bluuebunny/crossref_metadata_2025 huggingface dataset:
Enzyme applications for monogastric feeds: A review
Authors: Campbell G. L. , Bedford M. R.
Published: March 2010

The potential for industrial enzyme products as animal feed additives has attracted substantial interest from feed manufacturers as a novel means of improving animal performance. Enzyme manufacturers have also targeted feed as an alternate outlet for their products, which have primarily been in the food, beverage, and detergent industries. Despite a history dating back 35 years or more, only recently has enzyme application been extensive and efforts in research intensified. The use of enzymes that degrade polysaccharides of the endosperm cell wall has become most prominent. The major cell wall polysaccharides are the β-glucans in barley and oats and arabinoxylans (pentosans) in rye, wheat, and triticale. In barley and rye particularly, the cell wall carbohydrates are prone to solubilization. The major enzymes are endolytic and achieve their beneficial effects by removal of diffusion constraints that interfere with nutrient absorption. Although most nutrients are affected, fat malabsorption may be severe in chicks fed unsupplemented diets containing barley or rye. Young chicks give the greatest response to enzyme-induced viscosity reduction; the response is much less evident in older birds or in swine. In addition to carbohydrases, renewed research in dietary phytase has occurred with the realization that phytases provide a cost-effective alternative to inorganic phosphorous in regions with dense populations and intensive livestock production, where excessive phosphorus in animal wastes is a national concern. Other enzymes may also be beneficial, including supplementary α-amylase (in young animals) and oligosaccharidases for feeds high in oligosaccharides; however, this has not been shown conclusively. Enzymes with desired activity and stability characteristics for feed applications will continue to be developed. Future directions for enzyme research may also involve genetic manipulation of the substrate to facilitate more complete enzyme degradation, as in the case of the fiber components of rye. Key words: Dietary enzymes, β-glucanase, pentosanase, phytase, feed, β-glucan, pentosan, phytate
Selection indexes for production traits of Canadian dairy sires
Authors: Gibson J. P. , Graham N. , Burnside E. B.
Published: March 2010

It would be of benefit to the dairy industry to have sires evaluated for the net economic value of their genetic potential for milk-production traits. Economic weights and selection indexes were derived for a variety of production circumstances, taking into account all returns and costs of dairy production and allowing for the existence of quotas. A single index designed for the average farmer in Ontario under a multiple-component pricing system was highly efficient (>98% of maximum gains) for most situations. Changes in pricing of milk caused the largest changes in the index. An index based on the current volume payment with fat correction would cause a 24% loss in efficiency of selection if protein eventually becomes twice the price of fat. A single index was proposed as highly efficient for farmers across Canada irrespective of their production circumstances, provided payment for milk is based on a multiple-component pricing system giving roughly equal value to fat and protein and low value to milk volume. Key words: Selection indexes, economics, milk production, sire selection
Estimates of genetic parameters for growth and carcass traits in Charolais cattle
Authors: Johnston D. J. , Benyshek L. L. , Bertrand J. K. , Johnson M. H. , Weiss G. M.
Published: March 2010

Growth and carcass records were obtained on 1444 progeny, representing 53 Charolais sires from 7 yr of the Canadian Charolais Association Conception to Consumer Program. After weaning, all calves entered a commercial feedlot, where they remained on feed until they were visually appraised to grade A1 or A2, at which time they were slaughtered. The average age, backfat and carcass weight at slaughter were 417 d, 8.9 mm and 306 kg, respectively. Carcass weight, longissimus muscle area, marbling and number of days from on test to slaughter were adjusted to a fat constant end point of 8.9 mm of backfat. Genetic, phenotypic and environmental relationships were computed from variances and covariances estimated using a multiple-trait sire model with restricted maximum likelihood procedures between all pairwise combinations of growth and carcass traits. The following heritabilities were determined: birth weight, 0.25; 200-d adjusted weaning weight, 0.09; 365-d adjusted yearling weight, 0.16; feedlot test average daily gain, 0.19; relative growth rate, 0.18; number of days from on test to slaughter, 0.24; carcass weight, 0.09; longissimus muscle area, 0.38; and marbling score, 0.26. Carcass weight had a positive genetic correlation with longissimus muscle area (0.45) and number of days from on test to slaughter (0.29) but correlated negatively with marbling score (−0.31). Longissimus muscle area was negatively correlated with marbling score (−0.24). Key words: Beef cattle, growth and carcass traits, genetic parameters
The combined effects of time on feed, electrical stimulation and aging on beef quality
Authors: Aalhus J. L. , Jones S. D. M. , Tong A. K. W. , Jeremiah L. E. , Robertson W. M. , Gibson L. L.
Published: March 2010

Two experiments were conducted to determine the combined effects of time on feed, high-voltage electrical stimulation (HVES) and postmortem aging on beef quality and palatability. Increasing time on feed resulted in an increase in carcass fat thickness, dressed carcass weight and marbling and a decrease in carcass lean content, carcass shrinkage and shear values in both experiments. Steaks from longer-fed animals were rated more highly for juiciness, tenderness and overall palatability by the consumers polled. HVES lowered muscle pH (3, 24 and 144 h), increased subjectively appraised marbling fat, gave brighter, redder muscle colour up to 6 d postmortem, and improved consumer ratings for flavour, juiciness, tenderness and overall palatability. HVES also resulted in a significant improvement in shear values (shear values were decreased by 27 and 35% in experiments 1 and 2, respectively). Aging for 6 d improved meat colour, decreased the amount of expressible juice and lowered the shear value of steaks by 11 and 9% respectively, in experiments 1 and 2. A consumer survey indicated that more than 20% of steaks were rated as unacceptable for tenderness when time on feed and postmortem aging were similar to Canadian beef-production practices. Incorporation of HVES as a means of quality control would reduce the proportion of unacceptable steaks to approximately 10%. Key words: Beef quality, time on feed, electrical stimulation, aging
Effects of transport stress and electrolyte supplementation on body fluids and weights of bulls
Authors: Gortel K. , Young B. A. , Kawamoto S. C. , Schaefer A. L.
Published: March 2010

The effects of offering water (W) or an electrolyte solution (E) or neither (control; C) on the manifestation of transportation stress were examined in sixty-five 550-kg crossbred bulls. Following a 4-h (150-km) transport treatment serum electrolytes as well as live animal, carcass, and rumen content weights were monitored on all animals. In addition, intravenous injections of sodium thiocyanate and T-1824 dyes were used to examine extracellular (ECF) and plasma (PV) volumes in 10 (4 control, 3 water, and 3 electrolyte treatment) of the animals. The lowest carcass yield occurred in bulls denied access to both water and electrolytes during transport and the following (18 h) in lairage. Hot carcass yield (g kg−1 of final farm wt) for the C, E and W groups were 577.9 (57.8%) ± 3.8a, 597.5 (59.8%) ± 4.1b, and 589.4 (58.9%) ± 3.8b, respectively (P ≤ 0.05). The control (C) animals also had the lowest ECF volume (92.5, 127.9, and 142.3 liters for C, E and W, respectively). The effectiveness of water and electrolytes in reducing weight loss and improving carcass yield appeared to be explained to a large extent by the differential retention of fluid between the extra and intracellular body fluid compartments. Key words: Cattle, transport stress, electrolytes, fluid volumes
Carcass characteristics and tissue-mineral contents of steers fed supplemental chromium
Authors: Chang X. , Mowat D. N. , Spiers G. A.
Published: March 2010

This study investigated the effects of supplemental chromium (Cr) (0 or 0.2 mg kg−1 from high-Cr yeast) on performance, carcass characteristics and tissue-mineral contents of growing–finishing steers fed corn silage supplemented with either urea–corn or soybean meal during the growing period and a high-grain diet during the finishing period. Ninety-six Charolais-crossed steers, divided into four treatment groups with 24 animals each, were fed for a 70-d growing period followed by a 68-d finishing period. After continuous supplemental Cr, steers were commercially slaughtered and their carcass characteristics were evaluated. Tissue samples, including loin-eye lean and rib fat, liver and kidney, were analyzed for Cr and other minerals (P, Ca, Mg, Fe, Zn and Cu). Supplemental Cr had no effects (P > 0.05) on average daily gain (ADG), dry-matter intake, (DMI), feed efficiency (ADG/DMI), and carcass characteristics, including dressing percentage, loin-eye area, backfat thickness, marbling score, kidney fat and liver weight. Proportion of lean, fat and bone in rib sections was not affected (P > 0.05) by Cr supplementation. Supplemental Cr also did not affect (P > 0.05) total-tissue Cr and other mineral concentrations. However, supplemental Cr increased (P < 0.05) the Cu level of livers in steers fed urea–corn supplements during the growing period. This study showed that continuous supplementation of Cr (0.2 mg kg−1) to unstressed growing-finishing steers had no effect on carcass composition and several minerals in various tissues. Key words: Chromium, steer, carcass, tissue
Effect of environmental temperature, dietary energy, and feeding level on growth and carcass composition of male broiler chickens to 35 days of age
Authors: Perrault N. , Leeson S.
Published: March 2010

The effect of environment and nutrient intake on growth and development of commercial-strain broiler chicks, cage-reared to 35 days, was observed. Treatments involved high versus control dietary energy; ad libitum versus 80% of ad libitum intake; and cold control versus environment. Treatments were arranged as a 2 × 2 × 2 factorial, with each represented by 14 cages with eight birds per cage. Environmental temperature was maintained at 15.5 °C versus 23.9 °C from day 21 to day 35. Birds in the cold environment weighed less at 35 days, as did birds subjected to 20% feed restriction (P < 0.01). Dietary energy level had no effect on body weight, although birds fed the high-energy diet consumed more energy and less protein (P < 0.01). Whole-body analysis revealed more fat in birds in the control environment and in those fed the high-energy diet. Feeding level had no effect on body composition. Comparable effects were seen in analysis of breast, thigh and drumstick portions. Details of significant interactions between the three treatments are discussed. Data suggest that feed intake is less dependent on energy requirement and perhaps more closely related to physical satiety. Broilers consume more energy when fed a very high energy diet, presumably because of a desire to achieve a certain physical intake of feed. However, when there is an apparent need to consume more energy because of a cooler environment, no adjustment occurs. Key words; Temperature, energy, carcass composition
Procedure for analysis of phosphatidylcholine as a protozoal marker in ruminants
Authors: Neill L. , Dayrell M. de S. , Kramer J. K. G. , Ivan M.
Published: March 2010

A procedure was developed to analyze phosphatidylcholine in ruminal protozoa and duodenal digesta, for the estimation of the flow of protozoal constituents from the stomach to the small intestine of ruminant animals. The procedure requires 15–20 mg of dry ruminal protozoa and 50–60 mg of dry duodenal digesta. Key words: Phosphatidylcholine, protozoa, duodenal flow, ruminants
Sow preference for farrowing-crate width
Authors: Phillips P. A. , Fraser David , Thompson B. K.
Published: March 2010

A preference-testing apparatus was designed to provide sows with continuous access to three farrowing crates of different widths. The crates radiated from a central hub area sufficiently large for sows to enter or leave any crate freely. In exp. 1, nine sows were offered crates of 450-, 600- and 750-mm width at standing height. In exp. 2, 12 sows were offered widths of 450, 750 and 1200 mm, the largest being of sufficient width for the sow to turn around. Video recording was used to determine sow position from 3 d before to 6 d after farrowing. In exp. 1, sows showed a preference for the widest crate of 750 mm during and after farrowing (P < 0.05) but not before. In exp. 2, the 1200-mm width was preferred before, during and after farrowing (P < 0.005) over the widths that were too narrow to permit turning. Sufficient space for turning appears to be preferred by sows around the time of farrowing. Key words: Sow, farrowing crate, equipment design, preference testing, animal welfare
Comparison of nonlinear functions for describing the growth curve of three genotypes of dairy cattle
Authors: Perotto D. , Cue R. I. , Lee A. J.
Published: March 2010

The Richards (RCD), the Gompertz (GMP), the monomolecular (MON) and the logistic (LOG) functions were compared for describing the growth curve of 343 female dairy cattle for which 12–18 body-weight measures were available. The animals were divided into four groups, and each function was assigned to one of the groups. Analyses of variance of growth traits estimated by the four functions and of the residual mean squares (RMS) indicated that all differences between functions in estimated mature weight (A) were statistically significant (P < 0.01 to P < 0.0001) except for RCD vs. GMP (P < 0.27). Differences between functions in RMS were significant for RCD vs. LOG (P < 0.0026), MON vs. LOG (P < 0.0044) and GMP vs. LOG (P < 0.0584). RCD differed from all other functions in average lifetime growth rate (P < 0.1 to P < 0.0001) and from MON (P < 0.0004) and GMP (P < 0.0003) in average lifetime maturing rate. Analysis of residuals indicated that both GMP and LOG overestimated birth weight. MON overestimated mature weight, whereas LOG tended to underestimate this parameter. The Richards function was chosen to describe the actual growth curves of individual females of three different genotypes. Predictive equations for the three breed groups were derived. Key words: Dairy cattle, growth curves, nonlinear functions
Effect of postpartum nutrition and cow body condition at parturition on subsequent performance of beef cattle
Authors: Laflamme L. F. , Connor M. L.
Published: March 2010

Seventy-two cows were used in each of 2 yr to study the effect of body condition (BC) and postpartum grain feeding on cow and calf weights and on reproductive traits. Cows reached a BC score of 4 or 6 by parturition and were fed 0 or 4 kg mixed grain d−1 during the postpartum period. All cows were fed grass silage throughout the trial. Grain feeding had no effect on weight gains but increased BC of the lactating cows. Presence of ovarian follicles, uterine involution and pregnancy rate were the only reproductive parameters generally affected by grain feeding. Body condition score had no effect on calf performance, but an increase in BC at parturition yielded an improvement of most of the reproductive traits measured. No interaction was observed between BC and postpartum grain feeding, suggesting that all cows responded similarly to the treatments. Under the conditions of this trial, it was shown that BC at parturition was an important factor affecting cow performance, but the reproductive intervals were directly related to the physiological state of the cow at the beginning of the breeding season. Key words: Cow, body condition, gain, postpartum grain feeding, reproduction
Comparison of alkaloid content and nutritive value for tryptamine- and β-carboline-free cultivars of reed canarygrass (Phalaris arundinacea L.)
Authors: Wittenberg K. M. , Duynisveld G. W. , Tosi H. R.
Published: March 2010

Breeding programs for reed canarygrass (RCG) have resulted in the development of cultivars free of antinutritional compounds such as β-carbolines and tryptamines. The first study was designed to compare nutrient and alkaloid concentrations for four recently released cultivars (Rival, Venture, Palaton, Vantage) and one β-carboline- and tryptamine-containing cultivar (Castor) of RCG. The study was conducted at two locations, over 2 yr, with a two-cut harvest schedule. Cultivar differences were not observed (P > 0.05) for forage crude protein (CP) or neutral detergent fiber (NDF) levels. Rival was observed to have higher (P < 0.05) gramine levels than Venture in 1988 and higher (P < 0.05) hordenine levels than Venture in 1989. A second study was conducted to compare the intake and digestibility for RCG cultivars Rival and Venture using growing lambs. Comparisons were made for initial growth and regrowth forage. Fresh forage was harvested from two paddocks for each cultivar, chopped, bagged with dry ice nuggets 10% wt wt−1 and placed in storage (−10 to −20 °C) until time of feeding. Cultivar differences were not observed (P > 0.05) for intake with the initial growth or the regrowth forage. Apparent digestibility of dry matter was 8.4 and 5.5% units higher (P < 0.05) in Rival than in Venture for initial growth and regrowth, respectively. Similarly, apparent digestibilities of acid detergent fiber and NDF were higher (P < 0.05) for Rival than for Venture at both stages of growth. Forage CP levels differed between cultivars for initial growth; however, levels were comparable for regrowth. In the regrowth, apparent digestibility of CP for Rival was greater (P < 0.05) than for Venture. Key words: Reed canarygrass, low alkaloid, gramine, hordenine, intake and digestibility
Effects of trenbolone acetate on swine carcass characteristics and backfat composition
Authors: Martinez M. , López-Bote C. , Sancho G. , Ventanas J.
Published: March 2010

Twenty-four gilts and 24 barrows were divided into two groups of 12 of each gender. One group was implanted with 300 mg of trenbolone acetate, and the other one was used as a control. Treatment had no effect on fat thickness in gilts but significantly reduced fatness in barrows. The fatty acid composition of the backfat showed a tendency toward greater unsaturation in treated barrows. Key words: Pig, trenbolone acetate, anabolic
The effect of the malignant hyperthermia genotype as determined by a restriction endonuclease assay on carcass characteristics of commercial crossbred pigs
Authors: Pommier S. A. , Houde A. , Rousseau F. , Savoie Y.
Published: March 2010

In 349 crossbred pigs a restriction endonuclease assay used to detect the malignant hyperthermia genotype determined the presence of 84.5% NN pigs, 14.9% Nn pigs and 0.6% nn pigs. A subsample of 149 pigs demonstrated that Nn pigs had a 1% advantage in carcass yield over NN pigs and that meat color was not affected by genotype. Key words: Pigs, carcass, meat, halothane, restriction endonuclease
Evaluation of Rival, Venture and Frontier reed canarygrass as pasture forage
Authors: Duynisveld G. W. , Wittenberg K. M.
Published: March 2010

A grazing study was conducted to determine productivity of the grazing animal on reed canarygrass (RCG) pasture. A total of six 0.5-ha paddocks assigned to three RCG cultivars identified as Rival, Venture and Frontier were used in the 2-yr study. Forage nutrient and alkaloid concentrations and animal performance were monitored under continuous grazing conditions. Above average temperatures and precipitation levels that were 60% of normal were encountered in the first grazing season, resulting in relatively high forage crude protein levels but also high alkaloid concentrations. Animals grazing Frontier paddocks exhibited a high incidence of scouring, preferential grazing and low body-weight gains in the first half of the grazing season. Excessive gramine levels (> 2.0 mg g−1 DM) were observed in all three RCG cultivars during a major portion of this grazing season. A 56-d finishing trial at the end of the grazing season indicated that lambs did not have carryover or residual effects associated with long-term exposure to excessive levels of gramine. Improved growing conditions in the second grazing season resulted in improved pasture carrying capacities, reduced incidence of scouring and no differences among RCG cultivars for animal weight gain. During both grazing seasons, animals grazing Venture paddocks exhibited good weight gains in the initial part of the grazing season, relative to the other cultivars, but weight gains declined more rapidly for animals grazing this cultivar relative to Rival and Frontier as the grazing season progressed. Key words: Reed canarygrass (Phalaris arundinaceae L.), gramine, hordenine, drought, pasture
Calibration curves for the determination of low levels of chromium in feces
Authors: Holt N. W.
Published: March 2010

Chromic sesquioxide is an indigestible marker commonly used in grazing trials. Experiments were conducted to establish a procedure for preparing standard calibration curves for determination of low levels of chromium (Cr) in feces from animals dosed with Cr markers. The calibration curves (prepared using blank feces) were compared with feces-free standards to evaluate the effect of feces on the results. The presence of digested feces reduced the absorption of Cr by 0–5%. The slopes of the calibration curves prepared by digesting the Cr standards with feces were 79–90% of the slopes of standard curves prepared in a feces-free background. When the fecal organic matter was removed by heating with nitric acid followed by digestion with perchloric acid, then the standard Cr could be added with the perchloric acid to best simulate the effect of the acids on apparent loss of chromic oxide in the unknowns. It was essential that feces used for calibration purposes be obtained from animals grazing the same forages as used by the Cr-dosed animals. Key words: Chromic oxide, acid digest, fecal markers
Productivity of Russian wildrye as fall pasture with and without non-protein nitrogen supplementation
Authors: Holt N. W. , Knipfel J. E.
Published: March 2010

Russian wildrye (Psathyrostachys junceus) is recommended for fall pasture but little data are available from grazing trials to substantiate this advice. This study was initiated to evaluate forage yield and quality, and carrying capacity of Russian wildrye as fall pasture. The experiment was conducted at Swift Current, Saskatchewan from 1983 to 988 with Hereford cows and calves as the grazing units. Stockpiled yields of forage, available for grazing, averaged 650 kg ha−1 when determined in September. In vitro organic matter (OM) digestibility averaged 53% and nitrogen content of the forage averaged 1.3%. Yield of forage supported 34 animal-unit grazing days per hectare, when grazed with Hereford cows (540 ± 60 kg) and calves (190 ± 30 kg) for 4–7 wk in September and October. Cows weights were maintained, and calves gained, on average, 0.95 kg d−1. Supplementation with liquid urea-molasses, provided free choice in lick tanks, had no effect on stocking rate or average daily gain of cows or calves. Daily forage intake (OM basis), as measured by chromic oxide dilution, was 2.8% of cow body weight (BW). Daily forage intake by the calves was 1.6% of BW in 1987 and 2.2% of BW in 1988 when OM digestibility of the forage was 54 and 63%, respectively. Forage intake was not affected by supplementation. However, cows allowed access to the supplement grazed 1 h less each day than cows receiving no supplement (7.7 vs. 8.7 h). Russian wildrye provided excellent fall pasture for cows and calves but its production and, consequently carrying capacity, were below levels reported previously. Key words: Psathyrostachys junceus, forage intake, stocking rate
Evaluation of pea screenings and canola meal as a supplementary protein source in barley-based diets fed to growing-finishing pigs
Authors: Castell A. G. , Cliplef R. L.
Published: March 2010

The effects of substituting canola meal (CM) and ground pea screenings (PM) for soybean meal (SBM) in barley (B)-based diets were determined with a factorial design using 60 male castrates (3 pen−1) over the period 25–97-kg average liveweight. The five mash diets (B/SBM, with 15% SBM; B/CM, with 18.7% CM; B/CMp, with 12.4% CM + 14.1% PM; B/PMc, with 6.1% CM + 28.3% PM; and B/PM, with 42.5% PM) contained 2.4% supplement (minerals and vitamins) and were fed ad libitum. Growth rate (821, 845, 850, 880 and 812 g d−1, respectively, P < 0.06) was increased with the CM–PM blends, but gain:feed was unaffected (283, 289, 294, 298 and 293 g kg−1, P > 0.10). Compared with the SBM-fed pigs, using CM reduced the dressing percent, carcass grade, apparent digestibility of energy and nitrogen but increased liver weight (P < 0.01). The B/PM diet may have been deficient in isoleucine for pigs in the initial weeks, but subsequent performance was not impaired. Compared with B/CM-fed pigs, B/PM pigs had higher carcass grades (P < 0.05) and their lean tissue had relatively more marbling (P < 0.01) and a higher degree of saturated fat (P < 0.01). Differences among the five diets, however, did not affect the sensory evaluation of the cooked lean (P > 0.05). Apart from an apparently lower digestibility of energy and nitrogen, results with the mixed-source diets confirmed that CM and PM were complementary sources of supplementary amino acids for growing-finishing pigs. Key words: Pigs, canola meal, peas, growth rate, carcass
Effect of ractopamine on carcass characteristics and joint-cartilage soundness in finishing pigs
Authors: He P. , Aherne F. X. , Thompson J. R. , Schaefer A. L. , Merrill J. K.
Published: March 2010

One hundred and fifty crossbred pigs (Camborough × Canabrid, equal numbers of gilts and barrows) at an average live weight of 64.2 kg were randomly assigned to diets containing 17 or 20% crude protein (with 0.8 or 1.1% lysine, respectively) and 0 or 20 ppm ractopamine. Pigs were slaughtered at an average live weight of 102.2 kg. Supplementation of ractopamine in pig diets significantly increased average daily gain (P < 0.005) and decreased feed to gain ratio (P < 0.001), with no effect on daily feed intake. Ractopamine feeding increased total lean (P < 0.001) and decreased total bone (P < 0.05) and total fat content (P < 0.001) of carcasses. The decreased fat content was largely due to the reduction of subcutaneous fat (P < 0.001). Cartilage visual scores and cartilage uronic acid concentrations of weight-bearing areas of humeral and femoral condyles were not affected by feeding ractopamine. Correlations between visual scores and uronic acid concentrations of joint cartilage and performance parameters and carcass characteristics were not significant. These results demonstrated that feeding ractopamine can increase pig growth rate and carcass leanness without detrimental effect on joint cartilage. Key words: Ractopamine, growth rate, uronic acid, cartilage, osteochondrosis, pigs
Visceral organ weights of swine selected for reduced backfat thickness and increased growth rate
Authors: Cliplef R. L. , McKay R. M.
Published: March 2010

Eight generations of Yorkshire swine and seven generations of Hampshire swine, involving a total of 2300 animals of which 1350 were selected for reduced backfat thickness and increased growth rate, had concurrent increases in visceral organ weights (heart, lungs, spleen, liver and kidney). Implications are that this could amount to 0.4 kg less weight per carcass. Key words: Pigs, organs, selection, Yorkshire, Hampshire
Use of lignosulfonate to decrease the rumen degradability of canola meal protein
Authors: McAllister T. A. , Cheng K.-J. , Beauchemin K. A. , Bailey D. R. C. , Pickard M. D. , Gilbert R. P.
Published: March 2010

Treatment of canola meal (CM) with 5 or 10% lignosulfonate (LSO3) for 1 or 2 h at 100 °C increased borate-insoluble CP and neutral-detergent-insoluble nitrogen and decreased in vitro ammonia concentration compared with untreated or heated CM. Acid-detergent-insoluble nitrogen was increased in 2% xylose and 10% LSO3 CM heated for 2 h. Ruminal degradability of CP was reduced by heating CM (P < 0.01), and this effect was more pronounced (P < 0.001) with LSO3 or xylose. Key words: Cattle, canola meal, lignosulfonate, rumen undegradable protein
Effect of degree of fatness in yearling replacement beef heifers on lifetime performance
Authors: Laflamme L. F.
Published: March 2010

A study was initiated to determine the long-term effect of weight and age at breeding in yearling beef heifers on lifetime performance. Thirty weaned replacement heifers in each of 3 yr were equally fed until breeding on one of three systems: (i) gain of 1 kg d−1 and bred at 350 kg (medium); (ii) gain of 1 kg d−1 and bred at 15 mo of age (high); or (iii) bred at 350 kg and 15 mo of age (low). The high group had an advantage (P < 0.05) in the number of calves produced or weaned, suggesting a greater persistency of production; however, the low group weaned heavier calves. The rearing treatments had no effect (P > 0.05) on the heifer mature weights or on the birth weights of the calves. Most of the differences detected were in the first 5 yr, at which time 50% of the heifers had already been culled. Key words: Beef heifers, rearing, lifetime performance
Effects of dry-matter content on the nutritive value of individually wrapped round-bale timothy silage fed to sheep
Authors: Beaulieu R. , Seoane J. R. , Savoie P. , Tremblay D. , Thériault R. , Tremblay G. F.
Published: March 2010

Thirty-two sheep (30.0 kg avg. BW) were used to study the effects of dry-matter (DM) content at harvest on the nutritive value of timothy grass silages conserved as round bales of high (52.1%, DM50), medium (39.9%, DM40) and low (23.1%, DM25) DM. Chopped grass of 24.4% DM conserved in a horizontal silo (HS) was used as a control. Gross energy, crude protein (CP) and acid detergent fibre (ADF) contents were similar for all silages (P > 0.05). Neutral detergent fiber (NDF) contents decreased as DM of the silages decreased (P < 0.05). Acid detergent lignin and ash contents were highest in HS and lowest in DM40 silages (P < 0.05). Silage pH and water-soluble carbohydrates decreased with decreasing DM of the silages (P < 0.05), while ammonia-N and lactate levels increased (P < 0.05). Acetate concentrations in round bales were lower than in HS silage (P < 0.05). Significant butyrate concentrations were detected only in DM25 silage. Round-bale silages were chopped before feeding and fed ad libitum. DM intake was 14.5% higher for DM50 and DM40 silages than for DM25 and HS silages (P < 0.001). Average daily gain and feed efficiency were higher for high-DM silages than for DM25 and HS silages (P < 0.01). Apparent digestibilities of NDF, cellulose and crude fiber of the silages were similar, but DM, organic matter, energy and hemicellulose digestibilities were higher for HS than for DM25 silage. Apparent digestibilities of ADF and CP were higher for high-DM silages than for DM25 and HS silages (P < 0.04). The results indicate that to obtain good-quality silage, the DM content of round bales should be 40–50%. The better performance obtained with high-DM silages was indicative of a more efficient utilization of metabolizable energy for gain. Key words: Round-bale silage, timothy, forage
Maternal factors and the prediction of dystocia in beef heifers
Authors: King B. D. , Cohen R. D. H. , McCormac S. , Guenther C. L.
Published: March 2010

Stepwise discriminant analysis was used to determine maternal factors associated with dystocia in 564 2-yr-old heifers bred to bulls with below breed average birth weights. Calf birth weight (n = 556) was consistently the most significant (P < 0.001) factor correlated (R2 = 0.31) with dystocia. Other significant (P < 0.001) factors were weight at breeding (n = 376) and calving (n = 559; R2 = 0.11 for both traits). Other factors considered were age at breeding (n = 446), pelvic area at breeding (n = 112) and pregnancy evaluation (n = 297), heifer birth weight (n = 564), gestation length (n = 467) and age at calving (n = 559) but none were significant (P > 0.05). Heifers requiring caesarian section were heaviest (P < 0.05) at breeding and their calves were heaviest (P < 0.05) at birth. Unassisted heifers were heavier at calving (P < 0.05) than assisted heifers. It was concluded that none of the factors examined in this study was a reliable predictor of dystocia in beef heifers but that heifers should be bred at 75–80% of their expected calving weight to reduce the risk of dystocia. Key words: Dystocia, heifer, discriminant analysis
Proteolysis and rumen degradability of alfalfa silages preserved with a microbial inoculant, spent sulfite liquor, formic acid or formaldehyde
Authors: Marshall S. A. , Campbell C. P. , Buchanan-Smith J. G.
Published: March 2010

The efficacy of biological additives and direct acidifiers on the preservation and extent of proteolysis in unwilted alfalfa silage was investigated using a 2 × 3 × 5 factorial design. Alfalfa, harvested as unwilted second-cut (21% dry matter (DM)) and third-cut (17% DM) material was ensiled untreated or treated with formic acid (0.4%) or a microbial inoculant (Ecosyl: ICI Biologicals, Mississauga, ON), with or without formaldehyde (0.2%) or three levels of spent sulfite liquor (SSL) (0.25, 0.50 and 0.75%) in laboratory silos for 90 d. Addition of direct acidifiers (formic acid with or without formaldehyde or SSL) reduced pH and enhanced levels of water-soluble carbohydrates (WSC) and lactic acid. Proteolysis of unwilted second- and third-cut silage as measured by soluble nitrogen (N), nonprotein N (NPN) and ammonia N (NH3-N) concentration was reduced (P < 0.05) relative to controls (untreated, formaldehyde and SSL). Biological additives (Ecosyl with or without formaldehyde or SSL did not differ (P > 0.05) from controls in second-cut silage. However, addition of biological additives reduced (P < 0.05) proteolysis of third-cut forage compared with controls. No linear response in extent of acidification or proteolysis by increasing levels of SSL was found. In a subsequent experiment, three rumen-fistulated Hereford steers were used in a randomized incomplete block design to investigate whether the chemical profile of N constituents of unwilted alfalfa silages could be used to predict protein degradability of silage incubated in nylon bags. Individual silages which demonstrated a marked difference in NPN content from untreated controls were incubated. Addition of formic acid and formaldehyde increased (P < 0.05) the potentially degradable insoluble N fraction while decreasing (P < 0.05) the rumen soluble N fraction, which was found to be positively correlated (r = 0.72, P < 0.0001) with NPN content of silage. There was no relationship between NPN and extent of ruminal protein disappearance (r = 0.08, P < 0.65); however, total N, total soluble N and NPN were found to be positively correlated to protein degradability (r = 0.68, P < 0.0001; r = 0.61, P < 0.0001; and r = 0.67, P < 0.0001, respectively). Key words: Alfalfa, silage, inoculant, degradability, steers
Effects of dietary barley level on the performance of Leghorn hens
Authors: Hamilton R. M. G. , Proudfoot F. G.
Published: March 2010

Three experiments were carried out to examine the effects of dietary barley level on the performance of Leghorn hens. A 4 × 2 factorial arrangement of treatments was used in exps. 1 and 2 where there were four dietary barley levels (0, 15, 30 or 60%) and two commercial genotypes of hens. Experiment 3 contained a 3 × 2 × 2 arrangement of treatments involving three dietary barley levels (15, 30 or 60%), two cultivars of barley (2- or 6-row) and two levels of β-glucanase supplementation (0 and 0.1% of the diet). Egg production, feed intake, mortality, egg grades, body weight, and eggshell and interior quality data were collected from 140 to 490 d of age. The data from exps. 1 and 2 were combined for statistical analysis. There was a linear relationship (P < 0.001) between dietary barley level and feed conversion in exps. 1 and 2. Differences (P ≤ 0.05) were observed between the two genotypes for 140- and 490-d body weights, age at 50% egg production, hen housed egg numbers, feed conversion and monetary returns. Dietary barley level, in exp. 3, had a quadratic effect (P ≤ 0.05) on egg production (both HD % and HH no.) and monetary returns and a linear effect (P < 0.01) on feed conversion. Source of barley and dietary β-glucanase supplementation had little effect on performance. Diets for Leghorn hens may contain up to 60% barley, but optimum production performance occurred at a lower level. Key words: Barley, hens, β-glucanase, barley cultivar
Comparison of viability scoring and blood gas analysis as measures of piglet viability
Authors: Zaleski H. M. , Hacker R. R.
Published: March 2010

Viability score based on heart rate, colour, muscle tone, respiration, and attempts to stand was correlated with pH (r = 0.82, P = 0.0001), pCO2 (r = − 0.85, P = 0.0001), and pO2 (r = 0.27, P = 0.0001) in 1217 neonatal piglets, indicating that viability score is an excellent measure of the extent of asphyxia suffered by piglets during parturition. Key words: Viability, blood gas, neonatal pig
Characteristics of dioxane-soluble lignins from corn and sorghum silages and feces of sheep fed on them
Authors: Kondo Tsuneo , Ohshita Tomoko , Kyuma Tadashi
Published: March 2010

Dioxane-soluble lignin fractions were isolated from corn and sorghum silages, and the feces of sheep fed on them and their properties were examined. The lignin fractions were composed chiefly of soluble lignin fragments with different molecular weights and contained phenolic acid esters as non-core lignin components. A comparison of the analytical data showed that the soluble lignins from the silages had different properties from those of corresponding feces, suggesting structural changes of lignins in the digestive tract of sheep. Key words: Dioxane-soluble lignin, silage, corn, sorghum, sheep digestion
Effect of water sweetener on the performance of newly weaned pigs offered medicated and unmedicated feed
Authors: Maenz D. D. , Patience J. F. , Wolynetz M. S.
Published: March 2010

The effects of drinking water supplemented with a commercial sweetener on the performance of newly weaned pigs given medicated or unmedicated pig starter feed was evaluated in four replicate 10-d trials. A significant (P < 0.01) positive correlation (r = 0.51) was found between cumulative feed intake and cumulative water intake. However, sweetening the drinking water was ineffective in promoting water intake and improving the performance of newly weaned pigs. Key words: Water, sweetener, antibiotics, swine
Effect of oat bran, cotton seed hulls and guar gum on chicken egg and blood lipids during the early laying period
Authors: Lirette A. , Crober D. C. , Lawson P. D. , Firth N. L. , Robinson A. R.
Published: March 2010

Fifteen Leghorn pullets were assigned to each of four experimental diets: basal layer ration or basal ration containing 30% oat bran, 3% cotton seed hulls or 0.5% guar gum from 19 to 25 wk of age. Inclusion of oat bran and cotton seed hulls lowered (P < 0.05) egg yolk cholesterol concentration 6 to 7%, but had no significant (P > 0.05) effects on early production parameters. Key words: Chicken, egg, cholesterol, cotton seed hulls, oat bran, guar gum
Carcass composition of cull sows
Authors: Aziz N. N. , Rae W. A. , Ball R. O. , Allan J. W.
Published: March 2010

Two hundred and four sows were slaughtered in seven weight classes (WCs) from < 99.9-kg to > 225-kg carcass weight in 25-kg increments and 11 fat classes (FCs) from < 9.9-mm to > 55-mm backfat depth in 5-mm increments. Backfat thickness (probe fat) and loin muscle depth (probe lean) were measured on the left side of the carcass between 3rd and 4th last rib 7 cm from midline by electronic probe. The left side was cut into four primals: shoulder, ham, loin and belly. Shoulder, ham and loin were then separated into trimmed commercial cuts to determine commercial yield and then defatted and deboned to determine retail yield, lean yield, fat yield and bone yield. Dressing percentage was lowest for those sows in fat class 1 (77.4%) and highest for those in fat class 11 (83.7%). Percentage of shoulder and ham in the carcass side decreased, while the percentage of the loin and belly increased as WC and FC increased. FC produced significant effect on the percentage of the shoulder, loin and belly, whereas WC had significant influence only on the proportion of the shoulder and belly. There was a significant WC × FC interaction (P < 0.002) upon the percentage of the belly yield. The percentages of commercial yield, retail yield, lean yield and bone yield were reduced, and that of fat yield increased as WC and FC increased, but WC only produced significant effects on the percentage of lean and bone yield. Carcass composition of cull sows was better correlated to backfat thickness than carcass weight, since the increase in carcass weight as live weight increased was primarily fat. Key words: Carcass composition, sows, lean yield
Prediction of lean yield in cull sows
Authors: Aziz N. N. , Rae W. A. , Ball R. O.
Published: March 2010

Data from 204 sows were used to predict percentage carcass lean yield and lean weight. Backfat thickness (probe fat) and muscle depth (probe lean) were measured with an electronic probe. Fat thickness was also measured by ruler at the midline at maximum fat depth over the lumbar vertebrae (maximum fat), fat depth at the last rib (last-rib fat), and fat depth between the 3rd- and 4th-last ribs (fat depth 3–4). Fat depth over maximum loin-muscle depth (loin fat 1), maximum fat depth over loin muscle (loin fat 2), maximum loin depth (loin lean 1) and maximum loin width (loin lean 2) were measured on loin cross section. On the warm carcass, the prediction accuracy of percentage lean yield was highest for probe fat (R2 = 0.77), whereas probe lean had the lowest coefficient of determination (R2 = 0.01). Among the ruler measurements, maximum fat was associated with the most accurate prediction of percentage lean yield (R2 = 0.71). Among cross-section measurements, loin fat 2 was the most accurate predictor of percentage lean yield (R2 = 0.78). For predicting lean weight in the carcass, carcass weight gave the highest coefficient of determination (R2 = 0.82) of any single measurement, but addition of probe fat to the equation improved R2 by 11% and reduced the RSD from 3.16 to 2.00. A single measurement by probe (probe fat) or ruler (maximum fat) was concluded to be sufficient to accurately predict percentage lean yield in sow carcasses. Key words: Lean yield, sows, prediction, carcass composition, grading
Effect of β-glucanase/pentosanase enzyme supplementation on the performance of chickens and laying hens fed wheat, barley, naked oats and rye diets
Authors: Brenes A. , Guenter W. , Marquardt R. R. , Rotter B. A.
Published: March 2010

Three experiments were conducted to evaluate the effects of β-glucanase/pentosanase enzyme complex (Trichoderma viride, Roxazyme® G) on the performance of Leghorn chicks and laying hens fed wheat, barley, oats or rye diets. In the first experiment, enzyme addition (0.2 and 0.4 g kg−1) improved weight gain and feed efficiency in Leghorn chicks fed hulless barley (45 and 18%, respectively) and naked oat-based diets (35 and 15%, respectively). No response to dietary enzymes was evident when chicks were given the wheat diet. In the second experiment, the addition of Roxazyme® G to diets containing hulless barley (0.1 g kg−1) and rye (4.0 g kg−1) improved feed consumption (8 and 16%, respectively), weight gain (21 and 35%, respectively) and feed-to-gain ratios (11 and 14%, respectively). Relative gizzard weights of birds fed the rye diet were reduced by 18% when enzyme was added to this diet. In the third experiment, replacing all the wheat with hulless barley, naked oats or rye in diets for young pullets had no effect on overall performance during a 12-wk laying trial. Vent feather soilage increased with the incorporation of naked oats and rye. Enzyme supplementation had a beneficial effect on weight gain and feed intake but not on egg production, initial egg weight, average egg weight, egg specific gravity, Haugh unit score, and mortality. Key words: Grain, chickens, laying hens, dietary enzyme
Influence of feeding and diet on diurnal patterns of plasma growth hormone and insulin in calves
Authors: Mears G. J.
Published: March 2010

Plasma GH concentrations were lower after feeding than before (newborn calves, P < 0.05; steers, P < 0.01). Calves fed concentrate had higher plasma insulin concentrations than those fed hay (P < 0.01). Meal feeding milk or concentrate, but not hay, elevated plasma insulin (P < 0.05). Diet type and feeding time relative to sampling time must be considered when measuring GH and insulin. Key words: Diurnal patterns, growth hormone, GH, insulin, calves
Articular cartilage lesions in female breeding swine
Authors: Nakano T. , Aherne F. X.
Published: March 2010

Nineteen sows culled because of impaired reproductive performance were examined postmortem for abnormalities of the femoral condylar cartilage. All animals had lesions of varying severity, including irregular articular surface, surface tears, and erosion of the cartilage. The etiology of these cartilage lesions is discussed in relation to confinement. Key words: Articular cartilage lesion, osteoarthrosis, confinement, sows
An economic comparison of beef cattle genotypes for feedlot traits at their optimal slaughter end point
Authors: Amer P. R. , Kemp R. A. , Smith C. , Fox G. C.
Published: March 2010

A bioeconomic model is used to compare beef breeds and crosses for their economic performance in the feedlot. Breeding objectives for each breed and cross are also calculated. Comparisons are made on the basis of the expected purchase-price premium paid for a breed, cross or animal when slaughtered at its profit-maximizing end point. These comparisons are relevant to commercial beef producers who ultimately have to choose between genotypes. Purebred Charolais are expected to capture a premium over purebred Angus of approximately $71 and $45 animar−1 for steers and heifers, respectively. Simmental, Limousin and Hereford purebreds are intermediate, with differences between them relatively small in comparison with the expected effects of errors in model parameters. Crosses between exotic type (Charolais, Simmental and Limousin) and British type (Hereford and Angus) breeds have larger increases in purchase-price premiums over the mid-parent mean than crosses within the types. Averaged economic weights for 1% changes in the mean of +12 g d−1, −80 g d−1 and 0.6% in daily gain, daily feed intake and dressing percentage are $3.7 animal−1, $1.8 animal−1 and $8.4 animal−1, respectively. These are relatively consistent across breeds, crosses and sexes. In contrast, economic weights for fat depth at a constant weight are shown to be nonlinear and therefore are highly dependent on the breed, cross and sex and the slaughter end point at which they are calculated. At the economic optimum slaughter point in the base, exotic breeds and crosses between them tended to have negative economic weights for a reduction in fat depth, whereas British breeds were the opposite. Economic weights tend to be small and positive for a reduction in fat depth in crosses between the two breed types. Key words: Beef cattle, feedlot, end point, optimization, bioeconomic model