bluuebunny/crossref_metadata_2025 huggingface dataset:
In situ rumen digestion and escape of dry matter, nitrogen and amino acids in canola meal
Authors: Boila R. J. , Ingalls J. R.
Published: March 2010

Three rumen-cannulated steers were used in three separate trials wherein canola meal (CM) was incubated in situ for 0.1, 4, 8, 12, 16 and 36 h in Dacron bags. Disappearance parameters were estimated for dry matter (DM), nitrogen (N) and individual amino acids (AAs). Effective degradabilities (EDs) were estimated at rumen particulate outflow rates of 0.08, 0.05 and 0.02 h−1. An ED for DM that was lower than that of most AAs indicated there was a limit to its degradability. In contrast, the ED of N was higher than that of 11 of 17 AAs; the disappearance parameters for N were a poor indicator of those estimated for individual AAs. The concentrations of AAs in escape CM estimated at the specified rumen outflow times, compared with non-incubated CM, were higher for all AAs except cystine, proline and glutamate, whose concentrations were lower, and histidine and arginine, whose concentrations did not differ. Compared with non-incubated CM, in escape CM there was a 33% reduction in concentration of glutamate, a 28% enrichment of tyrosine, a lower enrichment, ranging from + 14 to + 23%, for valine, isoleucine, threonine, phenylalanine, serine, aspartate and alanine, and little change in concentration for other AAs. Although the concentrations of AAs in rumen escape CM differed from that in non-incubated CM, those concentrations in escape CM were relatively uniform among outflow rates of 0.08, 0.05 and 0.02 h−1. Key words: Canola meal, in situ digestion, rumen degradability, rumen escape, protein, amino acids
Age-related carcass composition changes in male broiler chickens
Authors: Perreault N. , Leeson S.
Published: March 2010

To quantify growth and development of the broiler chicken to 70 d, a flock of male birds was sampled at regular intervals, and observations were made on growth and development of various carcass components. Birds were fed conventional diets and maintained on litter-floor pens in a room with environmental control. At 21, 28, 35, 39, 43, 47, 50, 55, 60 and 70 d of age, 12 birds were selected at random for estimation of live weight, eviscerated weight, cut-up portion composition and deboned meat yield. Observations involved weights of the various carcass components and proximate analysis. Birds showed linear growth to 70 d (P < 0.01), while development shown by the eviscerated carcass was positively quadratic (P < 0.01). Proportional fat content of the eviscerated carcass increased over time (P < 0.01), while protein content decreased (P < 0.01). The leg-thigh portion yielded the greatest quantity of meat, while the bone portion increased from 130 g to 843 g over the 21- to 70-d period. Total carcass skin increased in weight from 50 g to 365 g over the same period. Both deboned breast meat and leg meat increased quadratically over time (P < 0.01). Comparison of results with that developed 10–15 yr ago indicates chronological changes in carcass development. An apparent sporadic increase in yield of breast and thigh meat, which has also been shown by other workers, warrants further investigation. Key words: Broiler, carcass composition, meat yield
Effect of zeranol on fat deposition and carcass traits in beef heifers
Authors: King B. D. , Bergen R. D. , McKinnon J. J. , Cohen R. D. H. , Kirkwood R. N.
Published: March 2010

Non-pregnant beef heifers implanted with zeranol at birth and at 100 and 200 d of age were fed a finishing ration for 78 d to slaughter at 21–22 mo of age. Rate of fat deposition, grade fat and marbling score were less (P < 0.05) and carcass weight, rib-eye area and lean-meat yield were greater (P < 0.05) for implanted heifers than for non-implanted heifers. Key words: Zeranol, ultrasound, fat deposition, carcass, beef heifer
Feeding Jerusalem artichoke flour rich in fructooligosaccharides to weanling pigs
Authors: Farnworth E. R. , Modler H. W. , Jones J. D. , Cave N. , Yamazaki H. , Rao A. V.
Published: March 2010

Weaned pigs were fed a control diet or one containing 1.5% Jerusalem artichoke tuber flour (JAF) containing fructooligosaccharides or 1.5% Neosugars (NS) for 4 wk. Experimental parameters, including feed intake, body-weight gain, feed efficiency, digesta volatile fatty acid levels and microbiological profile were not significantly affected by diet. Key words: Jerusalem artichoke, fructooligosaccharide, bifidobacteria
Effects of acute and chronic administrations of naloxone on plasma luteinizing hormone and prolactin in broody turkey hens (Meleagris gallopavo)
Authors: Guémené D. , Etches R. J.
Published: March 2010

The effects of acute and chronic administration of naloxone, an opioid antagonist, on luteinizing hormone (LH) and prolactin concentrations were investigated in broody turkey hens. Naloxone failed to induce any changes in the plasma prolactin concentrations in the hens. On the other hand, an intravenous injection of naloxone (6 mg kg−1 BW) decreased plasma concentrations of LH. Conversely, LH concentrations were significantly increased after infusing 10 μg h−1 of naloxone for 7 d. No changes in behavioral pattern, feed intake and water consumption were observed during and following infusion of naloxone in comparison with controls. These results indicate that a role of the endogenous opioids in the modulation of LH release cannot be excluded and further investigations are needed to clarify this relationship. On the other hand, there is little support for any role of opioids in the maintenance of the high level of prolactin concentrations associated with the expression of broodiness. Key words: Naloxone, luteinizing hormone, prolactin, broody turkey hens
Corn or alfalfa as the forage source in predominantly silage diets for late-lactation dairy cows
Authors: Charmley E. , Robinson P. H. , McQueen R. E.
Published: March 2010

Twelve multiparous and three primiparous cows were used in a 10-wk lactation study with two repeated measures to evaluate diets containing 90% timothy–alfalfa silage (TA), 84% corn silage (CS) or an equal mixture of each (TA–CS). Each diet was supplemented with minerals to meet requirements; barley was used as a carrier. Diets CS and TA–CS were also supplemented with urea, casein and soybean meal, making them similar to TA for undegraded intake protein (UIP) and degraded intake protein (DIP) levels. Two of the cows on each treatment were fitted with a ruminal cannula. There were no treatment effects on intake (27 g DM kg−1 BW), body-weight change or body-condition score. Milk yield averaged 15.3 kg d−1 and was not treatment influenced (P > 0.05); however, yield of fat and protein and percentage of lactose in milk showed a linear response to increased corn silage in the diet (P < 0.05). Rumen pH was least and rumen ammonia concentration greatest in the mixed silage diet (P < 0.05). Rumen pool sizes of organic matter and neutral detergent fiber were not treatment influenced (P > 0.05). All treatments supported modest levels of production for cows in late lactation, with increasing dietary energy density from corn silage increasing energy output in milk. Key words: Dairy cow, silage diets, forage species, milk production
Studies on canola seed in turkey grower diet: Effects on ω-3 fatty acid composition of breast meat, breast skin and selected organs
Authors: Ajuyah A. O. , Hardin R. T. , Sim J. S.
Published: March 2010

The use of full-fat canola seed as a source of ω-3 fatty acids in rations for turkeys was assessed in 12-wk-old Nicholas heavy broiler turkeys of both sexes. Results indicate that dietary C18:3ω3 from full-fat canola seed is readily absorbed and converted to its longer chain metabolites (C20:5ω3, C22:5ω3, and C22:6ω3) prior to tissue deposition. Key words: Canola, turkeys, ω-3 fatty acids
Effects of processing methods for soybean meal used in milk replacers on intestinal xylose uptake and serum antibody to soybean antigen when fed to calves of various ages
Authors: Mir P. S. , Burton J. H. , Burnside E. B. , Wilkie B. N.
Published: March 2010

Milk replacer containing either heated soybean meal (commercial soybean meal), extruded soybean meal, ethanol-extracted soybean meal, fermented soybean meal or skim milk powder replacer (SMPR) was fed for 20 d to preruminant calves from either 6, 18 or 30 d of age (age groups 1, 2 and 3, respectively). Effects of these diets on intestinal absorption efficiency (using the xylose absorption test), serum antibody titres to the soybean allergens, and concentrations of immunoglobulin isotypes (IgG1, IgG2, IgM and IgA) were determined. Peak plasma xylose concentrations were highest in calves receiving SMPR; these values were 45.8, 56.3 and 54.0 mg dL−1 for calves in the three age groups, respectively. Calves in age group 1, fed the extruded soybean meal replacer, had the lowest peak plasma xylose concentration (32.8 mg dL−1). Increases in peak plasma xylose concentration were not observed in calves in age groups 2 and 3 relative to those in age group 1 for the heated soybean meal replacer unlike those noted in calves receiving the other milk replacers. Antibodies to the soybean antigens glycinin and β-conglycinin were detected in serum of all the calves, but those receiving the heated or extruded soybean meal appeared to have higher serum titres than those receiving the ethanol extracted or the fermented soybean meal. Key words: Processed soybean meal, calves, milk replacers, xylose absorption, antibody titres, glycinin, β-conglycinin
The concentration of selenium in the grain from wheat, barley and oats grown at selected locations throughout Manitoba
Authors: Boila R. J. , Stothers S. C. , Campbell L. D.
Published: March 2010

The concentration of Se was measured in grain from wheat, barley and oats grown at 12 different locations throughout Manitoba. Concentrations in individual samples ranged from deficient (< 0.1 mg kg−1 DM) to higher than the maximum tolerable (> 2.0 mg kg−1 DM) by livestock. Within a location, the concentration of Se in a grain differed (P < 0.05) among years. Key words: Selenium, grain, wheat, barley, oats, Manitoba
The effect of ante mortem electrolyte therapy on animal physiology and meat quality in pigs segregating at the halothane gene
Authors: Schaefer A. L. , Murray A. C. , Tong A. K. W. , Jones S. D. M. , Sather A. P.
Published: March 2010

The present study was initiated to investigate the effect of oral potassium (600 mg, slow release, 24 h preslaughter), intramuscular (IM) magnesium (500 mg MgSO4, 2 h preslaughter) or slow release magnesium (Magnesium-aspartate-hydrochloride (Mg Asp) 20 or 40 (g d−1 for 5 d) on animal physiology and pork quality. Experiments were undertaken on 318 barrows and gilts (100 kg ± 5 kg) represented by three genotypes segregating at the halothane locus (nn, Nn and NN genotypes). Experiment 1 indicated that the oral potassium effectively (P ≤ 0.05) reduced pCO2 values in the nn genotype. Intramuscular injectable magnesium treatments were also found to raise plasma magnesium (P < 0.05) but did not alter muscle, liver or heart tissue levels. Both oral potassium and i.m. magnesium exacerbated subjective pork structure and texture scores but were found to increase muscle brightness and hue (higher b* value). In exp. 2, oral magnesium-aspartate (Mg Asp) was found to raise plasma, but not tissue, levels of magnesium. When fed to a group of halothane carrier pigs (Nn genotype), Mg Asp reduced muscle temperature 45 min post-stunning, increased muscle redness (CIE a* value) and reduced muscle drip loss (P < 0.06). It was concluded that oral potassium and i.m. magnesium as administered in the present study had no beneficial effects on pork quality but that the beneficial effects of Mg Asp on meat colour and drip loss may warrant further investigation. Key words: Magnesium, potassium, preslaughter, pork quality, PSE pork
Effect of the dominant follicle on regression of its subordinates in heifers
Authors: Adams G. P. , Kot K. , Smith C. A. , Ginther O. J.
Published: March 2010

The relationship between a dominant follicle of a follicular wave and the suppression of subordinate follicles was studied during the first postovulatory wave (Wave 1) in Holstein heifers. The dominant follicle (largest follicle) was cauterized or a sham-operation was done on day 3 (day 0 = ovulation) using seven heifers per group. In the cautery group, compared to the controls, the largest subordinate follicle attained a larger diameter (11 7 vs 8 0 mm; P < 0.01), reached maximum diameter at a later day (day 9.2 vs. day 3.1; P < 0 01) and began to regress at a later day (day 14.3 vs. day 5.7; P < 0.01). In addition, the emergence of Wave 2 was hastened (day 6.4 vs. day 9.3; P < 0.05) and more heifers had more than two waves per interovulatory interval (5 of 6 vs. 2 of 7; P < 0.05). In heifers with the dominant follicle eliminated, the largest subordinate grew to the diameter of a dominant follicle during Wave 1 (n = 3) or became the dominant follicle of a newly emerged wave (n = 2). A subordinate sometimes persisted as a small follicle (e.g., 5 mm) for several days before resurging. However, it was not convincingly demonstrated that a subordinate follicle could resurge after it had begun to regress (decrease in diameter). Results supported the hypothesis that suppression of subordinate follicles is a prolonged process, so that resurgence of a subordinate can occur if the dominant follicle is removed. Key words: Ovaries, follicular waves, selection, cattle, cauterization
The effects of dietary energy and crude protein concentration on growth and serum insulin-like growth factor-I levels of cattle that differ in mature body size
Authors: McKinnon J. J. , Cohen R. D. H. , Laarveld B. , Christensen D. A. , Jones S. D. M.
Published: March 2010

An experiment was conducted to examine the influence of dietary energy level (11.17 and 11.88 MJ ME kg−1 DM) and crude protein (CP) level (11, 13 and 15% DM basis) on growth and carcass composition and plasma insulin-like growth factor-I (IGF-I) levels of medium frame (MF) and large frame (LF) cattle. Dietary energy level or CP level did not influence the growth of MF steers. Averaged across energy levels, the growth of LF steers increased linearly (P < 0.01; R2 = 0.60) with dietary CP level. No influence of protein level was observed on carcass tissue gain. Apparent CP and DM digestibilities increased (P < 0.05) with increasing CP level on low- but not high-energy rations. Serum IGF-I levels were higher (P < 0.05) in MF steers and in animals fed high-energy rations. Little or no association was observed between serum IGF-I levels and indices of growth or carcass composition. It was concluded that the growth of LF steers was improved on diets formulated to CP levels in excess of those currently recommended. However, the biological mechanism responsible for the improved growth is not clear. Key words: Steers, frame size, protein, energy, IGF-I
Crude protein requirements of large frame cattle fed two levels of energy as weaned calves or as backgrounded yearlings
Authors: McKinnon J. J. , Cohen R. D. H. , Christensen D. A. , Jones S. D. M.
Published: March 2010

Two trials were conducted to determine the crude protein (CP) requirements of large-frame (LF) cattle managed under two regimes and fed one of two energy levels. Trial 1 involved 216 recently weaned LF calves, while trial 2 involved 192 LF backgrounded yearling steers. In each trial, the cattle were fed diets formulated to one of two energy levels (11.17 and 11.88 MJ ME kg−1 DM) and one of six CP levels (11, 13, 15, 16, 17 and 19% DM basis). High-energy feeding increased (P < 0.05), average daily gain (ADG), average daily carcass gain (ADCG) and average daily fat gain (ADFG) of weaned calves but did not influence the performance of the backgrounded yearlings. Weaned calves fed 16, 17 or 19% CP had higher (P < 0.05) ADG than those fed 11%, while those fed 16% CP exhibited increased (P < 0.05) ADFG. ADG and ADCG of weaned calves and backgrounded yearlings and ADFG of weaned calves fed low-energy diets increased (P < 0.05) linearly with increasing dietary CP concentration. Daily carcass lean gain of weaned calves fed low-energy diets decreased in a quadratic manner (P < 0.05) as dietary CP level increased. No influence of dietary CP concentration was observed on carcass tissue gain of the backgrounded yearlings. It was concluded that energy balance of animals fed low-energy diets improved with CP supplementation and that current NAS-NRC (1984) CP requirements accurately predict performance of LF cattle. Key words: Steers, growth, carcass composition, energy, crude protein
Evaluation of naked oat (Avena nuda) in the broiler chicken diet
Authors: Cave N. A. , Burrows V. D.
Published: March 2010

Broiler chickens were fed starter diets containing 0, 250 or 500 g kg−1 naked oat and, from 29 to 40 d of age, grower diets with 0, 250, 500 or 750 g kg−1 naked oat. All diets included an enteric antibiotic and water-miscible forms of vitamins A, D, E and K. Broiler performance, as evaluated by weight gain and feed:gain ratio, was as good as or better than the corn-soy control diet with up to 500 g kg−1 naked oat in the starter diets. A starter-by-grower diet interaction showed that weight gain was independent of oat level in the grower diet of birds previously fed naked oat, but gain was impaired by higher levels of oat following an oat-free starter diet. Carcass quality improved with increasing oat level in the starter diet by a decrease in abdominal fat and a decrease in oxidation of thigh meat lipids. Key words: Oat (naked), growth, carcass fat, broiler chicken
High protein and low trypsin inhibitor varieties of full-fat soybeans in broiler chicken starter diets
Authors: Chohan A. K. , McNiven M. A. , Hamilton R. M. G. , MacLeod J. A.
Published: March 2010

Two broiler growth trials of randomized block design were conducted to evaluate the nutritional quality of two new varieties of full-fat soybeans (SB) in starter diets. Use of the high protein (HP) SB (44% CP) has the potential to replace conventional soybeans in poultry rations and reduce the amount of SB needed. Use of the low-trypsin inhibitor (LTI) SB may eliminate the cost of heat treatment before feeding to poultry. The protein sources were raw SB (39% CP, 70 Trypsin Inhibitor Units (TIU) g−1 DM), autoclaved SB, autoclaved HP SB, LTI (42 TIU g−1 DM) and commercially roasted SB. Diets were formulated to be isonitrogenous and isoenergetic. Supplementation of diets with 0.3% DL-methionine was also studied, as the antiproteolytic activity of the TI makes sulphur amino acids less available for growth. Mean body weight gains, feed efficiency, dry matter and crude protein digestibilities and total carcass protein and energy content of the chickens fed HP, autoclaved or roasted SB were superior (P < 0.05) to those fed the raw SB diet. Performance of the chickens fed the HP SB diet was similar to those on the roasted SB diet. Growth and feed conversion of chicks fed the LTI diet were similar to those fed the raw SB diet. However, mean pancreas weights of the chicks fed LTI were lower (P < 0.001) than those fed raw SB which could be due to the lower trypsin inhibitor activity of the LTI beans. Chickens given the methionine supplemented LTI diet made greater weight gains (P < 0.05) than those on the nonsupplemented diet. Heat treatment is required for the LTI beans. Full-fat HP soybeans may replace conventional soybean meal in broiler chicken starter diets if the formulation is adjusted for the differences in their protein and fat contents. Key words: Soybeans, trypsin inhibitor, broiler, chicken growth
Preweaning losses of piglets as a result of index selection for reduced backfat thickness and increased growth rate
Authors: McKay R. M.
Published: March 2010

Index selection for reduced backfat thickness and increased postweaning growth rate resulted in increased preweaning death losses due either directly or indirectly to the sow in the Yorkshire and Hampshire breeds. This resulted in a reduced percentage of piglets weaned in the Yorkshire breed. Key words: Swine, selection index, preweaning period, mortality, survival
Effect of supplemental vitamin E and selenium in the diet on vitamin E and selenium levels and control of oxidized flavor in milk from Holstein cows
Authors: Charmley E. , Nicholson J. W. G. , Zee J. A.
Published: March 2010

Twenty-four mid-lactation Holstein cows of mixed parity were used in a 2 × 2 factorial design to examine the effects of vitamin E and Se supplementation on performance, levels of anti-oxidants in milk and resistance of milk to oxidation. Only a proportion of cows (25%) produced milk susceptible to oxidation; however, there was a trend (P = 0.11) toward reduced oxidized flavor when vitamin E was given. Milk production was increased when either vitamin E or Se were given alone (P = 0.056). Supplementation with 8000 IU dl-α-tocopheryl acetate d−1 approximately doubled α-tocopherol concentration in blood and milk (P < 0.001). Se supplementation with Se-enriched yeast at 5 mg d−1 increased Se levels in milk from 13.2 to 34.7 μg L−1 (P < 0.001). Key words: Vitamin E, tocopherol, selenium, milk, oxidized flavor, cow
Related responses in the live performance and carcass measurements of progeny from sows selected for thinner backfat
Authors: Castell A. G. , Cliplef R. L.
Published: March 2010

Landrace-sired progeny (B-boars, G-gilts and CM-castrates) were obtained from sows in two Hampshire lines (Control, Select) derived by applying a selection index which had three times the emphasis on backfat reduction than on post-weaning growth to 90 kg. Experiment 1 used 72 pigs from the Generation 1 sows and a split-plot design with line as the main plot and sex-type as the sub-plot. A 16% CP diet was fed, ad libitum, in the 24 pens over the period from 26 to 100 kg liveweight. No significant (P < 0.05) differences in live performance or carcass measurements were found between pigs from the two lines. However, characteristic differences among the sex types were observed, e.g., the slower growth by G, higher intake by CM and superior gain:feed by B. Experiment 2, following the same format with Generation 5 progeny (N = 90 and 30 pens), revealed a difference (P < 0.01) in daily intake (ADI) relative to liveweight (LWT) between Control (ADI = 123 × LWT0.729; R2 = 0.89, P < 0.01) and Select (ADI = 123 × LWT0.716; R2 = 0.84, P < 0.01) pigs. The lack of significant differences for other live and carcass criteria could be explained if the index was favouring individuals with low appetites and reducing the potential for high rates of lean tissue deposition in the Select pigs. Growth of all the pigs from birth to market weight, examined by correlation and regression analyses, suggested that pre-test feeding practices were also limiting the attainment of maximum rates of lean tissue deposition. Key words: Pig, selection index, growth rate, carcass, appetite
Carcass quality characteristics of swine selected for reduced backfat thickness and increased growth rate
Authors: Cliplef R. L. , McKay R. M.
Published: March 2010

Selection for reduced backfat thickness and increased growth rate in Yorkshire (eight generations) and Hampshire (seven generations) swine resulted not only in less backfat but carcasses which were longer with higher percentages of dissectible lean in the fresh hams. Selected carcasses also had a higher incidence of more severe loin lean-fat separation and subjectively perceived softness in the subcutaneous fat. Boar carcasses were longer and leaner with smaller loin eye areas compared with gilt carcasses. Key words: Swine, carcass quality, backfat, growth, selection
Blood, intestinal and skeletal calcium dynamics during egg formation
Authors: Clunies M. , Etches R. J. , Fair C. , Leeson S.
Published: March 2010

An experiment was carried out to study the dynamics of various body-Ca pools in the hen during a single ovulatory cycle. One hundred 32-wk-old Single Comb White Leghorn hens were used. For experimental purposes the ovulatory cycle was divided into four periods: 1–6, 6–12, 12–18 and 18–24 h post-oviposition.At 0, 6, 12 and 18 h post-oviposition 25 hens each were intubated proventricularly with 15 μCi of 45Ca as CaCl2 solution. Approximately 1 mL of blood was collected from the leaf brachial vein, and the bird was subsequently placed in an individual cage. Red blood cells, labelled with 15Cr, were re-injected into the same bird from which it was collected. At 0.5, 1, 2, 4 and 6 h post-intubation with 45Ca, blood samples were taken from the right brachial vein of five hens and the birds were immediately killed, carcasses were dissected, the left femur and tibia-fibula were excised, and an egg, if present, was removed. Whole blood was assayed for 51Cr activity, and plasma, bones and shells were assayed for 45Ca activity and Ca concentration.Another five hens were injected in the right brachial vein with 15 μCi of 45Ca immediately following oviposition. Subsequently, the left brachial vein was catheterized and blood was sampled at 0.5, 1, 2, 4, 6, 12, 18 and 24 h post-injection.There were no significant (P > 0.05) differences in blood volume or plasma-Ca concentration for the four periods assayed. Following intubation, plasma-45Ca activity decreased quadratically (P < 0.05) with time for all four periods assayed. Regression analysis showed that the biological half-life of plasma 45Ca was 3.30, 2.13, 1.80 and 1.77 h for periods 1, 2, 3 and 4 respectively. When birds were injected intravenously with 45Ca the half-life of plasma 45Ca was 0.116 h.There were no significant (P > 0.05) changes over time in ash or Ca content of bone ends (BE) or medullary bone (MB). Only MB accumulated 45Ca during the first 6 h of the cycle. There was no difference (P > 0.05) in 45Ca activity of either BE or MB over time in period 2. Only BE experienced a significant (P < 0.05) loss in 45Ca during period 4.There were no differences (P > 0.05) in total shell ash. shell Ca or 45Ca with time in period 1. Shell ash increased (P < 0.05) by 188, 348 and 237 mg h−1 and shell Ca increased by 69, 128 and 82 mg h−1 in periods 2, 3 and 4, respectively. Accumulation of shell 45Ca confirmed that the transfer of Ca was greatest during period 4 of the ovulatory cycle. Using 45Ca dynamics, we estimated that over the entire ovulatory period 1716 mg of Ca was absorbed from the digestive tract and 1704 mg was secreted as shell. Key words: Calcium-45 activity, calcium-45 half-life; plasma 45Ca, bone 45Ca, shell 45Ca, shell secretion, Ca absorption
Effect of extruding on ruminal disappearance and lower gastrointestinal tract digestion of white lupin seeds
Authors: Kibelolaud A. R. , Vernay M. , Bayourthe C. , Moncoulon R.
Published: March 2010

The effect of extruding white lupin (Lupinus albus 'Lublanc') seeds (WLS) at 110, 130, 150 or 180 °C on the in vitro solubility of crude protein (CP) and in sacco rumen degradation and intestinal digestion of rumen escape CP and fiber was determined. Rumen degradation was estimated by incubating nylon bags in the rumen of cows for 2, 4, 8, 16, 24 and 48 h. Extruding WLS at 110, 130, 150 and 180 °C reduced the CP-solubility by 32.8, 47.7, 58.4 and 67.5%, respectively. The effective ruminal degradabilities of CP, acid detergent fiber (ADF) and neutral detergent fiber (NDF) were evaluated assuming a ruminal outflow rate of 0.06 h−1. Heating WLS at 110, 130, 150 and 180 °C decreased the ruminal degradability of CP value: 89.8, 79.9, 65.1, 61.8 vs. 93.4% (raw), respectively; the corresponding values for ADF and NDF were: 38.4, 35.3, 34.2, 27.6 vs. 43.6% (raw) and 37.7, 33.1, 32.2, 26.5 vs. 39.4% (raw). Postruminal digestion was estimated using a sequence of ruminal in situ incubation for 4, 8 and 16 h, in vitro incubation in an acid-pepsin bath for 3 h and a mobile nylon bag technique distal to the abomasum. Extrusion of WLS decreased the degradability of CP, ADF and NDF in the rumen with a corresponding increase in the amounts digested in the postruminal sections; the whole-tract digestibility was generally unchanged. Therefore, the processing shifted the digestion of these components from rumen to the lower gastrointestinal tract. Key words: White lupin seed, in vitro solubility, rumen degradability, postruminal digestion, crude protein, detergent fiber
Effect of somatotropin on the casein profile and κ-casein glycosylation in milk
Authors: Robitaille G. , Gallo G. F. , Block E.
Published: March 2010

Twenty-nine Holstein cows were used to determine the effects of subcutaneous injections of a placebo (control, n = 9), 10.3 mg d−1 of a recombinant bovine somatotropin (rbST) (n = 10), and 175 mg 14 d−1 rbST in a sustained-release formulation (n = 10) on milk composition, the relative proportions of αs1+s2-casein, β-casein and κ-casein, and the degree of glycosylation of κ-casein. The latter was evaluated by measuring the N-acetylneuraminic acid (NANA) content of casein. Once a week, morning and evening milk samples were collected and composited beginning 4 wk prior to and for 7 wk following the initial injections (105 ± 7 d postpartum). Treatment with rbST increased milk yields (P < 0.06) from 28.4 kg d−1 (control) to 30.6 kg d−1 (daily injections) and 30.9 kg d−1 (biweekly) without affecting percentages of fat, protein and non-fat solids in milk or the relative proportions of the caseins. The NANA content of casein in milk of treated cows (5.6 μg mg−1) was significantly lower (P < 0.05) than in milk from control cows (6.3 μg mg−1). The NANA content of κ-casein was, however, not affected by rbST treatment. Neither the extent of stimulation of milk production due to rbST treatment nor the level of milk production during the treatment significantly affected the NANA content of casein. In conclusion, injection of rbST increased milk yield without affecting degree of κ-casein glycosylation. Key words: Somatotropin, casein, κ-casein glycosylation, lactation
A note on the effect of deep-litter housing on growth performance of growing-finishing pigs
Authors: Matte J. J.
Published: March 2010

Performance of growing-finishing pigs raised on either a partially slatted floor or on deep litter was measured on a group of 60 animals. The body weight gain was depressed on deep litter from 9 to 16 wk of age while an opposite effect was observed from 16 to 20 wk of age (interaction floor × age P ≤ 0.004). Feed conversion did not follow exactly the same trend but tended (P ≤ 0.11) to be improved by deep-litter housing. It appears that the effects observed could mainly be linked to the thermal comfort of the animals. There was no treatment effect (P ≤ 0.16) on carcass measurements at slaughter. Further experiments are necessary to evaluate the appropriate requirements for ventilation and heating when the deep litter system is used in close confinement. Key words: Deep-litter housing, manure enzymes, growth performance, swine
An electronic device to measure the size and degree of packing of the rumen mat in cattle
Authors: Vaage A. S. , Milligan L. P.
Published: March 2010

An electronic device and method for determining the size and degree of packing of the rumen mat in ruminants are described. The mat meter outputs to a chart recorder the distance travelled and the time elapsed for a small weight to ascend through the rumen contents under the constant force of an external weight. From the chart recordings, the rate of ascent (min 100 cm−1) of the weight can be calculated as an index of the degree of packing of the rumen mat in selected strata of the rumen contents. Key words: Rumen mat, mat meter, mat index, voltage divider, cattle
Factors affecting the nutritional value of canola meal: A review
Authors: Bell J. M.
Published: March 2010

In this review canola meal (CM), its nutritionally significant components and the availability of its nutrients to poultry, pigs and cattle were discussed. Avenues for possible improvement in available energy, protein and lysine were identified. Recent findings on glucosinolates were also discussed with the conclusion that a further reduction of glucosinolates through plant breeding is both possible and desirable. The role of the anti-nutrients sinapine, tannins and phytic acid were also considered. The potential impact of improvements to CM on its economic value was examined using linear program least-cost ration formulations applied to typical market situations. Key words: Canola meal, energy, protein, carbohydrates, anti-nutritional factors, economics
Intensively managed pasture in the Great Lakes Basin: A future-oriented review
Authors: Clark E. Ann , Weise Stephan F. , Buchanan-Smith J. G.
Published: March 2010

The contribution of pasture to agriculture in the Great Lakes Basin, and specifically in Ontario, is reviewed from both historical and futuristic perspectives. The ascendency of confinement-based ruminant agriculture is currently under challenge by environmental, societal, and market forces which may favor a less resource intensive approach to livestock feeding. Managing pasture for profitable ruminant productivity represents both opportunities and challenges for contemporary producers, as highlighted with examples from beef, dairy, and sheep research. The premise that research intended to benefit pasture enterprises must incorporate the grazing animal is supported by evidence from several sources, including the comparative performance of livestock grazing alfalfa versus other, less highly bred forage legumes. Emphasis is given to the predominant influence of climatic, soil, and managerial factors on pasture performance, through comparisons of sown and indigenous swards, as well as simple and complex mixtures. It is argued that the contribution of pasture to contemporary agriculture could be enhanced by focusing on alternative selection and management indices, such as stability of nutritional quality with both maturation and temperature, rather than quality per se, vertical profiles in nutrient bulk density in an intact sward, and herbage protein partitioning toward rumen bypass rather than rumen-degradable forms. Research in support of intensively managed pasture must effectively integrate grazing livestock, both as a vehicle to apply realistic stresses against which to test breeding materials and management practices, and as the ultimate indicator of biological and economic response. Key words: Pasture and grazing management, beef, dairy, sheep, alfalfa, bird's-foot trefoil, grass, herbage quality
Linear model evaluations of non-return rates for dairy and beef bulls in Canadian AI
Authors: Doormaal B. J. Van
Published: March 2010

Québec artificial insemination data from 518 609 first inseminations performed by 304 AI technicians in 15 488 herds using semen from 1750 dairy and beef AI bulls were analyzed using a mixed linear model. The effects of month of insemination, age of cow, semen price, breed of service sire, technician and herd were included in an evaluation of service sires for 60- to 90-d non-return rate. Herd was found to be the most important factor influencing service sire mixed model solutions with a standard deviation of solutions of 12.2% non-return rate. Technicians had moderate importance with a standard deviation of solutions of 3.7%. Higher fertility solutions resulted for summer months compared with winter months with the largest difference being 5.18% between December and September. Fertility solutions were highest for virgin heifers and decreased with increasing age of cow. Semen from more expensive bulls generally showed lower solutions than for lower-priced bulls. Dairy breeds, except Jerseys, had lower solutions compared with beef breeds. Service sire solutions were only moderately correlated to unadjusted non-return rates (r = 0.58) therefore indicating the importance of using a linear model approach particularly when several breeds of service sires are represented. Based on correlations among three measures of non-return rate, it was recommended to replace 60- to 90-d non-return rate in Canada by 56-d non-return rate. The mixed linear model procedure used in this study has been adopted by CIAQ and disseminated to other Canadian AI centres for implementation. Key words: Non-return rate, AI, cattle, bulls, technicians
Digestion of soybean globulins, glycinin, α-conglycinin and β-conglycinin in the preruminant and the ruminant calf
Authors: Tukur H. M. , Lallès J. P. , Mathis C. , Caugant I. , Toullec R.
Published: March 2010

Two experiments involving either preruminant (exp. 1) or ruminant (exp. 2) fistulated calves were conducted to study the in vivo digestion of glycinin, α-conglycinin and β-conglycinin from soybean. It was incorporated as a flour (product A, antigenic in vitro) or a protein concentrate (product B, non antigenic in vitro) in milk replacers (exp. 1), or as a meal (product C, antigenic in vitro) in a weaning starter (exp. 2). ELISA detection of residual globulin immunoreactivity was determined on ileal digesta in exp. 1, and on duodenal, ileal and faecal digesta in exp. 2. Ileal flow of glycinin, α-conglycinin and β-conglycinin represented 10.3, 1.2 and 0.9% of corresponding globulin amounts ingested, in the case of product A (exp. 1). Immunoreactive α-conglycinin could only be detected in ileal digesta (1.3% of intake) of calves fed the diet containing product B. In exp. 2, immunoreactive globulins entered the duodenum in low amounts (below 1% of respective intake), especially after weaning. Accordingly, their flow at the ileum and in feces, although measurable, had no meaning from the nutritional point of view. Fermentation in the rumen of weaned calves appeared to be efficient in inactivating most of the potentially harmful dietary constituents. Key words: Soybean, protein, digestion, calf, weaning, glycinin
Repeatability estimates of pelvic diameters measured by Rice pelvimeter in beef heifers
Authors: Paputungan U. , Makarechian M. , Liu M. F.
Published: March 2010

Vertical (VP) and horizontal (HP) pelvic diameters were measured with Rice pelvimeter four times in a 3-wk period by the same operator in 143 bred beef heifers (18 ± 0.5 mo old). Pelvic area (PA) was estimated by VP × HP. Pelvic diameters of 30 open beef heifers (19 ± 0.3 mo old) were also measured by two experienced and two inexperienced operators. Repeatability of pelvic measurements was estimated by the intraclass correlation method. The estimates of repeatability of pelvic measurements were relatively moderate (0.53 ± 0.04, 0.46 ± 0.04 and 0.55 ± 0.04 for VP, HP and PA, respectively), indicating that a single measurement may not provide a reliable estimate of pelvic diameter. Between-operator variance was much smaller than the residual variance for each measurement (0.02 vs. 0.39 for VP, 0.06 vs. 0.36 for HP and 38.15 vs. 276.18 for PA). Key words: Beef heifer, pelvic diameters, repeatability
The influence of sex, feeding and genotype on sodium-potassium ATPase activity in erythrocytes from young dairy calves
Authors: Scollan N. D. , McBride B. W. , Jessop N. S. , Allan G. F. , Oldham J. D.
Published: March 2010

The activity of sodium-potassium ATPase was assessed in erythrocytes from calves of both sexes with either low or high pedigree indices for milk yield. Animals were sampled in both fasted and fed states, and enzyme activity was determined in minimal essential medium ± fetal calf serum. Genotype did not influence enzyme activity, but effects of sex, feeding level and incubation medium were observed. Key words: Calves (dairy), genotype, sodium-potassium ATPase, erythrocyte, sex, incubation medium
Effects of prolonged release recombinant porcine somatotropin and dietary protein on the growth, feed efficiency, carcass yield and meat quality of pigs
Authors: Jones S. D. M. , Schaefer A. L. , Tong A. K. W. , Robertson W. , Holt L. L.
Published: March 2010

The effects of prolonged release recombinant porcine somatotropin (rpST) and dietary protein were tested in 108 Lacombe pigs, allocated to control or rpST treatments at 70 kg and fed isoenergetic diets containing one of three protein levels (14, 17 or 20% CP). Recombinant derived porcine somatotropin was implanted in the ear weekly (Monsanto Agricultural Co., St. Louis, #CP 115409, 12 mg wk−1). The control animals were given a weekly sham injection for a minimum of 4 wk. The prolonged release rpST had no effect on average daily gain (ADG, P > 0.05), but did reduce both the feed:gain ratio (F:G, P < 0.07) and dressing percentage (7 g kg−1 reduction, P < 0.05). Although both the fat thickness (10th rib) and kidney fat were reduced 5.6 and 13.9%, respectively, the absolute organ weights for kidneys, liver, lungs and gastrointestinal tract increased between 5 and 10% in prolonged release rpST treated pigs compared with control pigs (P < 0.05). Bone also increased by 6 g kg−1 (P < 0.05) in prolonged release rpST treated pigs, but carcass muscle or fat proportions were not different. Prolonged release rpST caused a higher ultimate muscle pH, moisture content and shear value (P < 0.06) and lower drip loss and expressable juice (P < 0.05) compared with meat from control carcasses. Increasing the dietary protein had no effect on ADG, but did improve the F:G ratio (P < 0.05). Carcass dressing proportion decreased with increasing protein level, but carcass lean content increased 5 g kg−1 for every 3% increase in crude protein. Simultaneous reductions in carcass fat, marbling and drip loss were observed (P < 0.05) as protein level increased. The data suggest that the current prolonged release rpST (12 mg pellets) shows marginal effects on growth and carcass composition. Some nutrient redirecting was apparent and improvements in the processing value of pork may result. Key words: Porcine somatrotropin, prolonged release, growth, diet, carcass, meat quality
Effect of passive immunization against somatostatin using a high-affinity antiserum on growth, IFG-I and thyroid hormone levels in neonatal lambs reared under warm or cold environmental conditions
Authors: Kessel A. G. Van , Laarveld B.
Published: March 2010

Growth and thyroid hormone levels were recorded following chronic passive immunization against somatostatin (SRIF) in lambs reared under warm or cold environmental conditions. Forty 4-d-old Suffolk lambs (20 male, 20 female), with ewes, were reared outdoors under cold (CLD; −12.1° ± 1.6 °C) conditions or indoors under warm (WRM; 16.7° ± 0.2 °C) conditions. At regular intervals, beginning at birth, lambs in each group were administered (s.c.) ammonium sulphate-purified ovine immunoglobulin raised against ovalbumin (control) or a SRIF-ovalbumin conjugate (anti-SRIF). The anti-SRIF immunoglobulin demonstrated a dissociation constant of 15.9 pM. Lamb weight was recorded and blood samples were harvested at regular intervals from 4 to 25 d of age. Cumulative gain was reduced in CLD lambs at 7 (P < 0.001) and 10 (P < 0.01) d of age. Serum triiodothyronine (T3) was higher (P < 0.02) in CLD lambs from 4 to 20 d of age. SRIF immunoneutralization (25% binding of labelled SRIF at a 1:5000 serum dilution) did not affect lamb growth. Serum T3 was transiently elevated (P < 0.09) in anti-SRIF lambs after exposure to cold. No consistent influence of SRIF immunoneutralization or a cold environment on serum thyroxine (T4), cortisol or insulin-like growth factor I was observed. SRIF immunoneutralization did not enhance growth rate of the rapidly growing lamb reared under warm or cold environmental conditions. Key words: Sheep, somatostatin, immunoneutralization, cold, thyroid, IGF-I
The use of in vivo magnetic resonance imaging and spectroscopy to study porcine stress syndrome in young, halothane-susceptible pigs: Preliminary results
Authors: Janzen Edward G. , Stewart Wendy A. , Towner Rheal A. , Gareau Paula J.
Published: March 2010

Magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) studies on young, halothane-susceptible pigs (4 wk old) are reported. The proton image shows distinct changes in shape of the hindleg muscle as the stress syndrome develops. Simultaneous evaluations of the "free water" content by volume selective spectroscopy shows an increase of about 40% after onset of the syndrome. The in vivo phosphorus spectrum obtained as a function of time before and after the stress event clearly shows a drop in phosphocreatine with simultaneous increase in inorganic phosphate. A drop in pH can also be detected after some delay. This study illustrates the broad applicability of noninvasive MRI and MRS in investigations of porcine stress syndrome. Key words: PSS, porcine stress syndrome, MRI, magnetic resonance imaging, 31P MRS, phosphorus-31 magnetic resonance spectroscopy
Intake of lasalocid-containing mineral supplements by grazing beef heifers
Authors: Rode L. M. , Lysyk T. J. , Beauchemin K. A.
Published: March 2010

A 2-yr grazing study was conducted to determine the effect of lasalocid (BOVATEC) supplement, to yearling beef heifers, on growth rate, reproductive performance and survival of horn fly larvae in feces. Lasalocid was supplemented via a commercially prepared mineral mix offered free-choice. Average daily mineral intake was 83.2 and 89.1, and 140.3 and 147.2 g head−1, for BOVATEC and CONTROL animals, in years 1 and 2, respectively. Mineral intake was unaffected by treatment. The variability in mineral intake was high, as indicated by the large coefficients of variation: 32.1 and 29.1% in year 1 and 29.0 and 38.8% in year 2, for BOVATEC and CONTROL treated animals, respectively. Average daily gain for BOVATEC heifers was 14.5% greater (P = 0.04) than for CONTROL heifers in year 1 even though lasalocid intake was less than the expected level, but only 3% greater (P = 0.51) in year 2. Lasalocid had no significant effect on reproductive performance of heifers or on horn fly larval survival in cattle feces. Horn fly larval survival showed a weak (R = 0.21) and negative relationship with manure nitrogen content. Key words: Mineral consumption, lasalocid, ionophore, pasture, cattle
Use of histochemistry, section-to-slide digestion and image analysis for evaluation of digestibility in reed canarygrass (Phalaris arundinacea L.) genotypes
Authors: Wittenberg K. M. , Thomsett E. C. , Ames N.
Published: March 2010

A useful tool for both nutritionists and plant breeders would be the development of forage quality selection techniques that are simple, rapid and inexpensive. This study evaluates histochemistry, section-to-slide and image analysis techniques for their usefulness in a forage digestibility evaluation program. Digestibility of stem and leaf material for nine parental genotypes of the reed canarygrass (Phalaris arundinacea L.) cultivar Rival were compared using a gravimetric digestion technique. Based on differences observed for stem digestibility, two low- and two high- digestibility genotypes were selected for further study. The four genotypes were harvested for stem material at three stages of growth. Tissues examined included the epidermis (E), cortex (C), phloem (P), sclerenchyma ring (SR), xylem (X), vascular bundles (VB), and parenchyma (PA). Histochemistry staining, using acid phloroglucinol (AP) or chlorine sulphite (CS), indicated genotype and growth stage differences with all tissues except P and X. However, only the AP staining of the SR and PA, and the C with both stains were similar for the two low-digestibility genotypes. Section-to-slide digestion also indicated genotype and growth stage differences, but did not provide similar values for the two low-digestibility genotypes. Tissue area percentages, determined by image analysis, were different among genotypes for P, SR, and PA. A growth stage effect was observed for SR tissue area. The only tissues with similar area percentages for the two low-digestibility genotypes were the PA and SR. The results indicate potential use for histochemistry and image analysis to determine differences in plant stem digestibility. The SR and PA may be the key tissues involved in digestibility differences among genotypes and growth stages. Key words: Forage, digestibility, microanatomy, histochemistry, section-to-slide, image analysis