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PubMed1994

Efficacy of feeding glucosinolate-extracted crambe meal to broiler chicks.

Glucosinolates and their breakdown products (nitriles) have long been implicated as toxic factors when feeding rapeseed (Brassica napus) meals and crambe (Crambe abyssinica) meals to poultry. Accordingly, various methods have been developed to remove these compounds from the meals to enhance their value as feed supplements. Glucosinolates and nitriles were extracted from commercially processed, defatted crambe meal by washing with water or various solvent-water mixtures: 50% isopropanol, 50% acetone, or 50% ethanol. In addition, crambe seed was extruded and extracted in the laboratory with isopropanol or hexane. Water washing of commercially defatted meal proved to be the most effective method of extraction, removing 95% of the glucosinolates and nitriles. Meals were fed to 7-d-old broiler chicks at 10% of the diet for 14 d. Weight gain decreased (P < .05) in most groups; however a greater decrease (P < .01) was observed in birds fed meals with high glucosinolate content. Feed intake also decreased (P < .05) in most groups; consequently, feed efficiencies were similar for all groups. No changes in serum chemistries, triiodothyronine, thyroxine, or tissue lesions were associated with glucosinolate or nitrile intake. A relationship (P < .05, r = .74) was found between weight gain and glucosinolate intake. No correlation was found between feed intake and meal glucosinolate or nitrile concentrations.

Alkenes↗

PubMed1988

Effect of efrotomycin in feed on the quantity, duration, and prevalence of shedding and antibacterial susceptibility of Salmonella typhimurium in experimentally infected swine.

The influence of efrotomycin administered at the rate of 16 mg/kg of feed in 10 Salmonella typhimurium-inoculated pigs was determined by comparing this group with a group of 10 pigs inoculated with S typhimurium that were given nonmedicated feed. Two control groups of 4 noninoculated pigs each, 1 group medicated with efrotomycin at 16 mg/kg of feed, the other nonmedicated, also were evaluated. An inoculum of 1.7 x 10(10) colony-forming-units/pig induced colonization of S typhimurium in all 20 pigs. Evaluation of the quantity of shedding did not reveal a clear or consistent treatment-related increase in S typhimurium counts; mean differences between the nonmedicated and medicated groups never exceeded 1 log unit. On the last day of the study (day 56 of the medication), 8 nonmedicated and 9 medicated pigs were determined to be infected with S typhimurium via enrichment procedures, so there was no difference in duration of shedding, and there were no significant differences in prevalence of shedding between the nonmedicated and medicated groups at any of the sampling times. Of 1,340 S typhimurium colonies isolated from the nonmedicated and medicated groups, 1,330 were susceptible to all 12 antibacterials tested, indicating no treatment-related effect on susceptibility. At necropsy, S typhimurium was not isolated from any liver or spleen specimens, and was isolated from only 2 of 20 lymph nodes. However, S typhimurium was isolated via enrichment from the cecal contents from all 20 pigs. There were no treatment-related differences in feed consumption, weight gain, or feed efficiency. Appreciable differences in the measurements were not found between the efrotomycin-medicated and nonmedicated pigs.

Animal Feed↗

PubMed1978

Monensin for the prevention of coccidiosis in calves.

Young calves (Holstein-Friesian) were inoculated with Eimeria bovis on the 3rd day after the start of 31 days' feeding of a ration containing added monensin in 2 dose levels: 16.5 g or 33 g/metric ton of feed. Monensin-treated calves were free of clinical signs of coccidiosis, but inoculated control calves developed diarrhea and had excessive oocyst discharge on days 19 to 28 after they were inoculated. Weight gains and feed efficiency in monensin-treated calves were equal or superior to those factors in noninoculated control calves for the 31-day period.

Administration, Oral↗

PubMed1985

Dietary energy density and frame size effects on composition of gain in feedlot cattle.

Experiments were conducted to evaluate the effects of dietary energy density or genetic background on protein and fat gain of growing cattle. In Exp. 1, 24 Limousin steers were used in a growing-finishing trial. A 2 X 2 factorial arrangement was used with steers randomly allotted to four treatment combinations and fed the following diets: 80% concentrate, high moisture corn-corn silage diet (HI) or a corn silage diet (LO) during both the growing (GRO) and(or) the finishing (FIN) phases. Body composition for both experiments was determined by a deuterium oxide dilution technique. Empty body weight gains were greater (P less than .05) for HI during GRO, FIN and the total trial. Daily protein gains (DPG) were greater (P less than .05) for HI during GRO and FIN, while cattle receiving HI during at least FIN had the greatest (P less than .05) overall DPG. Daily fat gains (DFG) followed the pattern of DPG, being more rapid (P less than .05) for cattle fed HI during either GRO or FIN. Cattle fed the HI diet also tended to be more energetically efficient. In Exp. 2, large frame (LG) and small frame (SM) cattle were used for the evaluation of frame size effects on protein and fat deposition. Steers were individually fed an 80% concentrate, corn-based diet during the entire trial. Average daily gains and daily dry matter intake (P less than .05, P less than .01) were greater for LG, while feed efficiency was similar for both cattle types. Large cattle had greater (P less than .05) DPG than SM cattle, however, DFG were not different. Small frame steers were energetically more efficient (P less than .05), apparently due to composition of gain difference.

Animal Feed↗

PubMed1994

A critical review of minimal vitamin B6 requirements for growth in various species with a proposed method of calculation.

We conclude that vitamin B6 is efficiently conserved by the tissues and that the major dietary requirement is to meet physiological stresses such as growth, pregnancy, lactation, vigorous exercise, and/or disease. A reasonable approximation of the minimal requirement for growth in most species can be obtained by assuming 15 nmol vitamin B6 for each g gain in body weight. For birds and fish, which can achieve 1 g gain/g feed, the vitamin B6 content would need to be about 15 mumol (3 mg)/kg feed. Such an intake is achievable with a variety of natural diets and would also be adequate for most mammalian species, which have lower feed efficiencies. Although well-balanced natural diets are usually adequate, supplementation with 5-10 mumol (1-2 mg)/kg diet is inexpensive and would provide a safety factor to allow for variations in feed composition and physiological stresses such as pregnancy, disease, parasites, and so on. At this time, whether the metabolic changes associated with increases in vitamin B6 intake above the minimum confer long-term health benefits on the organisms is not clear. Excessive vitamin B6 intake can be toxic. Fish and prawn seem to be particularly sensitive to this toxicity. Additional work is needed to clarify the interactions between vitamin B6 requirements and protein intake.

Animals↗

PubMed1982

Toxicologic studies in growing sheep fed silage corn cultured on municipal sludge-amended acid subsoil.

Field corn was grown on subsoil, pH 5.5, that had been amended with 100 dry tons per acre (224 metric tons per hectare) of municipal sewage sludge from Syracuse, New York. The corn plants containing 3.88 ppm dry weight of cadmium were field-chopped and ensiled, and the silage was fed to growing sheep for 225 d. The sheep fed the sludge-grown corn silage showed a significantly (10 higher feed efficiency, (2) higher hepatic microsomal p-nitroanisole O-demethylase activity, and (3) higher concentrations of cadmium in liver and kidney and nickel in kidney as compared to the control animals. No significant treatment effects were observed in mutagenic responses for animal feed or feces samples. No consistent treatment effects were noted during histopathologic examination of sheep tissues.

Animal Feed↗

PubMed1979

Preliminary investigation on the nutritive value of krill meal in the feed of broiler chickens and laying hens.

Krill meal was used as a protein feed in rations for broiler chickens and laying hens and its nutritional effectiveness was studied in comparison with conventional feed-stuffs of animal origin. In experiments with 650 broiler chickens from 1 to 28 and from 29 to 56 days to fattening krill meal was added to the standard feedmixture in lieu of fish meal, and dried skim-milk, and at higher levels also in lieu of soyabean oilmeal. In the experiment with 22 layer hens kept in individual cages 3% of the fish meal were substituted by 3% of krill meal. The performance of chickens fed on diets with krill meal was lower in comparison with analogical groups fed on fish meal. Higher levels of krill meal, exceeding 15 and 11% in the first and second period of feeding respectively, reduced the weight gains and feed intake of chickens. The fatty acid C14, C18 and C18:1 content of internal body fat was changed in chickens fed on higher levels of krill meal. In the experiment with hens krill meal decreased the feed efficiency, the pigmentation of egg yolks, however, was more intensive and the vitamin A content of yolks was increased in comparison with the control group. The results show that krill meal can be used as a partial substitute of fish meal in the feed of broilers and hens.

Amino Acids↗

PubMed1999

The effect of cyclopiazonic acid on the development of pale, soft, and exudative pork from pigs of defined malignant hyperthermia genotype.

Malignant hyperthermia (MH) and the mycotoxin cyclopiazonic acid (CPA) are each associated with abnormal calcium homeostasis in skeletal muscle, a key underlying factor in the development of pale, soft, and exudative (PSE) pork. To determine whether the natural presence of CPA in livestock feed ingredients contributes to the varying incidence of PSE in the pork industry, various levels of CPA (.1 to 50 mg/kg of diet) were included in the diets of market weight hogs (n = 52) of defined malignant hyperthermia genotype (NN = normal, Nn = a MH carrier, and nn = MH-positive). Animals with two copies of the MH mutation (nn) displayed improved live animal performance compared with NN and Nn animals (increased feed intake, average daily gain, and feed efficiency) but yielded lower quality loin chops as indicated by lower 45-min pH (P<.01), higher Commission Internationale de l'Eclairage (CIE) L* color coordinate values (P<.05), and higher drip losses (P<.01). The effects of CPA varied. In the first feeding trial, conducted under normal outside temperatures (2 degrees C), CPA had no effect (P> .2) on either live animal performance or meat quality. During the second trial, conducted under extreme outside temperatures (-18 degrees C), CPA-dependent reductions (P<.05) in feed intake, average daily gain, and 45-min pH in nn hogs support the possibility of interactions between malignant hyperthermia and dietary CPA on skeletal muscle calcium homeostasis and the development of PSE pork. These results suggest that this interaction may require stressful environmental conditions or the ingestion of CPA doses much higher than occur under natural conditions.

Animal Feed↗

PubMed2002

Pleiotropic effects in Hereford, Limousin, and Piedmontese F2 crossbred calves of genes controlling muscularity including the Piedmontese myostatin allele.

Objectives were to determine 1) effects on traits measured from birth to slaughter in F2 cross calves from sire breeds that differ in potential for lean tissue growth but have similar mature BW and 2) the gene action of the mutant Piedmontese myostatin allele. Hereford (normal muscling, H), Limousin (moderate increase in muscling, L), and Piedmontese (muscular hypertrophy, P) sires (20 to 25 per breed) were bred at random to crossbred cows to produce F1 calves that were inter se-mated within sire breed to produce F2 calves that were grown out, finished, and slaughtered. Piedmontese-cross calves were genotyped for the G-A transition mutation at the myostatin locus characteristic of P (msP). Genotypes were classified on the basis of having zero (P0), one (P1), or two (P2) copies of msP (H, n = 227; L, n = 207; P0, n = 40; P1, n = 107; and P2, n = 37). Limousin-cross F2 calves had heavier birth (but dystocia was not affected) and weaning weights, gained faster, had more muscle, less fat, larger pelvic area, and more efficient feed conversion than Hereford-cross F2 calves. Normal-muscled Piedmontese-cross F2 calves (P0) were similar to Hereford-cross F2 calves except that they required less assistance at birth in heifer dams, had less fat, gained slower, were less efficient, and had larger pelvic area. Addition of msP alleles (P1 and P2) consistently increased muscle through hyperplasia, decreased fat, and increased adjusted efficiency, but many of those changes were not linear. Residual variances for breed were heterogeneous for most traits related to muscularity. This heterogeneity was caused by increased variances for L and P and(or) lower variances for H. Accounting for the msP alleles decreased the variance for P in most traits, but heterogeneity remained for most traits among the five genotypes because L remained high, H was low, and(or) P2 was low. We conclude that differences in muscularity affect most traits, and when differences in muscularity include the msP allele, there is an incremental, but not equal, change in most traits with the addition of each copy of the msP allele. Advantages of L could be captured through normal crossbreeding and selection schemes but with some caution because of potential problems from increased variability. Advantages of P could be best captured through more complex breeding and selection programs that would lessen potential negative impacts and through marketing systems that do not penalize for very low fat.

Alleles↗

PubMed1988

Effect of supplemental potassium in the receiving diet and form of antibiotic on feeder pig performance.

In five separate trials 901 feeder pigs (769 purchased and 132 university-raised) were used to determine the effect of level of dietary K (.64 vs 1.00 vs 1.40%), form of neoterramycin (feed-grade vs water-soluble) and a long-lasting oxytetracycline injection on subsequent performance. Purchased pigs fed a 28-d receiving diet with 1.00% K gained faster (P less than .05) than the control pigs fed a .64% K diet (.64 vs .60 kg) during a 1980 summer trial. Feed efficiency was not affected by level of dietary K. Three additional trials conducted during January, July and October of 1981 failed to substantiate this beneficial effect on rate of gain. Feeder pig performance was not different (P greater than .05) when either feed-grade or water-soluble neoterramycin was used as a 14-d receiving treatment at preventative levels. However, in one trial nearly twice as many pigs on the medicated feed diet required additional treatment for sickness compared with pigs receiving water medication (14.5 vs 7.9%; P less than .1). Giving pigs an injection of a long-lasting oxytetracycline (LA-200) either at the market or upon arrival at the finishing facility had no effect on performance; however, the pigs were home-raised rather than purchased; consequently, their health was excellent.

Animals↗

PubMed1982

Effect of dietary protein and energy on broiler performance and production costs.

Varying levels of dietary protein (16, 20, 24, 28, 32, 36%) and energy (2600, 2800, 3000, 3200, 3400, 3600 kcal [metabolizable energy] ME/kg) were fed in a factorial arrangement to broilers to determine the effect of alteration in nutrient density on performance and economic traits. Body weight and feed efficiency improved with increased dietary protein or energy. However, a significant interaction between protein and energy indicated the importance of a balanced energy: protein ratio to achieve optimum performance. Sex differences in protein requirements were observed for 49-day body weights. Returns over feed costs remained essentially constant, providing a balance between dietary protein and energy was maintained. However, an increase above 28% crude protein or 3400 kcal ME/kg resulted in reduced returns as did excessive quantities of one nutrient relative to the other. Male broilers were able to accommodate a higher level of dietary protein (24%) than female broilers (20%) before returns were reduced. Regression equations were derived for prediction of performance and economic parameters. Reliable estimates were obtained with the inclusion of protein or energy intake in addition to diet composition.

Animal Feed↗

PubMed1984

Relationship between dietary fiber and nutrient density and its effect on energy balance, egg yolk cholesterol and hen performance.

Two experiments were conducted to determine the effect of dietary fiber in rations of varying nutrient density on egg yolk cholesterol, energy balance and reproductive efficiency of laying hens. Initially, four diets arranged in a Latin square design were tested: low, medium and high nutrient density diets and a control diet. The energy-to-protein ratio was 171.8 kcal/% protein for all diets. Significant differences (P less than 0.01) were observed between diets for feed intake, feed efficiency and fecal output of the hens. Dietary differences in yolk cholesterol, egg production, egg weight, body weight change and energy balance were not significant, and hence unrelated to dietary fiber level. A significant negative correlation (P less than 0.01) was found between yolk cholesterol and egg production (r = -0.45) or egg energy output (r = -0.38). In addition, yolk cholesterol was positively correlated with body weight change (r = 0.23, P less than 0.01). In the second experiment, the possible relationship between level of feed intake, body weight change and yolk cholesterol was further investigated. Yolk cholesterol tended to increase when the laying pullets consumed more than 387 kcal ME/day or gained more than 100 g in body weight. When the energy intake was less than 340 kcal ME/day or the birds lost body weight, an increase in yolk cholesterol also was noted but was inversely related to feed intake or body weight change.

Analysis of Variance↗

PubMed1980

Effect of hatcher fogging on hatcher airborne bacteria and broiler performance.

A comparison between fogged and nonfogged hatcher air was undertaken in 4 trials to determine effects on hatcher airborne bacteria, hatch statistics, and broiler performance. Eighteen day incubated eggs were artificially contaminated with a mixed Eschericia coli and Staphylococcus aureus culture when eggs were transferred to hatchers. Fogging with a disinfectant at 12-hr intervals during the hatching period caused significant reductions in total airborne bacteria and S. aureus counts. Counts of E. coli were not significantly affected. Growth data from 150 chicks from each hatcher from each trial showed 50-day feed efficiency and 50-day male body weights were significantly improved in chicks hatched in the fogged hatcher.

Air Microbiology↗

PubMed1988

Effects of ad libitum versus restricted feeding on body composition and egg production of broiler breeders.

A 64-wk experiment was conducted in which the effects of ad libitum vs. restricted feeding were studied during the pullet-layer transition and laying periods. Broiler breeder females were reared through 23 wk of age according to the breeder's recommendation. At 24 wk of age the following four treatments were imposed: T1, fed restricted amounts of feed according to the breeder's management guide; T2, feed restricted from 24 to 32 wk of age (as in T1), then fed ad libitum; T3, fed ad libitum from 24 to 64 wk of age; and T4, fed ad libitum from 24 to 32 wk of age, then restricted to 85% of the average 24 to 32-wk consumption. Birds fed ad libitum during the pullet-layer transition period (T3 + T4) consumed an average of 37 g more feed per day and reached sexual maturity 14 days earlier than restricted birds (T1 + T2). Live body weight, carcass weight, carcass weight corrected to zero fat content, and percentage carcass fat were all significantly higher at first egg in ad libitum vs. restricted birds, but these differences were small. Birds fed ad libitum during lay (T2 + T3) produced more eggs, achieved a higher peak percentage hen-day production, consumed more feed, and contained more body fat at last egg than hens restricted during lay (T1 + T4). However, neither mortality, feed efficiency, egg weight, egg fertility, nor egg specific gravity was affected by treatment.

Animals↗

PubMed2005

Susceptibility of Escherichia coli from growing piglets receiving antimicrobial feed additives.

Concerns regarding an apparent association between the use of antimicrobial feed additives (AFAs) in food animal production and a concomitant increase in antimicrobial drug resistance among zoonotic enteropathogens have provided the impetus to propose cessation of their use. While AFAs have been used in food animal production for nearly 50 years, the future use of AFAs will require an understanding of the effects of different classes of antimicrobials on the antimicrobial resistance of commensal flora. The present study examines the effect of three AFAs (apramycin, carbadox, and chlortetracycline) on the antimicrobial susceptibility of Escherichia coli in growing piglets and on animal performance. Three replicate trials were conducted using growing piglets fed standard diets with and without antimicrobial feed additives (AFAs). Fecal samples were cultured selectively for E. coli at regular intervals from all piglets from birth to market and antimicrobial susceptibility testing of E. coli isolates was performed using a replica-plate screening method and a broth microdilution method. While resistance to tetracycline in E. coli varied widely by sample, group, and trial, a significant increase in the percentage of resistant isolates was observed in piglets receiving AFAs when compared to controls (p < 0.0001). Resistance to apramycin increased in E. coli from piglets fed apramycin when compared to controls (p < 0.0001). However, upon removal of apramycin, resistance in E. coli declined to baseline levels by day 75. Piglets receiving AFAs demonstrated improved feed efficiency during phase 4 (p < 0.001), and higher average daily gains in phases 3 and 4 (p < 0.0001). This study suggests that antimicrobial resistance to AFAs in E. coli is drug-dependent and that some antimicrobials may be suitable for continued use in feeds during specified growth periods without concern for persistence of resistant E. coli populations.

Animal Feed↗

PubMed2005

Adaptive significance of avian beak morphology for ectoparasite control.

The beaks of Darwin's finches and other birds are among the best known examples of adaptive evolution. Beak morphology is usually interpreted in relation to its critical role in feeding. However, the beak also plays an important role in preening, which is the first line of defence against harmful ectoparasites such as feather lice, fleas, bugs, flies, ticks and feather mites. Here, we show a feature of the beak specifically adapted for ectoparasite control. Experimental trimming of the tiny (1-2 mm) maxillary overhang of rock pigeons (Columba livia) had no effect on feeding efficiency, yet triggered a dramatic increase in feather lice and the feather damage they cause. The overhang functions by generating a shearing force against the tip of the lower mandible, which moves forward remarkably quickly during preening, at up to 31 timesper second. This force damages parasite exoskeletons, significantly enhancing the efficiency of preening for parasite control. Overhangs longer than the natural mean of 1.6mm break significantly more often than short overhangs. Hence, stabilizing selection will favour overhangs of intermediate length. The adaptive radiation of beak morphology should be re-assessed with both feeding and preening in mind.

Adaptation, Biological↗

PubMed2006

Differential effects of 4 types of environmental enrichment on aggressive pecking, feather pecking, feather loss, food wastage and productivity in Japanese quail.

1. We examined the effects of 4 types of environmental enrichment (foraging opportunities, structural complexity, sensory stimulation/novelty, and social companionship) on aggressive and feather pecking, feather condition, food wastage, body weight, feed conversion, and egg production in adult Japanese quail. Sex differences were examined where possible. 2. GLM analysis was used to evaluate the effects of enrichment and housing, while test-retest reliability and the stability of measures over 18 d were assessed using partial correlation. 3. Foraging enrichment reduced food wastage. 4. Body weight, feed conversion, and egg production were not affected by enrichment. Rates of aggressive and feather pecking were also not significantly affected, but these behaviours were observed very infrequently in this study. 5. Socially-housed birds had poorer feather condition, lower body weight and less efficient feed conversion than singly-housed birds. Social housing did not affect food wastage. 6. There were not sex differences in feather pecking, feather condition, food wastage, or feed conversion. 7. All measures except feather pecking were reliable over 24 h, but only feather condition and body weight were stable over 18 d. The instability f the behavioural measures over time suggest that enrichment effects may vary with age.

Aggression↗

PubMed1994

The effects of diets formulated on an ideal protein basis on growth performance, carcass characteristics, and thermal balance of finishing gilts housed in a hot, diurnal environment.

Forty-eight finishing gilts (initial BW = 70.6 +/- .95 kg) were randomly assigned to one of eight experimental treatments in a 2 x 2 x 2 factorial arrangement with main effects including dietary lysine (.60 vs 1.00%), source of amino acid fortification (intact protein vs synthetic amino acids formulated on an ideal protein basis), and environmental temperature (thermoneutral [TN]: 20 degrees C vs hot, diurnal [HD]: 27.7 to 35 degrees C). The ideal protein diets were formulated by using corn and soybean meal to meet the fifth-limiting amino acid; synthetic lysine, threonine, tryptophan, methionine, or isoleucine were added to meet the gilts' estimated requirements. The ratios of other total amino acids relative to lysine were as follows: threonine, 66%; tryptophan, 17%; methionine and cystine, 56%; and isoleucine, 63%. Average daily gain, ADFI, and feed efficiency (G/F) were similar for gilts fed the intact and those fed the ideal proteins diets (P > .10). Increasing dietary lysine improved d 0 to 14 ADG (P < .01), but no differences were observed for the overall experiment. Gilts in the HD environment ate less feed and had lower ADG than gilts in the TN environment (P < .01). A temperature x lysine interaction was observed (P < .02) for G/F. Increasing dietary lysine had no effect on G/F of gilts in the TN environment but improved G/F of gilts in the HD environment. Gilts fed the intact protein diets had higher (P < .01) N intake and plasma urea concentrations. Gilts fed the ideal protein diets had lower (P < .05) plasma essential amino acids, with the exception of lysine. Carcass protein and lipid contents were improved (P < .01) for gilts in the HD environment and for those fed 1.00% lysine. Backfat thickness and longissimus muscle area (P < .01) were improved and lipid accretion rate tended to decrease (P < .08) in gilts fed 1.00% lysine. The source of amino acid fortification did not influence carcass characteristics (P > .10). Rectal, skin, and ear temperatures were higher for gilts in the HD environment (P < .05). Metabolic heat production was elevated by feeding gilts the ideal protein diets (P < .03). In conclusion, increased dietary lysine improved G/F and carcass leanness in gilts to a greater extent in HD than in TN environments. However, no improvements in growth performance or carcass traits resulted from feeding ideal protein diets.

Amino Acids↗