bluuebunny/crossref_metadata_2025 huggingface dataset:
Degradability and digestibility of full-fat soybeans treated with different sugar and heat combinations
Authors: Petit Hélène V. , Tremblay Gaëtan F. , Marcotte Michèle , Audy Richard
Published: March 2010

Two experiments were conducted to study the effects of different combinations of sugars and heating time and temperature on the ruminal undegradable protein fraction and DM digestibility of full-fat soybeans. In the first experiment, the influence of sugar addition before heating (none, soaked in either a high fructose corn syrup [HFCS] solution, lignosulfonate or molasses), micronization temperatures (100, 110, 120, and 130 °C), and temperature holding times (0, 30, 60, and 120 min) was examined in a 4 × 4 × 4 factorial arrangement of treatments. In the second experiment, the effect of heating in a sugar solution was studied in a 4 × 2 × 4 factorial design with four sugar treatments (none, soaked either in fructose, molasses or a high xylose product), two soaking temperatures (100 and 120 °C), and four soaking times (0, 60, 120, and 240 min). In vitro dry matter digestibility (IVDMD), in vitro ruminal undegradable protein (RUP), and in sacco RUP were measured. In the first experiment, increased temperatures and heating to 120 min resulted in an increased RUP fraction of full-fat soybeans with no effect on DM digestibility, relative to when no sugar or fructose was added. There was a decrease in digestibility with increased temperature when lignosulfonate or molasses was added and with increased heating time when lignosulfonate was added. In the second experiment where soaking in sugar and heating were done simultaneously, lignosulfonate increased the RUP of soybeans without affecting its digestibility but values were numerically lower than when soaking and micronizing were conducted in two different steps as performed in the first experiment. Key words: protein, degradability, digestibility, micronization
The use of double-muscled cattle breeds in terminal crosses: Meat quality
Authors: Gariépy C. , Seoane J. R. , Cloteau C. , Martin J. F. , Roy G. L.
Published: March 2010

The purpose of this study was to assess the quality of meat from 84 calves born from British (50% Hereford and 50% Red Angus) and Continental (50% Simmental and 50% Maine Anjou) dams inseminated with semen from normal (Charolais) or double-muscled (Piedmontese, Belgian Blue) sires. Lean composition of Belgian Blue and Piedmontese sired cattle had less intramuscular fat and more protein than Charolais sired cattle (P < 0.01 to 0.05). Breed of sire, origin of dam or calf sex had no effect on longissimus ultimate pH, thawing and cooking losses, shear forces, tenderness and overall flavour. However, meat from male progeny displayed higher drip loss (P < 0.05) and meat colour of male calves born from British dams was slightly more saturated than that of male calves born from Continental dams (P < 0.02). There were no other single effects of parental traits on meat quality. Significant interactions on total and soluble collagen content involving parental traits together with the single sex effect of the progeny (P < 0.05) did not induce textural differences, but meat from male progeny and that from Continental dams crossed with Belgian Blue sires was more juicy (P < 0.05). The use of DM bulls in terminal crosses resulted in increased lean yield and less marbling of the meat of the progeny but did not exert any other important effect on meat quality. Key words: Beef, double-muscling, meat quality
Growth, carcass and meat quality characteristics of beef cattle with 0, 50 and 75 percent Wagyu genetic influence
Authors: Mir P. S. , Bailey D. R. C. , Mir Z. , Entz T. , Jones S. D. M. , Tson W. M. Rober , Weselake R. J. , Lozeman F. J.
Published: March 2010

Feeding trials were conducted in two years to compare growth performance, carcass characteristics and quality of meat from beef cattle with 0, 50 or 75% Wagyu genetic influence. The cattle types used in the two years of the study were Continental crossbred steers (0% Wagyu), cattle with 50% Wagyu influence (Wagyu/Angus crossbreds) and 75% Wagyu influence (containing 25% from other European breeds). Cattle were housed in individual pens in the first year and in group pens in the second year. Cattle were fed a backgrounding diet containing 35% barley grain and 65% barley silage with protein, mineral and vitamin supplements until they weighed more than 380 kg, after which they were adapted to a finishing diet consisting of 80% barley and 20% barley silage with mineral and vitamin supplements. Cattle were weighed every 4 wk and at the end of the finishing period they were processed and carcass information was obtained. A three-rib section (10–12) was removed from 41 (year 1) and 44 (year 2) carcasses selected randomly from each group, and Warner–Bratzler shear force was determined. The year-by-cattle type interaction was significant for most parameters; thus all the data were also analysed by year using weight of cattle at initiation of the feeding trial as a covariate for the backgrounding and finishing phases of growth and using carcass weight and back fat depth as covariates for carcass and meat-quality parameters. Weight at the start of the trial influenced most growth parameters and age at slaughter. Continental crossbred steers had higher (P < 0.05) ADG than Wagyu crossbred cattle during the finishing phase (1.47 vs. 0.82 kg d−1) in year 1, but not in year 2. Carcass weights of 75% Wagyu crossbred cattle were lower (P < 0.05) than those of Continental crossbred steers in both years. Warner–Bratzler shear force values were less than 5.3 kg to shear cores of 19 mm diameter. However, 92% in year 1 and 71% in year 2 of the carcasses from Wagyu crossbred cattle graded Canada AAA, and contained more than a "small" amount of intramuscular fat. Thirty percent of the carcasses from Wagyu crossbred cattle in year 1 graded Canada Prime. Only 30% of Continental crossbred steers in year 1 and 10% in year 2 graded Canada AAA. Wagyu genetic influence enhanced marbling in beef cattle without loss in carcass size for the 50% Wagyu steers. Key words: Wagyu, Carcass characteristics, Warner–Bratzler shear force
Insulin and glucagon responses to intravenous injections of glucose, arginine and propionate in lactating cows and growing calves
Authors: Sano H. , Arai H. , Takahashi A. , Takahashi H. , Terashima Y.
Published: March 2010

Plasma insulin and glucagon responses to glucose, arginine and propionate injections were measured to establish indicators of the endocrine status in lactating cows and growing calves. The metabolites were intravenously injected at a dose of 0.625 mmol kg−1 and the time courses of changes in plasma insulin and glucagon concentrations were determined. Basal plasma glucagon concentrations were higher (P < 0.05) for lactating cows than for growing calves, while basal plasma insulin concentrations did not differ between animal groups. Concentrations of plasma insulin increased (P < 0.01) after glucose injection, whereas plasma glucagon concentrations decreased in both lactating cows (P < 0.05) and growing calves (P < 0.01). Plasma insulin and glucagon concentrations increased in response to arginine (P < 0.01) and propionate (P < 0.01 except insulin for lactating cows at P < 0.05) injections. Plasma insulin and glucagon responses were greater (P < 0.05) to arginine than to glucose or propionate. Plasma glucagon responses to arginine were greater (P < 0.05) for lactating cows than for growing calves. The insulin:glucagon molar ratio increased in response to the metabolite injections except following injections of arginine and propionate into lactating cows, when the ratio did not increase significantly. It is possible that in cows the enhanced responsiveness of glucagon secretion plays a role in the maintenance of lactation. Key words: Insulin, glucagon, arginine, propionate, lactating cow, growing calf
Quality of deferred forage from waterfowl nesting sites on the Canadian prairies
Authors: Jefferson Paul G. , Wetter Les , Wark Brent
Published: March 2010

The nesting success of waterfowl can be increased by deferred use of perennial forage plant species adjacent to Canadian prairie wetlands for habitat cover. However, the maintenance of plant species diversity and biomass production requires periodic vegetation management such as biomass harvesting. The objective of this study was to determine the quality of forage harvested from these sites as affected by deferral period (years), cutting height, species type (tame vs. native) and province. Biomass was sampled at 16, 12 and 12 sites in Manitoba, Saskatchewan, and Alberta, respectively, representing a range from 2 to 4 yr of deferred use. Plant species were described and samples were clipped at 10 and 20 cm cutting height at 8 or 16 transect points per site in late July or early August 1994. Forage quality was determined as crude protein (CP), in vitro organic matter digestibility (IVOMD), acid detergent fibre (ADF), neutral detergent fibre (NDF), P and Ca content. Deferral period affected quality, but the response varied by province. For example, IVOMD was 90 g kg−1 higher at sites with longer deferred use in Saskatchewan, but was similar for Alberta and Manitoba sites. Harvesting at 20 cm height resulted in 24 g kg−1 greater IVOMD and 9 g kg−1 increased CP averaged across all three provinces. Forage from tame species sites exhibited 70 g kg−1 higher IVOMD, 49 g kg−1 greater CP, 0.3 g kg−1 more P and 4.6 g kg−1 more Ca content than that of native species sites in Alberta but there was no difference between vegetation types at sites in the other provinces. These forage sources will produce medium quality hay for beef cattle production. Deferring native species sites for 2 yr will produce highest biomass yields with the highest cellulosic content for potential bioethanol conversion. Key words: Conservation, biomass, forage quality, NDF, ADF, protein, cellulose, hemicellulose, P, Ca
The effect of calcium on mammary epithelial cell proliferation and the plasminogen activating system
Authors: Cheli F. , Zavizion B. , Todoulou O. , Politis I.
Published: March 2010

The objectives of this study were to examine 1) the effect of extracellular calcium on proliferation of bovine mammary epithelial cells, 2) whether extracellular calcium regulates the mitogenic effect of insulin-like growth factor (IGF-I) and epidermal growth factor (EGF) towards mammary epithelial cells, and 3) whether the effects of calcium on growth are mediated through changes in the plasminogen activating system. The BME-UV1 cells were used as a model system. Results showed that optimal proliferation of BME-UV1 cells grown in the presence of 10% dialyzed FBCS was achieved when the culture medium was supplemented with 1–2 mmol L−1 of extracellular Ca2+. IGF-I (P<0.01) but not EGF, increased proliferation of BME-UV1 cells. Furthermore, calcium does not regulate IGF-I and EGF responsiveness of BME-UV1 cells. Northern blot analysis was performed to examine the effect of extracellular calcium on expression of urokinase-type plasminogen activator (u-PA), PA inhibitor 1 (PAI-1) and u-PA receptor (u-PAR) genes by BME-UV1 cells in culture. Results showed that calcium increased expression of all above-mentioned genes after 24 h of exposure of cells to calcium, at a time that the effect of calcium on growth was not apparent. Calcium had no effect on u-PA and u-PAR expression after 48 and 72 h of exposure of cells to calcium, at a time that the effect of calcium on growth was predominant. Calcium caused a small increase of PAI-1 expression after 48 and 72 h but this small increase is apparently of limited biological value. Key words: Mammary epithelial cells, calcium, growth factors, plasminogen activating system
Use of the Cornell Net Carbohydrate and Protein System and rumen-protected methionine to maintain milk production in cows receiving reduced protein diets
Authors: von Keyserlingk Marina A. G. , Swift Mary Lou , Shelford J. A.
Published: March 2010

Twenty-two primiparous and forty-eight multiparous lactating Holstein cows were used in a production trial. Cowswere randomly assigned to two treatments to assess the effects of formulating a lower crude protein (CP) diet using the Cornell Net Carbohydrate and Protein Model (CNCPS), which included rumen-protected methionine and a bypass protein on group feed intake, milk yield, milk composition and blood urea nitrogen (BUN) status. Those animals receiving the lower CP diet were able to maintain milk production (P > 0.05) and milk component yield (P > 0.05) when compared with the animals receiving the control diet. Although no statistical analysis could be undertaken on the dry matter intake data, due to insufficient degrees of freedom, group intakes appeared to be similar. Multiparous cows were also observed with the cows receiving the diet supplemented with bypass methionine and bypass protein had significantly lower BUN levels when compared with the control cows. These results indicate that the CNCPS model can be used as a tool for formulating lower CP diets since cows receiving the bypass methionine and bypass protein were able to maintain milk production. Key words: Dairy cattle, milk yield, bypass methionine, bypass protein, Cornell Net Carbohydrate and Protein System
Prediction of composition and ruminal degradability characteristics of barley straw by near infrared reflectance spectroscopy
Authors: Mathison G. W. , Hsu H. , Soofi-Siawash R. , Recinos-Diaz G. , Okine E. K. , Helm J. , Juskiw P.
Published: March 2010

The usefulness of near infrared reflectance spectroscopy (NIRS) for the prediction of the nutritive value of straw was examined with 195 samples of barley straw. Excluding lignin, NIRS technique explained 84 to 94% of the variation in chemical components in the validation set. From 69 to 84% of the variation in ruminal degradability characteristics, excluding rate of degradation, was explained by NIRS. With the exception of neutral detergent fiber, accuracies of prediction were not improved when NIRS calibrations were based upon calibration sets containing straw only in contrast with when barley hay and barley silage were included with straw in the calibration set. We conclude that near infrared reflectance spectroscopy is a useful method for predicting chemical composition of straw and estimating its ruminal degradability characteristics. Key words: Barley, straw, near infrared reflectance spectroscopy, in situ, degradability
Factors influencing composition and ruminal degradability of barley straw
Authors: Mathison G. W. , Soofi-Siawash R. , Okine E. K. , Helm J. , Juskiw P.
Published: March 2010

Chemical composition and in situ ruminal degradability characteristics for 25 and 40 genotypes of barley straw were measured for crops grown in 1994 and 1995, respectively. Straw from semidwarf genotypes contained more crude protein and less neutral detergent fiber (NDF) than that from genotypes with medium straw length and effective ruminal degradability was 9% higher (P < 0.01). Straw from two-row genotypes contained 19% more crude protein (4.4 vs. 3.7%) and 3% less NDF (75.2 vs. 77.6%) than that from six-row genotypes and effective ruminal degradability was 6% higher (P < 0.01) when genotypes with medium-length straw only were considered. Genotypes with smooth awns had higher rates of degradation but contained less of the slowly degraded fraction than straw with rough awns when straws of medium straw length were compared (P < 0.05). Straw from hulless genotypes contained more (P = 0.006) NDF than that from covered varieties. Both ambient and soil temperature were positively related (P < 0.05) to effective ruminal degradability of straw, possibly because of associated greater leafiness when temperatures were higher and there was more light. It was concluded that it is possible to select barley genotypes that have superior straw nutritive value for ruminant animals. Key words: Barley, straw, degradability, cattle, genotype, environment
Analysis of volatile fatty acids in rumen fluid by proton NMR spectroscopy
Authors: Attaelmannan M. A. , Dahl A. A. , Reid R. S.
Published: March 2010

A study was conducted to quantify the volatile fatty acid (VFA) concentrations in aqueous and rumen fluid samples using a standard additions based quantitative proton nuclear magnetic resonance (NMR) spectroscopic method. Standard plots for acetic, propionic and butyric acids were all found to be linear (R2 > 0.99). Results obtained by NMR were compared with those obtained using the conventional gas chromatographic method. No significant differences were found between the means and precisions of the two techniques (P < 0.05). The method is well-suited for the routine quantification of these acids, requires no sample pretreatment and is more rapid than gas chromatography. Key words: Volatile fatty acid determination, rumen fluid, gas chromatography, nuclear magnetic resonance spectroscopy
Comparative characteristics during wilting for alfalfa conditioned by maceration or by a conventional roller-conditioner
Authors: Suwarno Suwarno , Wittenberg K. M. , McCaughey W. P.
Published: March 2010

A study was conducted to monitor nutrient and microbial count changes during wilting of alfalfa (Medicago sativa L.) in response to varying degrees of maceration at mowing. Early bloom alfalfa was mowed with either a roller-conditioner (CONV) or a macerator set to deliver four degrees of maceration during alfalfa mowing: LIGHT, LIGHT+, SEVERE, and SEVERE+. Macerated alfalfa reached 80% dry matter in 9–11 h compared with alfalfa mowed by roller-conditioner, which required 54 h. The most rapid wilting rates were associated with LIGHT+, SEVERE, and SEVERE+ maceration treatments when alfalfa was not exposed to precipitation. The wilting coefficient in the first 24 h was increased by more than 100% for the SEVERE treatment compared with alfalfa mowed using a conventional roller-conditioner in alfalfa that was not exposed to precipitation. Precipitation at 1.5 h post-mowing increased wilting time by 8.3 h to achieve 45% DM, and by 17.5 to achieve 80% DM in the SEVERE+ maceration treatment relative to alfalfa from the same conditioning treatment that was not exposed to precipitation. Precipitation at 24 h post-mowing increased wilting time to reach 80% DM by 11 h and 21 h for the LIGHT and LIGHT+ maceration treatments relative to alfalfa of the same mowing treatments not exposed to precipitation. Maceration of alfalfa resulted in a 24.2 to 26.8 h shorter wilting time relative to the conventional roller-conditioner treatment when alfalfa was exposed to precipitation at 24 h post-mowing. SEVERE and SEVERE+ maceration treatments at mowing resulted in higher (P < 0.05) neutral detergent fibre and acid detergent fibre levels post-wilting. Lactic acid bacteria populations on alfalfa tended to be higher with maceration within 1 h post-mowing (P < 0.10) and post-wilting (P < 0.08). Key words: Alfalfa, maceration, precipitation, wilting time, bacteria, nutrient profile, compressibility
Application of a dynamic simulation model on the effects of calving season and weaning age on bioeconomic efficiency
Authors: Pang H. , Makarechian M. , Basarab J. A. , Berg R. T.
Published: March 2010

A dynamic simulation model, Alberta Beef Production Simulation System (ABPSS), which includes herd inventory, nutrient requirements, forage production, and economic submodels, was used to compare bioeconomic efficiency in spring and fall calvings and different weaning ages (220, 200, 180, 160, and 140 d). Comparisons were made assuming a mature cow weight of 550 kg and a peak milk yield of 8.2 kg d−1. The first day of calving was assumed to be 28 March and 8 September for spring- and fall-calving cows, respectively. Bioeconomic efficiency was measured as the net return per cow (total return minus total cost). Fall calving in Alberta generally results in longer exposure of young calves to extreme cold weather after calving, and therefore total annual DMI and feed cost were higher in the fall-calving season group than in the spring-calving season group. Bioeconomic efficiency improved as weaning age increased from 140 to 220 d in both calving seasons. For weaning age of 200 d or less, spring calving was more efficient than fall calving. However, at a weaning age of 220 d, fall calving had higher bioeconomic efficiency than spring calving, primarily due to higher market prices for fall-born calves. This indicated that interactions of calving season by weaning age was an important factor affecting bioeconomic efficiency. It must be noted that the model was developed based on experimental results and data from the liteature, and due to the unavailability of suitable data the model could not be validated. We suggest that the ABPSS model has the potential for providing a useful decision-making tool for simultaneous consideration of many factors in an integrated system and for evaluating the effects of alternative management strategies on profitability of beef production systems. Key words: Beef cattle, simulation and modelling, production system, calving season, weaning age, bioeconomic efficiency
Soaking and pelleting of pig diets alters the apparent absorption and retention of minerals
Authors: Larsen Torben , Skoglund Erika , Sandberg Ann-Sofie , Engberg Ricarda M.
Published: March 2010

The effect of soaking a pig's diet in water (9 h at room temperature) or heat pelleting (81 °C) on apparent absorption and retention of intrinsic minerals was studied with and without the addition of calcium carbonate in a 2 × 3 factorial design. Thirty pigs were allocated to different diet treatments and two separate balances were calculated throughout a 33-d study. Soaking the diet significantly (P < 0.001) reduced the phytate content (IP6) and increased (P < 0.001) the fractional content of degradation products (IP3-5), whereas heat pelleting only marginally affected these compounds. Soaking and heat pelleting of feeds did not affect dry matter (DM) digestibility or N and S balances in the animals (P > 0.05), indicating that feed matrix remained unaltered by the treatments. Dietary Ca addition reduced the absorption coefficient of DM (P < 0.01), ash (P < 0.001) and Ca (P < 0.05) as well as the uptake of P (P < 0.001). Heat pelleting selectively reduced the uptake of feed Ca, Fe, Zn, Cu, and Mn compared with untreated and soaked diets (P < 0.05). In conclusion, heat pelleting of feeds showed a negative effect on mineral uptake, whereas the soaking procedure seemed to have only a very marginal positive (P > 0.05) effect on the uptake of elements in the digestive tract. Key words: Heat pelleting, soaking, inositol phosphates, phytate, calcium, trace elements
Liver metabolic activities of intact male pigs injected with skatole
Authors: Babol J. , Squires E. J.
Published: March 2010

Twelve intact male pigs (101.3 ± 1.8 kg liveweight [LW]) were divided into two groups, with six pigs receiving nine daily i.m. injections of skatole (1 mg kg−1 LW). Enzymatic activities were measured in liver tissues taken at slaughter. These included the rate of phase I skatole metabolism and the rate of glucuronidation and sulphation of 2-naphthol and(or) p-nitrophenol. Fat skatole concentration was higher (P = 0.001) in pigs injected with skatole (0.41 ± 0.04 ppm) than in control pigs (0.10 ± 0.04 ppm); however, enzymatic activities did not differ between the treatments. The results indicate that increased levels of skatole in backfat do not affect the enzymatic activities involved in skatole metabolism in the liver. Key words: Pigs, skatole, indole, boar taint, liver metabolism
Effects of maturity of silage and protein content of concentrates on milk production of ewes rearing twin or triplet lambs
Authors: Roy A. , Laforest J. P. , Castonguay F. , Brisson G. J.
Published: March 2010

Fifty-one Outaouais Arcott ewes were used to study the effects of silage maturity, protein level and number of lambs suckled on milk production and lamb growth in a 2 × 2 × 2 factorial design experiment. Ewes were given ad libitum access to either an early-bloom (EB) or full-bloom (FB) bromegrass silage supplemented with 725 g d−1 of a 15 or 21% CP concentrate. Number of lambs suckled were two or three per ewe. During the 6 wk of lactation, ewes receiving the EB silages consumed more DM (2.07 vs. 1.74 kg d−1, P < 0.01), and gained more (1.3 and −2.7 kg, P < 0.05) than ewes fed FB. Ewes that raised three lambs had greater silage intake (2.00 vs 1.86 kg d−1) and lost more weight during lactation (−2.8 vs. +0.3 kg) than those suckling twins. Milk yields of ewes offered the EB and FB silages were 2.42 and 2.28 kg d−1, respectively (P < 0.05), for the first 4 wk of lactation. Ewes that raised three lambs produced less milk (2.25 vs. 2.43 kg d−1) than those nursing twins (P < 0.05). Milk fat content (8.2%) was not influenced by treatments, whereas milk protein content was higher (P < 0.05) from ewes receiving the EB silage compared with the FB silage (5.05 vs. 4.76%). At 4 and 6 wk of age, twin lambs were 2.6 kg (9.5 vs. 6.9 kg) and 3.5 kg (12.0 vs. 8.5 kg) heavier (P < 0.01) than triplet lambs for EB and FB silages, respectively. However, at the end of the 6-wk period, ewes nursing triplets weaned 1.3 kg more lambs than did ewes nursing twins (P < 0.05). Lambs from ewes that received the EB silage were 1.1 kg heavier at 6 wk (P < 0.05) than those from ewes fed with the FB silage. Also, lambs from ewes receiving the 21% CP concentrate were 1.1 kg heavier at 6 wk (P < 0.05) than the lambs from ewes fed the 15% CP. Litters were heavier at 6 wk with 21% CP concentrate compared with 15% (25.1 vs. 24.1 kg, P < 0.05), and triplet litters were heavier (P < 0.01) than twin with the EB silage. Within litter weight variation (weight difference between the biggest and the smallest lambs in a litter) proved to be greater (P < 0.05) with triplets (4.2 kg) than twins (2.2 kg). In conclusion, providing a higher quality silage (lower ADF and higher CP contents) improved ewe feed intake, milk production, lamb growth and litter weight, while feeding a higher protein concentrate only improved lamb growth with the lower quality silage. Key words: Ewe, lamb, growth, milk production, silage, protein, triplet
Neural network modeling of carcass measurements to predict beef tenderness
Authors: Hill B. D. , Jones S. D. M. , Robertson W. M. , Major I. T.
Published: March 2010

Neural network (NN) models were developed for predicting and classifying an objective measurement of tenderness using carcass data such as pre-slaughter information (sex, age, kill order), weights, pH, temperatures, lean color readings, lab-determined measurements, grade measurements and organ weights. Tenderness was expressed objectively as Warner-Bratzler shear (WBS) force measured on steaks, aged 6 d, from the longissimus thoracis et lumborum (LTL) muscle. Carcass data from experiments conducted between 1985 and 1995 at the Lacombe Research Centre were combined to form large data sets (n = 775–1177) for modeling. Neural network models to predict actual shear values showed limited potential (R2 = 0.37–0.45) and were only marginally better than a multiple linear regression (MLR) model (R2 = 0.34). Neural network models that classified carcasses into tenderness categories showed better potential (mean accuracy 51–53%). The best four-category (tender, probably tender, probably tough, tough) model classified tender and tough steaks with accuracies of 0.64 and 0.79, respectively. This model reduced tough and probably tough carcasses by 55% in our population. The model required the following 11 inputs, which, except for cooking method, are available by 24 h postmortem: sex, live plant weight, hot carcass weight, 24-h cooler shrink, 24-h pH, 24-h CIE color b*, 24-h CIE lightness L* × hue angle, rib eye area, grader's marbling score (AMSA%), grade, and cooking method. By implementing techniques outlined in this study in a plant situation, the current 23% unacceptable consumer rating for Canadian beef could be reduced to 10–12%. Key words: Neural networks, beef, tenderness, carcass measurements, longissimus muscle
Effects of variations in dietary protein levels on hair growth and pelt quality in mink (Mustela vison)
Authors: Rasmussen Palle V. , Børsting Christian F.
Published: March 2010

The effect of different and shifting dietary protein levels on hair growth and the resulting pelt quality in mink was studied. Two groups of pastel female mink were fed either 59% (high protein, HP) or 40% (low protein, LP) of metabolisable energy (ME) from protein during pregnancy and lactation. Shortly after weaning, kits from females fed the LP diet were put on a new LP diet (21% protein of ME). Kits from females fed HP were randomly distributed to four experimental groups fed a new HP diet (34% protein of ME) and three of these groups were shifted to diets with 21% protein at different times during June until September. Skin biopsies were taken at 4, 6, 23 and, 29 wk of age. Histological techniques and computer-assisted light microscopy were used to determine the ratio of activity (ROA) of underfur and guard hairs, respectively, defined as the number of growing hairs as a percentage of the total number of hairs. The hair fibre length and thickness were determined by morphometric methods and correlated with fur properties of dried pelts judged by sensory methods. It was documented that 40% of ME from protein during pregnancy and lactation was sufficient for mink kits to express their genetic capacity to produce hair follicles. In males, a reduced protein level from the age of 15 wk or 22 wk until pelting disturbed moulting, indicated by a low ROA of underfur hairs at 23 wk, and consequently reduced the growth and development of the winter coat. A constantly low protein level from conception until the age of 29 wk did not disturb moulting, but led to a reduction of primeness and especially of the underfur length and fibre thickness of the winter coat. A low protein level from the age of 9 wk only reduced the thickness of the underfur fibres. Hair growth, final fur volume, and general quality of the winter coat of males were influenced negatively and to the same degree in all groups fed the LP diet in part of the growth period. The number of underfur hairs per area (hair density) of the winter coat was not influenced by the dietary treatment meaning that the protein content of 21% of ME in the LP diet was high enough for the mink to express its genetic capacity to develop hair follicles. However, this low protein content led to a reduction of hair fibre length and hair fibre thickness of the underfur. Overall, this study demonstrated that hair growth and hair properties in pelts are very dependent on the dietary protein supply in the period from 22 wk of age until pelting, irrespective of the supply in the preceding periods. Key words: Fur properties, hair fibres, nutrition, pelage, protein requirement
Replacement of soybean meal with roasted full-fat soybeans from high-protein or conventional cultivars in diets for broiler chickens
Authors: Hamilton Robert M. G. , McNiven M. A.
Published: March 2010

The effects were examined of replacing part or all of the soybean meal in the starter and finisher diets for male broiler chickens with ground, roasted, full-fat soybeans from either a high-protein (AC Proteus) or conventional (Baron) cultivar. The starter (1–21 d) and finisher (22–36 d) diets were formulated by replacing, on an isonitrogenous basis, part or all of the soybean meal in the barley–wheat-based control diets with the roasted soybeans. Digestibility of dry matter, corrected nitrogen and energy were estimated by an index method for the last 2 d of the starter and grower periods. Soybean level influenced body weight gains directly in a quadratic manner, and feed intakes or feed conversions by inversely linear relationships (P < 0.05 and P < 0.01) during the starter period. Performance during the finisher period or during the entire growth period was not influenced (P > 0.05) by dietary soybean source. Dry matter and energy digestibilities at both 21 and 35 d, and nitrogen at 35 d were affected in a quadratic manner (P < 0.05 or P < 0.01) by the soybean level of the diets, whereas, a linear relationship was present for the apparent metabolizable energy (AME) content (P < 0.001). Soybean source had no effect on nutrient utilization, except for dry matter or energy digestibility during the starter period (P < 0.01). In conclusion, the optimal performance should be obtained when the ratio of roasted full-fat soybeans to soybean meal is about 2:1 in the starter feeds for broiler chickens. Key words: Full-fat soybeans, soybean meal, high-protein soybeans, broiler, growth, nutrient digestibilities
Effect of vasoactive intestinal polypeptide and environmental temperature on forestomach electromyographic activity and gastrointestinal contraction in sheep
Authors: Li B. T. , Okine E. K. , Christopherson R. J.
Published: March 2010

Four crossover design experiments were conducted with sheep to test the hypothesis that vasoactive intestinal polypeptide (VIP) affects gastrointestinal motility with implications for digesta flow. Sheep were shorn and surgically prepared with electrodes implanted on the forestomach, cannulae in the rumen, duodenum or/and ilieum, and a left gastric artery catheter. VIP (1 or 1.5 nmol min−1) or saline (control) was infused for 10 min at half-hour or hour intervals for 4 or 7 d during treatment periods. VIP transiently inhibited electromyographic (EMG) activity of the reticulum, reticulo-omasal orifice (ROO) and omasum for 3 to 8 min during the 10-min infusion periods. VIP infusion extended the duration of ROO opening (P < 0.01). The gastrointestinal lumen pressure pattern was also transiently influenced by VIP, with an increase of quiescent time. Cold exposure of sheep stimulated a relatively higher motility in the ROO and omasum. The results indicate that the inhibitory effect of VIP on the reticulum, ROO and omasum electrical activity is transient; however, its action to extend the duration of opening of the ROO may facilitate digesta passage. Key words: Sheep, vasoactive intestinal polypeptide, electromyographic activity, reticulo-omasal orifice
Influence of sire line and halothane genotype on growth performance, carcass characteristics, and meat quality in pigs
Authors: Miller K. D. , Ellis M. , McKeith F. K. , Wilson E. R.
Published: March 2010

Progeny of three commercial sire lines mated to the same halothane negative crossbreed dam line were compared for growth, carcass and meat quality characteristics. Sire line A (halothane reactor) produced halothane carrier progeny; line C was halothane negative and produced negative progeny; line B (a cross between lines A and C) was a halothane carrier line that produced both carrier (BNn) and negative (BNN) progeny within the same litter. Line A pigs grew more slowly (P ≤ 0.05) and consumed less feed (P ≤ 0.05) than the progeny of the other lines (885, 1049, 1057 and 1082 g d−1 and 2.37, 2.82, 2.72 and 2.79 kg d−1 for lines a, BNN, BNn and C respectively). However, gain:feed was similar for all lines. Dressing percentage was similar for lines A, BNn and BNN (77.42, 77.62 and 77.00% respectively) but lower for line C (75.31%: P ≤ 0.05). Line differences for linear carcass measurements, lean cut yield and fat-free lean content were relatively small. Line A had higher shear force than the others (4.32, 3.21, 3.57, and 3.30 kg for A, BNN, BNn and C, respectively; P ≤ 0.05) and lines A and BNn had reduced taste panel tenderness and juiciness (P ≤ 0.05) compared with lines BNN and C. This study highlights commercially important differences between sire lines for pork quality traits. the variation in pork quality within this study resulted from the halothane gene and, potentially, other single genes that affect meat quality parameters. Key words: halothane gene, meat quality, sire line, pigs, carcass quality
Ileal digestibility of protein and amino acids of feed peas with different trypsin inhibitor activity in pigs
Authors: Grosjean F. , Jondreville C. , Williatte-Hazouard I. , Skiba F. , Carrouée B. , Gâtel F.
Published: March 2010

Ileal digestibility of protein and amino acids was measured in pigs fed 13 round, tannin-free peas samples and related to the following physical, chemical and biological characteristics of these samples: thousand-seed weight, proportion of hulls, starch, fibre, crude protein, ether extract and ash contents, trypsin inhibitor activity and trypsin inhibitor activity per unit of crude protein (TIAP). Each pea sample was included in a diet containing starch, sucrose, minerals and vitamins and fed to four barrows (50 to 100 kg) fitted with an end-to-end ileo-rectal anastomosis. Standardised ileal protein and amino acid digestibilities, except for alanine of peas decreased linearly with increasing TIAP (P < 0.01) and was not affected by fiber content. For example standardized ileal digestibilities values (%) decreased by −0.1975, −0.1617, −0.2171, −0.2630, −0.2029 and −0.3536 per unit of TIAP (expressed in unit of trypsin inhibited per milligram crude protein), respectively, for crude protein and lysine, threonine, methionine, cystine and tryptophan. Key words: Peas, trypsin inhibitor activity, standardised ileal digestibilities, protein, amino acids, pig
Isolation and culture of wapiti (Cervus elaphus) satellite cells
Authors: Burton N.M. , Shipley L. , Byrne K. M. , Vierck J. L. , Dodson M. V.
Published: March 2010

Myogenic satellite cells (SC) were isolated from the sternomandibularis muscles of two, 227 kg, male wapiti (Cervus elaphus) and studied in primary cell culture. Wapiti-derived SC were capable of attaching to culture substrata and following the myogenic program of proliferation and differentiation to form multinucleated myotubes. Wapiti SC attached equally well to pig skin gelatin (PSG), fibronectin (FN), Matrigel® and plastic (P > 00.05), but cell viability measured at 120 h varied depending on initial substratum type. Pig skin gelatin (0.02% wt vol−1) was chosen for the majority of subsequent experimentation for cost efficiency. The greatest amount of wapiti SC proliferation was observed in media containing 10% (vol/vol−1) horse serum (HS), 15% HS and 15% fetal bovine serum (FBS) (P > 0.05). Wapiti SC proliferated more when exposed to HS and FBS than to sheep serum (SS) (P < 0.05). No proliferation, differentiation or decrease in cell viability was observed in Dulbecco's Modified Eagle Medium (DMEM) + 1% HS, DMEM + 2% HS, DMEM + 3% HS or DMEM + 4% HS (P > 0.05) after 120 h in vitro. Proliferation of SC was doubled when insulin was added to both 10% HS- and 2% HS-containing media (P < 0.05). Although insulin alone in serum-containing media did not promote fusion of wapiti SC, two defined media (ITT and ITT-CF) that contain insulin did promote fusion of wapiti SC cultures. ITT-CF induced 3% fusion of wapiti SC into myotubes, and ITT induced 1% (P < 0.05). There was also an increase in total cell numbers in SC exposed to ITT-CF in comparison with ITT, ovine defined media (ODM) or ovine defined media-Modified (ODM-Mod))(P < 0.05). Although defined media differed in their ability to induce proliferation or differentiation (P < 0.05), the substrata on which the SC were plated did not influence the defined media effect on SC activity (P > 0.05). Satellite cells exposed to ITT and ITT-CF differed morphologically from SC exposed to ODM and ODM-Mod, which may suggest that formulation differences are influencing wapiti-derived SC proliferation and differentiation. Key words: Wapiti, satellite cells, primary culture, myotubes
Comparison of one-quarter Chinese Meishan and three-breed conventional cross females for sow productivity, and growth and carcass characteristics of the progeny
Authors: Wolter B. F. , Hamilton D. N. , Ellis M.
Published: March 2010

The reproductive performance over five parities of two one-quarter Meishan female genotypes were compared with a three-breed cross female genotype based on conventional breeds of pigs. Hampshire-sired progeny from these females were evaluated for growth performance and carcass measures. The female genotypes evaluated were Landrace × (Meishan × Yorkshire) (LMeY) (n = 45), Duroc × (Meishan × Yorkshire) (DMeY) (n = 41), and Landrace × (Duroc × Yorkshire) (LDY) (n = 50), respectively. LMeY had a greater number of pigs born alive (11.1, 10.6, and 10.2, SE = 0.24 for LMeY, DMeY, and LDY, respectively, P < 0.05) and a higher total litter birth weight (20.02, 18.16, and 17.29, SE = 0.383 kg for LMeY, DMeY, and LDY, respectively, P < 0.001) than the other lines. Gestation length was reduced for the two Meishan-cross genotypes (114.5, 114.3, and 114.9, SE = 0.18, for LMeY, DMeY and LDY, respectively; P < 0.001). A shorter farrowing interval was observed for the LMeY (147.1, 148.6 and 151.4, SE = 1.32 for LMeY, DMeY and LDY, respectively, P < 0.05). Number of pigs weaned per litter was highest for LMeY line (10.7, 10.0, and 9.4, SE = 0.22 for LMeY, DMeY and LDY, respectively; P < 0.05). No differences (P > 0.05) were observed between the Hampshire-sired progeny of the three dam genotypes for growth performance, backfat thickness and loin eye depth at 114 kg. These results indicate that the development of a female line with one-quarter Meishan may result in improved reproductive efficiency compared to female lines based on western breeds. Key words: Pigs, crossbred, Meishan, reproductive performance, growth performance
Is there a lifeguard at the genepool?
Authors: Patterson Dian L.
Published: March 2010

Modern agricultural practices have led to a decline in our farm animal genetic resources. Changes in the environment or society demands for more ecologically sustainable production systems may require breeds other than those in common use today. Although definitions of levels of concern differ, Canada has a number of endangered breeds which are of cultural and historical interest and which may be useful in future niche markets. Canada has formally ratified the international convention on biological diversity, but funding cuts have jeopardised national programs. The Food and Agriculture Organisation of the United Nations has the mandate to establish an international program for conserving domestic animal diversity and its sustainable use. A major initiative has been the establishment of a data base and training information available through the World Wide Web. New technologies such as microsatellite markers and mathematical modelling offer promise for integration with more traditional live animal conservation methods and are now being incorporated into conservation schemes in a number of countries. Canadian groups involved in livestock and poultry genetic resource conservation must continue to interact to ensure a coordinated approach. Key words: Biodiversity, breed conservation, animal genetic resources
World population growth, distribution and demographics and their implications on food production
Authors: McQueen R. E.
Published: March 2010

The world's human population of 6 billion is currently projected by the United Nations to reach about 8 billion by the year 2025 and continue growing until stabilising at about 10.8 billion in 2150. Most of this increase is destined to occur in underdeveloped countries. It is not only the magnitude of this population growth, but also its speed that will cause unprecedented strain on world food production. It will also affect living standards in most countries and likely widen the disparities that exist between the industrialised and underdeveloped nations. While world food production currently exceeds requirements, economic and political constraints on its distribution leave about 800 million people malnourished. Food production, processing and distribution in the industrialised countries rely heavily on energy provided by petroleum products. As global oil production is expected to begin declining within 5 yr, alternative energy strategies will be required. Human activities are also being linked to changes in global weather, and to the destruction of the soil and water resources necessary for sustainable food production. The scale and rapidity of these changes in turn will affect the productivity and stability of agriculture systems in the world's major food producing areas. As societies react to these pressures on food production, choices between economic and humanistic goals will become more prominent political issues. Key words: World population, demographics, food production
Effects of beta-adrenergic receptor agonist and low environmental temperature on the immune system of growing lambs
Authors: Li Y. Z. , Christopherson R. J. , Field C. J.
Published: March 2010

Sixteen lambs were studied to examine the effects of cold environment and a beta-agonist on their immune status. The beta-agonist, L-646, 969, was fed for 4 wk at 0.28 or 0 mg kg−0.75 BW to animals housed in a warm (20 °C) or a moderately cold (0 °C) environment. The cold environment suppressed PWM-stimulated proliferation at week 3 (P < 0.03) and week 4 (P < 0.01). The percentage of CD4 cells and CD4:CD8 cell ratio were decreased at week 1 (P < 0.02; P < 0.05) and week 3 (P < 0.001; P < 0.003), and the percentage of CD2 cells (P < 0.05) was decreased at week 2 at the low-temperature. The beta-agonist did not influence leukocyte profile and lymphocyte functions. The results suggest that a cold environment may influence immune function by suppressing lymphocytes expressing CD2, CD4 and CD4:CD8 cell ratio, and changing lymphocyte proliferative response to a T cell mitogen. Further investigation is required to identify the effects of prolonged and intense cold exposure on the immune system with a large number of animals and the implications of current observations for the health of animals in a cold environment. Key words: Immunity, cold environment, beta-agonist, lambs
Effectiveness of norgestomet implants in suppressing ovulation and estrus in heifers varies with stage of estrous cycle when implanted
Authors: Yavas Y. , Avila D. M. de , Reeves J. J.
Published: March 2010

Suppression of ovulation and estrus for 63 d by a 24-mg norgestomet ear implant with a delivery rate of 160 µ g d−1 was evaluated in beef heifers. Ovulation was suppressed in 80% of heifers implanted on day 7 of the estrous cycle, 40% on day 10, 33% on day 13, 53% on day 16, and 67% on day 19 (P < 0.05 for day 7 vs. days 10, 13 and 16). The norgestomet implant was more effective in suppressing ovulation and estrus when inserted on day 7 of the estrous cycle rather than later in the cycle. Key words: Norgestomet, progestogen, ovulation, estrus, heifer
Growth and differentiation of cultured satellite cells from callipyge and normal lambs
Authors: Carpenter C. E. , Rodriguez B. T. , Cockett N. E.
Published: March 2010

We tested whether the muscle enlargement found in callipyge sheep is linked to increased proliferation, differentiation, and protein accrual of cultured satellite cells. Satellite cells were isolated from the longissimus muscle of three callipyge and three normal lambs. The satellite cells were grown using serum from horse, normal lambs, and callipyge lambs and cultured under conditions that promoted differentiation into myotubes and accumulation of myofibrillar protein. There was no difference in the population doubling times (PDT) or fusion percentages for callipyge and normal satellite cells, but PDT was longer (P < 0.05) for satellite cells grown in callipyge serum (pooled mean PDT = 22 h) than for cells grown in normal sheep serum (PDT = 20 h) or horse serum (PDT = 18 h). The protein:DNA ratios of the cultures increased during 96 h in differentiation media (P < 0.01), but there was no difference in protein:DNA ratios between cells from callipyge and normal lambs. These results suggest that muscle hypertrophy of callipyge sheep is not linked to the inherent capacity of their cultured satellite cells to proliferate, fuse or accrue protein, but hypertrophy may be linked to the influence of serum-born factors on satellite cell proliferation. Key words: Satellite cell, callipyge, sheep, cell culture