bluuebunny/crossref_metadata_2025 huggingface dataset:
IMPACT OF A 1;29 ROBERTSONIAN TRANSLOCATION ON A HERD OF PUREBRED BEEF CATTLE
Authors: SCHMUTZ SHEILA M. , MOKER JANE
Published: March 2010

This paper examines the spread and influence of a 1;29 Robertsonian translocation in a purebred beef herd. An entire herd of 94 Charolais cattle has been karyotyped since discovery of a 1;29 Robertsonian translocation in two yearling bulls entered in the Saskatoon R.O.P. bull test station in 1987. The translocation was inherited through their maternal grandfather. Approximately 46% (43) of the 94 cattle karyotyped possessed this translocation, including one cow which had two copies (58, XX, tt). The test herd consisted of 59 cows, 4 bulls, and 31 calves with 27, 2, and 14 animals affected respectively. In addition one cow with an additional X chromosome was detected (61, XXX). The overall fertility of this herd had been low but alterations in management practices lessened the negative impact. Prolonged bull exposure, first exposure of females at 2 y of age, and continued surveillance of cows returning to heat followed by rebreeding ensured that most cows did produce calves in most years. However, although such practices reduced the culling rate, they maintained the translocation carrier cows in the herd. Key words: Beef cattle, translocation, embryonic loss, subfertility
THE APPARENT DIGESTIBILITIES OF DRY MATTER, ORGANIC MATTER AND NONAMMONIA NITROGEN IN THE FORESTOMACH, SMALL INTESTINE, AND LARGE INTESTINE OF WETHERS EXPOSED TO A COLD ENVIRONMENT
Authors: KELLY J. M. , CHRISTOPHERSON R. J.
Published: March 2010

Eight shorn yearling Suffolk wethers cannulated in the rumen, abomasum, and terminal ileum were exposed to temperatures of 0 to + 2 °C or 21–25 °C in a crossover experiment to determine effects on the apparent digestibilities of dry matter (DM), organic matter (OM) and nonammonia nitrogen (NAN) in the forestomach and small intestine. Animals were housed in metabolic crates and fed 1600 g d−1 chopped bromegrass hay. After 30 d acclimation, feed, ruminal, abomasal, terminal ileal and fecal samples were acquired for the determination of DM, OM, cell wall constituents (CWC), acid detergent fiber (ADF) and NAN. Rumen volatile fatty acid composition was also determined. Digesta flows at the abomasum and terminal ileum were estimated from the dilution of 103ruthenium-phenanthroline and 51chromium-EDTA during continuous infusion of these markers into the rumen. Dry matter (P < 0.10), OM (P < 0.05) and NAN (P < 0.05) flows to the abomasum were increased during cold exposure. The apparent digestibilities of DM (P < 0.10), OM (P < 0.05) and NAN (P < 0.05) in the rumen were decreased during cold exposure but the apparent digestibilities of these components did not change in the small intestine. Consequently, during cold exposure the proportion of OM and NAN digested in the small intestine relative to OM digested in the entire gastrointestinal tract was increased. Total ruminal VF A concentration was not affected by temperature; however, the molar proportion of acetate declined (P < 0.05) and that of propionate increased (P < 0.01). This, together with a greater proportion of the digestion taking place in the small intestine, may improve the efficiency of utilization of metabolizable energy and partly compensate for the decreased ruminal digestion of OM during cold exposure. Key words: Organic matter, nitrogen, digestion, sheep, cold environment
INFLUENCE OF BREED OF SIRE, DIETARY INTAKE AND HOUSING FACILITIES ON THE ATTAINMENT OF PUBERTY IN CROSSBRED GILTS
Authors: DYCK G. W.
Published: March 2010

The role of diet intake and type of confinement pen in the stimulation of puberty was determined with 483 gilts from a Landrace (L) × Yorkshire (Y) rotational cross over 4 yr. At 160 d of age, gilts were housed either in stalls (S) or groups (G) of eight per pen. They were fed a diet intake level to provide approximately 0.4 kg gain d−1 for the duration of the experiment (C) or 0.0 kg d−1 for the first 2 wk (R) and then as for C. Gilts were checked for estrus once daily with vasectomized boars. AU S gilts had 30 min d−1 of in-pen exposure to mature boars, while G gilts had constant pen line exposure to mature boars. Over the 8-wk period 73.5% of the gilts attained puberty. Diet intake restriction and group penning had similar effects on the mean interval to puberty, with C and R gilts averaging 13.6 ± 1.0 and 17.4 ± 1.0 d (P < 0.01), and S and G gilts averaging 12.3 ± 0.9 and 18.7 ± 1.1 d (P < 0.01). Both the Rand G treatments resulted in a delay in the attainment of puberty as compared to S-penned C gilts. This difference was apparent within 3 d. The delay in puberty associated with diet intake restriction was found only in S-penned gilts and was eliminated 10 d after the R gilts were placed on the C level of diet intake. The group penning delay in attaining puberty was evident for 31 d in Y-sired gilts and to the end of the experiment in L-sired gilts. In L-sired gilts 85.3 and 55.6% of the S and G gilts, respectively, attained puberty (P < 0.05) as compared to 74.6 and 76.9% of the Y-sired gilts. Thus, the ability of the gilt to attain puberty in response to boar exposure is dependent on the breed of gilt, diet intake and pen type, with stalls and an adequate growth rate required for the greatest response. Key words: Gilts, puberty, breed, diet intake, pen type
EFFECT OF TANNIN CONTENT IN TWO ISOSYNTHETIC STRAINS OF BIRDSFOOT TREFOIL (Lotus corniculatus L.) ON FEED DIGESTIBILITY AND RUMEN FLUID COMPOSITION IN SHEEP
Authors: CHIQUETTE J. , CHENG K.-J. , RODE L. M. , MILLIGAN L. P.
Published: March 2010

Low tannin (LT) and high tannin (HT) isosynthetic strains of birdsfoot trefoil containing 1 and 3% condensed tannins on a dry matter (DM) basis were cut fresh daily and fed to eight ruminally cannulated Suffolk wethers. Rumen fluid samples were collected before feeding and 3 and 6 h after feeding for pH, chlorophyll, supernatant protein nitrogen (N), ammonia nitrogen (NH3-N) and volatile fatty acids (VFA) determinations, and protozoa counts. Daily samples of the forage fed to the animals, and of feces, were analyzed for crude protein (CP) content, acid detergent fiber (ADF) and organic matter (OM). Results from rumen fluid analyses indicated that sheep receiving the HT strain had lower (P < 0.01) supernatant protein N and NH3-N concentrations, and consistently but not significantly lower VFA and chlorophyll concentrations. Animals fed HT showed higher (P < 0.05) protozoa counts than LT-fed animals, but only in the samples taken 3 h postfeeding. Ruminal pH was similar on LT and HT diets. Apparent digestibility of CP was 9% less (P < 0.05) in sheep fed the HT strain. However, apparent digestibilities of DM, OM and ADF were not affected by the tannin level. Key words: Lotus corniculatus L., birdsfoot trefoil, tannin, digestibility, rumen, sheep
FACTORS AFFECTING GESTATION LENGTH IN ONTARIO HOLSTEINS
Authors: NADARAJAH K. , BURNSIDE E. B. , SCHAEFFER L. R.
Published: March 2010

The mean gestation length of an Ontario Holstein population was 281.3 ± 6.0 d. Parity, sex of calf, cow size and size of calf were associated with variation in gestation length. Heritability estimates calculated from sire of the calf and maternal grand-sire of the calf variance components were 0.33 and 0.06, respectively. Genetic correlation between direct and maternal effects for gestation length was negative and low (−0.27). Key words: Gestation length, direct and maternal effects, heritability
THE EFFECT OF STAGE OF MATURITY ON THE NUTRITIVE VALUE OF KOCHIA
Authors: KNIPFEL J. E. , KERNAN J. A. , COXWORTH E. C. , COHEN R. D. H.
Published: March 2010

A trial was conducted to determine the nutritive value for sheep of kochia (Kochia scoparia L. Schrad) grown on saline soil and harvested at the early seed stage and the full bloom stage of maturity. There was a significant decrease in digestible organic matter intake (DOMI) and digestible crude protein intake (DCPI) with increasing kochia maturity (31.6 vs. 23.2 g DOMI kg−0.75 (SE = 0.6; P < 0.05) and 4.22 vs. 1.41 g DCPI kg−0.75 (SE < 0.001; P < 0.05)). Early cut kochia appears to be at least equivalent in digestible energy to alfalfa, but lower in digestible protein. Key words: Kochia, maturity, nutritive value, sheep
MUSCLE AND RECTAL TEMPERATURE RESPONSE CURVES TO A SHORT-TERM HALOTHANE CHALLENGE IN EIGHT-WEEK-OLD PIGLETS WITH KNOWN GENOTYPE AT THE HALOTHANE LOCUS
Authors: SATHER A. P. , SCHAEFER A. L. , TONG A. K. W. , GARIÉPY C. , ZAWADSKI S. M.
Published: March 2010

Each of the three genotypes (NN: normal, halothane negative; Nn: carrier, halothane negative; nn: halothane sensitive) at the halothane locus had a significantly different muscle temperature response curve to a 3-min halothane challenge, while only halothane positive (H+) and negative H−) phenotypes could be distinguished on the basis of the rectal temperature response curves. However, the among animal variation precludes its use as a diagnostic tool for the identification of heterozygous and homozygous normal among halothane negative pigs. Key words: Temperature, halothane gene, swine, genotype
PREWEANING PERFORMANCE OF CALVES FROM FIRST-CROSS AND RECIPROCAL BACKCROSS COWS
Authors: McKAY R. M. , RAHNEFELD G. W. , WEISS G. M. , FREDEEN H. T. , NEWMAN J. A. , LAWSON J. E. , BAILEY D. R. C.
Published: March 2010

Preweaning performance was evaluated for calves out of first-cross and reciprocal back-cross cows maintained under two contrasting environments. All cows were bred to Limousin bulls and the calves were born between 1982 and 1986, inclusive, at Brandon, Manitoba (semi-intensive management) and Manyberries, Alberta (extensive range management). Dam cross comparisons revealed that calves out of Hereford × Angus dams were inferior to calves out of European continental × British dams for all preweaning traits at both locations. Comparisons between calves out of F1 dams and calves out of backcross (1/4 or 3/4 European continental) dams generally favored the calves out of F1 females. Specific and nonspecific comparisons between the reciprocal backcrosses demonstrated that calves out of dams with 3/4 European continental breeding were heavier and grew faster than calves out of dams with 1/4 European continental breeding. Male calves exceeded female calves for all preweaning traits and calves born at Manyberries were heavier and grew faster than calves born at Brandon. Key words: Beef cattle, preweaning growth, crossbreeding, backcrosses
CALVING EASE AND CALF MORTALITY IN FIRST-CROSS AND BACKCROSS COWS
Authors: McKAY R. M. , RAHNEFELD G. W. , WEISS G. M. , FREDEEN H. T. , NEWMAN J. A. , LAWSON J. E. , BAILEY D. R. C.
Published: March 2010

Calving ease and calf mortality were evaluated for calves out of first-cross and backcross cows maintained under two contrasting environments. All calves were sired by Limousin bulls. The dam crosses at Brandon were HA, SN, CN, ACA, CCA, ASA, SSA, HCH, CCH, HSH, SSH, NCN, CCN, SSN, and NSN with H = Hereford, A = Angus, N = Shorthorn, C = Charolais, S = Simmental and a SSA cross was 3/4 Simmental-1/4 Angus. At Manyberries the dam crosses were HA, SN, ASA, SSA, HSH, SSH, NSN, and SSN. The calves were born between 1982 and 1986, inclusive, at Brandon, Manitoba (semi-intensive management) and Manyberries, Alberta (extensive range management). At Brandon, when calf birth weight was not a covariate, the significant dam cross contrasts for calving ease included less difficulty for SN cows than either the SSN or NSN cows, and for 3/4 A-1/4 European continental (E) cows than 1/4A–3/4E cows. When adjusted to a common calf birth weight the significant contrasts were HA cows had more difficulty than SN cows and the combination of SN and CN cows, SN cows had less difficulty than NSN cows, and 3/4A–1/4E cows had less difficulty than 1/4A–3/4E cows. At Manyberries, regardless of whether calf birth weight was excluded or included as a covariate, the SN cows had less difficulty than the SSN and the SSN cows had less difficulty than NSN cows. No significant dam cross comparisons were observed for calf mortality scores. Adjusting the calving ease scores to a constant calf birth weight did not significantly alter the magnitude of the contrasts but it did shift their probability levels. Location and sex of calf effects were not significant except for calving ease at Brandon where more difficulty was associated with male calves than female calves. Key words: Beef cattle, crossbreeding, backcrosses, calving, mortality
THE EFFECT OF A PROGRESSIVE-RESISTANCE EXERCISE ON GROWTH, DEVELOPMENT AND MEAT QUALITY OF SHEEP
Authors: AALHUS J. L. , PRICE M. A.
Published: March 2010

This study was conducted to determine the effect of a progressive-resistance jumping exercise on growth, development and meat quality in sheep. Exercised sheep did not differ from control sheep in their live animal performance or in the proportion of muscle, fat and bone in the carcass, indicating the low energy cost of this exercise. The use of platform jumps rather than hurdle jumps resulted in a significant contribution of muscles in the forelimbs to the jumping motion. As a result, flexors of the elbow joint were a significantly larger proportion of total muscle weight in the exercised sheep. Muscle samples from the vastus lateralis in exercised sheep had lower Warner-Bratzler shear (P = 0.09) and Kramer Press-Ground (P = 0.04) scores than their control counterparts. The reason for the increased tenderness as a result of exercise is unknown, but there was no evidence that it resulted from muscular hypertrophy. Key words: Sheep, exercise, body composition, tissue distribution, meat quality
THE EFFECTS OF ENDURANCE EXERCISE ON LIVE ANIMAL PERFORMANCE AND CARCASS GROWTH AND DEVELOPMENT IN SHEEP
Authors: AALHUS J. L. , PRICE M. A.
Published: March 2010

This study was undertaken to separate the effects of an endurance exercise from normal growth on live animal performance and body composition in growing sheep. To ensure similar exercise intensities among the sheep, training levels were set at 75% of VO2max. As the length of time on trial increased, pre-exercise resting oxygen consumption decreased significantly (P = 0.008). Exercised sheep consumed more feed but grew at the same rate as their control counterparts. There were no changes in the proportion of muscle, fat or bone as a result of the endurance exercise. However, exercised sheep tended to have a higher proportion of muscle in the proximal pelvic limb (P = 0.02) and in the abdominal wall (P = 0.06). Exercised sheep had a lower proportion of chemically determined intramuscular fat in the semimembranosus after 12 wk and in the vastus lateralis and gastrocnemius after 18 wk of exercise. Key words: Endurance exercise, sheep, body composition, oxygen consumption, muscle distribution
PUBERTAL DEVELOPMENT OF RAM LAMBS: REPRODUCTIVE HORMONE CONCENTRATIONS AS INDICES OF POSTPUBERTAL REPRODUCTIVE FUNCTION
Authors: YARNEY T. A. , SANFORD L. M.
Published: March 2010

Pubertal changes in blood serum concentrations of LH, FSH, PRL and testosterone were determined for 14 Suffolk rams born in March, and related to their postpubertal reproductive function. Blood samples were taken from the jugular vein (20-min intervals for 6 h) every 20 d and scrotal circumference and testicular diameter (TD) were measured every 10 d between the ages of 30 and 190 d, and at 13 and 17 mo. Daily sperm output (DSO, sperm voided in urine) or semen quality, and libido were assessed at about 6, 13 and 17 mo of age. LH-pulse magnitude increased between 30 and 70 d of age and then declined progressively to adult values; pulses occurred most frequently at 110 and 190 d of age, and at 17 mo. Mean concentrations of FSH, PRL and testosterone were highest at 50, 90 and 190 d of age, respectively, and changed normally with season when the rams were yearlings. Mean testosterone concentration at 50 d was related (P < 0.05) to testicular size (r ≥ 0.57) at all postpubertal ages and to ejaculation frequency (EF) (r = 0.82) at 6 mo and DSO (r = 0.78) at 13 mo. Mean and baseline concentrations of LH at 50 d were related (r ≥ 0.55, P < 0.05) to TD and DSO at 6 and 13 mo of age, and to EF at 6 mo. The strongest relationships (r ≥ 0.67, P < 0.01) were between mean testosterone concentration at 150 d and testicular size and sperm output at all postpubertal ages. Testicular size and spermatogenic function in yearling Suffolk rams relate to serum LH and(or) testosterone concentrations in the neonatal period (50 d) and at puberty (150 d). Key words: Sexual maturation, reproductive traits, interrelationships, ram
EFFECTS OF CHANGES IN ATTRIBUTES OF RETICULAR CONTRACTION ON FECAL PARTICLE SIZES IN CATTLE
Authors: OKINE E. K. , MATHISON G. W. , HARDIN R. T.
Published: March 2010

A 3 × 3 Latin square design experiment was conducted with three ruminally-cannulated Hereford steers (605 ± SD 98 kg) to determine the effects of changes in reticular contraction characteristics on the distribution of fecal particle size of cattle fed at maintenance. Addition of 0 (control; C) 9 (low weight; LW) or 18 (high weight; HW) kg weight to ventral sac of the rumen of steers linearly increased (P = 0.03) the geometric mean size of fecal particles. During the 1.5-h feeding period, duration and amplitude of reticular contractions linearly increased (P = 0.04) and decreased (P = 0.08), respectively, with the addition of weights. Frequency of reticular contractions increased linearly (P = 0.05) and quadratically (P = 0.07), reaching a maximum of 1.7 min−1 in LW steers, 1.6 min−1 and 1.4 min−1 in HW and C steers, respectively. Duration of reticular contractions, but not amplitude or frequency, was linearly related to the proportion of large particles and to the geometric mean size of fecal particles (r = 0.90, P = 0.002; and r = 0.61, P = 0.08, respectively). It was concluded that the increase in fecal geometric mean and the change in the distribution of fecal particle sizes with increasing weights in the rumen was associated with increases in the duration of reticular contractions rather than changes in frequency or amplitude. Key words: Steers, reticular contractions, fecal particle size, rumen, weight
BIRTH WEIGHT IN CALVES AND ITS RELATION TO GROWTH RATES FROM BIRTH TO WEANING AND WEANING TO SLAUGHTER
Authors: BAILEY C. B. , MEARS G. J.
Published: March 2010

Holstein steers and Hereford and Angus bulls were separated from their dams at 2 d of age and supplied fixed amounts of energy in relation to live weight between birth and 100 kg liveweight. Within individuals, relative weight gain (g kg−1 d−1) was constant between birth and weaning at 100 kg, and was taken as a measure of inherent growth efficiency. Constancy of relative weight gain indicates that the weight of body substance deposited daily is proportional to the weight of the growing mass. As a consequence, the smaller the birth weight, the lower the absolute daily gain at any given age up to weaning. Variations in birth weight and relative weight gain before weaning were together shown to account for nearly all the variance in absolute weight gain, and variation in birth weight per se was responsible for between 36 and 60% of it. The Hereford and Angus bulls were supplied uniform amounts of energy in relation to liveweight from 100 to 500 kg liveweight, when they were slaughtered. Birth weight was positively correlated with post-weaning daily weight gain and negatively with both energetic efficiency of weight gain and the proportion of fat in the carcass gain. It appeared that these relationships were the result of an association between birth weight and mature weight since, over any fixed weight interval, cattle of large mature size gain faster, and deposit less fat, than cattle of small mature size. Key words: Birth weight, growth, efficiency, cattle
EFFECT OF FEED TEMPERATURE ON COLD SUSCEPTIBILITY OF CATTLE AND SHEEP
Authors: NICOL A. M. , YOUNG B. A.
Published: March 2010

The metabolic heat production of steers was measured at ambient temperatures of +10, −8 and −20 °C following their consumption of 15-kg turnip bulbs (Brassica napus) with a temperature of 27, 2 or −8 °C, or 10-kg turnips with a temperature of 2 °C followed by 1 kg hay. Metabolic heat production was elevated 13–80% after eating the cold and frozen turnips when steers were exposed to −8 °C and 35–80% when exposed to −20 °C. Sheep fed 20, 35, 55, 80 and 110 g pelleted ration per kg−0.75 d−1, accompanied by a ruminal infusion of water at 38 or 2 °C at a volume required to simulate a 10% dry matter feed had their metabolic heat production measured at +10 and −20 °C. Heat production was significantly increased at −20 °C for only the 2 °C infusion although with the 38 °C infusion at the lower feed intake levels, metabolic heat production was higher by up to 37% at an ambient temperature of −20 °C than at +10 °C. The lower critical temperature of the steers after ingestion of the turnips was estimated to be −4.5, −2.4, +3.2 and +13.9 °C forthe27, 2 + hay, 2 and −8 °C turnips, respectively. The lower critical temperature of sheep was raised by 1, 11, 31, 25 and > 22 °C by the ruminal infusion of water at 2 °C compared to water at 38 °C in sheep fed 20, 35, 55, 80 and 110 g feed kg−0.75 d−1, respectively. Key words: Cold, temperature, heat production, cattle, sheep
METABOLISM IN ADIPOSE TISSUE AND MUSCLE OF THE YOUNG PIG
Authors: ADEOLA O. , McBRIDE B. W. , BALL R. O. , YOUNG L. G.
Published: March 2010

Subcutaneous adipose tissue and intercostal and sartorius muscles from five barrows and five gilts at 20 kg liveweight were used to study lipogenesis, lipolysis, Na+, K+-ATPase-dependent respiration and protein synthesis. Lipogenesis rate measured by 14C-acetate incorporation into lipid was similar between barrows and gilts; and 100 μg insulin per mL enhanced (P < 0.1) subcutaneous adipose tissue lipogenesis by 74%. Lipolysis rate quantitated by glycerol release was similar between barrows and gilts (3546 and 4160 nmol g−1 2 h−1). Adenosine deaminase and norepinephrine together enhanced adipose tissue lipolytic response by 102%. Fractional and absolute rates of protein synthesis were similar between barrows and gilts (3.24 and 3.69% d−1; 6.01 and 6.06 mg g−1 d−1); and between intercostal and sartorius muscles. Barrows had lower Na+, K+-ATPase-dependent respiration than gilts and the maintenance of Na+ and K+ transmembrane ionic gradient in the muscle preparations accounted for 23–26% of total respiration. Key words: Pigs, adipose tissue, skeletal muscle, metabolism
ACTIVE IMMUNIZATION AGAINST SOMATOSTATIN IN GESTATING GILTS AND THE EFFECT OF TRANSFERRED IMMUNITY ON PIGLETS
Authors: FARMER C. , PELLETIER G. , PETITCLERC D. , DUBREUIL P. , BRAZEAU P.
Published: March 2010

Seventeen Yorkshire gilts were immunized four times during gestation against somatostatin (SRIF-IMM; n = 9) or its conjugated protein (BSA-IMM; n = 8). Colostrum and blood samples were collected from sows at parturition and blood samples were collected from piglets before initial suckling. Thereafter, blood and milk samples were withdrawn weekly from sows and piglets. Four piglets per litter received a s.c. injection of 15 μg kg−1 B.W. of porcine growth hormone-releasing factor (pGRF) (1–29)NH2 on days 1, 7, 14, 21 and 27 postpartum. Blood samples were obtained immediately before and at 20 and 40 min after injection. Newborn piglets passively acquired immunity against somatostatin through ingestion of colostrum. Before initial suckling, piglets from SRIF-IMM sows had greater (P < 0.05) circulating levels of glucose (4.01 ± 0.17 vs. 2.92 ± 0.12 mmol L−1) and free fatty acids (90.61 ± 4.36 vs. 63.11 ± 4.28 μeq L−1) but lower (P < 0.05) growth hormone (GH; 109.4 ± 8.1 vs. 146.6 ± 7.0 ng mL−1) concentrations than control piglets. However, insulin-like growth factor I levels and birth weight were unchanged (P > 0.05). The endogenous GH levels as well as the GRF-induced GH levels in piglets between 1 and 27 d postpartum were not affected by immunization but were affected by age, with 1-day-old piglets showing the greatest response to GRF. In conclusion, there is passive transfer of immunity against SRIF via the colostrum in swine and piglets from SRIF-IMM sows had greater glucose and free fatty acid concentrations at birth. Key words: Immunization, somatostatin, sow, growth hormone-releasing factor, piglet, growth hormone
ENDOSCOPIC TECHNIQUE TO FOLLOW THE MIXING AND BREAKDOWN OF COLORED FORAGE PARTICLES IN THE RUMINO-RETICULUM OF CATTLE
Authors: LIRETTE A. , MILLIGAN L. P.
Published: March 2010

Three steers prepared with rumen fistulae were used in a completely randomized design to investigate the possibility of using an endoscopic technique to study particulate movement in the rumino-reticulum. Two particle sizes, small particles (1–2 mm, SP) and large particles (10 mm, LP), were introduced into three different locations in the rumino-reticulum at different times. Their movements were inferred from measurements of their presence in seven different areas of the rumino-reticulum by means of a modified endoscope. The breakdown of LP was also calculated. The overall half life (T 1/2) and turnover time for SP were 5.24 ± 0.77 h and 7.56 ± 1.11 h, respectively. Following addition to the rumen both LP and SP mixed throughout the contents. LP disappearance yielded a linear regression equation when values were expressed on a natural log basis. The equations of the kinetic curves of total, intermediate and small fractions were quadratic. In all cases, the equations had an R2 = 0.88 or greater (P < 0.03). The general movement of particulate matter was circular, starting from the anterior and moving posterior via the ventral contents and then moving in reverse through the dorsal area. It was concluded that this endoscopic technique will contribute to the study of rate of passage of digesta and distribution pattern of the rumino-reticulum particulate matter, as well as its breakdown. Key words: Endoscopy, particle movement, rumino-reticulum, cattle
MICROBIAL DEGRADATION OF VITAMIN A IN RUMEN FLUID FROM STEERS FED CONCENTRATE, HAY OR STRAW DIETS
Authors: RODE L. M. , McALLISTER T. A. , CHENG K. -J.
Published: March 2010

The effect of diet on degradation of vitamin A by rumen microorganisms in vitro was investigated. Retinyl acetate was incubated in vitro with rumen fluid from cattle fed high-concentrate (C), hay (H) or straw (S) diets. Residual retinyl acetate and retinol were measured by high-performance liquid chromatography (HPLC), 24 h after retinyl acetate addition to rumen fluid. Retinyl acetate was degraded faster and more extensively in C rumen fluid than in H or S rumen fluid. Retinol levels increased in H and S rumen fluid throughout the incubation period but decreased in C rumen fluid (P < 0.05). Estimated effective ruminal degradation of biologically active vitamin A was 67, 16 and 19% for cattle fed C, H and S diets, respectively. Thirty-three strains of rumen bacteria were surveyed for their ability to degrade retinyl propionate. Of the nine strains that were positive for retinyl propionate degradation, seven were strains associated with starch digestion. The results imply that cattle fed high-concentrate diets will have considerably greater vitamin A requirements than those fed high-forage diets, if oral supplementation of vitamin A is used. Because of the extensive ruminal destruction of vitamin A, intramuscular injection would be a more efficient mode of supplementation for cattle fed high-concentrate diets. Key words: Retinol, retinyl acetate, vitamin A, concentrate, ruminai degradation, cattle, HPLC
RAISED OMEGA-3 FATTY ACID LEVELS IN PIGS FED FLAX
Authors: CUNNANE STEPHEN C. , GANGULI SUJATA , ARMSTRONG JULIA K. , STITT PAUL A.
Published: March 2010

Young growing pigs fed a creep feed containing 5% flax for 8 wk had significantly higher amounts of omega-3 fatty acids in liver, kidney, heart, skin, subcutaneous adipose tissue, and muscle than pigs fed the same diet containing no flax. Increased amounts of desaturation-elongation products of alpha-linolenic acid were observed in liver, heart, kidney and brain. Key words: Flax, alpha-linolenic acid, eicosapentaenoic acid, linoleic acid, arachidonic acid
THE EFFECTS OF MOIST HEAT AND AMMONIA ON THE CHEMICAL COMPOSITION AND FEEDING VALUE OF EXTRUDED CANOLA SCREENINGS FOR MICE
Authors: DARROCH C. S. , BELL J. M. , KEITH M. O.
Published: March 2010

Canola screenings were exposed to moist heat and ammonia during extrusion. The extruded canola screenings (ECS) were then analyzed for chemical components and used in feeding trials to assess their value as a protein and energy supplement. Extruded canola screenings were incorporated into diets at 8.2, 23.4 and 38.6% and fed to weanling male mice for a 2-wk growth period. The interaction of moist heat and ammonia reduced (P < 0.05) the content of glucosinolates and neutral detergent fiber. The addition of ECS to mouse diets increased protein digestibility (P < 0.01) and decreased energy digestibility (P < 0.01). An increase in the extrusion temperature decreased both protein and energy digestibility of the ECS. Increasing the level of ECS in the diet improved mouse weight gains and feed efficiency but decreased intake. Mice fed screenings extruded at higher temperatures had lower weight gains and feed efficiencies. Relatively high fiber and ash levels lowered the feeding value of ECS as a protein supplement when compared to SBM but at low levels of inclusion (≤ 23%), mice fed ECS had comparable weight gains and feed intakes. Key words: Canola screenings, extrusion, moist heat, ammonia, mice
PROTEIN QUALITY OF A NEW HIGH-LYSINE BARLEY DERIVED FROM RISØ 1508
Authors: NEWMAN C. W. , ØVERLAND M. , NEWMAN R. K. , BANG-OLSEN K. , PEDERSEN B.
Published: March 2010

Ca 700202 is a cultivar produced from Risø 1508 in a high-lysine barley breeding program at the Carlsberg Research Center, Copenhagen DK. Two crops of normal (Bomi and Triumph) and high-lysine (Risø 1508 and Ca 700202) barleys were evaluated in two growth and nitrogen balance studies with rats. Barleys were formulated into isonitrogenous, isocaloric diets and fed to 10 weanling male rats in a 21-d growth study and five similar rats in a 9-d nitrogen balance. Average lysine content of Ca 700202 and Risø 1508 (g 16 g−1N) were 47.1 and 40.2% higher, respectively, than the average of the normal barleys. Rats fed Ca 700202 and Risø 1508 consumed more (P < 0.0001) feed than those fed the normal barleys. Final body weights, 21-d gains, feed per unit gain (F:G) and protein efficiency ratio (PER) were superior (P < 0.0001) for rats fed high-lysine compared to the normal barleys. Normal barleys had more digestible protein than high lysine barleys (P < 0.01). Biological value (BV) of Ca 700202 protein was 99.2% compared to 95.9% for Risø 1508 in trial I and 88.2% compared to 85.6% in Trial II which were higher (P < 0.01) than the BV of the protein for normal barley. Net protein utilization (NPU) of rats fed the high-lysine barley was 9% higher (P < 0.01) than the NPU of rats fed the normal barleys. The Ca 700202 barley cultivar yielded 91% of reference barleys but produced a 27% increase in lysine yield per plot. Key words: Protein, amino acids, Hordeum vulgare L., rats, barley
PERFORMANCE OF BEEF STEERS FED GRASS SILAGE WITH OR WITHOUT SUPPLEMENTS OF SOYBEAN MEAL, FISH MEAL AND BARLEY
Authors: VEIRA D. M. , PROULX J. G. , SEOANE J. R.
Published: March 2010

Forty crossbred beef steers were used in a 112-d experiment to study the effect of fish meal (FM, 300 g d−1), soybean meal (SBM, 320 g d−1), barley (B, 2 kg d−1) and B plus FM (2 kg + 300 g d−1) supplementation of grass silage on the performance of growing cattle. The growth rate of steers fed silage was 0.83 kg d−1 and this was increased by 0.15, 0.12, 0.27 and 0.36 kg d−1 by supplements of FM, SBM, B and B + FM. Silage dry matter (DM) intake averaged 2.13% of body weight. Protein supplementation had no effect on silage intake. B and B + FM supplementation increased total DM intake (P < 0.01), but decreased silage consumption by 14% (P < 0.05). Key words: Cattle, grass silage, soybean meal, barley, growth, fish meal
POTENTIAL OF TRITICALE AS A FEED FOR FINISHING HEIFERS
Authors: ZOBELL D. R. , GOONEWAR-DENE L. A. , ENGSTROM D. F.
Published: March 2010

Commercial heifers (n = 120) were randomly assigned to 12 pens (10 heifers/pen) and fed one of four grain diets in combination with barley silage and vitamin premix. Treatments were 100% barley control, 100% triticale, 50% triticale 50% barley, 25% triticale 75% barley. Treatment differences were not significant (P > 0.05) for body weight (BW), average daily gain (ADG), feed intake (FI) and feed:gain (FG).ADG, FI and FG for the 100% triticale treatment were 1.24 kg d−1, 7.88 kg d−1 and 6.29 kg kg−1 respectively, while in the control they were 1.23 kg d−1, 8.03 kg d and 6.39 kg kg−1. Key words: Triticale, heifers, body weight, feed:gain
GC ANALYSES OF CHLORINATED INSECTICIDES IN BOVINE FECES
Authors: NEJAD H. H. , KELLOGG D. W. , DANIELS L. B.
Published: March 2010

Extraction of chlorinated insecticide residues from bovine fecal samples was achieved with 57–88% efficiency, using acetonitrile for extraction, petroleum ether for partitioning and a florisil column for cleanup. Concentrations as low as 0.01 mg L−1 of different chlorinated insecticides in an extract from 20 g of air-dry feces were reliably detected. Key words: Heptachlor, chlordane, bovine feces
EVALUATION OF METHODS TO REDUCE FIGHTING AMONG REGROUPED GILTS
Authors: LUESCHER U. A. , FRIENDSHIP R. M. , McKEOWN D. B.
Published: March 2010

The objectives of this study were to evaluate practical methods to reduce fighting among unacquainted pigs after regrouping. One hundred and forty-four gilts of 95–120 kg body weight were assigned to groups of four previously unacquainted gilts and housed in slatted pens of 9.71 m2 floor area for 4 d. At grouping, the animals were assigned to one of the following six treatments: (1) Control. (2) Gilts were washed and Vicks was applied to their nostrils. (3) A boar of 150 kg body weight was housed with the gilts for 2 d after grouping. (4) 2.2 mg kg−1 of Azaperone (Stresnil) was injected intramuscularly 20 min prior to grouping. (5) The pen was equipped with partitions over the feed trough and one partition in the back. (6) Gilts were not fed that morning and were floor fed at grouping. Gilts were weighed and scored for body lesions at the beginning and end of the trial, and were monitored by video recording for 3 d after grouping. The dependent variables were body weights, lesion scores, and time spent standing and walking, resting, or fighting. Weights and variation in weights did not differ between treatments. Partitions in the pen increased lesion scores for front and cheeks of gilts as compared to control gilts. Boar and Azaperone treatments increased time spent standing and walking, Vicks and partitions reduced these activities. Most fighting took place within the first 2 h after grouping. There was no treatment effect on total amount of fighting, but Azaperone changed the temporal pattern of fighting. Since the amount and intensity of fighting were not influenced by treatment, it is concluded that further research efforts should be directed towards the effect that excitement levels at grouping have on fighting and towards devising methods to minimize the damage resulting from fighting. Key words: Swine, behavior, aggression, fighting, mixing
EFFECT OF HERD-YEAR PRODUCTION LEVEL ON EXPRESSION OF SIRE MERIT
Authors: McEWEN P. L. , WINKELMAN A.
Published: March 2010

Performance data on 110 602 first lactation Holstein cows were utilized to compare the expressions of sire proof at various herd-year production levels. Production traits analyzed were BCA milk, BCA fat and fat percentage. Herd-year averages were partitioned into six groups for each trait. Regression analysis indicated significant interactions between herd-year level and sire estimated transmitting ability (ETA) for daughter milk and fat BCA (P < 0.001). Interaction between herd group and sire proof for fat percentage was found to be insignificant. Linear contrasts were used to compare sire proof slope differences for various herd-year group comparisons. Regression coefficients for sire proof tended to increase as herd-year level increased for both milk and fat yield. The coefficient for sire fat percentage was smaller for the lowest herd-year level when compared to other herd levels. Sire proofs for milk and fat were than categorized into six and seven groups respectively. Sire group and herd-year by sire group interaction were found to account for a significant (P < 0.01) amount of variation in daughter milk and fat yield. Linear contrasts were also used to compare specific sire group differences at various herd production levels. Significant herd-year differences were observed for both daughter milk and fat yield. However specific trends were not prevalent for sire group differences as herd-year groups increased for both traits. Key words: Dairy, sire, daughter
LIVE BODY MEASUREMENTS FROM FIRST-CROSS AND BACKCROSS FEMALES
Authors: McKAY R. M. , RAHNEFELD G. W. , WEISS G. M. , FREDEEN H. T. , NEWMAN J. A. , LAWSON J. E. , BAILEY D. R. C.
Published: March 2010

Live body measurements were evaluated in F1 and backcross females ranging in age from 1 to 5 yr, inclusive, maintained at Manyberries, Alberta (extensive range management) and Brandon, Manitoba (semi-intensive management). The objectives of this study were to examine measures of size, weight, and subcutaneous fat cover to determine: (1) their relationship with age of cow; (2) the impact of varying proportions of Simmental and Charolais breeding; (3) the similarity between generalized and specific contrasts involving 1/4 and 3/4 European continental and British breeding; and (4) differences between four consecutive lactations and three out of four possible lactations. Body length, height at the hips and withers, and cow weight at weaning reached or approached their mature levels by 5 yr of age and subcutaneous fat cover was more dependent upon environmental factors than age. Incremental increases in Simmental and Charolais breeding in the cow crosses resulted in corresponding increases in body size and weight. The generalized comparisons between 1/4 and 3/4 Simmental, Charolais, Angus, Hereford, and Shorthorn breeding provided useful information regarding generic comparisons but there was a need for evaluating specific backcross comparisons. Cows experiencing four consecutive lactations, compared to those that had three lactations out of a possible four, had decreased physical dimensions in addition to weight and subcutaneous fat cover. Key words: Beef cattle, body measurements, backcrosses, heifers, cows
EFFECTS OF POSTMORTEM GLYCOLYSIS ON THE QUALITY OF HOT-DEBONED BOVINE MUSCLE
Authors: BRUCE H. L. , BALL R. O.
Published: March 2010

Meat tenderness may be improved by accelerating muscle metabolism or by damaging muscle structure and increasing the solubility of muscle proteins. Pre- and postrigor protein and collagen solubilities were measured in semitendinosus muscles, removed pre-rigor from 24 Charolais crossbred steer carcasses, that were either unstimulated or electrically stimulated (115 V, 0.25 amp, 60 Hz) within 1 h postexsanguination to accelerate muscle metabolism. Temperature, pH, Hunterlab color reflectance, sarcomere length and lactate concentration were measured during ageing. Shear force was measured on aged (7 d) muscle only. Low voltage electrical stimulation increased glycolytic rate as indicated by significantly (P < 0.05) lower pH and higher L-lactate concentrations of stimulated muscles as compared to control muscles. Total and sarcoplasmic protein solubilities decreased due to ageing, and myofibrillar protein solubility increased; however, collagen solubilities were unchanged. Low voltage electrical stimulation did not affect color reflectance, sarcomere length or shear force, indicating that an increased rate of glycolysis alone was not sufficient to effect increases in meat tenderness. Key words: Beef, electrical stimulation, meat quality, muscle
GLUCOSE AND ALANINE METABOLISM IN CHRONICALLY COLD-EXPOSED SHEEP
Authors: EARLY RICHARD J. , THOMPSON JAMES R. , CHRISTOPHERSON ROBERT J.
Published: March 2010

Glucose and alanine metabolic interrelationships (measured with 3H-glucose and 14C-alanine) were examined in closely shorn wethers subjected to thermoneutral (TN) temperatures or chronic cold exposure (CE, < 21 d). Three treatments (n = 5–6 per treatment) were used: (1) fed to maintain weight at 18–20 °C (TN-Low); (2) fed to maintain weight at 0–4 °C (1.5 × TN-Low intake, CE-Hi); and (3) fed at CE-Hi intake at 18–20 °C (TN-Hi) to distinguish effects of the higher feed intake in the CE-Hi sheep from the cold per se. Plasma glucose pool size increased (P < 0.1) in CE-Hi sheep from 1.81 (TN-Low) and 1.83 (TN-Hi) to 2.40 mmol kg−0.75. Plasma glucose entry rates increased (P < 0.001) from 0.91 (TN-Low) to 1.29 (TN-Hi) to 1.78 (CE-Hi) mmol h−1 kg−0.75. Plasma alanine entry rates showed a tendency (P = 0.19) to increase in the CE-Hi sheep. Percentage alanine converted to glucose increased (P < 0.1) from 14.2% (TN-Low) and 13.4% (TN-Hi) to 21.5% (CE-Hi). These results indicate that increased glucose metabolism in cold-exposed sheep is a chronic adaptation. The data also suggest that the rate of alanine conversion to glucose increases during chronic cold exposure. Key words: Alanine, glucose, chronic cold exposure, sheep
COMPARISON OF FORAGE DIGESTION BY CATTLE AND HORSES
Authors: CYMBALUK N. F.
Published: March 2010

Two trials compared digestion of Saskatchewan-grown hays by cattle and horses. In the first study, Altai wildrye (Leysum angustus Trin.), smooth bromegrass (Bromus inermus Leyss.), crested wheatgrass (Agropyron cristatum L.), Kentucky bluegrass (Poa pratensis L.), oat hay (Avena sativa L.) and reed canarygrass (Phalaris arundinaceae L.) hays were fed to six beef steers and six crossbred geldings. The second study compared alfalfa hay (Medicago sativa L.) to dehydrated alfalfa pellets. Voluntary dry matter intake (VDMI) of hay by cattle was related to neutral detergent fiber content (R2 = 0.66). No single nutrient reliably predicted VDMI by horses. Cattle and horses had the highest VDMI for bromegrass hay in trial 1. Cattle had similar intakes of dehydrated alfalfa pellets and alfalfa hay, but horses ate 17% more (P < 0.05) hay than pellets. Cattle digested 28–82% more (P < 0.05) fiber from grass hays than horses which may account for their higher dry matter (DM) digestion of these hays. Cattle and horses utilized legume feeds similarly. Energy intakes of all animals exceeded maintenance except for cattle fed reed canarygrass hay. True crude protein digestibility and metabolic fecal protein of forage-fed cattle and horses were estimated at 83.4 and 80.3%, and 2.67 and 2.17 g 100 g−1 DM intake, respectively. Horses had higher true digestibilities of Ca (75%) than P (33%) but cattle digested more P (76%) than Ca (32%). Endogenous fecal Ca excretion for cattle and horses were assessed at 6.5 and 22.1 mg kg−1 body weight (BW), respectively, while endogenous fecal P excretions were 13.3 and 10.2 mg kg−1 BW, respectively. Key words: Horse, cattle, legume, grass, crude protein, fiber
ARTIFICIAL REARING OF COLOSTRUM-DEPRIVED PIGLETS USING IRON CHELATORS: IN VITRO AND IN VIVO COMPARISONS OF EDDHA AND HBED WITH AND WITHOUT PORCINE IMMUNOGLOBULINS
Authors: DREW M. D. , BEVANDICK I. M. , OWEN B. D.
Published: March 2010

Two iron chelators, ethylene diamine-di-orthohydroxyphenyl acetic acid (EDDHA) and N,N′-Bis(o-hydroxybenzyl)-ethylenediamine diacetic acid (HBED), were investigated as possible substitutes for lactoferrin in sow milk replacers. The antibacterial properties of lactoferrin, EDDHA and HBED, with and without porcine immunoglobulins, were compared in vitro using E. coli 0 157 K88. Lactoferrin and EDDHA inhibited the growth of E. coli over a 12-h incubation period, while HBED had no effect on bacterial growth. Porcine immunoglobulins inhibited the growth of E. coli after 6, but not after 12 h of incubation. Ethylene diamine-di-orthohydroxyphenyl acetic acid and HBED were further compared as substitutes for lactoferrin in sow milk replacers fed to colostrum-deprived piglets. All piglets received porcine immunoglobulins for 24 h following birth. They then received EDDHA, HBED or no chelator with or without porcine immunoglobulins on days 2–14. Piglets that received HBED had lower survival rates and weight gains than piglets that received EDDHA or no chelator. Weight gains were equal for piglets receiving either EDDHA or immunoglobulins alone and there was no additive effect on piglet weight gains when EDDHA and immunoglobulins were fed together. Ethylene diamine-di-orthohydroxyphenyl acetic acid may be a practical substitute for lactoferrin in sow milk replacers. Key words: Immunoglobulins, piglet, lactoferrin, iron chelators, E. coli
INTERACTION OF CALCIUM AND SULPHUR IN CANOLA AND SOYBEAN MEAL DIETS FED TO BROILER CHICKS
Authors: SUMMERS J. D. , BEDFORD M. , SPRATT D.
Published: March 2010

Several studies were undertaken to investigate the interaction of calcium and sulphur when added to semi-purified diets containing either canola or soybean meal, as the only protein source. High levels of sulphur supplementation reduced the performance of birds fed diets containing both sources of protein; however, it was more severe with canola than with soybean meal diets. Sulphur coming from methionine resulted in poorer bird performance than that coming from cystine. Increasing dietary calcium levels from low to close to the requirement level partially alleviated the detrimental effects of the higher sulphur supplementation. Liver weight was not altered, as a percent of body weight, at the high sulphur levels, suggesting little or no liver involvement in the reduced performance noted. Reduced performance often reported for birds fed canola versus soybean meal diets may well be due, in part, to the higher level of sulphur in canola meal than soybean meal, in particular the inorganic sulphur fraction. However, the present study utilized diets containing 40% canola meal, which is much higher than would be found in practical type diets. Thus care must be taken in extrapolating the present findings to practical conditions. Key words: Chickens, canola, calcium, sulphur, methionine
DAY-TO-DAY VARIATIONS IN FAT PERCENT OF COW'S MILK
Authors: ATWAL A. S. , ERFLE J. D.
Published: March 2010

Large day-to-day variations in milk fat, particularly for the morning milkings, were observed in 36 Holstein cows. Changes in percent fat were gradual and produced wavelike patterns in a number of instances. Supplemental feeding of long hay had no effect on acetate/propionate ratio in rumen fluid, daily milk yield or weighted milk fat percentage. Key words: Dairy cows, milk, fat depression, hay
INCIDENCE OF CHROMOSOMAL ANOMALIES AMONG WESTERN CANADIAN BEEF CATTLE
Authors: SCHMUTZ SHEILA M. , FLOOD PETER , MOKER JANE , BARTH ALBERT , MAPLETOFT REUBEN , CATES WILLIAM
Published: March 2010

One hundred and thirty-four bulls representing 11 different beef breeds were karyotyped. Abnormal karyotypes were found in eight animals. Five bulls carried one copy of the 1;29 translocation, two bulls carried two copies, and one bull was a 60,XX/60,XY chimera. No association between scrotal circumference and risk of carrying the translocation was found. All bulls carrying the translocation were of continental beef breeds. No translocations were found in the 38 bulls of the British breeds: Hereford, Angus, and Shorthorn. Key words: Translocation, chimera, chromosome, fertility, beef cattle