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PubMed1977

["Milk aflatoxin" and transfer of toxicity].

Diet including 20 p. 100 of lyophilised milk produced by Goat who consumes peanut meals containing 1,530, 79 and 54 microng/kg aflatoxins with 1,136, 64 and 54 microng/kg aflatoxin B1, is given to duckling during 23 days. There is no influence of this diet on growth, feed efficiency and liver or kidney histology. In contrast, direct consummation of Peanut meal, with the highest level of aflatoxins, produces 18 p. 100 mortality and characteristic injuries of aflatoxiocsis.

Aflatoxins↗

PubMed1999

The effect of dietary wheat middlings and enzyme supplementation. 1. Late egg production efficiency, egg yields, and egg composition in two strains of Leghorn hens.

A study was conducted to test the effects of wheat middlings (WM) with and without enzyme (xylanase and protease) supplementation on late egg production (EP), egg yields, and egg composition in two strains of Leghorn hens (DeKalb Delta and Hisex White). Six diets were randomly assigned to 300 birds (150 birds per strain) from 42 to 60 wk of age. Diet 1 was a corn-soybean meal control, Diets 2 and 3 had 8 and 16% WM, respectively, Diet 4 had 8% WM with 0.1% enzyme, and Diets 5 and 6 had 16% WM with 0.1 and 0.2% enzyme, respectively. Each dietary treatment was replicated five times per strain. Egg production, feed consumption (FC), feed efficiency (FE), percentage dirty eggs, specific gravity (SP), egg weight (EW), and egg mass (EM) were measured on a weekly basis. Egg components (EC) were measured biweekly and birds were weighed every 4 wk. Egg production was not significantly affected by diet, with averages of 83.7, 85.7, 84.1, 84.2, 82.3, and 84.0% for Diets, 1, 2, 3, 4, 5, and 6, respectively. Strain had a marked effect on FC, with Hisex having higher FC than DeKalb hens. Feed consumption also showed a significant diet by strain effect, being lower for Hisex hens fed diets with enzyme compared to diets without enzyme. DeKalb hens had better FE than Hisex hens, and addition of enzyme to 16% WM improved it further. Strain and diet had a significant effect on EC with higher percentages of albumen and yolk for diets with enzyme and for DeKalb hens. Percentage shell was lower for DeKalb hens than for Hisex hens but was not affected by diet. There was also a significant increase in EW for Diets 4 (63.1 g), 5 (63.8 g), and 6 (63.2 g) compared to Diets 1 (62.1 g), 2 (62.4 g), and 3 (63.0 g), with DeKalb hens showing an increase with Diet 5 compared to Hisex hens. Egg mass improved with the higher rate of enzyme in 16% WM diet compared to the lower enzyme level. Specific gravity declined with enzyme supplementation in WM diets. Eggs from DeKalb hens had lower SP than those from Hisex hens for all diets. Percentage dirty eggs did not differ significantly among treatments but was higher for the Hisex strain than for the DeKalb strain. There were no differences in BW between the two strains of hens or among diets. Adding protease and xylanase to diets rich in fiber can improve the egg output without affecting production parameters.

Animal Husbandry↗

PubMed2004

CB1 cannabinoid receptor knockout in mice leads to leanness, resistance to diet-induced obesity and enhanced leptin sensitivity.

OBJECTIVE: There is growing evidence for an implication of the CB1 receptor subtype of the endocannabinoid system in the regulation of eating and fat deposition. To further define the physiological role of these receptors in the control of energy balance, we characterized the phenotype of CB1 receptor knockout (CB1(-/-)) mice maintained on an obesity-prone regimen or on a standard chow. DESIGN: CB1(-/-) male mice were compared to wild-type animals (CB1(+/+) male mice) in two feeding paradigms: (1) with a standard laboratory regimen (3.5 kcal/g, 14.5% of energy as fat) and (2) on a free-choice paradigm consisting of offering both the standard laboratory chow and a high-fat diet (HFD) (4.9 kcal/g, 49% of energy as fat). RESULTS: When maintained on the standard diet, CB1(-/-) mice are lean. At the age of 20 weeks, their body weight and adiposity are, respectively, 24 and 60% lower than that of CB1(+/+) mice. They are slightly hypophagic, but when expressed as percent of body weight, their relative energy intake is similar to that of the wild-type animals. Furthermore, inactivation of CB1 receptors reduces plasma insulin and leptin levels, and enhances the response to intracerebroventricular leptin injection. The free-choice paradigm shows that the preference for a high-fat highly palatable chow is slightly delayed in onset but maintained in CB1(-/-) mice. However, loading CB1(-/-) mice with this obesity-prone diet does not result in development of obesity. Knockout mice do not display hyperphagia or reduction of their relative energy intake in contrast to CB1(+/+) mice, and their feeding efficiency remains low. These data suggest an improved energetic metabolism with the high-fat regimen. Furthermore, the insulin resistance normally occurring in HFD-fed mice is not present in CB1(-/-) mice. CONCLUSION: These results provide evidence that the stimulation of CB1 receptors is a key component in the development of diet-induced obesity, and that these receptors and their endogenous ligands are implicated not only in feeding control but also in peripheral metabolic regulations. The lack of effect of SR141716, a selective CB1 receptor antagonist, in CB1(-/-) mice further supports this hypothesis, as this compound was previously shown to display potent anti-obesity properties in diet-induced obese C57BL/6 mice.

Animals↗

PubMed1980

Lithium and porcine aggression.

One hundred and forty-eight growing pigs were used in four experiments conducted to determine the effect of lithium (Li) on the level of aggression among newly mixed, previously unacquainted pigs. Pits maintained on low levels of dietary Li (17 to 84 ppm) attained serum Li concentrations of .1 to .7 mEq/liter. At these low serum levels, biting activity was consistently lower than it was among control pigs, although the difference was usually not statistically significant. Low levels of dietary Li did not significantly affect rate of gain or feed efficiency. When high concentrations of serum Li were achieved by an intraperitoneal injection, pig aggression was reduced (P < .05) to almost zero for 10 hr postmixing. This effect was probably due to drug-induced malaise associated with potentially toxic serum Li concentrations (above 3.0 mEq/liter). These data suggest that Li can substantially reduce aggression among pigs that are unfamiliar with each other. However, the resulting emesis and reduced feed intake associated with high levels of serum Li are sufficient to contraindicate its use for reducing fighting among unfamiliar growing pigs.

Aggression↗

PubMed1989

Utilization of dietary diammonium citrate by germ-free chicks.

This study was conducted to clarify the effect of the gut microflora on the utilization of dietary diammonium citrate in the chick. Germ-free and conventional Single Comb White Leghorn chicks were given a basal diet, which contained adequate amounts of all essential amino acids but none of the nonessential amino acids as nitrogen sources, or a diammonium citrate-supplemented diet. Irrespective of presence or absence of the gut microflora, values for body weight gain, feed efficiency, and protein and energy utilization were improved by supplementing the basal diet with diammonium citrate. This suggests that the gut microflora are not required for the chick to utilize diammonium citrate.

Amino Acids↗

PubMed1991

The early presence of food-oriented appetitive behavior in developing rats.

The appetitive behavior of 3- to 6-day-old rat pups was studied by testing their ability to direct their ingestive behavior to a restricted food source. We found that, from 3 days of age, pups were able to feed efficiently from such a source. More specifically, pups that were deprived of nutrition but not of maternal care as well as pups that were dehydrated ingested significantly more than nondeprived animals, and did so whether liquid diet was spread over the entire floor surface beneath them or restricted to a fraction of the floor surface. However, pups that had been nutritionally and maternally deprived were not able to direct their feeding. The general locomotor activation of pups in this latter group appeared to interfere with their ability to direct their behavior to the restricted source. These results indicate that from early ages, developing rats possess the appetitive competence to guide their behavior and suggest that previous findings of poorly directed behavior were a confound of the behavioral activation shown by pups tested in a state of maternal deprivation.

Animals↗

PubMedDate not supplied

Antioxidant defense mechanisms in the female rat: interactions with alcohol, copper, and type of dietary carbohydrate.

The purpose of this study was to examine the effects of ethanol, type of dietary carbohydrate (fructose vs. starch), and levels of dietary copper (deficient vs. adequate) on antioxidant defense mechanism in the female rat. The consumption of 20% ethanol in the drinking water depressed growth rate due to a reduction of feed efficiency. Ethanol also lowered hepatic copper concentration, but had no effect on hepatic iron. Among the three antioxidant enzymes studied [i.e., superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase], only catalase activity was increased by ethanol. This effect was independent of copper or the type of dietary carbohydrate. As expected, copper deficiency dramatically reduced SOD. Copper deficiency also reduced GSH-Px activity; however, the combination of fructose feeding with copper deficiency caused a further reduction in GSH-Px. The data show that copper deficiency, per se, and the combination of copper deficiency with fructose feeding lower the antioxidant defense system in female rats.

Alcohol Drinking↗

PubMed2006

The effect of dietary protein level and total sulfur amino acid:lysine ratio on egg production parameters and egg yield in Hy-Line W-98 hens.

A 3 x 3 treatment arrangement varying in dietary protein and TSAA:Lys was used to evaluate the effect of low-protein diets fed to Hy-Line W-98 laying hens. Phase I was 20 to 43 wk of age with 18.9, 17.0, and 14.4 g of protein/hen per day and 0.97, 0.85, and 0.82 TSAA:Lys, whereas phase II was 44 to 63 wk of age with 16.3, 14.6, and 13.8 g of protein/hen per day and 0.92, 0.82, and 0.72 TSAA:Lys. Egg production and feed consumption decreased from 83.7 to 82.2% and 98.8 to 95.6 g, respectively. Feed efficiency improved from 1.680 to 1.645 g of feed/g of egg mass with decreasing dietary protein. Body weight gain was similar for hens fed high or medium protein diets. In phase II, hens consuming 13.8 g of protein/day had significantly reduced egg weight compared with hens consuming 14.6 or 16.3 g of protein/day. Wet and dry albumen percentage, albumen solids, and albumen and yolk protein percentages were significantly decreased with feeding low-protein diets. Yolk protein percentage was increased from 14.85 to 15.11% when decreasing the ratio from 0.97 to 0.82. Hens consuming a low-protein diet produced eggs with the lowest specific gravity. An interaction was observed for protein retention during phase I, feeding 14.4 g of protein/day or a ratio of 0.97 improved protein retention by 9 and 16%, respectively. Overall, hens consuming 16.3 or 14.6 g of protein/hen per day performed similar to hens consuming 18.9 and 17.0 g of protein/hen per day during P1 and P2, respectively. Also, hens consuming diets containing 0.97 and 0.92 TSAA:Lys produced eggs with improved shell quality as compared with other ratios during P1 and P2, respectively.

Amino Acids, Sulfur↗

PubMed1987

Growth and carcass characteristics of cull cows after different times-on-feed.

Cull cows (N = 48) of similar age from Angus and Hereford breed types were assigned to one of four feeding periods (0, 28, 56 or 84 d) and subdivided into two groups, one implanted with Synovex-H and a non-implanted control. Cows were fed a high energy diet and slaughtered at the end of each feeding period. Average daily gain and feed efficiency were evaluated on each animal during the trial. The following carcass traits were evaluated: USDA yield and quality grade characteristics, boning yield, muscle weights, bone weights, pH and Warner-Bratzler shear force of the longissimus muscle. The left side of each carcass was boned and proximate analysis was determined. No significant implant effects were encountered for any of the traits evaluated; therefore, data were pooled and evaluated by feeding period only. Carcass weight and boneless forequarter and hindquarter tissue weights increased significantly between each feeding period; percent kidney, pelvic and heart fat (KPH) and yield grade did not differ (P greater than .05) until d 56 and 84, respectively. Quality grade and marbling scores improved (P less than .05) between 28 and 56 d of feeding. Biceps femoris weight changed during the 84-d experiment from 4.1 kg on d 0 to 5.3 kg on d 84 (P less than .05). Proximate analysis of the boneless tissue indicated an increase (P less than .05) in extractable fat of approximately 6% for each feeding period (6.3% fat on d 0 to 25.4% on d 84).(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Nutritional Physiological Phenomena↗

PubMed1984

Performance, behavior, plasma corticosterone, and economic returns of laying hens in several management alternatives.

Production, physiological, and behavioral data were collected simultaneously on commercial hens housed for 10 months of lay in housing alternatives of cages, deep litter floor pens, and outside range pens. Treatments consisted of housing 1, 2, or 3 hens in small cages 3, 4, 5, or 6 hens in large cages, floor pens housing 51 hens each at three densities, and range pens with 50 hens at .74 m2 (8 ft2) per hen. Egg production rates were greater for all caged hen treatments than for any floor or range groups. Egg numbers favored 2 hens per cage, but economic benefits favored 5 hens per cage. Viability was highest for 1 hen per cage and range pen groups. Feed efficiency was poorer in floor and range groups; however, body weight was generally greater for caged hens. Plasma corticosterone levels did not differ among any cage or range groups, but floor pen hens had significantly elevated levels. Behavioral data for walking and object pecking showed clear differences between cage and floor management alternatives. Preening, standing, and drinking activities were different between some treatments but not clearly different between management alternatives. Feeding activity did not differ among any groups. Although correlations between stress and well-being have not been well elucidated, the sum of the stressors of cage confinement appeared to be less than those from floor pens. Therefore, it was concluded that the well-being of hens in cages was equal to or better than that for free ranging hens or those in floor pens.

Animal Husbandry↗

PubMed1987

Influence of different phosphorus phase-feeding programs and dietary calcium level on performance and body phosphorus of laying hens.

Two nonphytate P (NPP) feeding programs (.35, -.25, -.15% NPP or .45, -.35, -.25% NPP during the age intervals of 23 to 35, 35 to 51, and 51 to 71 wk, respectively) were evaluated for White Leghorn hens in a complete factorial arrangement with 3.3 or 4.0% dietary Ca. Total P (TP) concentrations of the NPP feeding programs, as determined by analysis, were .60, -.48, and -.37 or .70, -.58, and -.46%, respectively. Egg production, feed efficiency, and egg weight over the 48-wk experiment were reduced significantly by the .35, -.25, and -.15% NPP program, irrespective of dietary Ca. Most adverse effects of the low NPP program occurred from 51 to 71 wk when hens fed .15% NPP consumed about 150 mg NPP daily as compared with NPP intake of 250 mg daily for hens fed .25% NPP. Hens fed 3.3% Ca consumed significantly more feed than did those fed 4.0% Ca, irrespective of NPP feeding program or age period. Neither NPP or Ca levels affected eggshell thickness at 71 wk nor mortality during the experiment. Dietary NPP and Ca did not significantly affect P content of the body, including feathers. Body P declined from an average of 8.6 g/hen at 23 wk of age to 7.3 g/hen at 55 and 63 wk. By 71 wk, body P returned to 8.6 g/hen. The results show that NPP intakes of 250 mg and 150 mg/hen daily from 35 to 51 and from 51 to 71 wk, respectively, were inadequate for laying hens' performance, but no adverse effects of these NPP intakes on body P were detected. It seems that utilization of dietary P was affected adversely by high ambient temperatures.

Animals↗

PubMed1987

Urea cycle metabolism: effects of supplemental ornithine or citrulline on performance, tissue amino acid concentrations and enzymatic activity in young pigs fed arginine-deficient diets.

Two experiments were conducted with young pigs to determine the efficacy of ornithine (Orn) or citrulline (Cit) as precursors of arginine (Arg). In Exp. 1, pigs were individually fed an Arg-deficient, semipurified diet (.18% Arg) supplemented with .3% Arg or an equimolar quantity of Orn or Cit. Supplemental Arg or Cit increased rate and efficiency of weight gain, but Orn addition was without effect. Free Arg in plasma 3 h post-prandial was increased by addition of either Arg or Cit to the basal diet. Liver Arg was elevated by dietary addition of Arg, Orn or Cit; kidney Arg and Orn were elevated only in pigs receiving supplemental Cit. Arginine or Cit addition to the diet increased Arg concentration in muscle tissue, but muscle Orn was unresponsive to any of the supplements fed. In Exp. 2, pigs were again fed the Arg-deficient, semipurified diet supplemented with .3% Arg or four times an isomolar quantity of ornithine. Arginine addition to the diet increased weight gain and feed efficiency, while Orn supplementation was without effect. Plasma Orn was increased by excess Orn, while plasma Cit was unaffected by supplemental Arg or Orn. Moreover, excess Orn increased free Orn and proline (Pro) in liver, kidney and muscle. Free Cit, however, increased only in liver from feeding excess Orn. In addition, excess Orn decreased both plasma ammonia and free glutamine (Gln) concentration in brain. Arginase activity was roughly 10, 40 and 100 times greater in hepatic tissue than in renal cortex, renal medulla or intestinal mucosa, respectively, while hepatic ornithine transcarbamoylase (OTC) activity was about 15 times greater than the activity present in mucosa tissue. Renal OTC activity was too low to be accurately measured.

Animals↗

PubMed2001

Effect of congeneric chemical signals of different ages on foraging response and food choice in the field by golden spiny mice (Acomys russatus).

The common spiny mice Acomys dimidiatus and golden spiny mice Acomys russatus coexist in the extreme warm and dry parts of the Rift Valley in Israel. However, they are temporally segregated in that the former is nocturnal, whereas the latter is diurnal. Daily rhythms of physiological and behavioral variables in A. russatus responded to semiochemical signals released by A. dimidiatus (in the urine and feces). Both species feed upon the same food items but at different times of the 24-hr cycle. The main aim of the present study was to test under field conditions the foraging response of A. russatus to odors of different ages released by A. dimidiatus. Various feeding and behavioral variables were compared in three groups of A. russatus. The results show that fresh semiochemical signals released by A. dimidiatus decrease the feeding efficiency and increase the rate of smelling from a distance in A. russatus. These results support the idea that temporal segregation between the two coexisting species is at least partly through semiochemicals present in the urine and feces.

Animals↗

PubMed1996

The role of feed protein quality in reducing environmental pollution by lowering nitrogen excretion. III. Strategies of feeding: a review.

To meet the requirements of pigs a better supply of amino acids can be achieved by using ileal digestibility data of feed ingredients in least-cost feed formulation. Digestibility of amino acids can be improved by addition of multienzyme products, antimicrobial additives and probiotics. Protein accretion may be positively influenced by beta-adrenergic agonists. An adequate ratio of protein to dietary energy is essential to achieve optimal protein utilization. Nitrogen output can be minimized by improving feed efficiency and by eliminating antinutritional substances with adequate processing. The use of the ideal protein concept helps to minimize nitrogen excretion. Management and animal hygiene also have a significant impact on the overall nitrogen balance in animal production.

Adrenergic beta-Agonists↗

PubMed2001

Schooling affects the feeding success of Australian salmon (Arripis trutta) when preying on mysid swarms (Paramesopodopsis rufa).

When feeding on mysid swarms (Paramesopodopsis rufa), juvenile Australian salmon (Arripis trutta) had higher rates of successful attacks when foraging in a group of six fish (55% total advances) than when foraging alone (39% total advances). Six schooling fish had lower approach rates than solitary fish (25% and 37% of total advances, respectively). This result indicated that schooling fish were better at reducing the confusion effect of swarming prey, resulting in more efficient feeding. In larger areas, schools achieved higher rates of successful attacks (19 prey/fish in the large tank, compared with 11 prey/fish in the smaller tank). There was no influence on the feeding success of individual fish when changes were made to the number of prey presented to each fish. Nearest neighbour distances were smallest in the absence of prey, and increased with the introduction of prey and again in an attack sequence. Six fish schooled more cohesively than three fish, indicating increased benefits of schooling in larger groups that contribute to advanced vigilance and foraging techniques.

Journal Article↗

PubMed2003

Influence of dietary ss-glucan on growth performance, lymphocyte proliferation, specific immune response and haptoglobin plasma concentrations in pigs.

Immunomodulatory feed additives might offer alternatives to anti-microbial growth promoters in swine production. The present study was conducted to assess the effects of beta-1,3/1,6 glucans, i.e. of specific yeast cell wall components, on immune function and growth performance in pigs. After weaning at 4 weeks of age, 75 piglets were allocated to 3 different groups for 4 weeks, the diet was supplemented with 0, 0.015 or 0.03% of beta-glucan, respectively. All animals were vaccinated against porcine reproductive and respiratory syndrome (PRRS). After 4 weeks, average daily gains (ADG) of beta-glucan treated pigs were not different from the controls. Feed intake was tendentiously (p < 0.1) increased at 0.03%beta-glucan, without alteration of feed efficiency. Serum haptoglobin concentrations at the end of the 4 week treatment were increased in all groups when compared to the initial levels (p < 0.001), without differences between the groups (p > 0.05). Haptoglobin levels were inversely related to ADG. Lymphocyte proliferation indices were not different in control and treatment groups. Specific vaccination responses, as quantified by the PRRS antibody titres occurred in all animals, but no relation with beta-glucan feeding was observed. Our results indicate marginal benefits of beta-glucan supplements for growth performance and no effect on the immune parameters tested. The observed trend towards increased feed intake needs further elucidation.

Animals↗

PubMed1999

Effect of hen age on intestinal development and glucose tolerance of the Pekin duckling.

Two experiments were conducted to determine whether hen age affects intestinal development and glucose clearance in Pekin ducklings after hatching. In Experiment 1, 85- to 92-g eggs were collected from 32- and 44-wk-old hens. The eggs from older hens contained proportionately more yolk, which resulted in a greater mass transfer of yolk sac DM and lipid from 21 to 25 d of incubation, and ducklings from older hens were heavier at hatching (P < or = 0.0001). Although the ducklings from the older hens were heavier at hatch, BW, feed consumption, and feed efficiency were not significantly different from 7 to 35 d of age. During the first wk after hatching, the age of the hen had no consistent effect on duodenum or lower small intestinal measurements (weight, length, or density). Hen age did not significantly affect plasma glucose concentrations at 0, 30, or 60 min post-injection of glucose (2.5 mg per g BW) in 3- or 6-d-old feed-deprived ducklings. In a second experiment, 85- to 90-g eggs were collected from 33- and 48-wk-old hens to determine whether differences in hen age caused a differential response to a challenge with a higher glucose dosage at 3 d of age. No differences between hen ages were apparent in plasma glucose concentrations at 0 or 30 min postinjection (3.75 mg glucose/g BW). At 60 min postinjection, however, the ducklings from the younger hens had 100.6 mg/dL greater plasma glucose concentrations than the ducklings from the older hens (P < or = 0.02). The glucose tolerance results suggest that differences in metabolism exist between ducklings from the younger hens, even though measurable BW differences did not exist.

Aging↗

PubMed1977

Breeding record analysis in pig herds and its veterinary applications--1: Development of a program to monitor reproductive efficiency and weaner production.

Analyses of breeding records and herd efficiency factors are important for veterinary surgeons supervising reproductive efficiency and piglet performance in breeding herds. These data include: the number of litters produced per sow per year; the distribution of weaning to service intervals; the number of sows returning to service by 30, 60, 90 and 120 days; the percentage of sows farrowing to first service; the percentage of sows found to be not pregnant; and the percentage of sows aborting. Boar performance data, piglet mortality percentages, piglet growth rates, feed efficiency factors and the percentage of sows culled from the herd are also analysed. A computer program was developed to produce these and other data from simple breeding records.

Animals↗