% and feed efficiency increased 2.1% for each 1% fat added to the standard and high protein diets. The fat containing 15% free fatty acids and 1.5% moisture, impurities, and unsaponifiables (MIU) decreased feed consumption 1.5% and increased feed efficiency 2.3% for each 1% added fat, and the two fat sources containing 48% free fatty acids and 5% MIU decreased feed consumption 1.2 or 1.1% and increased feed efficiency 2.1 or 2.0% for each 1% added fat. The former fat source was estimated to contain 7.7% more metabolizable energy than the average of the latter two fat sources. Cumulative body weight gain, feed consumption, and feed efficiency decreased 13.2, 5.7, and 8.1%, respectively, from feeding low protein diets in comparison with results of feeding standard and high protein diets. Maximum increases in body weight gains were obtained with 10% added fat at all levels of protein.(ABSTRACT TRUNCATED AT 250 WORDS)

Five 7-day trials using 336, 24, 24, 40, and 40 Large White male turkeys when 7, 11, 15, 27, and 32 weeks of age, respectively, were conducted to determine the toxic effects of salinomycin. Salinomycin became more toxic as the age of the turkeys increased. When 7-week-old turkeys were fed diets containing 44 or 66 ppm salinomycin, only 1 of 84 died; when turkeys 27 or 32 weeks of age were fed those amounts, 13 of 20 died. Salinomycin at 22 ppm tended to depress rate of growth at young ages and to prevent or decrease growth and to increase mortality at older ages. Caution should be exercised to avoid salinomycin contamination of turkey diets.

The effects of dietary protein and added fat on carcass characteristics were determined at various ages for female and male turkeys and from three strains: Nicholas Large White (N), Jaindl Large White (JL), and Jaindl Medium White (JM). A total of 1,350 turkeys was divided into 36 pens and fed diets containing 0, 5, or 10% added fat and standard or high protein levels from 8 wk of age to time of processing. One-fourth of the females and one-third of the males from each pen were processed at 16, 20, 24, or 28 wk and at 20, 24, or 28 wk, respectively. Breast meat weight, expressed as a percentage of carcass weight, was greater for JM and JL turkeys than for N turkeys (34.6, 33.9, and 31.7%, respectively), increased with age (31.9, 34.1, and 34.2% at 20, 24, and 28 wk of age, respectively), was greater for females than for males (34.2 and 32.6%, respectively), decreased with added fat (33.7, 33.4, and 33.1% for 0, 5, and 10% fat, respectively) and increased with a 3% addition of dietary protein (33.2 and 33.6%, respectively).

An experiment was conducted to determine the effects of dietary protein and added fat on body weight, feed consumption, and feed efficiency of male and female Nicholas Large White (N), Jaindl Large White (JL), and Jaindl Medium White (JM) turkeys at various ages. At 8 wk of age, 162 males and 288 females from each strain were divided equally into six pens of males and six pens of females per strain. Each of 6 pelleted diets containing standard or high protein and 0, 5, or 10% added fat was fed to one pen of each sex and strain of turkeys. At 20 wk of age, N, JL, and JM males weighed 14.77, 11.56, and 9.00 kg, respectively, and females weighed 8.97, 7.49, and 5.75 kg, respectively. At 28 wk of age, N, JL, and JM males weighed 18.32, 15.10, and 11.65 kg, respectively, and females weighed 10.35, 9.12, and 7.04 kg, respectively. The feeding of diets containing 10% rather than 0% added fat from 8 to 20 wk of age decreased feed consumption 11.1 and 13.1% and increased feed efficiency 16.3 and 16.4% in males and females, respectively. Feeding high protein diets significantly increased body weight gains. The apparent smaller increase than previously experienced in feed efficiency from dietary added fat may be associated with the use of pelleted feed in this experiment.

Two 12-day experiments were conducted with Large White turkeys to determine which amino acids are deficient in a diet containing dehulled soybean meal as the sole source of protein. A 22% protein basal diet composed of 43.3% glucose monohydrate, 45.4% dehulled soybean meal, .5% DL-methionine, 6% stabilized fat, and added minerals and vitamins served as the negative control. Two positive control diets were formed by substituting either 16.5% dehulled soybean meal or a mixture containing amounts of essential amino acids equivalent to those in the added dehulled soybean meal in place of an equal amount of glucose monohydrate in the basal diet. Nine additional diets were formed by removing one or more amino acids from the mixture. Each of the 12 diets in a block design was fed to two pens of males and two pens of females with 8 birds per pen from 7 to 19 days of age in each experiment. Average body weight gain of poults fed the 22% protein diet with added amino acids approached that of poults fed the 30% protein diet (288 vs. 300 g, respectively). Removal of the amino acid mixture from the 22% protein diet depressed body weight gain by 19.0%. Depressions of 19, 16, 11, 7, and 6% in body weight gains resulted from the removal of valine, threonine, lysine, phenylalanine (or tyrosine or glycine), and isoleucine, respectively. A decrease of 5% was required for significance (P less than or equal to .05). When evaluated by this deletion technique, effects of valine and threonine deficiency were more pronounced than effects of lysine deficiency in dehulled soybean meal for young turkeys.