bluuebunny/crossref_metadata_2025 huggingface dataset:
Melengestrol acetate and estradiol-17β for synchronizing estrus and improving reproductive performance in beef cattle
Authors: Kastelic J. P. , McCartney D. H. , Olson W. O. , Barth A. D. , Mapletoft R. J.
Published: March 2010

Four experiments were conducted to investigate the use of melengesterol acetate (MGA) and estradiol-17β (E-17β) for synchronizing estrus and improving reproductive performance in beef cattle. Synchronized pregnancy rates were higher (P < 0.05) in heifers fed MGA after AI than controls (4 of 9 versus 0 of 7, respectively), but were not different for cows (20 of 37, 54% versus 23 of 40, 58%). Estrus rate (percentage of cows detected in estrus) was higher (P < 0.05) for cows treated with E-17β + MGA compared with those treated with cloprostenol alone (85.0 versus 65.9%). Synchronized pregnancy rates were not significantly affected by feeding MGA or grain only after detected estrus and AI (20 of 31, 64% versus 17 of 30, 57%). For 20 cows not detected in estrus and bred 100 h after cloprostenol treatment, pregnancy rate was higher (P < 0.05) for those fed MGA after AI than controls (6 of 11, 54% versus 1 of 9, 11%). Feeding MGA after breeding may help to improve pregnancy rates. Key words: Melengesterol acetate, estradiol-17β, estrus, reproductive performance, beef cattle
Glycosaminoglycans from growing antlers of wapiti (Cervus elaphus)
Authors: Sunwoo H. H. , Sim L. Y. M. , Nakano T. , Hudson R. J. , Sim J. S.
Published: March 2010

The emerging wapiti industry in North America is based largely on markets for velvet antlers which are used in oriental medicine. Despite the economic opportunity, enthusiasm has been dampened by incomplete understanding of the chemical and pharmacological properties of velvet antler. This study characterizes polysaccharide constituents of glycosaminoglycans in growing antler of wapiti (Cervus elaphus). Glycosaminoglycans were isolated from four sections (tip, upper, middle and base) of growing antlers, and were studied using cellulose acetate electrophoresis, gel electrophoresis, enzymatic digestion and gel chromatography. The tip and upper sections of the antler which are rich in cartilaginous tissues contained chondroitin sulfate as a major glycosaminoglycan with small amounts of hyaluronic acid. In the middle and base sections containing bone and bone marrow, chondroitin sulfate was also a major glycosaminoglycan with small amounts of hyaluronic acid and chondroitinase-ACI resistant materials. More than half of chondroitin sulfate from the middle and base sections had larger molecular size than did the chondroitin sulfates from the tip and upper sections. Key words: Glycosaminoglycans, chondroitin sulfate, antler, wapiti
Effects of production and marketing circumstances on economic values for beef production traits
Authors: Koots K. R. , Gibson J. P.
Published: March 2010

The effect of altering production and marketing circumstances on economic values is quantified for a complete beef production system. Absolute and relative economic values were found to vary substantially with large, but realistic fluctuations in prices and costs. In addition, several examples of different management and different genotypes gave markedly different economic values than in the base situation. Also investigated were the effects of rescaling the enterprise to accommodate three alternative limitations; fixed feed available from pasture, fixed dollars available for feed or fixed amount of beef produced. The effects of rescaling were highly dependent on whether or not fixed costs were accounted for. When fixed costs were ignored (corresponding to a small positive profit) the economic value for mature size decreased while that for fertility increased, but other traits were largely unaffected by rescaling. Overall, production circumstances that reduced survival and fertility yielded the largest changes to economic values. Key words: Economic values, beef cattle, rescaling
Reproductive organ morphology and carcass traits in unselected naturally mating female Bronze turkeys at onset of lay
Authors: Renema R. A. , Melnychuk V. L. , Robinson F. E. , Classen H. L. , Crawford R. D.
Published: March 2010

A study was conducted examining the rates of development of components of the reproductive tract during sexual maturation in a flock of naturally mating Bronze turkeys. Birds were processed at 7-d intervals beginning at photostimulation (29.5 wk of age), for the following 5 wk, and following their first oviposition. The relatively low BW of this strain (6.6 kg) was associated with a very low lipid content (16.4%), abdominal fat pad weight (107 g), and breast muscle weight (1.15 kg). At sexual maturity the ovary contained 12.2 large yellow follicles with 59% of these follicles being in a multiple hierarchy arrangement. There was an average of 1.4 unreconciled POF (the remnant of the site of ovulation). The presence of unreconciled POF suggests that this may be a natural phenomenon in turkeys and not limited to modern fast growing strains. Birds that laid their first egg quickly were more likely to have ovulated several times prior to their first oviposition than birds commencing lay later (r = 0.64; P < 0.02). Regression analysis of reproductive tract development revealed that the oviduct reached its mature weight 3 d earlier than did the ovary (28.3 vs. 31.2 d) (r2 = 0.81; P < 0.0001). This strain resembled modern female line strains in regard to reproductive traits. Key words: Bronze Turkey, body weight, ovary morphology, reproductive disorders
Phytate hydrolysis in pigs fed a barley-rapeseed meal diet treated with Aspergillus niger phytase or steeped with whey
Authors: Skoglund Erika , Näsi Matti , Sandberg Ann-Sofie
Published: March 2010

The degradation of phytate (myo-inositol hexaphosphate) in a barley-rapeseed meal (80:20) diet due to supplemented Aspergillus niger phytase and steeping (soaking at 40 °C for 3 h with feed to water ratio 1 kg:1 L) with whey was studied in eight growing pigs (initial weight 27.8 kg). Phytate and its hydrolysis products (inositol penta-, tetra- and triphosphates, abbreviated IP5, IP4 and IP3) in diets and feces were determined using ion-pair high-performance liquid chromatography (HPLC). Different isomeric forms of inositol tetra- and pentaphosphates were studied utilizing high-performance ion chromatography (HPIC). Supplementing the diet with microbial phytase resulted in a 47% reduction in the amount of fecal phytate. Whey steeping of the diet reduced fecal phytate by 35%. Further reduction of the amount of fecal phytate (64%) was demonstrated in pigs fed the diet both steeped with whey and supplemented with microbial phytase, compared with pigs fed the untreated diet. Identification of IP4 and IP5 isomers in fecal samples showed which kind of phytase enzyme was active during phytate hydrolysis in the digestive tract. From these data, it was concluded that pigs fed the basal or whey steeped diet, without supplemented microbial phytase, had higher relative fecal amounts of DL-Ins(1,2,3,4,5)P5, compared with pigs fed the microbial phytase supplemented diets. Adding microbial phytase to the diet increased the relative amount of DL-Ins(1,2,4,5,6)P5 in feces. With whey steeping of the diet, the relative amount of DL-Ins(1,2,3,4)P4 isomer in feces was increased and the relative amount of DL-Ins(1,2,5,6)P4 isomer was decreased. Key words: Inositol phosphates, steeping, Aspergillus niger phytase, pig
Factors affecting kid survival in five goat breeds
Authors: Perez-Razo M. A. , G. F. F. Sánchez , H. C. Meza
Published: March 2010

Data on 7757 kid's records (2424 Alpine, 1417 Granadina, 2225 Nubian, 1043 Saanen and 648 Toggenburg) were used to study the effect of the breed, sex, litter size, birth weight, dam age, year of birth and birth period (October–January, February, March, April–July) on kid survival rates from 0–15, 16–90 and 91–210 days of age. Survival of kids was in general highest in Granadina and lowest in Toggenburg, while values in the other breeds, tended to be intermediate. Survival in males was lower than in female kids 0–15 and 16–90 d of age (P < 0.001). Kids weighing more than 3 kg at birth had higher survival than those weighing 2 kg or less (P < 0.01). Year and period of birth (P < 0.001) affected all survival rates, and kids born from October to January always showed a higher survival rate than those born from April to July. Breed with birth period, age of dam and birth weight interactions (P < 0.05) indicated a greater sensitivity of Alpines, Saanen and Toggenburg to the above factors. Key words: Goat kids, Alpine, Granadina, Nubian, Saanen, Toggenburg, survival
Influence of supplemental protein quality on rumen fermentation, rumen microbial yield, forestomach digestion, and intestinal amino acid flow in late lactation Holstein cows
Authors: Robinson P. H. , Veira D. M. , Ivan M.
Published: March 2010

The quality of dietary protein for dairy cows is generally assessed based upon the proportion of it which is expected to degrade in the rumen (DIP) vs. that which is expected to escape the rumen undegraded (UIP). However characteristics of dietary proteins can impact the nutritional value of the DIP and UIP. Four lactating Holstein cows were fed a low protein (9.8% CP of DM) ration of 28.6% timothy silage, 27.2% whole crop barley silage, and 44.2% grain-based concentrate (DM basis). This was supplemented with 1.3 kg d−1 of ground barley with either no additional protein supplement, 1.11 kg d−1 of soybean meal, 0.67 kg d−1 of blood meal or 0.20 kg d−1 of urea. All cows were judged to have underperformed relative to expectations, with performance limited by supplies of DIP and/or UIP with all diets. Soybean meal supplementation substantially improved animal performance and measured parameters of N metabolism are consistent with a hypothesis that rumen bacterial growth and outflow, rumen escape of intact dietary protein, and the ability of animal metabolic processes to utilize absorbed energy yielding nutrients for productive purposes were all enhanced. Urea and blood meal supplementation both improved animal performance to a similar extent; although to a lesser degree than soybean meal. Measured parameters of N metabolism suggest that urea stimulated rumen bacterial growth and outflow leading to increased intestinal delivery of protein whereas blood meal supplementation enhanced intestinal delivery of protein due to its very high proportional escape from the forestomachs. Key words: Duodenum, amino acids, protein, protozoa, phosphatidylcholine
Reducing ambient temperature in farrowing houses with a new controlled-environment system
Authors: Farmer C. , Robert S. , Choinière Y.
Published: March 2010

Forty first-parity sows were randomly allocated to a standard (STD; n = 21) or controlled (CET; n = 19) environmental temperature system in the farrowing house. In all cases, heat lamps were installed on one side of the sows, 60 cm from the floor. With the CET system, electronically controlled (EC) heat lamps surrounded by a niche were used. Niches had an acrylic top and three sides of plastic strips that piglets could easily go through. Room temperature was 21 °C with the STD system while it was gradually lowered with CET to attain 15 °C on day 8 postpartum. Within 48 h of birth, litters were standardized to 9 ± 1 pigs. Daily feed and water consumption of sows were recorded as well as growth rate and survival of piglets. Sows' posture and piglets' activity were recorded three times daily throughout lactation. Ambient temperature did not affect (P > 0.1) feed or water intakes of sows during lactation, nor weights or survival of piglets until day 56. From day 2 until weaning (day 23), there was a mean increase of 21% in the frequency of piglets lying in the lamp zone when comparing the CET with the STD system (P < 0.001). A mean increase of 59% in the frequency of piglets being in the lamp zone with the CET system was also noticed from day 8 for active piglets (P < 0.05). Sows were, on average, 77% more active with the CET than with the STD system (P < 0.01) from days 5 to 15 of lactation and the proportion of time they spent lying on the side relative to the total lying time was greater from day 8 until the end of lactation (P < 0.05). In conclusion, gradually decreasing farrowing room temperature to 15 °C has no detrimental effects on the performance of sows and piglets and increases the use of the lamp zone, provided that the environment in this area is well controlled. Key words: Sow, lactation, ambient temperature, farrowing room, behavior, creep heat lamp
Apparent digestibility coefficients of raw ground, acid and fermented silver hake (Merluccius bilinearis) feedstuffs for mink and an evaluation of the storage stability of the silages
Authors: White M. B. , Anderson D. M. , Rouvinen K. I.
Published: March 2010

A 3 × 4 factorial design experiment was conducted to determine digestibility coefficients (DC) of dry matter (DM), crude protein (CP), crude fat (CF), gross energy (GE) and amino acids (AA) in raw ground silver hake (RGSH), acid (ASHS) and fermented (FSHS) silver hake silages for mink. The ASHS was prepared with the addition of 2.5% (wt:wt) formic acid (85% concentration) and 200 ppm antioxidant (ethoxyquin) to the raw ground fish. The FSHS was produced with the addition of 1% Marisil® (Finn Sugar), 15% extruded wheat and 1% (wt:wt) formic acid (conc. 85%) to the raw ground fish. Twelve mature standard type male mink were confined to metabolism cages during the digestibility trial, which consisted of three experimental periods comprised of a 6-d adjustment period, followed by a 5-d collection period. Based on the total collection (TC) method and with graded levels (0, 15, 30 and 45%) of the test feedstuffs in the experimental diets, nutrient digestibilities in the pure feedstuffs were determined using a mathematical regression technique. The apparent digestibility (AD) of DM, CP, CF and GE were RGSH: 88.4, 93.6, 99.2 and 94.7%; ASHS: 90.6, 85.8, 96.1 and 87.2% and FSHS: 77.7, 84.5, 99.2 and 86.1%, respectively. The AD of all the AAs, except proline, in the RGSH was significantly higher (P < 0.05) than that in the ASHS and FSHS. A quality evaluation of the silages was conducted in a completely randomized design with two replications to determine storage stability of the silages, on 10 different sampling days, (3 sampling days for AAs), over the storage period. Quality of the silages was stable up to 90 days for the ASHS and 180 days FSHS based on increases in pH and total volatile nitrogen (TVN) content and decreases in N and AA content. The silver hake feedstuffs would provide a good source of highly digestible nutrients for mink and should be considered as opportunity feeds for these animals. Key words: Apparent digestibility, fish by-products, mink, silage, silage quality, silver hake
Ovarian response after a GnRH challenge in seasonally anestrous ewes
Authors: Rubianes E. , Castro T. de , Ungerfeld R. , Meikle A. , Rivero A.
Published: March 2010

To study the ovarian response of seasonally anestrous Corriedale ewes to a gonadotropin releasing hormone challenge, daily transrectal ultrasonography or laparotomy were performed and luteinizing hormone and progesterone profiles were determined. Of the responding ewes (8/17), three ovulated and formed a healthy corpus luteum and five formed large luteinized follicular cysts that secreted low progesterone levels for 2 to 3 d. Therefore, the study of progesterone profiles alone could lead to erroneous interpretations of the ovarian response to GnRH challenge in sheep. Key words: GnRH, progesterone, ovary, anestrous, ultrasonography, ewes
The effect of dietary vitamin E and controlled atmosphere packaging on the storage life of beef
Authors: Greer G. G. , Jones S. D. M. , Dilts B. D. , Robertson W. M.
Published: March 2010

The effects of dietary vitamin E upon colour, bacteriology and case life of beef was examined following extended storage of longissimus thoracis (LT) muscle in vacuum or in anoxic atmospheres containing 100% CO2 The diets of treated steers were supplemented with 1000 IU of vitamin E animal−1 d−1 for 100 d. Animals were slaughtered in a research abattoir and after 24 h of postmortem aging the LT muscles were removed and assignedto a packaging treatment for storage for up to 11 wk at 2 °C. Rib-eye steaks were cut and displayed under simulated retail conditions to give a surface temperature of 6 °C after storage intervals of 0, 3, 6, 9 and 11 wk. Feeding treatment had no effect (P > 0.05) upon standard carcass and muscle quality traits or bacterial growth but increased carcass α-tocopherol levels from 2.89 µg g−1 in control animals to 5.18 µg g−1 in carcasses supplemented with vitamin E (P < 0.0001). The α-tocopherol concentration in LT muscles was unaffected (P > 0.05) by storage time for up to 11 wk in either packaging treatment. Dietary vitamin E increased a* values and reduced metmyoglobin accumulation after LT storage for up to 11 wk irrespective of package atmosphere. However, dietary vitamin E had no significant effect (P > 0.05) on the colour case life of steaks derived from the LT muscle after vacuum storage for 3 to 11 wk. Contrarily, vitamin E acted synergistically with the CO2 packaging treatment to produce an increase in colour case life from 2.7 (control) to 5.4 d (vitamin E) after 6 wk of LT storage and from 2.4 (control) to 4.0 d (vitamin E) after 9 wk of LT storage (P < 0.0001). In combination with anoxic, CO2 packaging, dietary vitamin E may play a role in assuring beef colour stability following extended periods of storage necessary for fresh beef export. Key words: Vitamin E, packaging, beef storage
Dogfish (Squalus acanthias) and dogfish silage as feed-stuffs in growing-furring diets for mink (Mustela vison)
Authors: Rouvinen K. I. , Anderson D. M. , Alward S. R.
Published: March 2010

A production trial was carried out with 120 mink (Mustela vison) of standard genotype to demonstrate the effects of dogfish (DF) and dogfish silage (DFS) on growth and fur development from weaning until pelting. The experimental treatments were 1) Control, 2) DF15%, 3) DF30%, 4) DF45%, 5) DFS15%, and 6) DFS30%. The test ingredients were used to replace the haddock-herring (35%:10%) mixture in the Control diet at percentage levels indicated by the diet group designation. The rest of the diet was compounded of 10% beef tripe and lungs, 8% poultry offal, 10% cereal, 5% corn gluten meal, 0–2% vegetable oil, 0.4% vitamin-mineral premix and water. All diets guaranteed the females normal body weight gain during the trial. The males receiving the dogfish test diets had significantly poorer growth compared with the males in the Control group. Two males of the DF30% group also developed rickets. The incidence of cotton fur syndrome in the experimental groups was: Control, 0/20; DF15%, 6/20; DF30%, 7/17; DF45%, 0/19; DFS15%, 2/18; and DFS30%, 3/17 pelts produced. Acid ensiling of dogfish was shown to reduce the incidence of cotton fur in the mink but also produced an increased trend in the occurrence of enteritis in the females. Based on the haematology results and tissue iron store analysis, impaired iron metabolism was demonstrated in the DF15-30% and DFS15-30% groups. It can be concluded that the anti-nutritional factor, trimethylamine oxide (TMAO), present in dogfish reduced iron absorption in most of the experimental groups and resulted in disturbances in the fur development of the mink. The absence of cotton fur in the DF45% group is likely due to greater ammonia formation in the feed thus preventing TMAO degradation by triamine oxidase. The improved iron store status in the mink fed the DF45% diet compared with the Control and other dogfish test groups may be explained by the chelating effect of polyamines on iron consequently enhancing its absorption. Key words: Anaemia, cotton fur, trimethylamine oxide, TMAO, nutrition
Nutrient selection by cattle from grass and grass/legume pastures
Authors: Popp J. D. , McCaughey W. P. , Thomas L. R. , Cohen R. D. H.
Published: March 2010

Esophageal fistula and hand-clipped samples were collected from a 32-yr-old crested wheatgrass (Agropyron cristatum L.) pasture and an alfalfa (Medicago sativa L.)/meadow bromegrass (Bromus biebersteinii Roem & Schult.)/Russian wildrye (Psathyrostachys juncea [Fisch.] Nevski) pasture to compare estimates of nutritional quality. Samples were analyzed for crude protein (CP), in vitro digestible organic matter (IVDOM) and selected minerals. Fistula samples had greater (P < 0.05) CP and IVDOM contents than clipped samples at all times except that CP did not differ (P > 0.05) on two occasions and IVDOM did not differ (P > 0.05) on one occasion. Differences in mineral content between clipped and esophageal samples were less consistent, but when they occurred the mineral contents of esophageal samples usually exceeded (P < 0.05) those of clipped samples. We conclude that clipped pasture samples mostly provide biased estimates of the nutritional quality of herbage consumed by cattle grazing grass and grass/legume pastures and should be reported with caution. Key words: Pasture, selection, cattle, protein, digestibility, minerals
The effect of conjugated linoleic acid on fat to lean repartitioning and feed conversion in pigs
Authors: Dugan M. E. R. , Aalhus J. L. , Schaefer A. L. , Kramer J. K. G.
Published: March 2010

The repartioning effect of CLA was evaluated using 108 pigs (54 gilts and 54 barrows) fed from 61.5 to 106 kg liveweight. Pigs were fed a cereal-based basal diet containing either 2% CLA or 2% sunflower oil (a rich source of α-linoleic acid). Irrespective of gender, pigs fed CLA tended to have reduced feed intakes (−5.2%, P = 0.07), improved feed conversion efficiences (−5.9%, P = 0.06) and similar rates of gain relative to sunflower oil fed pigs. In addition, pigs fed CLA deposited less subcutaneous fat (−6.8%, P = 0.01) and gained more lean (+2.3%, P = 0.03) than pigs fed sunflower oil. These data suggest CLA can be used as a repartioning agent in pigs and that further research to optimize the repartitioning effect is warranted. Key words: Pig, pork, swine, conjugated linoleic acid, CLA, repartioning
Analysis of the β-lactoglobulin locus using the grand-daughter design in the Canadian Holstein population
Authors: Aggrey S. E. , Sabour M. P. , Lin C. Y. , Zadworny D. , Kuhnlein U.
Published: March 2010

A total of 185 informative sons from nine heterozygous grandsires were used to study the associations of alleles A and B of the β-LG locus and milk production using the granddaughter design. The average informativeness of the β-LG locus for the nine heterozygous grandsires was 61%. The β-LG locus was found to be significantly associated with milk protein percentage (P ≤ 0.05) across families and (P ≤ 0.01) in one family. The A allele was associated with higher protein percentage EBV (0.096%) than the B allele in that family. There was no association between β-LG and other production traits (milk, fat and protein yields and, fat and percentages). The β-LG locus has a potential use in marker-assisted selection. However, since the association between markers and a given trait is not found in all families, within-family marker selection might be more appropriate due to linkage disequilibrium. Key words: β-lactoglobulin, Canadian Holstein, milk production traits, granddaughter design
Comparison of alfalfa and fenugreek (Trigonella foenum-graecum) silages supplemented with barley grain on performance of growing steers
Authors: Mir Z. , Mir P. S. , Acharya S. N. , Zaman M. S. , Taylor W. G. , Mears G. J. , McAllister T. A. , Goonewardene L. A.
Published: March 2010

To compare nutritive value of alfalfa and fenugreek silages for weaned back-grounding feedlot steers, isonitrogenous diets of alfalfa or fenugreek silage, supplemented with three levels of steam-rolled barley (0, 15 and 30% DM) were fed ad libitum to 60 steers (initial weight of 237 ± 18 kg). The study was conducted in individual pens for 105 d using a 2 × 3 factorial experiment. Fenugreek was cut 17 wk after seeding while the alfalfa was cut at mid-bloom. Both fenugreek and alfalfa silages were prepared in plastic tube silos after wilting to 38 and 35% DM, respectively. After ensiling for 40 d, silage tubes were opened and a feeding trial was conducted. Alfalfa and fenugreek silage contained similar levels of CP (18.0 and 17.2%, respectively) while fenugreek silage contained a lower level of NDF (38.2%) than alfalfa silage (40.4%). Dry matter intake (DMI) and average daily gain (ADG) of steers increased (P < 0.001) and feed efficiency (FE) improved linearly (P < 0.001) with increasing grain level in the diet. Dry matter intake (6.4 vs. 6.2 kg d−1), ADG (0.82 vs. 0.84 kg d−1), FE (8.1 vs. 7.8), total rumen volatile fatty acids (103.4 vs. 105.3 mM), rumen fluid pH (6.9 vs. 6.9) and rumen ammonia concentration (9.6 vs. 10.4 mg dL−1) in steers were similar for both alfalfa- and fenugreek-silage-based diets, respectively. Although in vitro rate of gas production was different at 12.6 and 17.4% h−1 for alfalfa and fenugreek diets, respectively, potential gas production at the end of 72 h of fermentation was similar (21.6 vs. 22.3 mL 100 mg−1 DM). The presence of steroidal saponins in fenugreek plants did not affect steer performance or hormonal status when fed as silage. Results from this study indicate that the nutritive value of fenugreek silage is comparable to that of mid-bloom alfalfa silage, and that fenugreek, a high-DM yielding annual legume, has potential to be a valuable forage in feedlot diets. Key words: Alfalfa silage, fenugreek silage, annual legume, feedlot, steer, barley
Site of exoenzyme action in gastrointestinal tract of broiler chicks
Authors: Boros D. , Marquardt R. R. , Guenter W.
Published: March 2010

The site of exoenzyme action was estimated on the basis of the changes in digesta viscosity, total reducing sugar content and pH in the four sections of digestive tract: crop, gizzard, duodenum and jejunum (anterior small intestine) and ileum from Meckel's diverticulum to colo-cecal junction (posterior small intestine) in broiler chicks fed rye-based diets without and with supplementation of two enzymes and a control wheat-based diet. There was a significant reduction (P < 0.05) in extract viscosity of the digesta taken from the foregut and especially in the posterior small intestine but not from the crop and gizzard of chickens fed the rye-based diet containing added enzyme compared to chicks fed the same diet without enzyme. Also, the higher concentration of readily fermentable reducing sugars (P < 0.05) and the lower pH (P < 0.05) in the digesta of rye-fed compared to wheat-fed chicks was attributable to the higher viscosity of extracts prepared from rye digesta. These results are consistent with the viscosity changes as influenced by enzyme and suggest that the posterior small intestine and to a lesser degree the anterior small intestine are the main sites of action of the exogenous enzymes. Key words: Viscosity, reducing sugar, digesta, enzymes, broilers
Effects of moist heat treatment on crude protein composition and degradability of field peas
Authors: Mustafa A. F. , Christensen D. A. , McKinnon J. J.
Published: March 2010

A study was conducted to determine the effects of moist heat treatment (autoclaving at 127 °C with a steam pressure of 117 kPa) of field peas for 10, 20 and 30 min on crude protein (CP) fractions, in situ ruminal CP degradability and post-ruminal availability of rumen undegraded protein. Heat treatment decreased (P < 0.05) buffer-soluble CP and increased (P < 0.05) the amount of CP associated with the neutral detergent fiber fraction without affecting that associated with acid detergent fiber. Ruminal CP degradability decreased (P < 0.05) while post-ruminal availability of rumen undegraded CP increased (P < 0.05) in cubic fashion as heating time increased. It was concluded that autoclaving of field peas for up to 30 min will reduce ruminal CP degradability without affecting protein quality of rumen undegraded protein. Key words: Pea, heat treatment, ruminal degradability, intestinal availability
Nutritional composition and digestibility by 80-kg to 100-kg pigs of prepress solvent-extracted meals from low glucosinolate Brassica juncea, B. napus and B. rapa seed and of solvent-extracted soybean meal
Authors: Bell J. M. , Tyler R. T. , Rakow G.
Published: March 2010

Seed of Brassica napus canola (cv. AC Excel), B. rapa canola (cv. AC Parkland), and B. juncea canola (line J90-4253) was oil-extracted in a prepress solvent pilot plant. The three canola meals and soybean meal (SBM) (commercial) were fed in four replicates of a digestibility trial to evaluate their digestibility. The meals were mixed with a nutritionally adequate barley-wheat-SBM basal diet at levels of 15 and 30%. Chromic oxide (Cr2O3) was included at 0.5% of the diet as a chemical marker. Eighteen hybrid gilts, approximately 90 kg, were randomized to the first two replicates involving nine diets, including the basal diet, and this allotment was repeated. Brassica juncea meal (air-dry) contained 43.85% crude protein of 82% digestibility and 18.33 MJ kg−1 of gross energy of 71% digestibility. The corresponding values for B. napus AC Excel meal were 41.78, 81, 18.64 and 64; for B. rapa AC Parkland meal 40.05, 79, 18.45 and 71, and for SBM 45.10, 88, 17.28 and 82. Digestible energy values were: B. juncea 13.9, B. napus 13.0, B. rapa 14.1 and SBM 15.9 MJ kg−1. Key words: Canola meal, B. juncea meal, composition, digestibility, pigs
Characterization of body and velvet antler growth in farmed wapiti (Cervus elaphus)
Authors: Goonewardene L. A. , Hudson R. J. , Weingardt R. , Friedel B.
Published: March 2010

The objectives were to study antler and body growth using mathematical models and determine the predictability of antler production. The Richards and Two-phase models fitted the body weight vs. age and antler weight vs. age data equally well (R2 > 95%). Based on Richards', wapiti grew and matured more slowly than cattle. Velvet growth peaked at 7 yr and stags produced 7.8 kg, achieving 91% of their lifetime capacity. Velvet in year 2 depended on the previous years production and stag age (R2 = 86%). Key words: Wapiti, growth rate, prediction models, velvet
The use of corn and barley in diets for veal calves: Effects on performance, diet digestibility and carcass quality
Authors: Noon C. D. , Seoane J. R. , Scott S. L.
Published: March 2010

Forty Holstein bull calves (73.6 ± 6.3 kg) were used in a randomized complete block design to determine if varying the corn-to-barley ratio in the diet affects growth, diet digestibility and carcass quality of grain-fed veal calves. Five diets consisting of corn:barley ratios of 100:0, 75:25, 50:50, 25:75, 0:100 were offered along with a protein supplement (43.6% CP). Grain-to-protein supplement ratios were 2:1, 3.5:1 and 5:1 for the starting, growing and finishing phases, resulting in diets of 23.5, 20.3, and 18.7% CP, respectively. Incidence of diarrhea increased with an increase in dietary barley (P < 0.05). Apparent digestibility of diets decreased as the proportion of barley increased (P < 0.01). Throughout the experiment, DMI was the highest for diets containing 75% barley and the lowest for those containing 100% corn (P < 0.01). Average daily gains behaved in a quadratic manner during the starting phase only (P < 0.01). This effect became linear during the growing and finishing phases, with ADG decreasing as dietary barley increased (P < 0.01). Average feed to gain ratio increased linearly with dietary barley content (P < 0.01). Hot carcass weights and yields decreased linearly with increasing proportions of barley (P < 0.01). Carcass color was not affected by treatments. Carcass classification tended to decrease as dietary barley increased. The results indicate that compared with barley, the use of corn improves performance and diet digestibility of grain-fed veal. Key words: Veal calves, corn, barley, starch digestion, carcass quality
Effects of breed and dietary energy content within breed on growth performance, carcass and chemical composition and beef quality in Hereford and Simmental steers
Authors: Mandell I. B. , Gullett E. A. , Wilton J. W. , Allen O. B. , Kemp R. A.
Published: March 2010

Forty-eight Hereford and 60 Simmental steers were used to evaluate breed differences as affected by dietary energy content on growth performance, carcass and chemical composition, and beef quality. Diets were based on corn silage, alfalfa haylage, whole corn, and SBM and were formulated to provide 2.52 to 2.81 Mcal kg−1 ME and 11.7 to 12.6% protein in the growing phase and 2.69 to 2.86 Mcal kg−1 ME and 9.7 to 10.4% protein in the finishing phase. Low- and high-ener-gy diets were formulated for each breed with the high-energy diet for Hereford serving as the low-energy diet for Simmental. Steers were slaughtered after attaining 8 to 10 mm backfat determined by ultrasound. Higher energy diets increased (P < 0.09) average daily gain (ADG) and feed efficiency within both breeds. Hereford gained more rapidly (P = 0.074) and were more (P = 0.001) efficient in converting feed to gain than Simmental. High-energy diets decreased (P = 0.001) days on feed for both breeds and increased (P = 0.001) carcass weights for Simmental. Otherwise, carcass and chemical composition were generally unaffected by dietary energy content. Simmental were heavier (P = 0.001) and leaner (P = 0.001) than Hereford while marbling classification and intramuscular fat content were similar (P > 0.10) between breeds. While shear force decreased (P = 0.043) feeding the low-energy diet to Simmental, other shear and palatability attributes were unaffected by dietary energy content or breed. Altering dietary energy content for Hereford and Simmental influenced growth performance without affecting carcass and chemical composition and beef quality. Key words: Hereford, Simmental, marbling, shear, palatability, growth performance, carcass
Age-regulated expression of genetic and environmental variation in fitness traits. 1. Genetic effects and variances for egg production in a factorial mating of six selected Leghorn strains
Authors: Liljedahl L.-E. , Fairfull R. W. , Gowe R. S.
Published: March 2010

White Leghorn strains were crossed reciprocally in a complete factorial mating system producing 6 pure strains and 30 strain-crosses, which were kept in individual cages for two laying cycles, 133–496 and 547–909 d of age. The egg production in the second cycle (C2) of the various genotypes started about 10 – 20% lower and had a more linear and less persistent course than in the first cycle (C1). Strains exhibited very different patterns of age changes in both additive and non-additive genetic effects as well as in cytoplasmic effects. The additive autosomal and sex-linked genes (Ai and Zi) active in one laying cycle were quite different from those active in the other laying cycle as shown by low strain genetic correlations between their effects in C1 and C2. Further, the sets of Ai and Zi genes responded with effects quite opposite to each other in both C1 and C2 as indicated by highly negative strain genetic correlations between the Ai and Zi effects. The average non-additive genetic effect of sire strain i or dam strain j over all its crosses with other strains (hi) and the non-additive genetic effect due to the specific combination of genes occurring in each of the two reciprocal crosses between strain i and strain j (sij), showed very divergent patterns of age changes with a conspicuously greater divergence as age advanced. The overall non-additive genetic effect (mean heterosis) increased significantly with age across the two cycles. The strain crosses that most successfully maintained their rate of lay until the end of C2, also most successfully developed a rising age trend for total heterosis. The non-additive genes active in one laying cycle were significantly different from those active in the other laying cycle as shown by the moderately low strain genetic correlations between their effects in C1 and C2. The genotypic variance and its various components increased markedly with age, however, with a tendency to reach a plateau towards the end of both the first and the second laying cycle. The environmental variance increased parallel to the genotypic variance. Consequently, the phenotypic variance followed the same pattern of age changes. The results are discussed in relation to the theoretical aspects of ageing genetics. A model compatible with all the age trends of the genetic and environmental effects and variances is set up, assuming that ageing is composed of two main opposing forces. Finally, the results are briefly discussed from the animal breeding point of view. Key words: Ageing, fitness, laying hens, genetic effects, variation, expression
Trends in milk component production in dairy herds in Ontario: 1985–1994
Authors: Sargeant J. M. , Leslie K. E. , Shoukri M. M. , Martin S. W. , Lissemore K. D.
Published: March 2010

The objectives of this study were to investigate the dynamics of milk component production in dairy herds in Ontario, Canada, over time and to assess the impact of changes to the allocation of milk quota and payment systems on component production. The data consisted of monthly production records from all of the approximately 11 000 farms that shipped milk in Ontario between March 1985 and July 1994.Farm mean yields of milk and milk components have increased over the past decade. The mean fat percentage among the farms increased from 3.85% in 1985 to 3.99% in 1994; protein percentage remained relatively constant at 3.30% in 1985 to 3.32% in 1994. The percentages of protein and fat showed a seasonal pattern. Relatively high component percentages were observed during the fall of each year, and low component percentages were observed during the summer months. Mean fat and protein percentages did not appear to change in response to changes in the allocation of quota or pricing systems. Farms with high (or low) relative protein percentage in one year tended to maintain high (or low) relative protein percentage in the subsequent year, suggesting that herd level factors are related to protein percentage. Key words: Milk components, time trends, dairy
Digestible energy contents and apparent ileal amino acid digestibilities in regular or partial mechanically dehulled canola meal samples fed to growing pigs
Authors: Lange C. F. M. de , Gabert V. M. , Gillis D. , Patience J. F.
Published: March 2010

A study was carried out to determine the influence of partial mechanical tail-end dehulling on apparent ileal amino acid (AA) digestibilities and digestible energy content in canola meal (CM) samples for growing pigs. Twenty Landrace × Yorkshire barrows, with an initial body weight of 35 kg, were fitted with a simple T-cannula at the distal ileum. Digestibilities were determined in 12 experimental diets with observations from five pigs per diet. Five batches of regular CM were obtained from five different crushing plants in Western Canada. A fraction of these batches was partially dehulled. The regular and partially dehulled CM samples were included at 20% in a barley-based diet. One pooled high-fiber CM sample and a straight barley diet were evaluated as well. Partial dehulling increased (P < 0.05) the digestible energy (DE) content from 12.2 to 13.3 MJ kg DM−1, respectively, and the level of crude protein (CP) from 40.6 to 43.8% in regular and partially dehulled CM samples, respectively. The digestibility of threonine was increased (P < 0.05) by partial dehulling, from 72.1 to 75.5%; the digestibilities of CP, lysine, methionine and cysteine were not affected (P > 0.05). Only the digestibilities of methionine and threonine were lower (P < 0.05) in the high-fiber CM sample than in the regular and partially dehulled samples. Digestible energy content, which ranged from 10.8 to 14.2 MJ kg DM−1, differed (P < 0.05) between crushing plants for both regular and partially dehulled CM samples. The digestibility of lysine did not differ (P > 0.05) between processing plants for the regular CM samples. The digestibility of lysine did not differ (P > 0.05) between processing plants for the regular CM samples. In contrast, there were differences (P < 0.05) in lysine digestibility, ranging from 74.8 to 83.8%, and methionine, ranging from 80.4 to 86.9%, between crushing plants for partially dehulled samples. There were low negative relationships between apparent ileal AA digestibilities and NDF, ADF and CF levels (r < 0.39) and between DE content and NDF, ADF and CF levels (r < 0.36) in the CM samples. In conclusion, the reduction in fiber content by mechanical tail-end dehulling increased the supply of DE and the level of CP, but did not influence apparent ileal CP or AA digestibilities, except for threonine which was slightly increased. Key words: Amino acid, canola meal, dehulling, ileal digestibility, pig
Assessment of genetic variability in captive and wild American mink (Mustela vison) using microsatellite markers
Authors: Belliveau A. M. , Farid A. , O'Connell M. , Wright J. M.
Published: March 2010

The genetic variability of 212 black mink from four ranches, and 20 each from wild mink trapped in Eastern Canada, pastel and brown (wild-type) was assessed using seven microsatellite loci. The average number of alleles per locus and expected heterozygosity (HE) in the entire sample were 6.57 and 0.63, respectively. The estimates of HE were comparable among the black mink herds (0.53 to 0.61), and between black and the wild mink (0.50), indicating a considerable level of genetic variability within black mink, despite high levels of uniformity that have been achieved in fur quality traits as a result of many years of intense selection. Brown mink had the highest HE among populations (0.65), which could be the cause or the effect of their higher vigor and reproductive performance compared with the black mink. All the populations showed a higher level of homozygosity than expected from the Hardy-Weinberg (H–W) proportions at several loci (positive FIS), perhaps as a result of linebreeding and positive assortative mating commonly used in the mink industry. Excess of homozygosity in the wild mink may indicate breeding between related individuals occupying adjacent territories, and a limited movement of mink in the wild. The black mink herds were closely related to each other, as were the pastel and brown. Gene flow from common sources to all the herds and infusion of the Jetblack allele into all the ranches were likely the causes of relatedness of the black mink herds. The black mink herds were more closely related to the wild mink than to the colored mink. This panel of microsatellites correctly classified black and nonblack mink into their respective groups with 91 to 97% accuracy. Between 70 and 88% of the black mink were correctly assigned into their herd of origin. Key words: Mink, genetic variability, genetic distance, microsatellites
Effect of maceration on nitrogen fractions in hay and silage
Authors: Agbossamey Y. R. , Savoie P. , Seoane J. R.
Published: March 2010

An intensive mechanical conditioning treatment, referred to as maceration, was applied at mowing to alfalfa or timothy in order to enhance drying rate, reduce wilting time and possibly reduce respiration losses and proteolysis. In 1995, a laboratory trial was conducted using two levels of force (1750 and 3500 Newton) and five levels of conditioning: a control (no conditioning), one passage, three passages, five passages and seven passages through two steel knurled rolls. All forages were dried in a controlled environment at 30 °C and conserved as hay. The level of force did not affect the chemical composition of the forages obtained. However the nitrogen (N) fractions were affected by the level of maceration. As the level of conditioning increased, the soluble N fractions (A and B1) of both forages decreased (P < 0.001). Meanwhile, the slowly degradable N fraction (B3) increased linearly (P < 0.001) in timothy and quadratically (P < 0.003) in alfalfa. The fraction of unavailable N (fraction C) also increased linearly (P < 0.01) with intensity of maceration. In 1996, alfalfa was conditioned in the field at four intensity levels: a control (rubber roll-conditioning), one passage, two passages, and three passages through a full-size mower-macerator with three knurled rolls. The alfalfa dried under poor climatic conditions with alternating rain and sunshine and was conserved as silage at 30% dry matter (DM) after a 40-h wilt or as hay after a 90-h wilt. Neutral detergent fibre (NDF), acid detergent fibre (ADF), and ash contents increased linearly (P < 0.001) with the level of maceration; the increase was greater in hay than in silage. The non protein nitrogen (fraction A) decreased (P < 0.001) while fraction B3 and unavailable N (fraction C) increased (P < 0.001) with level of maceration. The results suggest that maceration decreases the extent of proteolysis during conservation and preserves a higher proportion of the slowly degradable N (escape nitrogen). Key words: Forage, maceration, chemical composition, nitrogen fractions
Ruminal degradability of alfalfa and corn after processing or maceration
Authors: Savoie P. , Tremblay G. F. , Petit H. V.
Published: March 2010

The effects of mechanical treatment on ruminal degradability of alfalfa and corn were determined in three experiments using nylon bags incubated in the rumen of two fistulated dry cows. The first experiment was a 2 × 2 × 2 factorial design applied to chopped alfalfa at two levels of mechanical treatment (processing with two corrugated rolls in a forage harvester or no processing), two throughput rates (medium or high) and two moisture contents (after a 4-h or a 24-h field wilting period prior to processing). The second experiment was a 2 × 2 factorial design applied to chopped corn at two levels of mechanical treatment (processed or not) and two throughput rates (medium or high). In these two experiments, forages were immediately frozen (not fermented) for later degradability measurements. In the third experiment, alfalfa was mowed either with a conventional mower-windrower or an experimental mower-macerator with three corrugated rolls. After 40 h of field wilting, alfalfa was dehydrated and processed into pellets. In the first experiment (chopped and frozen alfalfa), throughput, processing and wilting period had no effect (P > 0.05) on the effective degradability of DM, CP, NDF and ADF. In the second experiment, DM degradability of chopped corn decreased with an increased throughput (46.4% vs. 43.7%) but increased with processing (43.9% vs. 46.2%). Processing also increased CP degradability of corn. In the third experiment, maceration with subsequent field wilting during 40 h and dehydration produced alfalfa pellets with a higher degradability of DM (56.0% vs. 50.4%) and of NDF (27.1% vs. 17.3%) than pellets from non-macerated alfalfa. These results suggest that the increase in ruminal degradability is greater with alfalfa macerated and wilted in the field (exp. 3) than with alfalfa frozen immediately after harvesting and processing (exp. 1). Maceration probably reduced the loss of nutrients by decreasing field respiration. Processing of corn may have increased the ruminal degradability because of increased kernel breakage that facilitated starch digestion. Key words: Maceration, crop processing, ruminal degradability, alfalfa, corn