bluuebunny/crossref_metadata_2025 huggingface dataset:
DIGESTION IN THE RUMEN AND AMINO ACID SUPPLY TO THE DUODENUM OF SHEEP FED ENSILED AND FRESH ALFALFA
Authors: FLORES D. A. , PHILLIP L. E. , VEIRA D. M. , IVAN M.
Published: March 2010

A study was conducted with six sheep equipped with rumen and duodenal re-entrant cannulae to investigate differences in duodenal amino acid supply with fresh and ensiled alfalfa. The experiment was conducted as a cross-over design with two 12-d periods consisting of an adaptation phase (5 d) followed by feces collection (5 d), and finally on day 12, 24 h continuous collection of duodenal digesta and sampling of rumen fluid. During the experiment the sheep were restricted on feed to 52 g DM d−1 kg−0.75. Analyses of the forages revealed extensive breakdown of threonine, lysine and other basic amino acids, and high degree of preservation of branched chain amino acids. Relative to the amount consumed, there was a net loss of amino acids at the duodenum with fresh alfalfa but a net gain with silage. The relationship between intake of individual essential amino acids and duodenal recovery was inconsistent. Duodenal recovery of total essential amino acids was 28% higher with fresh than with ensiled alfalfa, a difference which was most pronounced with threonine and lysine. Digestion of organic matter and fiber was unaffected (P > 0.05) by ensiling of alfalfa. Estimates of ruminal pH were higher (P < 0.05) for silage than fresh forage (6.9 vs. 6.7) but VFA concentrations were lower (P < 0.05) for silage (52.1 vs. 64.1 mmol L−1). Rumen ammonia levels were similar for the two forages. The deficit in duodenal supply of essential amino acids with silage is discussed in relation to the problem of silage intake in ruminants. Key words: Alfalfa silage, duodenal amino acids, sheep, rumen digestion
SELECTION PREFERENCE OF STARTER PIGS FED CANOLA MEAL AND SOYBEAN MEAL SUPPLEMENTED DIETS
Authors: BAIDOO S. K. , McINTOSH M. K. , AHERNE F. X.
Published: March 2010

Selection preferences of starter pigs (4–5 wk old) fed diets supplemented with soybean meal (SBM) and canola meal (CM) with or without added flavor were studied in four experiments. In exp. 1, starter pigs were offered a choice between a SBM control diet and one of four isonitrogenous, isoenergetic CM supplemented diets containing either 5, 10, 15 or 20% CM. From 5 to 9 wk of age, pigs consumed two and one-half to seven times more SBM control diet than diets containing 5–20% CM, respectively. In exp. 2, the influence of supplementary monosodium glutamate (0.15%), dextrose (10%) and corn oil (4 and 5%) on the consumption of diets in which CM replaced 50–100% of the protein supplied by SBM was studied. No significant differences in feed intake or pig performance were attributed to the addition of these additives to the CM diets. In experiments three and four, the effect of flavor additives (Pig Krave and Hy Sugr ADE) on the palatability of CM supplemented diets was determined. In exp. 3, feed intake of pigs fed diets containing 100% CM with added flavors was significantly greater than that of pigs fed the 100% CM nonflavored diets. In exp. 4, a single stimulus trial, pigs consumed more (P < 0.001) of the flavored CM diets than the nonflavored diets. The improved feed intake of flavored CM supplemented diets decreased as the level of dietary CM increased. Key words: Palatability, flavor additives, starter pigs, canola meal, soybean meal
CANOLA MEAL AS A PROTEIN SUPPLEMENT FOR 6 TO 20 KILOGRAM PIGS
Authors: McINTOSH M. K. , BAIDOO S. K. , AHERNE F. X. , BOWLAND J. P.
Published: March 2010

Two experiments were conducted to evaluate the replacement value of canola meal (CM) for soybean meal (SBM) in isoenergetic isonitrogenous diets for young pigs between 6 and 20 kg liveweight. Diets utilized wheat, barley, oat groats and blended animal fat as energy sources and evaluated CM at levels from 0 to 100% replacement of SBM. Regression analyses of the results of both experiments indicated that for every 1% addition of CM in the diet, there was a corresponding decrease in average daily feed intake (ADF) and average daily gain (ADG) of 4 and 2 g, respectively. Digestibility coefficients of dry matter and nitrogen were not significantly affected by the level of CM in the diet. Key words: Starter pig, canola meal, soybean meal, protein supplement
EFFECT OF PROPYLENE GLYCOL ON FEED DIGESTIBILITY AND THE GROWTH AND PHYSIOLOGICAL RESPONSE OF RAINBOW TROUT
Authors: HILTON J. W. , ATKINSON J. L. , SLINGER S. J.
Published: March 2010

The effect of supplementing from 0 to 10% propylene glycol (replacing corn starch on an equal weight basis) to a low-energy trout diet on the feed digestibility and the growth and physiological response of rainbow trout was determined. Propylene glycol had no significant effect on the growth, feed:gain ratio, final carcass composition and feed digestibility coefficients of the trout. However, propylene glycol was apparently unstable and/or volatile during feed processing and storage which may have confounded a clear interpretation of the digestibility and growth studies. The trout reared on the 10% propylene glycol supplemented diet also had a slower feeding response than the other groups which may ultimately affect the growth of the trout. It was concluded that propylene glycol was not a cost effective source of dietary energy to the trout and a level of 10% in the diet appeared to be tolerated by the trout. Key words: Trout, propylene glycol, energy, feed utilization, digestibility
RESPONSE TO INJECTABLE SELENIUM AND VITAMIN E ON REPRODUCTIVE PERFORMANCE OF SOWS RECEIVING A STANDARD COMMERCIAL DIET
Authors: CHAVEZ E. R. , PATTON K. L.
Published: March 2010

Thirty-one purebred Landrace sows were allocated to one of three experimental groups to determine the nutritional significance of parenteral injection of 3 mg selenium (Se) plus 408 IU of vitamin E as d-alpha-tocopherol. The three treatment groups consisted of (1) a control (no injection); (2) supplementation at 30, 60 and 100 d of gestation; and (3) supplementation at weaning of previous litter or approximately 1 wk prior to artificial insemination (AI) and at 30, 60 and 100 d of gestation. All sows were fed 2.5 kg d−1 (0.1 ppm Se and 15 IU vitamin E kg−1 diet) during gestation and ad libitum during a lactation period of 3 wk. Treatment did not affect (P > 0.05) weight changes of sows. The blood Se and vitamin A levels were not affected by treatment. Plasma glutathione peroxidase (GSH-Px) activity was kept within a narrow range except at 100 d of gestation when activity was significantly different for treatment 2 versus the control. Vitamin E levels of plasma were significantly (P < 0.05) lower for the control at 60 and 100 d gestation. The Se, vitamin A and vitamin E content of colostrum and milk were not affected by treatment except for treatment 2 having a higher colostrum Se level than the control. In all treatment groups the Se content was significantly greater in the colostrum than in the milk. Litter size, total litter weight at birth and litter size at weaning were significantly greater (P < 0.05) when Se and vitamin E were supplemented. Although overall litter weight at weaning was not significantly different, litters from parity groups 2 of treatments 2 and 3 were significantly heavier at weaning than the control litters. Mortality was lower (P < 0.05) for the supplemented treatments at birth versus the control (1.7% and 3.8% vs. 9.6%). No significant difference was observed from birth to weaning (20.0% and 17.4% and 15.3%). Although the Se, vitamin A and vitamin E contents of the blood from piglets were not significantly different among treatments, GSH-Px activity in the plasma from piglets in the control group was significantly lower (P < 0.05) than from piglets from sows receiving treatment 3. Key words: Selenium, vitamin E, supplementation, sows, reproductive performance
INFLUENCE OF PRELAY AND EARLY-LAY DIETARY CALCIUM CONCENTRATION ON PERFORMANCE AND BONE INTEGRITY OF LEGHORN PULLETS
Authors: LEESON S. , SUMMERS J. D. , JULIAN R. J.
Published: March 2010

Two trials were conducted to note the pullets' response to diet concentrations of calcium from 0.9 to 3.5% fed from 19 wk to day of producing their 4th egg. After this time all birds were fed a common 3.5% Ca layer diet. In Trials 1 and 2 each diet treatment (0.9, 1.5, 2.0, 2.5, 3.0 or 3.5% Ca) was tested with 5 and 16 individually caged birds, respectively. Results from Trial 1 indicated a small (P > 0.05) increase in calcium retention in response to increased diet calcium. Diet calcium concentration had no effect on age at 1st egg, although use of 3.5% Ca during this time resulted in a reduction (P < 0.01) in egg size. This egg size effect was not seen in Trial 2 (P > 0.05). Low calcium diets (0.9–1.5%) had a deleterious effect on early eggshell quality, although after the 4th egg, when all birds were fed a common 3.5% layer diet, all birds exhibited comparable shell quality. In Trial 1, birds sampled after producing their 15th egg exhibited no treatment effect on bone histology, bone ash content or kidney histology. It is concluded that low (0.9–1.5%) calcium diets fed around the time of 1st egg are detrimental to early shell quality. Use of 2.0–3.5% Ca up to time of 4th egg had no consistent deleterious effect on production. Key words: Calcium, pullet, bone histology
EFFECT OF ALTERING THE SOURCE OF NONESSENTIAL NITROGEN ON PERFORMANCE AND CARCASS COMPOSITION OF THE BROILER CHICK
Authors: BEDFORD M. R. , SUMMERS J. D.
Published: March 2010

Male broilers were fed diets containing 14, 18 or 22% crude protein (CP) and 10.88, 12.13 or 13.39 MJ kg−1 metabolizable energy (ME) to 3 wk of age. For each level of CP and ME, three diets were formulated so that excess nitrogen arose mainly from nonessential amino acids (NEAA), essential amino acids (EAA) or both. The source of nitrogen excess had no effect on any of the parameters measured in birds fed the 18 and 22% CP diets. However, at 14% CP and over all energy levels, excess nitrogen in the form of EAA gave rise to superior results with regard to weight gain, feed conversion efficiency and carcass protein when compared to those diets where the excess nitrogen arose mainly from NEAA sources. Increasing dietary energy reduced the effect that source of nonessential nitrogen had on weight gain, feed conversion efficiency and carcass protein deposition at 14% CP. Key words: Amino acids, energy, protein, broilers
FERMENTED WHEY PROTEIN CONCENTRATE FED TO WEANED PIGLETS
Authors: CINQ-MARS DANY , BRISSON G. J. , BÉLANGER G. , LACHANCE B.
Published: March 2010

A 6-wk feeding trial was conducted with whey protein concentrate (WPC) to compare its feeding value when unfermented (U), fermented (F) or fermented and neutralized whey protein concentrate (FN) when added to diets of piglets weaned at 3–4 wk of age. The different WPC were incorporated at the rate of 33.9%, on a dry matter basis, in isonitrogenous and isocaloric corn-soybean meal diets. The 84 crossbred piglets used in this trial were penned on slatted floors, in groups of four, and fed the diets as slurries twice daily. Piglets fed U and F grew faster than piglets fed FN. They also had higher dry matter intake, less diarrhea and tended to have better feed to gain ratios. The amount of sodium hydroxide needed for the neutralization of FN might have been responsible for the lower performance observed with this product. Although piglets fed F had looser feces than those fed U, little difference, if any, in growth or other performance parameters was observed between the two groups. Mortality rate was 11% for piglets fed FN, 7% for those fed F, but was nil for piglets fed U; necroscopied piglets had colibacillosis. Results indicated no advantage for weaned piglets of reducing the lactose level of whey protein concentrate by fermentation following ultrafiltration. Key words: Piglets, whey protein, fermentation, growth, diarrhea
VALIDATION OF TECHNIQUES USED IN PREDICTING CONSTANT FINISH ENDPOINT TRAITS FROM BEEF PERFORMANCE TEST INFORMATION
Authors: McMORRIS M. R. , WILTON J. W.
Published: March 2010

Independent data sets were used to develop and validate prediction equations for weight at market finish (WM), days to market finish (DM) and feed intake to market finish (FM). Use of information currently collected at most bull test stations allowed accurate prediction of WM, DM and, to a lesser extent, FM. Regression coefficients were similar across the data sets used. Correlations of 0.89, 0.76 and 0.81, respectively, were found between predicted and actual values of WM, DM and FM. Key words: Beef cattle, constant finish, performance test information
FETAL PLASMA PROTEIN TURNOVER AND MATERNAL NUTRITIONAL STATUS
Authors: SCHAEFR A. L. , KRISHNAMURTI C. R.
Published: March 2010

In order to determine the effects of maternal nutrient restriction on fetal plasma protein synthesis fetal lambs at 115–125 d of gestation were infused with either 3H or 14C tyrosine for a period of 8 h. From serial blood samples, total plasma proteins were isolated and analyzed for specific activity of protein-bound tyrosine from which protein fractional synthetic rates and half-lives were calculated. Starving the ewes for 48 h reduced the fetal plasma protein fractional synthetic rate by 70% and increased the plasma protein half life approximately threefold. Key words: Fetal plasma protein turnover, maternal nutrition
DISPOSITION OF HAIR MINERALS AT FOUR DIFFERENT BODY SITES OF HEREFORD COWS
Authors: NARASIMHALU P. , MCRAE K. B. , QUINTON D.
Published: March 2010

Hair sampled from the forehead, neck, shoulder and flank regions of 42 pregnant Hereford cows at the starting and 115 d into the dry lot feeding during winter were cleaned, dried and determined for the concentrations of nitrogen, phosphorous, calcium, magnesium, copper, zinc and iron. Hair nitrogen content was similar at all body sites. The unpigmented hair from the head was lower in all minerals, compared with pigmented hair from the remaining body sites (P < 0.05). The neck and shoulder may be the best single site for taking hair samples to monitor the overall mineral concentrations in Hereford cows. Key words: Macrominerals, microminerals, hair pigmentation, beef cow
BIOAVAILABILITY OF COPPER IN PIG FECES
Authors: IZQUIERDO O. A. , BAKER D. H.
Published: March 2010

A chick growth assay was conducted to determine the bioavailability of copper in pig feces. Feces were collected from young pigs fed a 650 mg Cu kg−1 diet. After drying, they were fed to chicks to provide graded intakes of copper. Graded levels of CuSO4∙5H2O were also fed, and the increase in liver copper concentration was compared between the two sources. Dietary addition of 500 mg Cu kg−1 diet as CuSO4∙5H2O depressed chick growth and increased liver copper concentration 42-fold. Addition of 748 mg Cu kg−1 diet as dried pig feces had no effect on growth and increased liver Cu concentration only threefold. These data suggest that the Cu in pig feces is poorly available. Relative to oral CuSO4 providing 250 mg Cu kg−1 diet, orally ingested fecal Cu exhibits a bioavailability no greater than 35.6%. Key words: Swine, chickens, inorganic copper, fecal copper, copper bioavailability
THE ACCUMULATIVE EFFECT OF FINNSHEEP BREEDING IN CROSSBREEDING SCHEMES: WOOL PRODUCTION AND FLEECE CHARACTERISTICS
Authors: FAHMY MOHAMED H.
Published: March 2010

Wool fibers grown on 2 cm2 of skin were removed from the shoulder region of 273 female yearlings born at La Pocatiere Experimental Farm over a period of 3 yr. The yearlings represented nine genetic groups, Finnsheep, DLS (a population of 1/2 Dorset, 1/4 Leicester, 1/4 Suffolk) and seven combinations ranging from 1/8 to 7/8 Finnsheep breeding. The traits studied were staple length, fiber density, clean wool percentage, fiber length and thickness and their variability. Grease fleece weight (GFW) was recorded at first shearing on the 273 yearlings and on an additional 90 female yearlings. GFW was subsequently recorded at yearly intervals up to the 5th shearing. GFW of Finnsheep (F) was 2.3 kg for yearlings and averaged 2.0 kg for older ewes compared to 2.3 and 2.8 kg for the DLS, respectively. The crosses showed positive deviations from the expected means of their parental breeds, the highest was expressed in the [Formula: see text] and 5/8F crosses, GFW exceeded in many crosses that of the better parental breed. The relationship between GFW and the proportion of Finnsheep in the genetic group was linear in second shearing and curvilinear for later shearings. Significant linear relations were also observed in fiber thickness and variability in both fiber length and fiber thickness, whereas significant curvilinear relations were observed in clean wool percentage and fiber length. Compared to DLS, Finnsheep had a higher fiber density (1950 vs. 1551 cm−2), fibers were longer (19.1 vs. 15.8 cm) more variable in length (SD = 4.66 vs. 2.96 cm), finer (20.5 vs. 25.5 μm, and uniform in fiber thickness (SD = 4.8 vs. 5.9 μm), these differences being statistically significant. Most of the crosses exhibited positive heterosis particularly in clean wool percentage, staple and fiber length. The highest heterosis was often manifested in the [Formula: see text] cross. Key words: Wool production, fleece characteristics, crossbreeding, heterosis, Finnsheep, DLS sheep
CORPUS LUTEUM ACTIVITY AND PROSTAGLANDIN LEVELS AFTER PARTURITION IN COWS WITH RETAINED FETAL MEMBRANES
Authors: MATTON PIERRE , ADELAKOUN VICTOR , DUFOUR JACQUES
Published: March 2010

Previous results have shown that progesterone levels were higher on the day of parturition in cows with retained fetal membranes (RFM) than in cows with normal calving, suggesting incomplete lysis of the corpus luteum (CL). This experiment was performed to evaluate the activity of the CL and the level of 13,14-dihydro-15-keto prostaglandin F2α (PGFM) in RFM cows. Cows with RFM or those calving normally (NC) were ovariectomized 12–14 h after parturition. Blood samples were taken from the caudal and utero-ovarian veins. Slices of CL were incubated with or without human chorionic gonadotrophin (hCG) medium for 3 h. Plasma progesterone was higher in both the caudal and utero-ovarian veins of RFM cows than in those of NC cows (1.12 ± 0.25 vs. 0.62 ± 0.08 ng mL−1 and 2.4 ± 0.3 vs. 1.44 ± 0.33 ng mL−1, respectively). PGFM was also significantly higher in RFM cows (3.62 ± 0.19 vs. 2.55 ± 0.15 ng mL−1). Progesterone production by CL slices from both types of cows, incubated without hCG, was similar (65 ± 4.2 vs. 73 ± 5.1 μg g−1); with hCG, however, the progesterone production by the CL of RFM cows was 186.3 ± 10.7 μg g−1, 75.7 μg g−1 more than in CL of cows with normal calving. These results support the hypothesis of an incomplete luteolysis of the CL in RFM cows in spite of hieher levels of PGF2α. Key words: Corpus luteum activity, progesterone, prostaglandin, postpartum cows, retained placenta
EVALUATION OF BULL FERTILITY IN MULTIPLE-SIRE MATING AT PASTURE
Authors: MAKARECHIAN M. , FARID A. , BERG R. T.
Published: March 2010

Pregnancy rates and calving dates of beef cows in four multiple-sire breeding herds in 1980 and 1981 were used to evaluate bull fertility. The bulls were from Hereford, Beef Synthetic and Dairy Synthetic breed groups, and were measured for scrotal circumference, scored for libido and evaluated for semen characteristics 1 wk before the commencement of breeding. Three yearling bulls were assigned to approximately 70 cows in each of the four herds (a total of 12 bulls) during a 60-d breeding season. The progeny of each sire were identified by blood typing. There was one bull in each breeding herd which sired at least 50% of the calves. The average age was higher in bulls with the maximum fertility (P < 0.05) than those with the minimum fertility within each herd. The bulls with minimum fertility within each herd tended (P = 0.08) to lose more weight during the period between yearling and breeding man those with higher fertility. Age of bull and percent normal spermatozoa were the only traits which were associated (P < 0.05) with bull fertility when data were pooled over the herds. Scrotal circumference, sperm volume, preweaning average daily gain, weaning weight and daily gain in the period between yearling and breeding showed positive but insignificant correlation with bull fertility. The measures of libido did not show any association with fertility. Key words: Cattle (beef), bull fertility, multiple-sire mating
EFFECTS OF BARLEY VOLUME-WEIGHT AND PROCESSING METHOD ON FEEDLOT PERFORMANCE OF FINISHING STEERS
Authors: GRIMSON R. E. , STILBORN R. P. , WEISENBURGER R. D. , BASARAB J. A.
Published: March 2010

Barley of three different volume-weights (VW) (light, 47.8; medium, 55.6; heavy, 66.6 kg hL−1) was subjected to two processing treatments (DR, dry rolled; SF, steam flaked) and fed to 192 yearling steers (avg. body weight 332 kg) at a level of 85% of the dietary dry matter (DM) in combination with barley silage (10.75% of DM) and mineral-vitamin premix (4.25% of DM) during the finishing period. No significant two- and three-way interactions were observed for any of the traits studied. Average daily gain (ADG) of cattle fed SF and DR diets was similar (P > 0.05) except during the first 27 d of the trial in which the SF steers gained 9.4% faster (P < 0.05) than the DR steers. Dry matter intake (DMI) of steers fed SF barley tended to be higher (P < 0.10) in period one and in period three than for those fed DR barley but was similar for both processing groups in periods two and four and overall. Dry matter consumed per unit of liveweight gain (DM/G) was similar for the two processing treatments during all periods and overall although it tended (P < 0.10) to be lower for the DR steers during period two. Volume-weight had no effect (P > 0.05) on ADG or DMI. Overall, DM/G decreased (P < 0.01) an average 1.2% for each unit (kg hL−1 increase in VW from 47.8 to 55.6 kg hL−1. DM/G was similar for cattle fed medium and heavy barley. Large steers (avg. bodyweight 350 kg) gained 17.5% faster (P < 0.01), consumed 12% more (P < 0.01) dry matter and required 4.9% less (P < 0.01) DM per unit of gain than small steers (avg. bodyweight 314 kg). Steam flaking of the barley produced carcasses with 0.14 cm more (P < 0.05) grade fat and resulted in 31% fewer (P < 0.05) liver condemnations due to abscesses than dry rolling but did not influence the other carcass quality perameters. Medium VW barley resulted in lower (P < 0.05) grade fat than either light or heavy barley, which produced similar grade fat measurements. Large steers, marketed at an average liveweight that was 14.5 kg heavier (P < 0.01) than the small steers, had lower (P < 0.05) marbling scores than the small steers. Key words: Barley, volume-weight, steers, processing, dry rolling, steam flaking
PREPARATION OF PROTEASE FROM MIXED RUMEN MICROORGANISMS AND ITS USE FOR THE IN VITRO DETERMINATION OF THE DEGRADABILITY OF TRUE PROTEIN IN FEEDSTUFFS
Authors: MAHADEVAN S. , SAUER F. D. , ERFLE J. D.
Published: March 2010

Mixed rumen microorganisms present in bovine rumen fluid were extracted with butanol-acetone to provide a dry powder which retained 75–80% of the proteolytic activity of strained rumen fluid (SRF). Sixty percent of the proteolytic activity of the powder was extracted with water and concentrated on an Amicon XM-300 filter to give a protease preparation which had about 30% of the activity present in the SRF. The protease preparation was used for the determination of the rates of feed protein degradation in vitro by incubating at pH 6.8 in 0.1 M potassium phosphate buffer and measuring the rate of amino acid (and ammonia) production by the ninhydrin method. The relative degradation rates of the true proteins from feedstuffs tested were: soybean meal > fish meal > linseed meal and blood meal > canola meal > corn gluten meal. Substituting Streptomyces griseus protease for the rumen protease gave results which were very different from those obtained with the rumen enzyme. The advantages of using the rumen protease over other in vitro methods and the practical applicability of the procedure are discussed. Key words: Rumen, protease, preparation, in vitro, feed protein degradability
THE INFLUENCE OF MOLYBDENUM AND SULFUR ON VARIOUS COPPER PARAMETERS OF AFAUNATED RAM LAMBS OF DIFFERENT SIRE BREEDS
Authors: ROBINSON J. A. , DEVLIN T. J. , WITTENBERG K. M. , STANGER N. E.
Published: March 2010

Thirty-two afaunated ram lambs, sired by Dorset, Suffolk or Line M rams, were used in a randomized complete block experiment with repeated measures to study the effect of sire breed and dietary supplemental molybdenum ((NH4)6 Mo7O24°4H2O) and sulfur (Na2SO4) on selected criteria of copper (Cu) status. Criteria used included whole blood, plasma and liver Cu concentrations and plasma ceruloplasmin oxidase (CpOx) activity. The basal diet (64.2% crushed barley, 29.6% chopped alfalfa-brome hay) contained 7.7 mg Cu, 1.4 mg molybdenum (Mo) and 2.4 g sulfur (S) kg−1 dry matter (DM). Basal diet was fed to control lambs (Diet I). Mo and S were added to the premix such that diets fed to lambs assigned to Diets II, III and IV provided 1.4, 6.6 and 11.0 mg Mo kg−1 DM, and 3.8, 4.0 and 3.8 g S kg−1 DM, respectively. Dietary Cu concentrations fed to lambs in Diets II, III and IV were 7.4, 7.4 and 8.0 mg kg−1 DM, respectively. The diets were pelleted and fed free-choice with the alfalfa-brome hay for 105 d. Tap water was available to the animals at all times. Blood samples were taken by jugular venipuncture and liver samples by biopsy every 35 d. Total Cu was determined by atomic absorption spectrophotometry following wet ashing of the sample. Oxidase activity of a Cu-containing enzyme, CpOx, was also measured in plasma. Blood and plasma Cu were reduced (P < 0.01) in Diet III only. Liver Cu and CpOx activity were reduced (P < 0.05) in all supplemented groups. Diet IV had high blood and plasma Cu (> 15.7 μM L−1) when liver Cu (< 50 μg g−1 wet basis) and CpOx activity (< 40 ΔA min−1 L−1) were low, characteristic of conditioned Cu deficiency. The effect of S alone was inconclusive due to a 10-d contamination of Diet II with 28.3 mg Mo kg−1 DM. Diet by sire breed interaction, significant (P < 0.05) only with blood and plasma Cu data, suggests a genetic influence on Cu metabolism. Key words: Sheep, lambs, copper, sulfur, molybdenum, afaunation
NUTRITIONAL PERFORMANCE AND INTESTINAL ABSORPTIVE CAPACITIES OF NEONATAL LAMBS FED MILK REPLACER OR DAM'S MILK, WITH OR WITHOUT ACCESS TO CREEP FEED
Authors: MIR P. S. , MIR Z. , SHANER A. D. , SORENSEN B. L.
Published: March 2010

Thirty-two, week old lambs, averaging 6.3 kg were used in a 5-wk feeding trial, in a 2 × 2 factorial experiment where lambs were maintained on either milk replacer or their dam's milk with or without access to creep feed. The xylose absorption test was conducted on three randomly selected lambs from each of the four treatments during the 3rd week of the experiment, and on termination of the experiment these were sacrificed by exsanguination. Sections of the duodenum, proximal jejunum and mid-jejunum were collected within 10 min of slaughter to determine: (1) xylose and galactose transfer into everted sacs in 90 min of incubation, (2) lactase activity and (3) villus height and crypt depth. Over the 5-wk trial, dam fed lambs gained more weight (440 and 380 g d−1) (P < 0.05) than lambs receiving milk replacer (276 and 244 g d−1). Lambs fed milk replacer and having access to creep feed gained the least (157 g d−1) during the first 3 wk of the experiment. This detrimental effect of creep feed on weight gain of lambs fed milk replacer was eliminated by the end of the 5th week. Plasma xylose concentrations at 2 h after xylose administration were greater for lambs fed milk replacer only than for dam fed lambs (53–24 mg dL−1 plasma). Lactase activity was greater in the proximal jejunum and lower in the duodenum and mid-jejunum. Villus height was greater in jejunal sections than in duodenal sections. Dietary treatments were found to affect nutritional performance of the lambs and villus morphology only. Key words: Milk replacer, dam's milk, everted sacs, lactase, villus height, intestinal absorption, lamb
EFFECTS OF AMMONIATION OF CANOLA SEED CONTAMINATED WITH WILD MUSTARD SEED ON GROWTH, FEED UTILIZATION AND CARCASS CHARACTERISTICS OF PIGS
Authors: BELL J. M. , KEITH M. O. , DARROCH C. S. , McGREGOR D. I.
Published: March 2010

Ammoniation (NH3) of canola seed (CS) containing wild mustard seed (WMS) present as a contaminant resulted in reduction of CS glucosinolates but not of WMS hydroxybenzyl glucosinolate or lysine contents. Feeding diets containing 25% CS including 0, 3, 6 and 9% WMS to crossbred barrows from 23 to 57 kg had no effects on average daily gain (ADG) or daily feed intake (FI) but feed:gain ratio (FG) was poorer. Serum triiodothyronine (T3) was unaffected but thyroxine (T4) was depressed by WMS, a result of hydroxybenzyl glucosinolate intake. FI was improved by NH3. This was attributed to reduced concentrations of sinapine and glucosinolates in CS and WMS. Barrows fed from 57 to 100 kg liveweight showed no effect of dietary level of WMS on ADG or FG but 7.2 and 10.8% WMS resulted in leaner carcasses than with 0% WMS. Use of 30% CS in the diet, regardless of WMS level, resulted in fatty acid changes in backfat compared with the control diets. Fatty acids C14, C16, C16:1 and C18 were reduced and C18:1, C18:2 and C18:3 were increased by consuming diets containing 10–12% oil from CS and WMS. Gilts (57–100 kg) fed diets containing 0.2 and 10.5% WMS in CS fed at 30% of the diet had similar ADG but gilts fed the high WMS diet produced leaner carcasses. Key words: Canola seed, wild mustard, pigs, feeding, glucosinolates, fatty acids
EFFECT OF DIETARY CATION-ANION BALANCE AND CALCIUM CONTENT ON GENERAL PERFORMANCE AND INCIDENCE OF LEG ABNORMALITIES OF BROILER CHICKENS
Authors: HULAN H. W. , McRAE K. B. , PROUDFOOT F. G. , SIMONS P. C. M. , SCHAGEN P. J. W. VAN
Published: March 2010

A factorial experiment with 1440 day-old Hubbard chicks was conducted to assess the interacting effects of dietary Na, K, Cl and Ca on general performance and incidence of leg abnormalities, especially tibial dyschondroplasia (TD). For Ca at 0.95%, all combinations of Na (0.17, 0.30), K (0.80, 1.10, 1.40), Cl (0.22, 0.44) were present; for Ca at 1.38% the combinations were the same except for K (0.80, 1.40). The various cation combinations produced 12 and 8 different meq kg−1 of (Na + K − Cl) for Ca at 0.95 and 1.38%, respectively. Body weight gain and feed conversion were affected by the main effects K, Ca and Na and also by their interaction. Both weight gain and efficiency of feed utilization were influenced by cation-anion balance as shown by significant Ca × K, Na × K, Ca × Na (feed conversion only) and K × Cl interactions. Increasing dietary K or Na increased litter moisture, whereas Cl moderated the effect of Ca. The incidence of TD was reduced by increasing dietary Ca, Na or K but their effects are interdependent on each other and on the level of dietary Cl as evidenced by significant Ca × Na, Na × K and Na × K × Cl interactions. Feeding diets with (Na + K − Cl) between 155 and 300 meq kg−1 had little effect on growth and feed conversion. Dietary Ca level changed both the pattern and response of birds for growth and feed utilization, suggesting that the term meq kg−1 (Na + K − Cl) is an inadequate measure of dietary cation-anion balance. Key words: Dietary cation-anion, calcium, leg abnormalities, broilers
THE EFFECT OF FASTING ON LEUCINE DEGRADATION IN CHICK SKELETAL MUSCLE
Authors: WU G. , THOMPSON J. R.
Published: March 2010

In vitro degradation of leucine in intact extensor digitorum communis muscles from fed and from 12- and 24-h-fasted 10-day-old broiler chicks was investigated. The net rate of leucine transamination and the rates of oxidative decarboxylation, oxidation of carbons 2–6 and total CO2 production from 14C-labelled leucine increased (P < 0.01) from 0.57 ± 0.03, 0.42 ± 0.02, 0.95 ± 0.07 and 1.37 ± 0.09 nmol h−1 mg muscle−1 for the fed group to 0.79 ± 0.05, 0.60 ± 0.04, 1.34 ± 0.04 and 1.94 ± 0.10 nmole h−1 mg muscle−1, respectively, following 24 h fasting. The values for the same rates following 12 h fasting were 0.60 ± 0.02, 0.44 ± 0.02, 1.04 ± 0.05 and 1.47 ± 0.06 nmol h−1 mg muscle−1, respectively, and were significantly (P < 0.01) less than the values obtained following the 24 h fast. The values obtained for the rates of leucine catabolism in muscles from the 12-h-fasted group did not differ (P > 0.05) from the values obtained in muscles from the fed group. These results demonstrate that the rate of leucine catabolism in the skeletal musculature of the chick is increased during fasting. Increased leucine degradation provides energy for muscle metabolism and constitutes a mechanism whereby chicks are able to adapt to fasting. Key words: Leucine degradation, skeletal muscle, fasting, chicks
THE EFFECTS OF CARCASS GRADE AND SEX ON THE LEAN CONTENT OF BEEF CARCASSES
Authors: JONES S. D. M. , TONG A. K. W. , ROBERTSON W. M.
Published: March 2010

Heifer (n = 82) and steer (n = 89) carcasses were compared for lean content at the same grade (Canada A1 or A2), or at the same depth of average rib fat thickness within a grade (8.5 or 12.1 mm). Lean content for A1 grade carcasses was found to average 63.3% with a range from 55.6 to 69.2%. The corresponding figures for A2 grade carcasses were 60.0% lean and a range from 53.7 to 66.2%. A1 grade steer carcasses were found to contain 1.7% more lean than A1 grade heifer carcasses, but this difference was reduced to 1.2% when the comparison was made at an equal depth of subcutaneous fat thickness. There were no sex differences in lean content for A2 grade carcasses. The results are discussed with reference to lean content variation in existing carcass grades and pricing policies for heifer and steer carcasses of the same carcass grade. Key words: Beef, carcasses, steer, heifer, composition, grade
AN IMPROVED PROCEDURE FOR FECAL COLLECTION IN CALVES
Authors: FROHLICH A. A. , SREEMANNARAYANA O. , MARQUARDT R. R.
Published: March 2010

A fecal collection bag for calves has been modified so that the opening to the bag becomes distended during defecation. This modification greatly reduces spillage and thereby permits virtually complete collection of fecal material. Key words: Calves, fecal collection bag
ACCEPTABILITY OF ALFALFA HAY TREATED WITH AN ORGANIC ACID PRESERVATIVE FOR HORSES
Authors: LAWRENCE L. M. , JASTER E. H. , WISCHOVER L. , MOORE K. J. , HINTZ H. F.
Published: March 2010

Alfalfa hay treated with a commercial preservative containing 80% propionic and 20% acetic acid was evaluated as a feed for horses. In a two-choice preference test, horses preferred untreated hay (P < 0.05). When yearlings were fed either treated or untreated hay for 1 mo, there was no difference in feed consumption or weight gain indicating that when given no choice, horses find hay treated with propionic and acetic acid acceptable. Key words: Alfalfa, organic acid preservative, horse
FAT METABOLISM IN GROWING SWINE: A REVIEW
Authors: FARNWORTH E. R. , KRAMER J. K. G.
Published: March 2010

At birth, piglets have little body fat that can be mobilized. The influx of high-fat milk causes a rapid increase in body fat stores and a depression of lipogenic enzyme activity. Conversely, lipolytic enzyme activity increases after birth. Changing the fat intake of sucking piglets affects the amount of fat deposition. The length of the sucking period also influences body composition at weaning. Weaning produces a pronounced but temporary decrease in total body lipid, despite an increase in fat synthesis. The effect of weaning on lipolysis is not clear due to a lack of experimental data. During the growing period, fat continues to build up even though lipogenic enzyme activity tends to decline with age. The composition of the diet, the sex of the animal and genetic factors have all been shown to influence the rate of lipogenesis. Fewer reports have been published in which factors affecting lipolysis have been studied and the results are often less conclusive. However, the combined activities of lipogenic and lipolytic processes do not account for the large quantity of body fat found in growing pigs. Key words: Swine, fat, lipogenesis, lipolysis, diet, sex.
GENOTYPE × ENVIRONMENT INTERACTIONS FOR POSTWEANING GROWTH PERFORMANCE OF BACKCROSS BULLS
Authors: RAHNEFELD G. W. , McKAY R. M. , FREDEEN H. T. , WEISS G. M. , NEWMAN J. A. , LAWSON J. E.
Published: March 2010

The effects of pretest and genotype × environment (GE) interactions of 137 reciprocal backcross bulls produced under two contrasting environments (Brandon, Manitoba and Manyberries, Alberta) were evaluated for postweaning performance traits. Differences in weaning weight and average daily gain during the pretest periods defined as preweaning (ADGBW), weaning to on-test (ADGWT), and birth to on-test (ADGBT) associated with the fixed effects of station of origin, breed cross and station of origin by test were not significant. Station of test effects were significant (P = 0.0001) for ADGWT and ADGBT. None of the GE interactions involving the station of origin was significant (P > 0.10) for the postweaning growth traits and probabilities exceeded 0.20 for all but three of the 40 traits. The GE interactions involving station of test were nonsignificant (P > 0.20) for all but eight traits. All of these exceptions involved the cumulative average daily gain in the eight periods which excluded the first 14 d of test. Although the GE interaction for average daily gain for 140 d of test was not significant there were substantial breed cross differences in growth rates at the two test locations. Users of performance test results, however, are generally concerned with absolute performance values, not statistically significant differences. Viewed in this context, the differential responses of genotypes under different test environments, even though statistically nonsignificant, could have important implications to the industry. Key words: Cattle, postweaning growth, genotype × environment interaction
A STUDY OF ULTRASONIC PROBING TECHNIQUES FOR SWINE II. PREDICTION OF CARCASS YIELD FROM THE LIVE PIG
Authors: SATHER A. P. , TONG A. K. W. , HARBISON D. S.
Published: March 2010

In order to examine the effect of probe site and pig weight at probing on ultrasonic machine and operator accuracy, 227 pigs were probed for subcutaneous backfat thickness at 80, 90, 100 or 110 kg. Ultasonic probe sites were 5 cm off the midline on the midback at a point aligned with the root (B1) or the apex (B2) of the curve of the last rib. Loin sites were defined as 15 cm posterior to B1 (L1) or directly above the stifle joint of the hind leg (L2) of a pig standing normally. A third midback measurement was defined as for B1 but 6 cm off the midline (B3). The value of layer 2 or total backfat depth measurements at these five sites in predicting carcass dissectible fat and lean tissue content were examined. The best combinations of probe sites included L1 and either B1, with R2 of 0.41, 0.70, 0.72 and 0.78 or B2 with R2 of 0.38, 0.70, 0.71 and 0.76 for 80-, 90-, 100-, and 110-kg pigs, respectively, when total backfat was used to predict percent dissectible fat of carcass. These results indicate that carcass yield cannot be predicted adequately at 80 kg and that the optimum probe weight was between 90 and 100 kg. However, the additional expense associated with performance testing pigs at weights greater than 90 kg cannot presently be justified. The R2 for either B1 + L1 or B2 + L1 when fat depth of layer 2 was measured at 90 kg was 0.66. The greatest consistency between operators was observed when fat depth of layer 2 was measured. Key words: Swine, ultrasonic probe, slaughter weight, carcass yield
SEASONAL VARIATION IN CIRCULATING GONADOTROPIN AND TESTOSTERONE LEVELS AND IN TESTIS SIZE OF YEARLING RAMS DURING AND SUBSEQUENT TO IMMUNONEUTRALIZATION OF ESTRADIOL OR TAMOXIFEN TREATMENT IN THE NONBREEDING SEASON
Authors: SANFORD LEE M.
Published: March 2010

Seasonal variations in endocrine function and testis size with manipulation of the estrogen negative-feedback signal were assessed for yearling rams. Groups of three rams were passively immunized against estradiol-17β (estradiol) or injected with the antiestrogen tamoxifen (30 mg d−1) for 8 wk (July and August). In comparison with a group of four control rams, seasonal changes in many reproductive parameters were different for treated rams (group × period, P < 0.01). Immunized rams had higher mean LH levels at weeks 2 and 8, and higher baseline levels of LH and more frequent releases at week 8. Mean testosterone levels were increased between weeks 4 and 8 to values that were twice those of the breeding season as a consequence of higher baseline levels and larger episodic secretions. This was not associated with enhanced testicular regrowth, although regression in early winter occurred at a faster rate. Estradiol immunoneutralization was also associated with elevated levels of FSH. Tamoxifen had an inhibitory estrogen-like action on the hypothalamic-pituitary axis. Treatment suppressed LH pulsatility consistently and lowered testosterone to near undetectable values during the first 4 wk; this was associated with progressive decreases in testis size which were reversed with cessation of treatment. During the last month of tamoxifen treatment, the magnitude of the LH and FSH responses to exogenous GnRH was reduced. Key words: Estrogen immunization, tamoxifen, testosterone, gonadotropins, testis, ram
THE INFLUENCE OF FEEDING LEVEL DURING LACTATION ON THE OCCURRENCE AND ENDOCRINOLOGY OF THE POSTWEANING ESTRUS IN SOWS
Authors: KIRKWOOD R. N. , BAIDOO S. K. , AHERNE F. X. , SATHER A. P.
Published: March 2010

Two experiments were performed with 78 second parity Lacombe sows to determine the influence of nutrition on reproductive performance. During a lactation of 35 d sows were fed daily either 3 (L) or 6 kg (H) of a diet having 16% crude protein and 12.5 MJ DE kg−1. For exp. 1, six L- and six H-fed sows were given an intravenous injection of gonadotropin releasing hormone (GnRH) at 21 d of lactation and blood was sampled at −30, −10, 0, 10, 20, 30, 45, 90 and 120 min from the time of injection. Prestimulation luteinizing hormone (LH) levels were lower for L-fed than for the H-fed sows (1.34 ± 0.1 vs. 1.93 ± 0.2 ng mL−1' P < 0.02). Peak LH levels achieved after UnKH injection, however, did not differ significantly (5.0 ± 0.6 and 5.8 ± 0.5 ng mL−1 for L and H sows, respectively). In exp. 2, 38 sows were fed the H and 40 fed the L level of feed throughout a 5-wk lactation. As expected, low-level feeding in lactation resulted in a greater body weight and backfat loss (17.4 ± 1.6 vs 41.2 ± 2.3 kg and 3.2 ± 0.4 vs. 6.3 ± 0.1 mm; P < 0.001 for both). Low-level feeding also resulted in an increased incidence of anestrus (15.0 vs. 0.0%) and an extended remating interval (140.7 ± 11.7 vs. 103.4 ± 2.1 h; P < 0.05). At the postweaning estrus, sows were inseminated with either fresh (F) or thawed (T) semen. Treatment groups were thus HF, LF and LT. Pregnancy rate was influenced by both feed level and semen type (90, 72, 69 and 39% for groups HF, HT, LF and LT, respectively). Ovulation rate was unaffected by feed intake (18.7 ± 0.9 vs. 18.2 ± 0.5 for L and H sows, respectively) but embryo survival was influenced by both feed intake and semen type (82.7 ± 2.5, 46.4 ± 9.7, 68.3 ± 9.6 and 53.7 ± 9.8% for groups HF, HT, LF and LT respectively). Eight H and twelve L-fed sows were blood-sampled via indwelling vena caval cannulae at 6-h intervals from weaning until the end of estrus. No treatment effect was noted for plasma levels of LH, growth hormone, estradiol-17β or testosterone during this period. It was concluded that low-plane feeding in lactation and the consequent increased weight and backfat loss reduce reproductive performance of sows. However, the mechanism(s) controlling this effect remain to be fully elucidated. Key words: Sow, lactation, nutrition, estrus
GROWTH AND CARCASS COMPOSITION OF RAM LAMBS TREATED WITH CLONIDINE
Authors: KENNEDY A. D. , BELLUK B. M.
Published: March 2010

Average daily gain (ADG), feed efficiency and carcass composition were studied in ram lambs treated with a continuously administered low or high dose of clonidine. Groups of 10 Suffolk lambs and 10 Strain 2 lambs (a synthetic Finnish Landrace, Suffolk, Shropshire line) were implanted at 28-d intervals with Alzet® osmotic pumps containing either sterile H2O (control), a low dose of clonidine (5–8 μg kg−1 d−1; D) or a fivefold higher dose of clonidine (24–41 μg kg−1 d−1; 5D). The effect of clonidine on average daily gain was dose-, breed- and time-dependent. Growth response was only observed during the latter part of the trial. At this time the effects of both the low and high doses of clonidine were positive in Suffolk lambs whereas in Strain 2 lambs the effects were negative. Clonidine caused a reduction in dressing percent and kidney fat as a percentage of slaughter weight in a dose-related manner with the effect more pronounced in the fatter Strain 2 lambs. Percentage fat in the longissimus dorsi muscle of the 10th–12th rib section of lambs treated with the low dose of clonidine (3.42 ± 0.24) was greater than that of control lambs (2.55 ± 0.24) and lambs treated with the high dose of clonidine (2.52 ± 0.24). Key words: Clonidine, growth, carcass composition, lambs
THE ADDITION OF WHOLE SUNFLOWER SEEDS AND SODIUM BICARBONATE TO FAT DEPRESSING DIETS FOR LACTATING COWS
Authors: WHITE B. G. , INGALLS J. R. , SHARMA H. R.
Published: March 2010

Twelve Holstein cows, 13–15 wk postpartum, were randomly assigned to four treatments in a Lucas Switchback design with 4-wk periods. Experimental diets were control, 1% NaHCO3, 9% whole sunflower seeds (WSS) and 1% NaHCO3 plus 9% WSS. Diets without WSS were balanced with sunflower meal, sunflower oil and wheat straw. The isonitrogenous, isocaloric total mixed concentrate, corn silage and hay diet was fed in a ratio of 65:28:7, respectively, on a dry matter (DM) basis. The long hay was fed separately. Diets were fed ad libitum once a day aiming for a 5% ort. Total DM intake and milk yield were not different (P > 0.05) among treatments. Milk fat percentage and yield were increased (P < 0.05) by inclusion of WSS in the diet. Treatments had no affect (P > 0.05) on levels of milk protein or lactose. Total volatile fatty acids (VFA), molar percentage of individual VFA, and rumen ammonia levels were unaffected by dietary treatments. Molar percentage of short chain fatty acids (SCFA) in milk did not change (P > 0.05) with the inclusion in the diet of NaHCO3 and WSS alone, but when fed in combination there was an increase (P < 0.05) in molar percent of SCFA. Cows consuming WSS had lower levels (P < 0.05) of C18:2 in milk fat than control animals which received the same amount of fat but in a different physical form. Yields of de novo synthesized fatty acids (butyrate to palmitate) during week 4 were increased (P < 0.05) when cows consumed WSS with no treatment effect on yield of octanoic acid. Key words: Dairy cattle, sunflower seed, fat test, fatty acid, bicarbonate