bluuebunny/crossref_metadata_2025 huggingface dataset:
UTILIZATION OF SUGAR CANE FINAL MOLASSES BY THE PIG: ENERGY METABOLISM
Authors: BAYLEY H. S. , FIGUEROA VILDA , LY J. , MAYLIN A. , PEREZ A.
Published: March 2010

A sample of sugar cane final molasses (82.5% dry matter) contained the following components (percent of dry matter): ash, 11.4; sucrose, 32.8; fructose, 21.1; glucose, 7.4; and unidentified organic matter, 27.3. Three diets were prepared by mixing soybean meal with either starch, molasses, or a mixture of sugars to simulate those in the molasses. The digestible and metabolizable energy values of the diets were measured with pigs of approximately 35 kg liveweight. The digestible and metabolizable energy values of the molasses were 12.3 and 11.8 MJ/kg dry matter, respectively. The metabolizable energy values of the sugar mixture and the unidentified organic matter were 16.5 and 6.1 MJ/kg, respectively. The heat production of pigs of approximately 13 kg liveweight was measured following the consumption of the three diets, and their energy retention was calculated. The metabolizable energy from the molasses was retained at least as well as that from the other two diets, showing that the mixture of glucose and fructose absorbed from the molasses was an efficient metabolic fuel. These observations suggest that the reduction in performance which usually follows the substitution of molasses for cereals in pig diets is due to the low metabolizable energy value of the molasses coupled with failure of the pigs to increase feed consumption to maintain metabolizable energy intake. Key words: Molasses, pigs, digestible energy, metabolizable energy, respiration calorimetry
EFFECT OF THE THERMAL ENVIRONMENT ON DIGESTION IN RUMINANTS
Authors: CHRISTOPHERSON R. J. , KENNEDY P. M.
Published: March 2010

Literature relating to the influence of temperature on digestibility in ruminants has been reviewed. Decreases in digestibility of certain diets induced by exposing animals to low environmental temperatures are related to changes in the rate of passage of digesta through the gastrointestinal tract. The increased rates of passage are due to enhanced gastrointestinal motility and likely, for some diets, to enhanced rumination activity. Opposite changes in these digestive parameters appear to occur in response to heat stress. The digestibility of 100% concentrate diets appears not to be temperature dependent. Digestion of ground and pelleted forage diets is more consistently affected by temperature than chopped forages and the response appears to differ between forage plant species. The effects on digestion influence the availability of dietary energy to a greater extent than protein. For some diets cold exposure results in increased urea nitrogen recycling to the rumen, increased efficiency of rumen microbial synthesis and reduced rumen degradation of dietary protein; responses which help to favor the nitrogen economy of the animal even though digestible energy is reduced. The increased rate of passage of digesta residues in the cold may help to support increases in the voluntary intake of diets offered ad libitum. Key words: Digestion, ruminants, temperature, environment
GENERAL, SPECIFIC, MATERNAL AND RECIPROCAL EFFECTS FOR EWE PRODUCTIVITY IN CROSSING FIVE BREEDS OF SHEEP
Authors: SHRESTHA J. N. B. , REMPEL W. E. , BOYLAN W. J. , MILLER K. P.
Published: March 2010

Five breeds of sheep (Minnesota 100, 102, 103 and 105, and Shropshire), and their two breed crosses, including reciprocals, were raised at the University of Minnesota's Agricultural Experiment Stations, Rosemount and Waseca. Included in this study were 421 purebred and 1037 crossbred ewes and their 367 purebred and 849 Suffolk-sired crossbred lambs born over a 5-yr period. Estimates of heterosis, pure breed, general, specific, maternal and reciprocal effects were obtained for fertility, prolificacy, livability, overall reproduction, and total and average lamb weights per ewe at birth and weaning (100 days). Significant differences were observed for prolificacy, livability, and total and average lamb weights per ewe at birth and weaning. General combining ability was important (P < 0.01) for prolificacy and average lamb weight per ewe at birth and weaning. Specific combining ability was significant for prolificacy, total lamb weight per ewe at birth, and average lamb weight per ewe at weaning. Maternal and reciprocal effects were not important (P > 0.05). Significant interactions of location with specific combining ability and maternal ability were observed for average lamb weight per ewe at weaning. Breeds ranked differently on purebred performance and general combining ability. Heterosis, pure breeds, and general and specific combining ability had important effects. Therefore, both additive and non-additive effects should be considered in developing breeding strategies to maximize productivity for commercial lamb production. Key words: Sheep, breed, ewe productivity, genetic effects
REGIONAL CHARACTERISTICS OF HOG CARCASSES IN CANADA: A SURVEY CONDUCTED IN THE SPRING OF 1981
Authors: FORTIN A. , HOSKINS V. E. , SIM D. W.
Published: March 2010

During the spring of 1981, 12 064 hog carcasses were randomly selected from the commercial kill of major abattoirs located within each of the major hog producing regions of Canada, namely the Maritimes, Quebec, Ontario, Manitoba, Saskatchewan and Alberta. Under abattoir conditions, warm carcass weight, maximum backfat thickness at the shoulder and at the loin, minimum backfat thickness over them. gluteus medius and the sum of maximum backfat thickness at the shoulder and loin were recorded for each carcass. Regional differences in the relative frequencies of carcasses in the weight and fat classes were observed. In the eastern provinces (Maritimes, Quebec and Ontario) slightly more than 25% of the sampled carcasses weighed between 81.5 ann 90.5 kg, whereas in the prairie provinces (Manitoba, Saskatchewan and Alberta) this percentage was reduced to 17.3—19.5%. Carcasses less than 72.5 kg represented a higher percentage (28.2–31.4%) in the latter region compared to a range of 16.3–18.3% in the eastern provinces. The data indicated that Manitoba produced proportionally the least of the 'fat carcasses' (fat classes 8–16) and the most of the 'average carcasses' (fat classes 5–7) followed by the Maritimes, Ontario, Quebec, Saskatchewan and Alberta. Despite finding proportionally more carcasses weighing less than 72.5 kg in Alberta and Saskatchewan, the relative frequency of 'fat carcasses' was higher than in any other province or region. The average index as determined under both the 1979 and 1982 grading regulations varied from region to region, with the lowest in Alberta and the highest in Manitoba. However, the effect of the latest revision of the grading regulations on regional average indices was minimal. Key words: Hog, carcass characteristics, 1981, Canada, region, grading
METABOLIC RESPONSES OF EWES TO DIFFERENT PROTEIN INTAKES DURING LATE GESTATION
Authors: LYNCH G. P. , JACKSON Jr. C.
Published: March 2010

An indicator of a ewe's protein status would be of value for nutritional management. Thirty crossbred ewes in midgestation were assigned equally to three treatments of 12 (HP), 9 (MP) and 7% (LP) crude protein, isocaloric diets and fed ad libitum. Weekly determinations of a serum metabolic profile, 3-hydroxybutyrate, copper, iron, total (TIBC) and unbound (UIBC) iron-binding capacity and urine ketones, bilirubin and urobilinogen were made for each ewe. The experiment was terminated for each ewe at parturition and data were assigned to a week of gestation. Feed intake and body weight were highest for ewes on the MP treatment. The LP ewes consumed from 102 down to 39% of their National Research Council (NRC) requirement for protein from beginning to the end of the experiment. Lower UIBC and decreased serum copper levels were shown by the LP-treated ewes. Both urine bilirubin and urobilinogen were increased by the LP-treated ewes, evidence of impaired liver function. A progressive decrease in BUN and serum albumin was shown by the LP treatment. The serum enzymes glutamic oxaloacetic transaminase and γ-glutamyl transpeptidase were increased by LP treatment. These increases are evidence of impaired liver function. The onset of impaired liver function and a reduction in serum albumin may be useful for detecting a response to poor protein status of the gestating ewe. Key words: Gestating ewes, protein status, metabolite responses, impaired liver function
EFFECTS OF MASH DIET AND PELLETS UPON DIGESTIVE MOTOR FUNCTIONS IN DOMESTIC HENS AND GUINEA HENS
Authors: ROCHE M. , ACHARD F. , RUCKEBUSCH Y.
Published: March 2010

The changes of gastric and intestinal motilities induced by food restriction and refeeding with pellets instead of an all-mash diet were compared in hens and guinea hens. Smooth muscle electrical activity was recorded in both species, which differed by their degree of domestication and food habits. Six-day fasting reduced gastric activity in both species, a phenomenon paralleled by an increase in intestinal motility and the disappearance of the diurnal cycles of gastro-intestinal activity. Refeeding increased gastric activity and reduced the intestinal activity in hens. By contrast with hens, pellets failed to induce major changes in the guinea hens, despite an increased frequency of gastric spike bursts and inhibition of the orad propagation of the intestinal spike bursts. The results suggest that hens, despite a lower responsiveness to environmental changes, are more sensitive than guinea hens to changes in diet. Key words: Birds, digestive electromyography, diet, physiological rhythms
SUPPLEMENTAL VALUE OF ASCORBIC ACID DURING LATE GESTATION ON PIGLET SURVIVAL AND EARLY GROWTH
Authors: CHAVEZ E. R.
Published: March 2010

Twenty-six pregnant sows were included in four different dietary treatments as follows: (1) Control group with no vitamin C supplementation; (2) vitamin-C-supplemented group receiving 1 g/day ascorbic acid provided in a gelatin capsule; or (3) vitamin-C-supplemented group receiving 1 g/day ascorbic acid in a powder form spread on the top of the pelleted meal; (4) as (3) but receiving 10 g/day ascorbic acid. Vitamin-C-supplemented sows in treatments 2 and 4 showed a significant (P < 0.05) increase in blood plasma vitamin C prefarrowing. Pregnant sows receiving 10 g/day vitamin C supplement showed a significantly (P < 0.05) higher concentration of this vitamin in the urine than either control or sows receiving 1 g/day vitamin C supplementation. Sows in treatment 4 showed a significantly higher (P < 0.05) vitamin C content in colostrum than control animals. During lactation, no significant difference in vitamin C content in milk was observed between control and animals receiving 10 g/day vitamin C supplement. The vitamin C content in the plasma of the piglets at birth indicated that supplementing vitamin C to the mothers, significantly (P < 0.05) increased the concentration of this vitamin in the newborn piglet compared to control animals. However, the piglet survival and growth up to weaning at 3 wk of age was not significantly affected by dietary vitamin C supplementation of the mothers' diet. Key words: Ascorbic acid, gestation, piglet survival, Vitamin C
A SURVEY OF THE THIAMIN STATUS OF GROWING AND FATTENING CATTLE IN ALBERTA FEEDLOTS
Authors: GRIGAT G. A. , MATHISON G. W.
Published: March 2010

A survey of 239 steers at three locations in Alberta was conducted to study the occurrence of thiamin deficiencies in growing and fattening cattle. The percentage increase in the activity of the erythrocyte transketolase enzyme (E.C.2.2.1.1) following preincubation with thiamin pyrophosphate (TPP effect) was used as the index of thiamin status. We found that only 1.7% of the samples taken had a TPP effect in excess of 15% indicating that a low proportion of the animals sampled were deficient in thiamin. A trend (r = − 0.824; [Formula: see text]) for a negative relationship existed between mean TPP effects and mean dietary crude protein concentrations. Weaning stress did not result in TPP effects over 15%. Key words: Thiamin, feedlot steers, erythrocyte transketolase, TPP effect
INFLUENCE OF FEEDING FREQUENCY ON PASSAGE OF FLUID AND PARTICULATE MARKERS IN STEERS FED A CONCENTRATE DIET
Authors: GOETSCH A. L. , GALYEAN M. L.
Published: March 2010

Four beef steers were used to study the influence of feeding a 75% concentrate diet twice (2 ×) versus eight times (8 ×) daily on fluid and particulate passage rate estimates. Passage of ruthenium phenanthroline was not altered by feeding frequency; however, particulate dilution rates differed (P < 0.05) when determined by rumen sampling compared with fecal sampling in 2 ×, but not in 8 × steers. Passage of cobalt ethylenediamine tetracetic acid determined from fecal sampling was higher (P < 0.05) in 8 × than in 2 × steers, but ruminal estimates did not differ. Molar proportions of acetate and butyrate were higher (P < 0.05) and propionate lower (P < 0.05) in 8 × than in 2 × steers. Key words: Feeding frequency, particulate and fluid passage, rumen fermentation
THE INFLUENCE OF PERFORMANCE TEST DURATION AND SELECTION INTENSITY IN SWINE EVALUATION PROGRAMS
Authors: SATHER A. P.
Published: March 2010

The problem of optimizing the use of limited test station facilities was considered in terms of varying performance test duration and intensity of selection using part-record genetic parameters for feed conversion ratio (FCR) and average daily gain (ADG). Average backfat (ABF) was limited to the market weight period. Full test duration, based on 396 Lacombe barrows and gilts was 88.5 days with FCR of 2.96, ADG of 0.84 kg/day, and ABF of 19.4 mm at a market weight of 93 kg. Proportions saved (p) of tested animals based on the whole record were 0.10, 0.25 and 0.50. As test station capacity was increased by reducing test duration, p was decreased such that a constant number of animals would be retained within each level of selection intensity. Optimum test period for FCR, ADG and index selection all coincided with the same test period. However, as p increased from 0.10 to 0.50, the optimum on test weight increased from 52 kg to 65 kg with a similar corresponding increase in on-test age from 98 days to 112 days. The test terminated at market weight. Gains in efficiency were 12%, 23% and 50% for index selection when the test period began at 52 kg, for p of 0.10, 0.25 and 0.50, respectively. Since very efficient animals would be near market weight by the on-test age of 98 days, test periods defined in terms of constant weight, rather than constant age, were deemed most suitable. Other limitations to the model and use of part-record selection procedures were discussed. Key words: Swine, part records, performance evaluation, station testing
THE EFFECTS OF ZERANOL ON THE FEEDLOT PERFORMANCE OF BEEF BULLS
Authors: PRICE M. A. , MAKARECHIAN M. , TENNESSEN T. , MATHISON G. W.
Published: March 2010

Fifty-three cross-bred bulls, aged 5–7 mo, were divided at random into a nonimplanted control group of 26 bulls and a treatment group of 27 bulls, which were each implanted with 36 mg of zeranol on the 1st, 81st, and 155th day of the experiment. They were fed a high energy diet ad libitum for 168 days during which time liveweight and feed consumption were recorded at 2-wk intervals. Occasional measurements of scrotal circumference and serum T3 and T4 concentration were taken on 26 bulls (12 control, 14 implanted). At the end of 168 days the same 26 bulls were halter-broken in preparation for libido testing and semen evaluation. All bulls were slaughtered 236 days after the initial implanting, at which time a study was made of the behavior of 20 control and 20 treated bulls during the 6–7 h leading up to slaughter. There was a large (6.1%) but nonsignificant difference in rate of gain, with no difference in feed efficiency due to the implant. Zeranol was found to have no significant effect on sexual development, thyroid hormone concentration, behavior or carcass characteristics. There was, however, a four-times greater incidence (nonsignificant) of dark-cutting carcasses among the control bulls, than the treated bulls. Key words: Zeranol, beef cattle, feedlot performance, sexual development, behavior
CIRCANNUAL CHANGES IN SERUM LEVELS OF PITUITARY HORMONES AND TESTOSTERONE AND IN TESTIS SIZE OF SEXUALLY ACTIVE AND INACTIVE ADULT RAMS
Authors: SANFORD LEE M. , YARNEY THADDEUS A.
Published: March 2010

The influence of the social environment of adult rams on testicular function and the secretion of pituitary hormones was investigated between May 1978 and October 1979. Twelve rams, 3–6 yr of age, were penned in three groups of four, either as a sexually inactive all-male group or as sexually active groups adjacent to or together with ovariectomized ewes that were hormonally induced into estrus every 10 days. At approximately monthly intervals measurements of testis size were recorded and rams were bled by venepuncture from the jugular vein at 20-min intervals for 8 h (0900–1700 h). Sera were assayed for luteinizing hormone (LH), follicle stimulating hormone (FSH), prolactin (PRL) and testosterone. Since seasonal changes in testicular and endocrine characteristics for the sexually active groups were similar, data for these groups were combined. Differences in the circannual testicular rhythm were not observed between ram groups until the onset of the second breeding season; at this time (August 1979), sexually active rams had significantly (P < 0.05) higher scrotal circumference measurements (36.0 ± 0.9 vs. 32.2 ± 1.0 cm) and circulating testosterone levels (10.7 ± 1.6 vs. 6.7 ± 1.5 ng/mL), and significantly (P < 0.05) lower LH levels (0.75 ± 0.10 vs. 2.04 ± 0.40 ng/mL) than sexually inactive rams. The increase in rate of testicular redevelopment for sexually active rams during late summer was not preceded by significantly (P > 0.05) higher seasonal elevations in circulating LH and FSH levels, although PRL levels in May through July were only 50% of those observed for the sexually inactive rams. Sexually active rams also exhibited significant (P < 0.01) increases in LH and testosterone secretion in the nonbreeding season when ewes were sexually receptive. Ejaculation frequency during a 4-h test period at the conclusion of the study was similar for both groups of rams. Data indicate that long-term exposure of adult rams to estrual ewes results in an increase in rate of testicular redevelopment during the summer in preparation for the fall breeding season. Key words: Circannual changes, pituitary hormones, testosterone, testis, mating, ram
NURSING AND CROSS-NURSING BEHAVIOR OF BEEF CATTLE IN CONFINEMENT
Authors: LEWANDROWSKI N. M. , HURNIK J. F.
Published: March 2010

Observations of 42 cow-calf pairs were collected over a 100-day postpartum interval to study the nursing and suckling behavior of beef cattle. Most calves (93%) displayed cross-suckling at some time during the study, but cows were slightly more selective (83%) in tolerating cross-suckling. Number of nursing events per day averaged 4.9 and time per event averaged 10.4 min. Number of cross-nursing events averaged 0.3 events per day and time per event averaged 5.0 min. About 61% of nursing took place from 0600–1800 h and 39% from 1800–0600 h. The lowest incidence of nursing in the morning occurred between 0400–0500 h and in the evening, between 2200–2300 h. Cross-nursing followed a similar distribution with 74% occurring between 0600 and 1800 h and 26% between 1800 and 0600 h. The number of suckling events and time spent suckling per day remained relatively constant over the 100-day postpartum period. Conversely, cross-suckling gradually increased. The number of nursing and cross-nursing events per day and time spent nursing per day were unaffected by estrous behavior. Key words: Beef cattle, nursing, cross-nursing, suckling, cross-suckling
PERFORMANCE OF HEREFORD × SHORTHORN BULLS AND STEERS RAISED IN NORTHERN ONTARIO AND FED DIFFERENT LEVELS OF GRASS SILAGE AND HIGH MOISTURE BARLEY
Authors: VEIRA D. M. , FORTIN A. , IVAN M. , BUTLER G. , PROULX J. G.
Published: March 2010

Over a 2-yr period, 44 bulls and 44 implanted steers of Hereford × Shorthorn breeding were fed, from weaning to slaughter, diets of grass silage with 0, 0.45, 0.9 or 1.35 kg barley dry matter (DM)/100 kg liveweight. Each animal was slaughtered when it had 8 mm of fat over the loin as determined by ultrasound measurement. As the level of barley in the diet increased the rate of gain increased (P < 0.01), as did DM intake (P < 0.05) while feed required per kilogram gained and days on feed decreased. Bulls and steers responded in a similar manner to the different diets. Bulls gained faster (P < 0.01) on similar intakes of DM with the result that feed required for kilogram gain was less for bulls (P < 0.05). There was no difference (P > 0.05) in days to market for bulls and steers. There was no consistent effect of diet on carcass characteristics. However, castration resulted in lighter (P < 0.01) slaughter and carcass weights as well as a smaller (P < 0.01) rib eye area. Key words: Cattle, castration, diet, growth, carcass
EFFECTS OF FEEDING AVOPARCIN IN COMBINATION WITH PROGESTERONE-ESTRADIOL IMPLANTS ON GROWING AND FINISHING STEERS
Authors: MURRAY D. A. , BURGESS T. D. , MOWAT D. N.
Published: March 2010

Two, experiments were conducted with growing and finishing steers to determine the performance response to feeding avoparcin with or without progesterone-estradiol (Synovex-S) implants. In exp. 1, 96 crossbred yearling steers were fed diets containing 40% hay crop silage (DM basis) for 168 days. Avoparcin increased (P < 0.05) weight gains (16%) and feed efficiency (16%). Initial Synovex-S implants increased (P < 0.05) weight gain (14%) and feed efficiency (11%). Reimplanting at 112 days tended to further improve (P > 0.05) rate of gain and feed efficiency over initial implanting. In exp. 2, 80 Hereford yearling steers were fed diets containing only 19% corn silage (DM basis) for 98 days. Avoparcin had no effect on weight gain but improved (P > 0.05) feed efficiency (11%). Synovex improved (P < 0.05) weight gain (17%) and feed efficiency (11%). In both experiments treatments produced no effects on carcass measurements except for an increase in warm carcass weight. Also, in both experiments the effects of avoparcin and Synovex on feed efficiency were fully additive. Key words: Growth promotants, implants, feed additives, steers
RESPONSE OF DAIRY COWS TO FORMALDEHYDE-TREATED CANOLA MEAL DURING EARLY LACTATION
Authors: RAE R. C. , INGALLS J. R. , McKIRDY J. A.
Published: March 2010

Forty Holstein cows were assigned to one of four isocaloric diets 2 wk postpartum in a 2 × 2 factorial arrangement. Factor I was dietary crude protein (CP) level, either 17.4% or 14.6% CP. Factor II was formaldehyde (FA) treatment of canola meal, either treated or untreated. The experimental period lasted 12 wk. Treatment with FA had no effect on milk yield, milk composition, dry matter (DM) intake or on apparent digestibilities of DM, nitrogen (N) or acid detergent fiber (ADF). FA treatment reduced ammonia-N (NH3-N) levels in rumen liquor (P < 0.05), tended to increase (P < 0.1) plasma levels of total essential amino acids and had no effect on plasma urea. High dietary CP increased (P < 0.05) milk and lactose yields, had no effect on rumen liquor NH3-N levels and increased (P < 0.05) plasma levels or urea and total essential amino acids. Treatment with FA appears to have increased absorption of total essential amino acids from the gut but did not increase milk production. Possibly, amino acid supply to the mammary gland did not limit milk synthesis in this experiment. Alternatively, FA treatment may have failed to increase absorption of the amino acids whose availability did limit milk synthesis. FA treatment apparently destroyed 58% of canola meal tyrosine and 29% of the lysine and this may be partially responsible for the lack of a response in milk production. Key words: Holstein, formaldehyde, canola meal, milk production, protein level, amino acids
THE INVESTIGATION OF SODIUM BICARBONATE OR BENTONITE AS SUPPLEMENTS IN SILAGES FED TO LACTATING COWS
Authors: FISHER L. J. , MACKAY V. G.
Published: March 2010

Two experiments with lactating Holsteins were carried out to determine the effectiveness of sodium bicarbonate (NaHCO3) or bentonite, added to silage prior to feeding, as a means of increasing dry matter intake. In the first trials the feed, consisting of 10% grain mixture, 45% grass silage and 45% corn silage, was supplemented with 0, 0.6 or 1.2% bentonite in a 3 × 3 latin square utilizing 12 cows and 28-day test periods. Neither level of bentonite improved dry matter intake or milk yield. Milk composition, molar proportions of rumen volatile fatty acids, plasma calcium and phosphorus were not influenced by additions of bentonite. Apparent dry matter digestibility was significantly reduced (P < 0.05) by the addition of bentonite at the 0.6 and 1.2% levels compared to the cows fed the unsupplemented ration. The digestibility of acid detergent fiber was lower (P < 0.05) for cows fed the silage mixture supplemented with 1.2% bentonite than for the controls. In the second trial a silage mixture consisting of approximately 30% grass silage and 70% corn silage was supplemented with either 0.8% NaHCO3, 2.1% bentonite or neither and fed in a 3 × 3 latin square utilizing 15 cows and 28-day treatment periods. Compared to control cows, neither NaHCO3 nor bentonite had any significant (P > 0.05) influence on dry matter intake, milk yield or rumen fermentation. However, the addition of NaHCO3 to the silage improved milk yield and feed conversion (P < 0.05) when compared to cows fed the silage supplemented with bentonite. It was concluded from these trials that bentonite should not be used as a supplement to silage diets fed to lactating cows. The results suggested that NaHCO3 supplementation had little if any beneficial effect when grass silage made up approximately 30% of the total diet. Key words: NaHCO3, bentonite, lactating cows, silage intake, digestibility
THE METABOLISM OF THE MYCOTOXIN ZEARALENONE AND ITS EFFECTS ON THE REPRODUCTIVE TRACTS OF YOUNG MALE AND FEMALE PIGS
Authors: FARNWORTH E. R. , TRENHOLM H. L.
Published: March 2010

Young male and female pigs were dosed orally with either 0, 5, 10 or 15 mg/kg BW of purified zearalenone. Blood samples taken for the next 7 h contained both conjugated zearalenone (139–317 ng/mL) and α-zearalenol (65–319 ng/mL). In most cases the zearalenone concentration exceeded that of α-zearalenol. Urine samples collected from male pigs contained high levels of conjugated zearalenone (42–197 μg/mL) and α-zearalenol (5–80 μg/mL). One week later, reproductive tracts of females that had received the zearalenone were greatly enlarged compared with controls. Male reproductive tracts tended to be smaller in animals receiving the toxin compared with controls. Key words: Pigs, zearalenone, mycotoxin, metabolism
STUDIES ON THE PERFORMANCE, DEVELOPMENT AND CARCASS COMPOSITION OF THE GROWING PIG: EFFECTS OF SEX, FEEDING REGIME AND AGE ON BLOOD SERUM PARAMETERS
Authors: DOORNENBAL H. , TONG A. K. W. , MARTIN A. H. , SATHER A. P.
Published: March 2010

Blood samples from 120 pigs serially slaughtered at five age groups, starting at 85 days of age with intervals of 2 wk, were used to study the effects of sex, feeding regime and age on a 12 component metabolic blood serum profile. The differences between barrows and gilts were small and only significant (P < 0.05) for blood urea. Pigs fed ad libitum had a significantly (P < 0.05) higher level of blood urea, calcium, inorganic phosphorus and alkaline phosphatase but a significantly (P < 0.01) lower level of creatinine than restricted fed pigs. Age had the most pronounced effects on the serum parameters studied, with blood urea, calcium, bilirubin, creatinine, total serum protein and albumin showing a significant (P < 0.01) increase per unit of serum with increasing age. The serum glucose, inorganic phosphorus, glutamic oxaloacetic transaminase and lactate dehydrogenase were also significantly (P < 0.01, P < 0.05 for glucose) influenced by age but did not show a consistent trend across the age groups. Serum alkaline phosphatase was the only component which significantly (P < 0.01) decreased with age. The results indicate that when these serum components are to be used for diagnostic or comparison purposes, age adjustment must be applied. Key words: Blood parameters, pigs, age, feeding regime, sex
BREED OF DAM, AGE OF DAM AND SEX OF CALF EFFECTS IN THE CANADIAN SIMMENTAL YOUNG SIRE PROVING PROGRAM
Authors: KEMP R. A. , SCHAEFFER L. R. , WILTON J. W.
Published: March 2010

Canadian Simmental Association Young Sire Proving Program records (1978–1982) were used to estimate breed of dam by age of dam by sex of calf effects for several traits. Two models were used. Model 1 included fixed herd-years, breed of dam by age of dam by sex of calf (BAX) plus random sire and residual effects. Model 2 included fixed herd-year by sex of calf and breed of dam by age of dam (BA) plus random sire and residual effects. Both models included additive genetic relationships among sires and maternal grandsires. Traits used with Model 1 were gestation length (GL), calving ease (CE), birth weight (BW), gain on dam (GD) and 200-day weight (WW). Model 2 was used for gain on test (GT) and 365-day weight (YW). Mixed model techniques were used to obtain best linear unbiased estimates of BAX and BA from models 1 and 2, respectively. Hypothesis tests were conducted using two breed of dam groups ([Formula: see text] Simmental (S) and [Formula: see text] British breeds (B)) and four age of dam groups (2, 3, 4 and 5 + yr which correspond to < 31, 31–42, 43–54 and > 54 mo, respectively). Three-way subclasses (BAX) were significant (P < 0.01) for GL, CE, BW, GD and WW as were two-way subclasses (BA) for YW. Estimated differences for breed of dam by age of dam by six of calf subclasses (for GL, CE, BW, GD, WW) and breed of dam by age of dam subclasses (for YW) generally increased as age of dam increased. Accounting for breed of dam, age of dam, sex of calf and interaction effects are important in sire evaluation. Estimated differences of these effects, a by-product of sire evaluation, can be used to increase the accuracy of procedures for individual and dam evaluation. Key words: Breed of dam by age of dam by sex of calf effects, sire evaluation, mixed model techniques
POSTMORTEM CHANGES IN SOME OPTICAL, ELECTRICAL AND BIOCHEMICAL PROPERTIES OF ELECTRICALLY STIMULATED BEEF CARCASSES
Authors: SWATLAND H. J. , DUTSON T. R.
Published: March 2010

Thirty beef steers were slaughtered and their carcasses were split into left and right sides. Right sides were electrically stimulated and were compared to nonstimulated left sides for 24 h postmortem. Electrical capacitance was measured deep in the lumbar region of the longissimus dorsi with a spear-type electrode and a 100-kHz test current. Electrically stimulated sides had faster postmortem rates of decline in electrical capacitance, pH, and adenosine triphosphate (ATP) concentration. ATP concentration was correlated with capacitance (r = 0.88, P < 0.005) and with pH (r = 0.84, P < 0.005). At 24 h postmortem, the brightness of the longissimus dorsi was measured by absorbance at 650 nm using a fiber optic probe. Electrically stimulated sides had a lower absorbance than nonstimulated sides (0.62 ± 0.04 vs. 0.67 ± 0.04, respectively, P < 0.01). Data from the fiber optic probe were correlated with subjective evaluations of muscle brightness, r = −0.43, P < 0.005). In stimulated sides (but not in nonstimulated sides), the 0- to 3-h rate of capacitance decline postmortem was correlated with optical absorbance, r = −0.52, P < 0.005. Below pH 6, low capacitance was related to low ATP concentration. The effects of pH on capacitance were sporadic. Key words: Beef quality, electrical stimulation, physical properties
THE EFFECTS OF DIETARY MICRONUTRIENT, FAT AND PROTEIN COMPONENTS IN PELLETED FEEDS ON THE INCIDENCE OF SUDDEN DEATH SYNDROME AND OTHER TRAITS AMONG MALE BROILER CHICKENS
Authors: PROUDFOOT F. G. , HULAN H. W. , McRAE K. B.
Published: March 2010

Three experiments involving 11 600 male broiler chickens sought to determine if the pelleting process affects the dietary micronutrient, fat and protein components to increase the incidence of sudden death syndrome. Processed dietary micronutrient and fat components were not significantly associated with an increase in sudden death syndrome among broiler chickens. In one of the experiments, the incidence of sudden death syndrome was reduced (P < 0.01) when the dietary protein supplements (soybean meal, canola meal and fishmeal) bypassed the pelleting process. Key words: Sudden death syndrome, broiler chickens, feed pelleting, fat, micronutrients, protein supplements
SERUM CONCENTRATIONS OF LH, FSH AND PROLACTIN IN OVARIECTOMIZED EWES FOLLOWING TREATMENT WITH ANDROGENS OR ESTROGENS
Authors: HOWLAND B. E. , SANFORD L. M. , PALMER W. M.
Published: March 2010

The effect of a single injection of dihydrotestosterone, testosterone, testosterone propionate, estradiol-17β or estradiol benzoate on serum levels of luteinizing hormone, follicle stimulating hormone and prolactin was studied in ovariectomized ewes. Luteinizing hormone levels increased following treatment with E, EB or TP, prolactin levels increased following treatment with E, EB, T or TP while FSH levels decreased after treatment with either E or EB. Free steroids appeared to produce earlier responses in hormone levels than the corresponding esters. Key words: Androgens, estrogens, gonadotropins, prolactin, ewes.
ESTIMATION OF THE RUMEN DEGRADABILITY OF NITROGEN AND OF NONPROTEIN ORGANIC MATTER IN FORMALDEHYDE-TREATED AND UNTREATED CANOLA MEAL
Authors: BAILEY C. B. , HIRONAKA R.
Published: March 2010

The effect of formaldehyde on rumen degradability of the nitrogen and nonprotein organic matter in canola meal was assessed using dacron bags placed in the rumens of cows and assuming a fractional rate of passage of 0.06. With a diet of hay, degradabilities of total nitrogen, insoluble nitrogen, and nonprotein organic matter were 82%, 58%, and 57% in untreated meal and 21%, 6%, and 34% in treated meal. Key words: Canola meal, nitrogen, degradability, formaldehyde treatment
SELECTION LIMITS: HAVE THEY BEEN REACHED WITH PIGS?
Authors: FREDEEN H. T.
Published: March 2010

The likelihood of selection limits for performance traits of economic importance in pig production has been examined in the context of results from research with multiparous species and the context of the genetic improvement programs practiced in the industry. Research results with laboratory species (mice) have not identified insurmountable limits, either genetic or physiological, associated with intense unidirectional selection nor have such limits been identified in pig selection experiments spanning up to 12 generations. In terms of practical pig breeding this would represent approximately 25 yr. The evidence available on industry selection practices in Canada indicates that selection has been neither intense nor cohesive among breeders and that the criteria currently employed have been in place for less than one decade. For these reasons it appears that selection limits, if they exist, are unlikely to be evident for several more decades. This general outlook may not be applicable to all seed stock herds. Research evidence indicates that populations (e.g. fully closed herds) will show considerable individuality of response to selection which, coupled with variations among breeders in the intensity of selection and the performance criteria employed, will contribute to considerable divergence in the results obtained. While selection limits appear unlikely to compromise within-herd responses to sustained unidirectional selection, the universal adoption of specific criteria of performance merit, by fostering the progressive elimination of individual herds and breeds, diminishes the genetic flexibility of the population and restricts its potential to respond rapidly to changing production requirements. This aspect of genetic limits merits serious attention by the hog industry. Key words: Selection limits, pig breeding
INFLUENCE OF BREED, BIRTH DATE, AGE AND BODY WEIGHT ON LINEAR BODY MEASUREMENTS OF GROWING RAMS MAINTAINED IN A CONTROLLED ENVIRONMENT
Authors: SHRESTHA J. N. B. , HEANEY D. P. , FISER P. S. , LANGFORD G. A.
Published: March 2010

Heart girth (HG), body length (BL), leg length (LL), metacarpal circumference (MC), withers height (WH) and hook width (HW) of 233 growing rams of three synthetic strains, Suffolk and Finnsheep breeds were measured at 6, 8 and 10 mo of age. Thereafter, subsequent measurements were taken at 11–13 mo, 18–21 mo and 23–25 mo of age. Breed, birth period (hysterectomy derived birth date), age of ram and body weight (BW) had important effects (P < 0.05) on linear body measurements, whereas age of dam did not (P > 0.05). Significant effects of litter size on HG and BL were observed at 6 and 8 mo of age, respectively. All linear body measurements increased from 6 to 21 mo of age, whereas BL, WH and HW continued to increase to 25 mo. Rams of Strain 1, developed as a synthetic sire strain, with a large proportion of Suffolk background were generally similar to the Suffolk rams in all body measurements except for HG which was significantly larger than in Suffolk rams. The Finnsheep rams had smaller HG, BL, MC and HW than the synthetic strains and Suffolk rams, whereas LL and WH of the Finnsheep and Suffolk rams were similar. Rams of Strains 2 and 3, developed as synthetic dam strains with 50 percent Finnsheep background, were similar in body measurements. The synthetic dam strains did not differ from Strain 1 and/or Suffolk with respect to HG, BL, WH and HW. However, Suffolk rams had larger MC and shorter LL compared to those of the Strain 2 and 3 rams. Birth period had a significant effect on HG, BL, LL and MC, but no consistent trend with age of ram was apparent. Linear body measurements were positively correlated with each other and with body weight; however, the relationship varied as rams progressed in age. The importance of breed, birth date, age of ram and body weight on body measurements and the requirements for appropriate adjustments is emphasized. Key words: Sheep, body measurements, breed, birth date, age of ram
DIFFERENCES IN CARCASS TRAITS OF THREE BREEDS OF SWINE AND CROSSES AT FIVE STAGES OF DEVELOPMENT
Authors: McKAY R. M. , REMPEL W. E. , CORNELIUS S. G. , ALLEN C. E.
Published: March 2010

Carcass measurements from 249 pigs representing all possible two-breed crosses of Minnesota No. 1 (M), Pietrain (P), and Yorkshire (Y) breeds were recorded following slaughter at five developmental stages (35 days of age, 22.5 kg, 45.0 kg, 67.5 kg, and 90.0 kg liveweight). The objectives were to determine how advancing maturity affected reciprocal differences and heterosis, to examine breed differences, and to calculate growth curves for these measurements. Three distinct patterns were observed for reciprocal differences. The first was an increase in magnitude, the second parabolic, and the third a decrease in magnitude. Statistically significant heterosis estimates were too few to allow for an examination of trends associated with advancing maturity. The following breed differences were found: (M = Y)>P for carcass length, M>(P = Y) for mean backfat thickness, P>Y>M for loin eye area, ham weight, boned ham weight, semitendinosus weight, biceps femoris weight, and semimembranosus weight, (P = Y)>M for loin weight, shoulder weight, biceps brachii weights, femur weight, and ham and loin percentage, and Y>(M = P) for humerus weight. The growth curves indicated that 80% of total carcass length was achieved by 45.0 kg, mean backfat thickness, loin eye area, femur weight, and humerus weight had 80% of their growth completed by 67.5 kg, and boned ham weight, loin weight, shoulder weight, biceps brachii weight, ham weight, semitendinosus weight, semimembranosus weight, and biceps femoris increased directly proportional to liveweight. Key words: Reciprocal differences, heterosis, breed differences, carcass, growth curves, pigs
INJECTABLE Cu COMPLEXES AS SUPPLEMENTARY Cu FOR GRAZING CATTLE
Authors: BOILA R. J. , DEVLIN T. J. , DRYSDALE R. A. , LILLIE L. E.
Published: March 2010

Four preparations of copper (Cu) salts, CuCaEDTA, Cu glycinate from two manufacturers, one in New Zealand (NZ) and the other in the United States (US), and Cu methionate were evaluated as injectable sources of Cu for cattle grazing pastures at four sites in Western Manitoba. There were four treated and one untreated groups of cattle at each site. Treated cattle were injected subcutaneously into the side of the neck. The concentration of Cu in blood serum, as an indicator of Cu status, was measured at 0, 30, 60 and 90 days post-injection. The area that was affected by the volume of swelling at the site of injection, as evaluated 30, 60 and 90 days post-injection, was a measure of the severity of reaction encountered: less than 25 cm2, moderate; 25–50 cm2, moderately severe; greater than 50 cm2, severe. At day 30 with 276 cattle, and day 90 with 133 cattle, serum Cu was higher (P < 0.05) in treated than untreated cattle, but there was no difference (P > 0.05) between Cu preparations. Responses of serum Cu to injectable Cu preparations were related to the severity of Cu deficiency in cattle on day 0, and to calculated absorption coefficients for Cu and available Cu in forages consumed by cattle at each site. At 30 days post-injection, the percent of cattle with a reaction at the site of injection (severity in brackets) was: CuCaEDTA, 6% (moderate); Cu glycinate (NZ), 23% (moderate); Cu glycinate (US), 48% (moderate to moderately severe); Cu methionate, 89% (moderate to severe). Areas up to 250 cm2 were affected with Cu methionate. At 90 days moderate reactions were only present with Cu methionate. Body weight at day 90 was not influenced (P > 0.05) by injectable Cu. Although the preparations had similar effects upon serum Cu the severity of reaction at the site of injection may mitigate against the use of some preparations. Key words: Cattle, injectable copper, copper calcium edetate, copper glycinate, copper methionate
FEED UTILIZATION: PRINCIPLES AND NEW DEVELOPMENTS IN PHYSIOLOGY
Authors: PHILLIPS G. D.
Published: March 2010

Feed efficiency should be taken in a wider context than the familiar feed to gain ratios which are used extensively. For the producer it is total cost of the feed versus the value of the product which is of ultimate concern. Improving feed cost efficiency can be achieved, for instance, by improving reproductive performance or by producing a product which has a higher market value, neither of which may necessarily increase the cost of feed. In considering feed utilization per se there are several levels of activity which may be subject to manipulation to improve efficiency. Administration of hormones, or hormone-like substances has long been in vogue. Some have proved useful such as estrogenic and androgenic agents whereas thyroproteins have not been proven to be of value. Growth hormone alone and in its interactions with somatostatin or insulin hold promise for improved feed efficiency. Another area of current interest is that of the neurohormonal system involving, for instance, the hypothalamic secretions and melatonin. Biotechnology processes such as gene transfer and cloning are creating much excitement. Genetic engineering of rumen, or extra ruminal, microorganisms may well become factors in improving feed efficiency. Key words: Feed efficiency, nutrient utilization, growth hormone, biotechnology, digestive efficiency
MORPHOLOGIC ASPECTS OF DYSTOCIA IN DAIRY AND DUAL PURPOSE HEIFERS
Authors: MEIJERING A. , POSTMA A.
Published: March 2010

The phenotypic association between ease of calving and a number of, mainly morphologic, dam traits was examined by stepwise discriminant analysis. Body weight, body dimensions and scores for fat covering and muscularity were obtained for 79 Holstein (H), 90 Dutch Red and White (DRW) and 104 Dutch Friesian (DF) heifers at 10 days after calving, Dimensions were body length, height at hips and withers, width and depth of chest, heart girth, hip width and spiral girth. About half of the heifers had data on precalving pelvic dimensions, both internal (height and width of pelvic inlet) and external (width at hips and thurls, pinbone distance, horizontal and vertical distances between hip and thurl, and hip and pinbone). Birth weight of all, and body dimensions of live calves were recorded. Calving ease was scored as 'easy' (no or minor assistance), 'normal' (easy pull) or 'difficult' (hard pull or Caesarean). In addition, forces exerted by a calf puller were recorded in a number of easy, normal and difficult deliveries. Analysis of these forces indicated that classification as 'easy' vs. 'normal' was more influenced by subjectivity or chance than 'normal' vs. 'difficult'. Birth weight and almost all calf dimensions were significantly related to ease of calving. All simple relationships involving dam traits lacked significance in H and DF heifers, except precalving hip width in the latter group. DRW heifers experiencing difficult calving were on average heavier and larger framed. Excluding calf dimensions, birth weight was the first variable to enter into the discriminant functions in all three breed groups. Dam traits contributing to discrimination between calving performance categories were depth of chest in H heifers, heart girth, chest width and pinbone distance in DRW heifers, and pelvic height in DF heifers. The possible significance of these effects is discussed. Key words: Dystocia, discriminant analysis, dam traits, dairy cattle
FEEDLOT PERFORMANCE, CARCASS COMPOSITION AND EFFICIENCY OF MUSCLE GAIN IN BULLS AND STEERS OF DIFFERENT MATURE SIZE SLAUGHTERED AT SIMILAR LEVELS OF FATNESS
Authors: JONES S. D. M. , BURGESS T. D. , WILTON J. W. , WATSON C. H.
Published: March 2010

Feedlot performance, carcass composition and efficiency of muscle gain were compared in 33 young beef bulls and 33 beef steers of different mature body size (35 small or mainly British breed crosses; 31 large or Continental crosses). All cattle were fed a high-energy diet based on corn silage and high-moisture corn from weaning to slaughter. Slaughter was carried out once 6 mm of fat was attained over the 11/12th ribs determined ultrasonically. Large crossbred animals had higher average daily gains, greater slaughter weights and spent longer time on feed than small crossbred animals and bulls. Similar results were found for all bulls compared to all steers. Feed conversion rate expressed on a live weight basis was superior for small crossbreds compared to large crossbreds, but there were no corresponding differences between bulls and steers. At the same proportion of dissected carcass subcutaneous fat, carcasses from large crossbreds and all bulls had greater proportions of muscle, less bone and similar proportions of total fat than small crossbreds and all steers. There were generally no differences for gender and size in the distribution of muscle within each of the wholesale cuts except in the case of the chuck, where bull carcasses had a greater proportion of muscle compared to those from steers. Bone distribution, however, did vary significantly across several wholesale cuts with carcasses from large animals and bulls having lower proportions of bone than those from small animals and steers. Feed conversion rate (g muscle/kg DM) was superior for bulls compared to steers (63 and 56 g muscle/kg DM, respectively), but similar for large and small animals (60 and 59 g muscle/kg DM, respectively). The present data suggest that the evaluation of beef cattle for feed efficiency on a liveweight and muscle basis may yield different conclusions. There were no significant size × castration interactions for any of the growth, efficiency and carcass variables examined. Key words: Beef, mature size, castration, carcass composition, efficiency