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PubMed2002

Utilization of distillers grains from the fermentation of sorghum or corn in diets for finishing beef and lactating dairy cattle.

Beef finishing and dairy lactation experiments were conducted to evaluate the nutritional value of distillers grains (DG) from sorghum or corn fermentation, in both wet (35.4% DM) and dry (92.2% DM) form (dairy trial only). In the finishing experiment, 60 yearling steers were used in a completely randomized design with three diets that were fed for 127 d: 1) control diet with 86% (DM basis) dry-rolled corn and no DG; 2) 30% of ration DM as wet corn DG in place of dry-rolled corn; and 3) 30% of ration DM as wet sorghum DG in place of dry-rolled corn. All diets contained a minimum of 6.8% degradable intake protein and 13.0% CP. Steers fed DG had 10% greater ADG (< 0.01) and 8% greater efficiency of gain (P < 0.01) than steers fed the control diet. Wet corn and sorghum DG resulted in similar ADG and efficiency of gain. Hot carcass weights, fat thickness, and yield grades were greater for steers fed DG than for controls (P < 0.07). Improvements in ADG and feed efficiency observed when DG replaced dry-rolled corn indicated that the NEg content of wet DG is approximately 29% greater than that of dry-rolled corn. In the dairy lactation experiment, 16 lactating Holstein cows (eight multiparous, including four fistulated) were used in a replicated 4 x 4 Latin square design with 4-wk periods. Corn and sorghum DG were fed at 15% of the ration DM in either wet or dry form. Diets were fed as total mixed rations that contained 50% of a 1:1 mixture of alfalfa and corn silages, 24.3% ground corn, and 9.1% soybean meal (DM basis). There was no effect of source or form of DG on DMI, ruminal pH and VFA, or in situ digestion kinetics of NDF from DG. Efficiency of milk production was unaffected by diet. Corn and sorghum DG resulted in relatively similar performance when fed to beef or dairy cattle in this study.

Animal Feed↗

PubMed1988

Identification of children with cerebral palsy unable to maintain a normal nutritional state.

7 children aged 2-16 with severe cerebral palsy and growth failure were compared with children of the same weight in respect of their eating efficiency. Children with cerebral palsy took 2-12 times longer to chew and swallow a standard amount of puréed food and 1-15 times longer for solid food than did their weight-controls. A behaviour score of feeding characteristics was higher in children with cerebral palsy than in controls. Even long meal times do not compensate for the severity of these childrens' feeding impairment. The measurements of feeding efficiency provides the basis for early identification of children who cannot be adequately nourished without ancillary feeding by nasogastric tube or by enterostomy.

Adolescent↗

PubMed2004

An evaluation of endo-beta-D-mannanase (Hemicell) effects on broiler performance and energy use in diets varying in beta-mannan content.

Two experiments were conducted to evaluate the effects of a commercial endo-beta-D-mannanase (Hemicell) on overall performance, MEn, net energy for gain, and some serum parameters of broilers fed diets varying in beta-mannan level (experiment 1) and to evaluate effects of enzyme level on the same variables in broilers fed diet high in beta-mannan (experiment 2). As a semipurified beta-mannan source, guar gum was used to alter the dietary beta-mannan level. In experiment 1, guar gum was added at 0, 0.5, 1, and 2% in a corn-soy-based starter diet with (0.05%) and without endo-beta-D-mannanase supplementation in a 4 x 2 factorial design. Enzyme supplementation improved (P < 0.01) feed efficiency at control and each guar gum inclusion level, whereas 2% guar gum supplementation reduced (P < 0.01) BW and increased (P < 0.01) 14-d feed:gain ratio. Enzyme supplementation also increased dietary MEn and net energy gain. In experiment 2, endo-beta-D-mannanase was added at 0, 0.5, 1, and 1.5% in a corn-soy-based starter diet containing 1% guar gum. Increasing endo-beta-D-mannanase supplementation did not affect (P > 0.10) final BW but improved 14-d feed:gain ratio at all inclusion levels. As in the first experiment, ME improved (P < 0.05) with increasing enzyme inclusion. Dietary endo-beta-D-mannanase inclusion significantly reduced water:feed ratio and total dry fecal output (P < 0.01). Taken together, the results of these 2 experiments indicate that endo-beta-D-mannanase supplementation may improve the utilization of nutrients in diets containing beta-mannan.

Animal Feed↗

PubMed2003

Effect of irradiation of individual feed ingredients and the complete diet on nursery pig performance.

A total of 1,210 nursery pigs was used in two experiments to evaluate the effects of irradiation of typical nursery diet ingredients, specialty protein products, and the whole diet on nursery pig performance. In Exp. 1, 880 barrows and gilts (15 +/- 2 d of age at weaning) were used in two growth trials (14 d and 12 d for Trials 1 and 2, respectively) to determine the effects of individual ingredient and whole-diet irradiation on nursery pig performance. Overall (d 0 to 14 of Trial 1 and d 0 to 12 of Trial 2), ADG was greater (P < 0.05) for pigs fed irradiated animal plasma compared with pigs fed the control, the diet containing irradiated microingredients, and the diet that was manufactured and irradiated. Also, pigs fed irradiated soybean meal had greater (P < 0.05) ADFI compared with pigs fed the manufactured diet that was irradiated. Pigs fed the diet containing irradiated animal plasma had improved feed efficiency (G:F; P < 0.05) compared with those fed the diet with irradiated microingredients and when all ingredients were irradiated before manufacturing of complete feed. Finally, pigs fed irradiated corn, whey, fishmeal, soybean oil, microingredients, or if all ingredients or the whole diet were irradiated, had similar ADG, ADFI, and G:F (P > 0.12) to control pigs. In Exp. 2, 330 nursery pigs (20 +/- 2 d of age at weaning) were used to determine the effects of irradiation of commercially available specialty protein products in diets for nursery pigs. Overall, ADG was greater (P < 0.05) when pigs were fed diets containing nonirradiated spray-dried animal plasma and egg combination (SDAPE) and dried porcine digest (DPD) compared with pigs fed the control diet containing no specialty protein products. In addition, G:F was improved (P < 0.05) when pigs were fed diets containing nonirradiated SDAPE, DPD, spray-dried beef muscle (SDBM), and spray-dried whole egg (SDWE) compared with pigs fed the control diet. Pigs fed irradiated SDAPE and SDBM had greater (P < 0.05) ADG than pigs fed the nonirradiated forms. Pigs fed irradiated SDBM had improved (P < 0.05) G:F compared with pigs fed the nonirradiated form. In Exp. 1 and 2, an irradiation treatment level of 8.5 kGy was effective in reducing the total bacterial concentration of all ingredients evaluated, as well as the whole diet in Exp.1. Irradiation of certain ingredients, but not the complete diet, increased growth performance of nursery pigs.

Animal Feed↗

PubMed1983

Effects of excess arginine on swine growth and plasma amino acid levels.

One hundred seventy-six crossbred weaned pigs (4 to 5 wk old) were used in two growth trials to determine the effect of excess arginine on pig growth and plasma amino acid levels. In the first 28-d growth trial, two lysine levels (1.03 and 1.26%) and three arginine levels (.94, 1.29 and 1.63%) were used in a nested treatment arrangement. Lysine supplementation improved daily gains (P less than .05), tended to improve feed efficiency (P less than .12) and caused a general reduction in plasma essential amino acid levels. Arginine had no effect on daily gain or feed intake, but pigs fed 1.03% lysine and 1.63% arginine had reduced gain/feed (P less than .05). Arginine did not affect gain/feed of pigs fed 1.26% lysine. Plasma lysine levels were reduced (P less than .06) by excess arginine in pigs fed 1.26% lysine, but not in pigs fed 1.03% lysine. The four treatments for the second 26-d growth trial consisted of three diets containing .92% lysine and either .72, 1.10 or 1.61% arginine and a positive lysine control (1.10% lysine, .72% arginine). Lysine was the limiting amino acid in the basal diet, but arginine had no effect on daily gain, daily feed intake, gain/feed or plasma lysine levels. Plasma threonine and methionine levels were reduced by excess arginine in both experiments, while the other plasma essential amino acid levels were not affected by dietary arginine. Conclusions are that large excesses of added arginine may affect lysine utilization, but pig performance was affected only when excess arginine was combined with a lysine deficiency. The arginine levels similar to those found in grain-soybean meal swine diets had no effect on pig performance in these experiments.

Amino Acids↗

PubMed1989

Dietary thyrotropin-releasing hormone stimulates growth rate and increases the insulin: glucagon molar ratio of broiler chickens.

The effects of thyroid manipulation on growth, feed efficiency, and plasma hormone levels were determined in rapidly growing chickens. Beginning at 3 weeks of age, eight broiler cockerels were provided with control feed (CF) or feed containing either 1 ppm of triiodothyronine (T3), 1 ppm of thyroxine (T4), 0.3% propylthiouracil (PTU), or 5 ppm of thyrotropin-releasing hormone (TRH) for 3 weeks. Blood samples were taken at 4, 5, and 6 weeks for determination of plasma levels of growth hormone, insulin-like growth factor, T3, T4, insulin, glucagon, glucose, and nonesterified fatty acids. Dietary TRH increased (P less than 0.05) the growth rate of chickens by 14% when compared with the CF group. Plasma growth hormone levels were reduced (P less than 0.05) 65% by dietary T3 and 33% by treatment with either T4 or TRH when compared with the CF group. Plasma insulin-like growth factor levels were 16% lower (P less than 0.05) in PTU-fed birds than the other treatment groups. Plasma T3 levels were elevated (P less than 0.05) 3-fold by dietary T3 and 38% by TRH whereas plasma T3 in the PTU group was 38% below the average of CF birds. Plasma T4 levels were increased (P less than 0.05) by 12-fold in T4-fed birds, decreased 48% in TRH-fed birds, and nondetectable in birds treated with either T3 or PTU. Compared with the other treatments, dietary PTU increased (P less than 0.01) plasma insulin levels 4.3-fold whereas TRH provided a 2.7-fold increase in plasma insulin. Plasma glucagon levels were 26% higher (P less than 0.05) in T3-fed birds than those fed either T4 or PTU. These observations indicate that thyroid activity plays an important role in regulating secretion of GH and the pancreatic hormones. Furthermore, our study demonstrates the potential use of TRH as an orally active growth promoter for poultry.

Aging↗

PubMed2005

Development of a high-efficiency H2 feeder for bioremediation.

An electrochemical dissolved hydrogen feeder equipped with a multi-cathode system and a high-rate recirculation pump was developed in order to examine its feasibility for bioremediation. Results showed that the feeding efficiency was remarkably higher than that in former studies. The reason for the enhanced hydrogen dissolution rate was thought to be due to the large cathode area by applying multiple granular activated carbon electrodes resulting in low current density. Two mass balance equations were formulated and applied to analyze the performance of the apparatus theoretically. The hydrogen dissolution rate calculated from the equations was in fairly good agreement with observed results. It was suggested that the electrochemical H2 feeder would be a competitive alternative as a hydrogen feeding method for bioremediation.

Bacteria↗

PubMed2003

A dose-response study of melengestrol acetate on feedlot performance and carcass characteristics of beef steers.

The dose response of melengestrol acetate (MGA) on ADG (kg/d) and gain efficiency (gain/DMI, g/kg) was estimated in beef steers fed a finishing diet under commercial feedlot conditions. Melengestrol acetate is not approved for use in steers as a feed additive. The study design was five blocks of four pens (each pen was assigned a dose of MGA) with 166 to 200 steers per pen. Melengestrol acetate was fed to steers at 0 (n = 899, five pens), 0.1 (n = 900, five pens), 0.2 (n = 899, five pens), and 0.4 (n = 900, five pens) mg of MGA/steer daily. Pens within a block were slaughtered on the same day. Blocks 1 through 5 were fed MGA for 123, 122, 116, 124, and 138 d, respectively. The experimental unit was a pen of steers, and blocking was based on source of steers. The ADG was 1.81, 1.85, 1.80, and 1.83 kg/d for steers fed 0, 0.1, 0.2, and 0.4 mg MGA per day, respectively. For ADG, the dose was significant, but neither linear nor quadratic effects were significant. Compared with steers of the control group, ADG was greater for steers fed 0.1 mg MGA (P < 0.01). Feed efficiencies were 170, 173, 171, and 172 g/kg for steers fed 0, 0.1, 0.2, and 0.4 mg MGA/d, respectively; however, no effects of dose (P = 0.19) or linear (P = 0.21) or quadratic (P > 0.60) effects were observed. There was no evidence for either positive or negative effects of MGA on DMI, hot carcass weight, dressing percent, quality grade, yield grade, back fat thickness, marbling score, longissimus muscle area, and incidence of dark cutter carcasses in response to feeding MGA to steers at doses of 0.1, 0.2, and 0.4 mg daily. The incidence of buller behavior (0.43 to 1.11%) was low and did not permit an accurate test of the clinical observations that feeding MGA to steers decreases the occurrence of buller steers. Melengestrol acetate fed to finishing beef steers produced small improvements in growth performance (ADG, 2.2%) at the 0.1 mg MGA dose, but none of the doses examined produced improvement in carcass quality or yield grade measurements.

Animals↗

PubMed1996

Dietary effects on fatty acid metabolism of common carp.

The paper summarises experimental data demonstrating effects of various dietary factors exerting changes in the fatty acid composition and fatty acid metabolism of the common carp (Cyprinus carpio L.). Among the dietary factors (1) supplementary feeding in fish ponds, (2) absence of essential fatty acids (EFA) in the diet, (3) starvation, and (4) ration level were studied. It was concluded that supplementary feeding in carp rearing ponds is frequently excessive in the Hungarian carp culture practice, inducing slight EFA-deficiency and enhancing de novo fatty acid synthesis. This latter caused enlarged fat depots with high oleic acid contents in the fish organs and tissues. EFA-deficient diets enhanced the synthesis of oleic acid except when high rate of de novo fatty acid synthesis was suppressed by dietary fatty acids. Feeding EFA-deficient diets caused gradual decrease in the levels of polyunsaturated fatty acids and gradual increase in that of Mead's acid: 20:3(n-9), an indicator of the EFA-deficiency. At prolonged starvation, polyunsaturated fatty acids of the structural lipids were somehow protected and mainly oleic acid was utilised for energy production. At high ration levels, excessive exogenous polyunsaturates were decomposed, and probably converted to oleic acid or energy. Starvation subsequent to the feeding the fish at various ration levels, reflected adaptive changes in the fatty acid metabolism: Below and above the ration level required for the most efficient feed utilisation for growth, decomposition processes of the fatty acid metabolism were accelerated.

Animal Feed↗

PubMed1987

Influence of sarsaponin on growth, feed and nitrogen utilization in growing male rats fed diets with added urea or protein.

Two experiments were conducted with growing male rats to determine the effects of 120 ppm of dietary sarsaponin (S) on nitrogen (N) metabolism when urea or protein are added to the diet. Growth, feed efficiency, N digestibility and balance, urinary N and ammonia-N (NH3-N), and cecal urease and NH3-N were measured. Growth and feed utilization were unaffected by dietary S. Adding urea or protein to the diet increased apparent N digestibility and increased urinary-N excretion. Urea did not affect N balance, whereas growth, feed utilization and N balance were maximized with 22% compared with either 16 or 28% dietary protein. Urinary NH3-N excretion was decreased by S when urea was added to the diet but was not affected when fed with increasing dietary protein. Cecal urease was decreased by S when urea was added or when the protein level was increased in the diet; effects on cecal NH3-N varied between the two experiments. Plasma urea-N was decreased by S. It is concluded that S has minor effects on N metabolism in rats and that NH3-N formation or excretion is only marginally affected by dietary S. If S decreases NH3-N level in confinement facilities, it is concluded that the effect is after the waste material is excreted by the animal, perhaps through reduced urease activity.

Animals↗

PubMed1979

Efficacy of Stenorol (halofuginone). II. Plus roxarsone or bacitracin MD against selected strains of chicken Eimeria.

A total of 879 broiler strain chickens ranging from 2 1/2- to 7 1/2 weeks of age was utilized in four battery experiments to determine whether Roxarsone and/or bacitracin MD added to halofuginone were compatible and beneficial in reducing the effects of coccidial infections. The additives were generally beneficial as measured by weight gain and feed efficiency but not as measured by other parameters such as dropping score, lesion score, or oocyst production. The addition of 200 g of bacitracin/ton of feed did not give an additional response above that from 50 g/ton. Roxarsone in the ration was more effective in younger chickens (2 1/2 week old) than older ones (6 weeks, 2 days and 7 weeks, 3 days).

Animals↗

PubMed1987

Nutritional qualities of stabilized and raw rice bran for chicks.

Rice bran either raw or processed in an extrusion cooker at 130 C was fed to meat strain chickens for 25 days after hatch. Either full fat or hexane-extracted rice bran was placed in the diet at the equivalent of 60% full fat bran. Raw full fat bran for one diet was stored at -23 C until fed, whereas rice bran for all other diets was stored at 32 C. Four experiments were conducted at 6-week intervals. Free fatty acid (FFA) content in oil from raw rice bran stored at the elevated temperature reached 81% by the start of the final experiment whereas FFA in stabilized bran oil remained at about 3%. Chickens fed stabilized rice bran made significantly greater gains than chickens fed raw bran diets. Feed efficiency was superior for chickens fed either full fat or extracted stabilized bran compared with full fat bran stored at either 32 or -23 C. Feed conversion for extracted raw bran was intermediate between stabilized bran and full fat raw bran. Raw bran stored at 32 C (with elevated FFA content) tended to produce lower gains than the frozen raw bran. Analysis of the combined data from all four trials indicated that raw bran held at 32 C produced the lowest gains among all of the diets.

Animal Feed↗

PubMed1990

Tolerance to ground Sesbania macrocarpa seed by broiler chicks and White Leghorn hens.

Two 21-day experiments using day-old male broiler chicks and a 28-day experiment using 35-wk-old White Leghorn hens were conducted to determine the deleterious effects of ground Sesbania macrocarpa seed in the diet. Seed levels of 0, .10, .25, .50, and 1% were used in both experiments, with a 2% level of inclusion added to Experiment 2. The hens were fed diets containing 0, 1, 2, 3, 4, 5, 6, or 7% seed. In each experiment, four replicate pens of 8 chicks or of 5 hens received each treatment diet. In both chick studies, a seed inclusion of 1% caused a significant reduction in body weight at 21 days of age. Total feed intake was significantly lowered by the inclusion of 1% seed in the first study and by 2% seed in the second study. Feed efficiency, excreta moisture, and mortality were not affected by dietary level of seed in either trial. Seed inclusion at 3% or more depressed the daily feed consumption of the hens; at 6% seed inclusion, egg production was reduced. Egg weight, egg specific gravity, mortality, and body weight change were not affected by treatment. Grains containing sufficient S. macrocarpa seed to produce finished feed with 1 or 3% seed would appear to be detrimental to broiler growth and feed intake by hens, respectively. The blending of such grains with uncontaminated stock could be a possible method of utilizing the contaminated grain.

Animal Feed↗

PubMed1984

Interactive effects of dietary calcium, phosphorus and copper on performance and liver stores of pigs.

Three experiments involving 304 pigs were conducted to determine the related effects of copper (Cu), calcium (Ca) and phosphorus (P) on the performance and liver Cu stores of growing-finishing pigs. Rate and efficiency of gain were improved by the addition of 250 ppm of Cu to the diets. Improvements in rate of gain averaged 6.6% (652 vs 696 g/d) to 60.5 kg body weight and 1.7% (713 vs 725 g/d) to 94.5 kg body weight. Feed:gain ratio was improved by 1.4% to 60.5 kg and 1.6% to 94.5 kg body weight when Cu was added to the diet. Increasing the dietary Ca and P levels from .65% Ca and .55% P to 1.2% Ca and .86 or 1.0% P resulted in increased (P less than .01) growth rate to 60 and 95 kg (649 vs 699 g/d and 700 vs 737 g/d, respectively), but feed efficiency was not affected (2.86 vs 2.84 and 3.18 vs 3.17 kg feed/kg gain, respectively.) Feeding the higher Ca and P levels resulted in increased liver Cu levels in pigs fed 250 ppm Cu (189 vs 323 ppm), but Ca and P did not affect liver Cu of pigs fed low Cu diets (29 vs 28 ppm). When dietary Ca and P were varied independently, the high Ca level increased liver Cu, but P had little effect on liver Cu. Increasing the dietary P level partially alleviated the effect of Ca on liver Cu.

Animals↗

PubMed1993

[The influence of oral niacin doses during different dietary protein levels on indexes of rumen fermentation, blood parameters and fattening performance of young bulls].

The influence of added niacin (0, 0.5 or 1 g per animal per day) and different crude protein contents (9.2 to 12.0% of DM) or the supply of various N-sources (urea, rape seed meal, soya bean meal, fish meal) were investigated on rumen fermentation, blood parameters, feed intake, weight gain and dry matter (DM) intake per weight gain in three individual feeding experiments with 156 growing bulls weighing between 175 and 300 kg per animal. Niacin supplementation did not significantly influence (P > 0.05) investigated parameters of rumen fermentation and blood. Ruminal propionate concentration increased insignificantly (from 18.9 to 19.5 moles per 100 moles on the average), inorganic P of blood serum somewhat decreased (from 2.98 to 2.82 mmol per 1) when niacin was added (P > 0.05). Protein level did not significantly influence rumen fermentation and blood parameters except an increased urea concentration in the blood of cattle fed with diets richer in protein. The DM intake of control bulls and niacin supplemented animals amounted to 6.35 and 6.46 kg per animal per day on average. Influence of niacin on DM intake varied in dependence on protein source. The daily weight gain increased from 1003 (control) to 1040 g per animal per day (+ niacin, P > 0.05). Niacin increased weight gain of bulls of urea (+ 43 g) and rape seed or soya bean meal added rations (+ 60 g per animal per day), but did not influence the weight gain in fish meal added rations. Increased weight gain resulted from ruminal and metabolic effects (about 2/3) as well as enhanced feed intake of bulls (about 1/3). Feed efficiency mostly improved.

3-Hydroxybutyric Acid↗

PubMed2002

Feeding broiler chickens wheat and barley diets containing whole, ground and pelleted grain.

The effect of grain form (whole, mash, or pelleted) on the live performance of broiler chickens was determined. In the first trial, six regimens compared the feeding of whole wheat: 1) 0% of diet for the whole trial (0 to 48 d); 2) 5% at 6 d, 20% at 13 d, 35% at 27 d; 3) 5% at 6 d, 35% at 13 d, 50% at 27 d; 4) 5% at 0 d, 20% at 6 d, 35% at 13 d, 50% at 27 d; 5) 5% at 6 d, 50% at 13 d, 65% at 27 d; and 6) 5% at 0 d, 20% at 6 d, 50% at 13 d, 65% at 27d. Each feeding regimen was replicated with steam-pelleted and mash supplements. None of the feed was diluted. The second trial was similar, except that whole barley was fed instead of whole wheat. Feeding mash supplements slowed growth at all ages and lowered mortality caused by sudden death syndrome and ascites plus right heart failure. Cumulative feed:gain was increased by feeding mash supplements in Trial 1. Total weight gain was unaffected by feeding whole wheat but was decreased by most levels of whole barley. Whole-grain diets increased cumulative feed:gain. Feeding whole wheat decreased skeletal problems. Whole-grain diets increased gizzard size but did not alter carcass yield. Feeding whole-grain and mash supplements caused at least a temporary loss in growth rate and feed efficiency but in some cases improved bird health.

Animal Feed↗

PubMed2006

Using simulation models to predict feed intake: phenotypic and genetic relationships between observed and predicted values in cattle.

The objectives of this study were to evaluate the accuracy of the Decision Evaluator for the Cattle Industry (DECI) and the Cornell Value Discovery System (CVDS) in predicting individual DMI and to assess the feasibility of using predicted DMI data in genetic evaluations of cattle. Observed individual animal data on the average daily DMI (OFI), ADG, and carcass measurements were obtained from postweaning records of 504 steers from 52 sires (502 with complete data). The experimental data and daily temperature and wind speed data were used as inputs to predict average daily feed DMI (kg) required (feed required; FR) for maintenance, cold stress, and ADG; maintenance and cold stress; ADG; maintenance and ADG; and maintenance alone, with CVDS (CFRmcg, CFRmc, CFRg, CFRmg, and CFRm, respectively) and DECI (DFRmcg, DFRmc, DFRg, DFRmg, and DFRm, respectively). Genetic parameters were estimated by REML using an animal model with age on test as a covariate and with genotype, age of dam, and year as fixed effects. Regression equations for observed on predicted DMI were OFI = 1.27 (SE = 0.27) + 0.83 (SE = 0.04) x CFRmcg [R2 = 0.44, residual SD (s(y.x)) = 0.669 kg/d] and OFI = 1.32 (SE = 0.22) + 0.8 (SE = 0.03) x DFRmcg (R2 = 0.53, s(y.x) = 0.612 kg/d). Heritability of OFI was 0.27 +/- 0.12, and heritabilities ranged from 0.33 +/- 0.12 to 0.41 +/- 0.13 for predicted measures of DMI. Phenotypic and genetic correlations between OFI and CFRmcg, CFRmc, CFRg, CFRmg, CFRm, DFRmcg, DFRmc, DFRg, DFRmg, and DFRm were 0.67, 0.73, 0.41, 0.63, 0.78, 0.73, 0.82, 0.45, 0.77, and 0.86 (P < 0.001 for all phenotypic correlations); and 0.95 +/- 0.07, 0.82 +/- 0.13, 0.89 +/- 0.09, 0.95 +/- 0.07, 0.91 +/- 0.09, 0.96 +/- 0.07, 0.89 +/- 0.09, 0.88 +/- 0.09, 0.96 +/- 0.06, and 0.96 +/- 0.07, respectively. Phenotypic and genetic correlations between CFRmcg and DFRmcg, CFRmc and DFRmc, CFRg and DFRg, CFRmg and DFRmg, and CFRm and DFRm were 0.98, 0.94, 0.99, 0.98, and 0.95 (P < 0.001 for all phenotypic correlations), and 0.99 +/- 0.004, 0.98 +/- 0.017, 0.99 +/- 0.004, 0.99 +/- 0.005, and 0.97 +/- 0.021, respectively. The strong genetic relationships between OFI and CFRmcg, CFRmg, DFRmcg, and DFRmg indicate that these predicted measures of DMI may be used in genetic evaluations and that DM requirements for cold stress may not be needed, thus reducing model complexity. However, high genetic correlations for final weight with OFI, CFRmcg, and DFRmcg suggest that the technology needs to be further evaluated in populations with genetic variance in feed efficiency.

Animal Feed↗

PubMed1976

Amino acid supplementation of turkey breeder rations.

Beltsville Small White turkey hens (60) were randomized into four groups of 15 hens each, weighed and placed in individual laying cages. Immediately after lighting to initiate production, they were placed on a practical type turkey breeder diet calculated to contain 18.26% protein, 2893 Cal. M.E./kg., 3.13% Ca, 0.80% available P, 1.04% arginine, 0.86% lysine, 0.50% methionine & cystine and 0.24% tryptophane. Amino acids were added to this diet as follows: (1) none; (2) 0.1% lysine; (3) 0.05% methionine and (4) 0.1% lysine & 0.05% methionine. Lysine (0.1%) had no effect on reproductive performance when added to the basal ration or to the ration containing additional methionine. Methionine addition (0.05%) improved production significantly (P less than or equal to .005), improved feed efficiency, and increased egg size.

Amino Acids↗