bluuebunny/crossref_metadata_2025 huggingface dataset:
GENETIC PARAMETERS OF THE MATERNAL GRANDSIRE CONTRIBUTION TO BEEF CATTLE WEANING WEIGHTS
Authors: CROW G. H. , HOWELL W. E.
Published: March 2010

Genetic aspects of maternal influence on weaning weights in beef cattle were examined using analyses within breed and parity of dam (first, second, third and fourth and greater parities) of Angus, Charolais and Hereford Record of Performance data. A mixed model which included herd-year and maternal grandsire (MGS) was used. The data were adjusted for calf sex within breed and parity of dam prior to analysis. The heritability of dam influence on her offspring weaning weight averaged 0.23 for first parity data of the three breeds. Heritability for second and third parities of the three breeds were lower than this but averaged 0.16 in parity four and greater. MGSs contributed significantly to variation in weaning weights. Their contribution, however, is a composite of both direct and maternal genetic effects. Key words: Beef cattle, weaning weight, maternal, variance components, heritability
HEIFER GROWTH IN SEVERAL STRAINS OF HOLSTEINS AND AYRSHIRES AND IN PROGENY OF AYRSHIRE COWS MATED TO BROW SWISS AND NORWEGIAN RED BULLS
Authors: LEE A. J. , McALLISTER A. J. , BATRA T. R. , EMSLEY A. E. , DARISSE J. P. F. , ROY G. L. , WINTER K. A. , VESELY J. A.
Published: March 2010

Body weights and measurements were compared among several genetic groups from the 496 Holstein-based H line heifers and 344 Ayrshire-based A line heifers. Differences among herds (Charlottetown, P.E.I., Lennoxville and Normandin, Que.; Ottawa, Ont., and Lethbridge, Alta) were large and highly significant (P < 0.01) for age at first calving and all weights and measurements except birth weight. Year and season of birth effects were small and generally not significant (P > 0.05). Birth weights were 4.1 kg lighter for calves from first parity dams and 1.4 kg lighter for second parity dams than fourth or later parity dams. Heifers calving at earlier ages for the first time were generally heavier and larger at 66 and 82 wk than those calving later, reflecting the effects of concurrent pregnancy. H line heifers were significantly heavier and larger in all measurements than A line heifers. Differences among the Canadian, American, and Research Branch Holstein sire groups were small and generally not significant (P > 0.05). Brown Swiss progeny were significantly (P < 0.05) taller at the withers and longer in the rump and generally larger than progeny of other A line sire groups. Norwegian Red progeny were the most similar to the Brown Swiss, followed by the other Ayrshire groups. Key words: Growth, heifers, Holsteins, Ayrshires, Brown Swiss, Norwegian Red
THE LIPID COMPOSITION OF ERYTHROCYTE MEMBRANES AND PLASMA LIPOPROTEINS IN "DOUBLE-MUSCLED" CATTLE
Authors: BASARAB J. A. , BERG R. T. , THOMPSON J. R.
Published: March 2010

The lipid composition of erythrocyte membranes was determined in 11 phenotypically extreme- and 11 normal-muscled cattle of a "double-muscled" (DM) breed group. The relative concentrations of lipid classes in erythrocyte membranes from extreme- and normal-muscled DM cattle were similar. Significant differences were observed in the relative concentrations of individual fatty acids in the erythrocyte membrane sphingomyelin and phosphatidylethanolamine fractions from extreme-compared with normal-muscled DM cattle. The most notable differences were a higher (P < 0.05) concentration of palmitic acid and a lower (P < 0.01) concentration of oleic acid in sphingomyelin from extreme-muscled DM cattle. In a second study, the total lipid composition of plasma, plasma high density lipoprotein (HDL) and plasma low plus very low density lipoprotein (LDL-VLDL) fractions was determined in six extreme- and six normal-muscled DM cattle. Extreme-muscled DM cattle had a lower (P < 0.05) concentrations of triacylglycerols in all three total lipid fractions and higher (P < 0.05) concentrations of cholesterol in plasma and cholesterol esters in the LDL-VLDL total lipid fraction as compared with normal-muscled DM cattle. The concentration of lysophosphatidylcholine was higher (P < 0.05) in the LDL-VLDL total lipid fraction from extreme-muscled DM cattle, but no other differences in the relative amounts of the phospholipids were observed. Extreme-muscled DM cattle had higher (P < 0.05) concentrations of polyunsaturated fatty acids in the plasma and LDL-VLDL total lipid fractions, with a similar trend occurring in the HDL total lipid fraction. The results of the first study demonstrate a change in fatty acid composition of the membrane, while those of the second indicate an increased rate of VLDL metabolism and/or lower rates of adipose fatty acid turnover in extreme- compared with normal-muscled DM cattle. Key words: Lipid composition, lipoproteins, double muscled cattle
OVARIAN AND ESTROUS ACTIVITY THROUGHOUT THE YEAR IN PREGNANT AND NONPREGNANT EWES SELECTED FOR EXTENDED BREEDING SEASON
Authors: DUFOUR J. J. , FAHMY M. H. , ADELAKOUN V. , MATTON P.
Published: March 2010

Twenty-nine DLS (1/2 Dorset, 1/4 Leicester, 1/4 Suffolk) ewes selected for extended breeding season, were involved in this study which lasted for 18 mo. According to their lambing date relative to January first, 15 ewes had a high lambing index whereas the others had a low index, the difference being 33 days (P < 0.01). Half the ewes were assigned at random to remain nonpregnant throughout the study, whereas the other half was mated in July and August. From 1 May to 15 July, 20 ewes (69%) were cycling of which 81% were from the high and 54% from the low index group (0.05 > P < 0.10). Two ewes (7%) continued cycling throughout the summer, whereas the remaining 18 ewes experienced a period of summer anestrus which occurred on 27 May (± 3.5 days) and lasted for an average of 63 ± 2.6 days. The first ovulation (unaccompanied by estrus) was observed on 29 July (± 2.6 days) the second ovulation, 20 days later was accompanied by estrus. The breeding season in nonpregnant ewes lasted 194 ± 3.2 days ending on 1 Mar. (± 7.3 days). The average lambing date of the 15 pregnant ewes was 8 Jan. (± 2.8 days). Seven of these ewes exhibited at least one ovulation postpartum, but in only two ewes was the ovulation accompanied by estrus. Introducing rams daily indicated that marker rams were successful in detecting only 88% of the ewes in estrus. Sixty-six percent of the false heats were observed prior to resumption of the regular estrous cycle. Key words: Ovarian activity, estrous activity, pregnancy, extended breeding season, estrus detection
EVALUATION OF TWO GLUCOPYRANOSYLAMINES AS SLOW RELEASE NONPROTEIN NITROGEN SUPPLEMENTS FOR CATTLE: AMMONIA ACCUMULATION IN THE RUMEN
Authors: MARTIN P. J. , MILLIGAN L. P. , MATHISON G. W.
Published: March 2010

Four rumen-cannulated steers were utilized to examine the pattern of rumen ammonia accumulation following dosing through the cannula with urea (30 g N), N-[carbamoyl]-β-D(+)-glucopyranosylamine (NCG, 60 g N), N-[N′-hydroxyme-thylcarbamoyl-β-D(+)glucopyranosylamine (HNCG, 60 g N) or soybean meal (60 g N). Urea resulted in maximum increases in rumen ammonia concentration of 33–53 mM within 1–2 h of dosing; twice as much N in the form of NCG did not result in greater, or earlier, rumen ammonia increases. HNCG yielded very little increase (3–10 mM) while soybean meal resulted in small (7–17 mM) increases. Rumen degradation of NCG was less rapid than degradation of urea, but more rapid than soybean meal, or HNCG. The latter appeared more refractive than the plant protein meal. Key words: Glucopyranosylamines, NPN, Cattle, NH3, rumen
COMPOSITION, AMINO ACID DIGESTIBILITIES AND PROTEIN QUALIT OF HIGH-LYSINE BARLEY LINES FOR GROWING RATS
Authors: MISIR R. , SAUER W. C.
Published: March 2010

Hiproly barley and five experimental barley lines bred and grown in Alberta under similar soil and environmental conditions were evaluated as sole protein sources in two rat trials. In exp. 1, compared to Gait barley (control), Hiproly and the test lines (Lines 1, 2 and 3) contained 9–22% more nitrogen (N). Hiproly and Line 1 also contained 21 and 29% more lysine, respectively. Consequently, Line 1 could be classified as a "Hiproly" barley, Line 2 as "high protein" barley and Line 3 a "normal" barley. Determined by the fecal analysis method, lysine was least digestible of the amino acids (AA). Apparent lysine digestibilities were similar for all the barleys. In exp. 2, compared to Gait barley (control), Lines 4 and 5 were similar in N content, but contained 13 and 7.5% more lysine, respectively. Measured by the relative protein value method, there were no differences in performance, reflecting the small differences in lysine content among the barleys. The apparent N digestibilities in barley were 10–11 percentage units lower (P < 0.01) than in casein. Calculated chemical scores showed that among the barleys only Line 1 might adequately provide all the AA, including lysine, for 60- to 100-kg pigs. Key words: High lysine barleys, hiproly, barley lines, apparent digestibilities, relative protein values, rats
POTATO WASTE MEAL. I. COMPOSITIONAL ANALYSES
Authors: HULAN H. W. , PROUDFOOT F. G. , ZARKADAS C. G.
Published: March 2010

Potato waste meal (PW), produced by drying and grinding whole potatoes, potato pulp and peelings, and off-color french fries and potato chips, contained slightly less crude protein (76 g/kg) but more lipid (70 g/kg), crude fiber (40 g/kg) and ash (40 g/kg) compared with corn. Although PW is not devoid of any of the essential or nonessential amino acids, it contained considerably less of each amino acid than corn and appears limiting with respect to methionine and cystine, arginine and the aromatic amino acids. The results suggest that this potato by-product might be considered a substitute ingredient for a proportion of the ground corn in practical diets for poultry and other livestock. Both PW and corn contain up to 0.46 and 0.34 g/kg 4-hydroxyproline, respectively. This discovery indicates that an amino acid previously thought to be confined almost exclusively to the collagens and elastins of vertebrates and invertebrates is in error. Thus, this hydroxyamino acid should no longer be used as an accurate index for assessing connective tissue content or the quality of composite protein supplements containing bone, meat or fish meals. Key words: Potato waste, composition, amino acids
POTATO WASTE MEAL. II. THE NUTRITIVE VALUE AND QUALITY FOR BROILER CHICKEN
Authors: HULAN H. W. , PROUDFOOT F. G. , ZARKADAS C. G.
Published: March 2010

Two experiments were carried out to ascertain the nutritional value of potato waste meal (PW) as a replacement for corn in practical poultry diets using 320 male and 320 female Cobb chicks fed from 1-day-old to 46 days (exp. 1) and 49 days (exp. 2) a basal cereal-based diet containing soybean and fishmeals or test diets each containing 50 g, 100 g, 150 g, 200 g and 300 g PW/kg. In both experiments, the diets were analyzed for elemental and amino acid composition, and the growth responses on the test diets were evaluated individually over a period of 28 days and 46 days or 49 days of ad libitum feeding. Although PW appeared limiting with respect to methionine and cystine, arginine and the aromatic amino acids, it was found that upon supplementation with methionine (0.5 g/kg), the test mixtures exhibited a synergistic effect compared with controls, and that this potato byproduct can be considered a good substitute ingredient for a proportion (200 g/kg) of the ground corn in a practical diet for broiler chickens. Feeding PW at a rate of up to 200 g/kg resulted in optimum biological response and monetary returns. The inclusion of up to 300 g/kg PW in the diets did not increase wetness of the litter or hardness of pellets, two factors reported earlier which could limit the use of PW in animal diets. Key words: Potato waste, nutritive value, broiler chicken
EFFECT OF FEEDING VOMITOXIN-CONTAMINATED WHEAT TO PIGS
Authors: FRIEND D. W. , TRENHOLM H. L. , ELLIOT J. I. , HARTIN K. E. , THOMPSON B. K.
Published: March 2010

Two groups each of three gilts (39 ± 4 kg) were given ad libitum a diet containing 70% vomitoxin-contaminated (1 ppm) wheat (V) and two other groups (controls) the same diet with 70% clean wheat (C). Similarly, for 18 gilts (75 ± 4 kg), two groups were given diet C, two diet V and two groups diet CV containing 35% contaminated and 35% clean wheat. Pigs fed diet V lost weight during the first few days and their weight was less than that of the C pigs; the effect was less pronounced for the CV pigs. Intakes of diets V and CV declined initially then improved; variation in response indicated individual differences in tolerance level during the 21-day experiments. Fifty-six pigs (43 ± 6 kg) were allocated to seven diets and by two sexes in four replicates. Dietary treatments were 0, 14, 28, 42, 56 and 100% vomitoxin-contaminated (1 ppm) wheat in a grower diet with a corn-based diet acting as positive control. There was a linear decrease (P < 0.01) in feed intake with increasing vomitoxin level; weight gains differed significantly in the first week but the differences were not maintained over the 7-wk experimental period. A similar experiment with 56 younger (21 ± 2 kg) pigs for a 4-wk feeding period gave differences in feed intake and weight gain which were not significant; although, differences in gain reached significance (P < 0.05) when positive control data were excluded. Postmortem examinations were undertaken for pigs in all but the first experiment; some discoloration of the stomach and large intestine suggested differences among diets, but none was significant. Key words; Vomitoxin, wheat, pigs, feeding
CALVING PERFORMANCE ASSOCIATED WITH SIRE PREDICTED DIFFERENCES FOR EASE OF CALVING
Authors: SONG H. , WILTON J. W. , SCHAEFFER L. R.
Published: March 2010

Predicted levels of calving performance were obtained for Simmental and Hereford sires with varying proofs for case of calving when used on various ages of cows. Predictions were based on multiple regression from records on the progeny of sires with proofs for calving case in the National Sire Monitoring Program. Values can be used as guidelines by producers to predict calving performance associated with proofs for calving case. Key words: Calving case, beef sire evaluation, beef cattle performance
EVALUATION OF A VITAMIN AND MINERAL REPLACER FOR LIVER IN DIETS FOR MINK (Mustela vison)
Authors: BELZILE R. J.
Published: March 2010

Mink were fed diets containing 10% fresh liver or 1% of a replacer formulated to provide the same amount of vitamins and trace minerals as liver. Compared with a liver-free diet, more growth was obtained among kits fed the replacer diet. But, compared to liver added to a breeder diet, the replacer did not support normal litter size. Key words: Vitamin-mineral replacer, liver, mink growth, mink reproduction
BREED AVERAGES AND AGE OF DAM ADJUSTMENT FACTORS FOR BIRTH WEIGHT OF BEEF CATTLE
Authors: TONG A. K. W.
Published: March 2010

A subset of birth weight records consisting of 191 535 calves, from 7021 herd-years with fewer than 50% estimated weights, tested during 1971 through 1980 was selected from the data files of the Federal-Provincial Record of Performance program for beef cattle to estimate breed averages and age of dam adjustment factors. The main effects included herd-years, breed of sire, breed of dam, sex of calf and age of dam. The interaction effects for breed of sire by sex of calf on birth weight were significant (P < 0.01) and the estimated differences for 22 breeds of sire expressed as deviations from the Hereford breed ranged from − 4.05 to 6.27 kg for male calves and from − 3.70 to 6.20 kg for female calves. The effects of breed of dam, sex of calf, age of dam and all the two-way interactions were significant at P < 0.01, while the three-way interaction was significant at P < 0.05. Additive age of dam adjustment factors within sex of calf were derived for 12 breeds of dam. The general age of dam effects averaged over breed of sire and breed of dam, expressed as deviations from the mature dams, were − 2.69, − 1.27, − 0.41, 0 kg for male calves, and − 2.64, − 1.26, − 0.50, 0 kg for female calves from 2-, 3-, 4-, and 5 + yr-old dams. Key words: Birth weight, breed averages, age of dam adjustment factors
PROGENY GROUP SIZE IN AN ORGANIZED PROGENY TEST PROGRAM OF AI BEEF BULLS USING REFERENCE SIRES
Authors: FOULLEY J. L. , SCHAEFFER L. R. , SONG H. , WILTON J. W.
Published: March 2010

A numerical procedure was utilized to optimize the number of progeny for young bulls and reference sires in a beef sire progeny testing program. Optimization was based on attaining a desired level of accuracy on the types of comparisons that were to be made after the test was completed. As heritability increased, the total number of progeny required decreased, but the percentage of reference sire progeny remained the same. There were near optimum progeny distributions with smaller total number of progeny and only slightly less accurate than the optimum solutions which could also be considered for application. Key words: Progeny testing, beef cattle, optimum designs, reference sires
DIFFERENCES BETWEEN SIRE GROUPS IN BODY MEASUREMENTS AND BODY WEIGHT CHANGES OF LACTATING COWS
Authors: LIN C. Y. , BATRA T. R. , McALLISTER A. J. , LEE A. J. , DARISSE J. P. F. , ROY G. L. , VESELY J. A. , WINTER K. A.
Published: March 2010

Body weights and measurements of 694 first, 519 second and 329 third lactation cows in five Research Branch herds of the National Cooperative Dairy Cattle Breeding Project of Agriculture Canada were studied. The A line cows were daughters of U.S., Canadian and Finnish Ayrshire proven bulls, Brown Swiss and Norwegian Red proven bulls and young Research Branch Ayshire bulls and Research Branch Ayrshire cows. Highly selected U.S. and Canadian Holstein proven bulls and young Research Branch bulls mated to Research Branch Holstein cows produced the H-line cows. The model for analysis contained fixed effects for station, year of birth, line, sire group within line and sire within sire group within line as classification variables and age at calving as a covariable. Sire group, line, station and sire had significant effects on all weights studied. However, most effects were not significant for weight changes. Daughters of Brown Swiss and Norwegian Red sires were nearly as heavy as the daughters of Holstein bulls. On average, cows lost about 20 kg of weight from calving to 56 days postpartum of first lactation. The older first calvers were found to lose more weight from calving to 56 days of first lactation and gain less weight from 56 days postpartum onward than the younger first calvers. The effects of station, line and age at calving were significant for most body measurements. Sire group effects were significant for 13 out of 24 measurements. Significant differences between sire groups existed in stature (withers height) at all lactations and ages. In contrast, body length (shoulder to hook) did not differ significantly between sire groups from 112 days of first lactation onward. Key words: Body weight changes, body measurements, dairy cattle
HERITABILITY OF NONRETURN RATE OF CANADIAN HOLSTEIN-FRIESIAN BULLS
Authors: MURRAY B. B. , SCHAEFFER L. R. , BURNSIDE E. B.
Published: March 2010

Conception rates of Canadian Holstein-Friesian bulls in artificial insemination were recorded as percent 60- to 90-day nonreturns to first service. A total of 5, 923, 974 first services to 784 bulls by 207 sires were analyzed using a mixed model which included age of bull (1–14 yr), years (1956–1976), months and AI units as fixed effects. Bulls and sires of bulls were random. Significant differences were found in all classifications involving fixed effects. Nonreturn rates at one year of age were highest and significantly different from nonreturn rates at 9 yr of age and older. Lowest estimates of nonreturn rates were in January and December, and highest were in September and October. Differences were found among some AI units. Best linear unbiased predictions of differences among all service sires were obtained. Variance components were estimated iteratively by maximum likelihood. Heritability was 0.25 by regression of sire on son with 30 sires having four or more sons. Repeatability was 0.41. Many factors affecting nonreturn rates could not be identified, especially at the cow or herd level. Sire selection programs in AI units for high nonreturn rates in sires of young bulls should be successful. Key words: Fertility, dairy bulls, heritability
MASS SELECTION FOR POSTWEANING GROWTH IN SWINE. VI. MEANS, HERITABILITIES, GENETIC AND PHENOTYPIC CORRELATIONS, AND CORRELATED RESPONSE OF CARCASS TRAITS
Authors: RAHNEFELD G. W. , CLIPLEF R. L. , GARNETT I. , McKAY R. M.
Published: March 2010

Means, heritabilities, genetic and phenotypic correlations, and correlated responses in carcass traits (total carcass backfat, carcass length, area 1. dorsi, ham weight, percentage ham of side, percentage lean in ham face, color score, texture score, and marbling score) during 11 generations of selection for postweaning average daily gain were studied on a selected Lacombe line, a Yorkshire control line, and a crossbred Lacombe × Yorkshire group generated each year from the two lines. With the exception of color score, the heritability estimates were moderate to high. Genetic and phenotypic correlations between average daily gain and the carcass traits ranged from − 0.16 to 0.46 and from − 0.07 to 0.15, respectively. Correlated responses in the carcass traits were very small. Key words: Swine, carcass traits, selection, heritabilities, correlations
EFFICACY OF COMPUDOSE® AS A GROWTH PROMOTANT IMPLANT FOR GROWING-FINISHING STEERS
Authors: MATHISON G. W. , STOBBS L. A.
Published: March 2010

Compudose®, a growth promotant implant for cattle which gives a sustained release of estradiol-17β over a relatively long period of time, was evaluated in a 140-day trial with 80 growing-finishing cattle. An average of 96.9 (± 0.53 SE) μg of estradiol-17β was released daily from these implants. Implanted cattle gained 15.0% faster, ate 7.6% more feed daily and required 6.7% less feed per unit of gain than control steers. Steers which had received Compudose® had 17 kg larger carcasses when slaughtered and a higher dressing percentage. It was concluded that Compudose® is a good growth promotant implant for growing-finishing steers and has the advantage that a single implant can be used in the finishing period. Key words: Compudose, estradiol, growth promotant, implant, cattle
THE MINERAL CONTENT OF TIMOTHY GROWN IN PRINCE EDWARD ISLAND
Authors: WINTER KARL A. , GUPTA UMESH C.
Published: March 2010

Timothy (Phleum pratense L.) samples from 107 sites throughout Prince Edward Island were obtained at the early heading stage and analyzed for Ca, P, K, Mg, Cu, Mo, S, Mn, Zn and Fe. The mean tissue contents of these minerals were: Ca, 0.25%; P, 0.24%; K, 2.12%; Mg, 0.10%; Cu, 4.5 ppm; Mo, 0.37 ppm; S, 0.12%; Mn, 31.1 ppm; Zn, 26.8 ppm and Fe, 30.5 ppm. When compared with the requirements of cattle and sheep Ca would be deficient for most age and production categories and the mean timothy Ca content was lower than published values. The Ca: P ratio was low at approximately 1:1. Mean Mg content of timothy was low relative to animals' requirements, which, combined with the low Ca and high K content of a number of samples, indicated there was a risk of grass tetany in grazing animals. Most trace elements were barely adequate or deficient relative to the needs of cattle and sheep. Copper, for example, at 4.5 ppm is deficient for cattle but lack of deficiency problems was attributed to correspondingly low Mo and S levels. The need for adequate Ca and P supplementation and the use of a suitable trace-mineralized salt is recommended in formulating diets for dairy cattle, beef cattle, and sheep. Key words: Timothy, forage, minerals, deficiency, cattle, sheep
UREA METABOLISM IN STEERS FED MATURE GRASS HAY AND GIVEN FRESH OR SALT WATER
Authors: DIXON R. M. , MILLIGAN L. P.
Published: March 2010

Four steers given 5.5 kg/day of mature mixed temperate species of grass hay at 2-h intervals and consuming either fresh water or water containing 1% (wt/vol) NaCl were used in a study of urea metabolism. 14C-urea and H14CO3− tracers were used to measure the rate of irreversible loss from the plasma urea pool and the rate of transfer of plasma urea to the rumen. Rate of excretion of urea in urine and degradation of plasma urea in the postruminal gastrointestinal tract were also measured. Despite a large increase in urinary volume there was no effect of salt water ingestion on urinary urea excretion or the amount and site of urea degradation in the gastrointestinal tract. On average the rate of irreversible loss of plasma urea was 36.1 g N/day, of which 9.7 g N/day were excreted in urine. Degradation in the rumen was 17.9 g N/day or 68% of total urea degradation, and this was equivalent to a clearance of urea to the rumen of 392 L/day. This transfer of plasma urea to the rumen was equal to 27% of dietary N intake. Transfer of plasma urea to the rumen was much more extensive than previously observed in cattle fed tropical forage diets, but was similar to that obtained in experiments with cattle fed tropical forage plus sugar, or sheep fed high intakes of bromegrass hay. Key words: Urea metabolism, salt
FLOW AND SOLUBLE PROPORTIONS OF ZINC, MANGANESE, COPPER AND IRON IN THE GASTROINTESTINAL TRACT OF SHEEP FED CORN OR ALFALFA SILAGES
Authors: IVAN M. , VEIRA D. M. , IHNAT M.
Published: March 2010

A set of four sheep, each fitted with a rumen cannula and a re-entrant cannula in the ascending duodenum and terminal ileum, were used for collection of rumen, duodenal and ileal digesta. A second set of four normal sheep was used for collection of feces and urine. The sheep were fed corn silage, urea-added corn silage, formic acid-treated alfalfa silage or wilted alfalfa silage in latin square design. Soluble proportions of manganese in rumen fluid, ileal digesta and feces were much lower on alfalfa silages than on corn silages although the soluble proportions in the duodenal digesta were not different. The soluble proportions of zinc, copper and iron were not as consistent as those of manganese. The apparent absorption of zinc was negative on alfalfa silages, and was associated with the lower soluble proportion of zinc in duodenal digesta and higher in the ileal digesta, as compared to corn silages. The apparent absorption of iron was much higher on corn silages than on alfalfa silages. Addition of urea to corn at ensiling resulted in an improvement of apparent absorption of copper. Key words: Trace elements, solubility, absorption, corn silage, alfalfa silage, sheep
THE EFFECTS OF CALCIUM CARBONATE ON THE APPARENT DIGESTIBILITY, SERUM CONCENTRATION AND APPARENT RETENTION OF DIETARY MINERALS IN DAIRY CATTLE
Authors: CATHCART E. B. , SHELFORD J. A. , PETERSON R. G.
Published: March 2010

CaCO3 was added to a hay-grain ration already adequate in nutrients to determine the effect of doubling the Ca content of the ration on apparent digestibilities and serum levels of 11 minerals. Sixteen dairy cattle of two breeds (Holstein and Ayrshire) were randomly assigned to the control (0.7% Ca) or Ca-treatment (1.5% Ca) based on calving order. Each animal was fed to appetite for 80 days postpartum with no difference (P > 0.05) occurring between treatments in intake when expressed as a percentage of body weight. Five animals from each treatment were exposed to a 5-day digestibility trial. No change in organic matter apparent digestibility occurred but there were higher (P < 0.05) levels of Ca and Fe, increased (P < 0.01) levels of Cu, and lower (P < 0.05) Zn and Mo apparent digestibilities for animals on the Ca-treatment. Fecal pH was higher (P < 0.05) in the Ca-treated cows indicating a buffering action of the added CaCO3. In the serum, Ca and Zn concentrations were higher (P < 0.01), Cu increased (P < 0.05), and P was lower (P < 0.01) than the levels for the control animals. Breed effects were discernible as both P and Cu were higher (P < 0.01) in the serum of Ayrshires than of Holsteins. No change (P < 0.05) was evident in the secretion of minerals into the milk but urinary P concentration was higher (P < 0.05) in the control group. CaCO3 supplementation of the diet allowed the animals to go from a negative to a positive Ca balance (P < 0.01) and increased (P < 0.05) the amount of P apparent retention. In all, six essential minerals had altered apparent digestibilities and/or serum concentrations with possible long-term effects on animal metabolism. Key words: Calcium, mineral balance, digestibility, serum, dairy cattle
EFFECT OF HULL AND PROTEIN CONTENTS OF BARLEY ON PROTEIN AND ENERGY DIGESTIBILITY AND FEEDING VALUE FOR PIGS
Authors: BELL J. M. , SHIRES A. , KEITH M. O.
Published: March 2010

Sixteen simulated barleys, containing combinations of 7.27, 11.27, 15.17 and 19.27 crude protein (CP) (air-dry basis) and 0, 10, 20 and 30% hulls, were made from barley (Hordeum vulgare L. 'Bonanza') that was finely ground and air-classified into hulls, starch, protein and fines fractions. These barleys were supplemented with vitamins and minerals and fed in four replicates to 16 pigs, of 20 kg initial weight, in a digestibility trial. Energy digestibility was highly correlated with percent hulls and percent crude fiber (r = − 0.9 for both factors; P < 0.01). Digestible energy prediction values were developed whereby barley with 0% hulls was 84% digestible and had 15.73 kJ DE/g dry matter; barley with 30% hulls was 64% digestible and contained 12.01 kJ DE/g. The gross energy of hulls was 17.5% digestible and contained 2.94 kJ/g. Apparent digestibility of protein decreased (P < 0.05) from 75.0 to 72.0% as hulls increased from 0 to 30% and from 82.2 to 62.5% as dietary CP increased from 21.9 to 8.0% (dry matter basis). Metabolic fecal protein (N × 6.25) increased from 1.49 to 2.79 g/100 g dietary dry matter as hulls increased from 0 to 30%. Apparent digestibility of hull protein, when fed in 16% CP diets, was 44% and the corresponding value for nonhull barley protein was about 75%. A tentative monetary evaluation of barleys varying in CP and hull or crude fiber contents relative to prices of a reference barley and soybean meal was presented. Key words: Barley, hulls, protein, digestibility, feeding value, pigs
LYSINE REQUIREMENT OF PIGS WEIGHING 7 TO 19 KG LIVEWEIGHT
Authors: AHERNE F. X. , NIELSEN H. E.
Published: March 2010

One hundred and forty-four crossbred pigs, weaned at 4 wk of age at an average initial weight of 7.0 kg were allotted to six dietary treatments. The diets were formulated to contain two protein levels (18 and 20%) and three lysine levels (1.0, 1.15 and 1.30%). There were no significant differences (P > 0.05) in the feed intake of pigs fed any of the six diets. Growth rate and feed efficiency of pigs were significantly improved by increasing the protein level in the diet from 18% to 20%. At both the 18% and 20% dietary protein levels there was a significant improvement in growth rate and feed efficiency as lysine level in the diet was increased from 1.0 to 1.15% but an increase from 1.15 to 1.30% tended to decrease these performance criteria. The data suggest that rapidly growing pigs fed barley-wheat-soybean-meal-based diets have a dietary requirement for 20% protein and approximately 1.15% lysine over the range 7–19 kg liveweight. Key words: Lysine, protein, requirement, starter pigs
EVALUATION OF BEEF SIRES FOR MATERNAL GENETIC EFFECTS ON WEANING WEIGHT AND MEASUREMENT OF GENETIC TRENDS
Authors: CROW G. H. , HOWELL W. E.
Published: March 2010

Procedures for evaluating beef sires for maternal genetic effects for weaning weight were developed and used in the calculation of genetic trends. Using the maternal grandsire (MGS) and error variance components, predicted differences (PDs) of MGSs for parity one daughter performance were calculated using Record of Performance data from the Angus, Charolais and Hereford breeds. Best linear unbiased prediction (BLUP) methods were used with a mixed model which included herd-year and MGS effects. The average number of daughter records per MGS was 5.44, 5.26 and 5.12 for Angus, Hereford and Charolais, respectively. As a result of these small numbers of daughter records, the PDs of most MGSs had very large standard errors of prediction. Weighted averages of MGS PDs for each breed in each of the 5 years from 1975 to 1979 were calculated to determine if there was any genetic trend in MGS PDs. There were small trends evident but not sufficient to indicate that any selection pressure was being exerted on maternal ability. Key words: Beef sire evaluation, maternal effects, genetic trends
SEX AND YEAR EFFECTS ON CARCASS CHARACTERISTICS OF THREE-WAY CROSS BEEF CATTLE REARED AT TWO LOCATIONS
Authors: RAHNEFELD G. W. , FREDEEN H. T. , WEISS G. M. , NEWMAN J. A. , LAWSON J. E.
Published: March 2010

From 1973 to 1978, 3673 steers and heifers sired by Charolais (C), Simmental (S), Limousin (L) or Chianina (Chi) were born to first-cross dams under farm (Brandon, Man.) and range (Manyberries, Alta.) conditions. Dam crosses included the Hereford × Angus (HA) and crosses sired by C, S or L sires and out of H, A or Shorthorn (N) dams. All calves entered the feedlot at approximately 206 days of age. Brandon calves, fed at that location were brought to full feed (100% grain concentrate) by 220 days of age. Manyberries calves, fed at Lacombe, received a ration of cereal silage and grain concentrate with the silage component reducing from 70% to 30% over a period of 5 mo. The minimum slaughter age was 13.5 mo at both locations but age alone (13.5 and 15 mo) was the slaughter criterion at Brandon whereas Lacombe employed the dual criteria of liveweight and degree of finish. These location differences in feeding and slaughter criteria resulted in greater slaughter weights (278 vs. 265 kg), greater rib fat (1.61 and 1.09 cm) and a higher percentage of kidney fat (2.09 vs. 1.75%) for the Brandon animals. They were also reflected in the sex differences for age at slaughter (sexes equal at Brandon; heifers > steers at Lacombe) and degree of finish (sexes equal in rib fat at Lacombe; steers > heifers at Brandon). Heifers at Brandon had a larger percentage of hide (P < 0.0001) and lower dressing percentage (P < 0.0001) than steers. Percentage of head, front feet and hind feet were also less for heifers than steers at this location. Rib eye was greater for steers but heifers had greater rib eye area per unit weight (P < 0.0001) and a higher percentage of kidney fat (P < 0.0001). The sex ranking for percentage chuck, shank and flank was steers > heifers (P < 0.0001) and the reverse for percentages of rib, long loin and the combined cuts of rib, round and long loin (P < 0.0001). For percentages of lean in the long loin, rib and chuck the ranking was steers > heifers (P < 0.0001) with heifers > steers for percentage lean of round (P < 0.0001). Heifers relative to steers had significantly (P = 0.0001) lower percentages of bone in the round, rib and chuck and greater (P = 0.0001) lean to bone ratios for the combined trait of long loin and round. The sex differences observed at Lacombe for these traits were in good agreement with Brandon although sex by location interaction was not tested. Year differences were large but year-by-sex interactions were non-existent for virtually all carcass traits evaluated at both locations (P ≤ 0.05). Sire-by-sex and dam-by-sex interactions were also absent. Key words: Beef cattle, crossbreeding, carcass characteristics, year effects, sex effects
ENDOCRINE PROFILES AND FUNCTIONAL CHARACTERISTICS OF CORPORA LUTEA FOLLOWING ONSET OF POSTPARTUM OVARIAN ACTIVITY IN BEEF COWS
Authors: MANNS J. G. , HUMPHREY W. D. , FLOOD P. F. , MAPLETOFT R. J. , RAWLINGS N. , CHENG K. W.
Published: March 2010

Three experiments were conducted to evaluate endocrine profiles and to determine the morphological and functional characteristics of corpora lutea (CL) following the onset of postpartum ovarian activity in beef cows, suckled by a single calf once daily. In exp. 1, blood samples were collected from 12 cows at 6-h intervals beginning 25 days postpartum until ovariectomy which was carried out on each of two cows on days 25, 27, 29, 31, 33, 35 after parturition. Ovarian structures were examined grossly and histologically. In exp. 2, blood samples were collected from eight cows at 6-h intervals for 18 days beginning 25 days postpartum and at less frequent intervals thereafter. Laparotomies were carried out on day 36 after calving, the ovaries were observed, CL were sampled and the residual tissue was marked with charcoal. A second laparotomy was performed on day 50. Luteal tissue samples were processed and examined by light and electron microscopy. Luteal cell types were evaluated, percent of area covered by large cells was determined and average luteal cell diameter was calculated. In exp. 3, seven cows were bled daily from parturition until day 25 postpartum. Serum from all experiments was assayed for progesterone (P4), FSH, LH and a prostaglandin metabolite (PGFM). The data showed that serum PGFM levels declined from a peak at calving to basal levels by 10 days postpartum which was well before the first ovulation. In all instances the observed peaks of serum LH and serum FSH preceded the first rise in P4 which, in eight of nine cases, was due to a functional CL. These CL were functional for periods of time ranging from 3 to 12 days. The regression of short-lived CL appeared abnormal compared to the longer-lived CL in which regression was characterized by a rapid decline in P4 and elevated blood PGFM. These data show clearly that the first increase in P4 is preceded by a typical LH surge, followed by ovulation and CL formation which has a variable life-span. Key words: Beef cows, postpartum, anestrus, corpus luteum.
BUTYRATE:ACETOACETYL-CoA TRANSFERASE ACTIVITY IN BOVINE RUMEN EPITHELIUM
Authors: EMMANUEL B. , MILLIGAN L. P.
Published: March 2010

Enzymatic activity catalyzing transacylation between butyrate and acetoacetyl-CoA was detected in homogenate and cell-free extracts of bovine rumen epithelium which was obtained fresh from the slaughter house. The enzyme is active over a wide pH range with the maximum between 6.5 and 8.0. The rate of disappearance of acetoacetyl-CoA at 310 nm in the presence of butyrate was 19 μmol/h per gram wet weight tissue at 22 °C. When acetate and propionate were used as substrates, acetoacetyl-CoA removal rates were 8.7 and 14.5 μmol/h per gram wet weight, respectively. Acetoacetate, the product of the transferase reaction was measured enzymatically. Other products formed including acetyl-CoA, propionyl-CoA and butyryl-CoA were identified chromatographically. This transacylation reaction has an impact on energy conservation in the rumen epithelium. Activities of 3-oxo acid CoA transferase (EC 2.8.3.5) and D(–)-3-hydroxybutyrate dehydrogenase (EC 1.1.1.30), key enzymes in rumen epithelial ketogenesis, were 26 and 16 μmol/h per gram wet weight tissue. Key words: Butyrate:acetoacetyl-CoA transferase, bovine, rumen, epithelium
AVOPARCIN, MONENSIN AND ZERANOL FOR STEERS FINISHING ON BARLEY DIETS
Authors: COHEN R. D. H. , COOPER J. A.
Published: March 2010

Ninety Hereford steers, weighting 362 ± 30 kg, were allocated to three replications of six treatments as follows: basal diet which consisted of 5.9 ± 0.73 kg·head−1∙day−1 steam-rolled barley at the start of the trial (78% of total diet) increasing to 10.1 ± 0.52 kg·head−1∙day−1 by the end of the trial (85% of total diet), 0.72 kg·head−1∙day−1 grass hay and 1 kg of mineral/vitamin supplement; basal diet to which 400 mg·head−1∙day−1 avoparcin was added via the mineral supplement; basal ration with added monensin given via the mineral supplement at 280 mg·head−1∙day−1; basal diet with an ear implant of zeranol; basal diet, avoparcin and zeranol; basal diet, monensin and zeranol. Average daily liveweight gains (ADG), feed intakes and carcass characteristics were measured and feed:gain ratios were calculated. Avoparcin, monensin and zeranol, when given alone, did not significantly influence any measured production trait. However, avoparcin and zeranol, when given together, increased ADG by 20.3% and reduced feed:gain ratio by 15.3% (P < 0.05). Similarly, monensin and zeranol in combination increased ADG by 24.6% and reduced feed:gain ratio by 20.7% (P < 0.05). Carcass characteristics were not influenced by any of the treatments. Key words: Avoparcin, monensin, zeranol, barley, beef steers
EFFECT OF DIETARY SUPPLEMENTATION OF VITAMIN C ON PIG PERFORMANCE AND THE INCIDENCE OF OSTEOCHONDROSIS IN ELBOW AND STIFLE JOINTS IN YOUNG GROWING SWINE
Authors: NAKANO T. , AHERNE F. X. , THOMPSON J. R.
Published: March 2010

Seventy-two, 4-wk-old weanling pigs averaging 6.9 kg were assigned to three treatments consisting of a 19% crude protein starter diet to which 0, 350 or 700 ppm vitamin C were added. After a feeding period of 44 days, the crude protein level of the diet was decreased to 16% but vitamin C supplementation continued at the same level throughout the growing-finishing phase. At approximately 90 kg body weight, pigs were slaughtered, and elbow and stifle joints were examined for soundness. Average daily gain, average feed intake and feed:gain ratios, measured for each week or for the whole period of the starter phase, were similar among pigs fed vitamin-C-supplemented diets and those fed the control diet. There were also no significant treatment differences in performance of growing-finishing pigs. Plasma vitamin C concentration of pigs, measured during the growing-finishing phase, was significantly (P < 0.01) increased by dietary supplementation of vitamin C. Locomotory ability was similar between pigs fed 350 ppm supplemental vitamin C and control pigs, but appeared to be superior (P < 0.05) for pigs fed 700 ppm supplemental vitamin C. Dietary supplementation of vitamin C did not reduce the incidence and severity of osteochondral lesions in the elbow and stifle joints of the pigs. The medial femoral condyle, the medial humeral condyle, and the proximal ulna were the major joint sites affected. Positive correlations were observed between average daily gain and locomotory ability scores (r = 0.45, P < 0.01), and average daily gain and soundness scores of the distal humerus (r = 0.42, P < 0.01). Dietary supplementation of vitamin C did not significantly influence hydroxyproline concentrations of the lateral femoral condylar cartilage. Key words: Vitamin C supplementation, plasma vitamin C, osteochondrosis, pigs, hydroxyproline
EFFECTS OF DIETARY ASPIRIN (ACETYLSALICYLIC ACID) ON THE INCIDENCE OF SUDDEN DEATH SYNDROME AND THE GENERAL PERFORMANCE OF BROILER CHICKENS
Authors: PROUDFOOT F. G. , HULAN H. W.
Published: March 2010

A total of 2400 broiler chickens were used in four experiments to estimate the effects of using 0.04, 0.08 and 0.16% aspirin (ASA) as dietary supplements. Not only did the ASA dietary supplementation have no significant (P < 0.05) beneficial effect on the incidence of sudden death syndrome but it also had a deleterious effect on overall mortality which was significant (P < 0.01) in two of the four experiments. Furthermore, the addition of ASA at 0.16% to the diet resulted in reduced body weights which were significant at P < 0.05 in two experiments and at P < 0.10 in the other two experiments. Key words: Aspirin, sudden death syndrome, broiler chickens, growth rate
LIPID ACCUMULATION IN YOUNG AND MATURE CULL HOLSTEIN COWS FED A HIGH ENERGY DIET
Authors: JONES S. D. M. , SZKOTNICKI J. E.
Published: March 2010

Eleven young and eight mature lean Holstein cows were fed a high energy (high moisture corn and haylage) diet to appetite. In addition, six young and six mature cows were slaughtered at the start of the trial to estimate initial body composition. The cows were slaughtered at random over a period ranging from 68 to 103 days after start on feed. The left side of each carcass was broken into eight wholesale cuts that were further separated into bone, lean tissue and fat (subcutaneous and intermuscular). The lean and fat tissues from each meat cut were ground separately and analyzed for their moisture and lipid contents. Mature cows had significantly more lipid in the fat depots of three meat cuts (average increase of 84 g lipid/kg adipose tissue) than young cows at the start of the trial, but the overall effect of cow maturity on meat cut composition was minor. The feeding period, however, resulted in large significant increases in the lipid content of all meat cuts. Averaged over the eight meat cuts, the lipid contents of lean tissue, intermuscular and subcutaneous fat increased by 55.9%, 16.5% and 17.6%, respectively. There were no maturity differences in the rate of lipid accumulation indicating that young and mature cows had a similar pattern of lipid accumulation as they increased in size. Rate of lipid accumulation in subcutaneous fat was highest for the shank and rib and lowest for the flank and hip (growth coefficients were 1.54, 1.29, 0.68 and 0.68). Rate of lipid accumulation in the intermuscular fat was highest in the chuck and flank and lowest for the brisket, plate and hip (growth coefficients were 1.92, 1.85, 0.57, 0.59, and 0.64). Rate of lipid accumulation in lean tissue from all the meat cuts (intermuscular fat) was highest for the shank and brisket and lowest in the plate (growth coefficients were 1.37, 1.19 and 0.67). It was concluded that the lipid contents of lean and fat tissue from young and mature cull Holstein cows followed a pattern of differential accumulation, and that there was a major increase in lipid concentration in all fat tissue and lean from each of the meat cuts as fattening proceeded. Key words: Cows, chemical composition, carcass, lipid
EVALUATION OF CONCENTRATED WHEY AND CANOLA MEAL MIXTURE AS A SUBSTITUTE FOR GRAIN IN THE RATIONS OF CALVES
Authors: FISHER L. J.
Published: March 2010

Twenty-four male Holstein calves averaging 117 kg body weight were each randomly assigned to one of four treatments: I, grain mixture, 2.0 kg·animal−1∙day−1; II, evaporated whey-canola meal mixture (EWC), 1.0 kg∙animal−1∙day−1; III, EWC, 2.0 kg·animal−1∙day−1; and IV, EWC, 4.0 kg∙animal−1∙day−1. All four groups were fed hay free choice. The effect of level of whey feeding on body weight gain, rumen fermentation and plasma minerals was then measured over a period of 120 days. The intake of EWC dry matter (DM) was 17.2, 34.4 and 55.5% of total DM intake for treatments II, III and IV, respectively, while the grain mixture represented 42.8% of DM intake for treatment I. Body weight gain during the 4-mo feeding period averaged 1.00, 0.93, 1.00 and 1.12 kg/day for treatments I–IV, respectively. Level of whey feeding had a marked influence on rumen fermentation. The molar proportion of rumen acetate was significantly lower and that of butyrate and valerate were significantly higher for treatments II and IV compared with treatments I and II. The effect of level of whey feeding on blood metabolites was less consistent although there was a trend towards a lower hematocrit and blood urea nitrogen levels with the highest level of whey feeding. The results of this trial indicated that the feeding of the EWC product at 2.0 and 4.0 kg/day caused a marked change in rumen fermentation but was a suitable source of energy for growing calves fed hay. Key words: Whey, utilization, dairy calves, rumen volatile acids