Showing papers in "Canadian Journal of Animal Science in 1971"

Copper to molybdenum ratio and molybdenum and copper concentrations in ruminant feeds

Abstract: Molybdenum and Cu concentrations and Cu/Mo ratios were determined on samples of legume hay, grass legume hay, grass hay, sedge hay, oat forage, corn silage and grains throughout British Columbia. In addition, the relationships between Cu distribution and both Mo concentration and the Cu/Mo ratio were determined for all feeds. The critical Cu/Mo ratio was selected as 2.0, and samples with ratios below 2.0 would be expected to cause conditioned copper deficiency. Sedge hays had a mean Cu/Mo ratio of 2.1, which was less than half the mean ratio of 4.4 for grass hays. The mean ratios for the other classes of feed were 5.0 or higher. Notwithstanding the favorable mean ratios, 19% of all samples had ratios below 2.0. The lowest Cu/Mo ratio was 0.1 and the highest was 52.7, which shows extreme variability. Molybdenum concentrations were generally low, with 35% of all samples below 1 ppm Mo. There were no unusually high Mo concentrations, as only 1% of all feeds were above 8.0 ppm Mo and the highest value was 9.9...

Causes of mortality in yorkshire pigs from birth to 20 weeks of age

Abstract: The mortality rate in 6890 Yorkshire piglets from birth to 20 weeks was 25.6%, of which 7.2% occurred at farrowing, and 16.4% from birth to weaning. The average number of mummified or decomposed pigs was 0.13 per litter. Of the total mortality, 15.3% occurred on the first day and 43.7% occurred during the first week. Major causes of death were: general congenital weakness and inanition, 26.9%; overlain or bitten by dam, 19.2%; scours, 14.2%; and paralysis, 10.2%. When inbreeding increased from less than 5% to 25% and over, mortality before birth went from 5.9% to 14.1%, and before weaning from 15.1% to 20.9%. No significant effect of farrowing quarters on mortality was detected, but there were significant effects of fines and years. Curvilinear relationships between average pig weight, litter size and mortality were fitted, and maximum rates were calculated. A linear relationship was observed between the survival at weaning and the within-litters coefficient of variation of pig weights at birth.

A rapid micro-digestion procedure for neutral and acid detergent fiber.

Abstract: A micro-digestion procedure for the determination of neutral (NDF) and acid detergent fiber (ADF) employing 0.35 g of sample was developed. Four roughages and corn grain were digested by the standard Van Soest macro acid and neutral detergent fiber methods, and by the micro method. Differences between two-thirds of the means for NDF and ADF, as determined by the two methods, were statistically significant (P < 0.05). Absolute differences between means for all samples analyzed were small, with a range from 2.82 to 1.41 percentage units for NDF and 0.85 to 0.14 percentage units for ADF. Neutral detergent fiber determinations of corn grain were completed without filtration problems when the micro-digestion method was employed, in contrast to the difficult filtrations encountered with the macro method. Standard deviations of means for samples digested by the micro method were small except for corn grain.

Study of the mechanism of inhibition of ketogenesis by propionate in bovine liver

Abstract: Propionate caused an inhibition of ketogenesis from butyrate by bovine liver slices. When succinate, fumarate and aspartate were included in the incubation mixtures as sources of oxaloacetate, they were not as inhibitory as propionate. The possibility of competition between propionate and butyrate for cofactors required for activation was discounted when neither ATP (17 mM), nor carnitine (3.5 mM), added to expand the coenzyme A (CoA) pool, relieved the antiketogenic effect of propionate. The 3-hydroxy-3-methylglutaryl-CoA pathway appeared to be the major route for formation of acetoacetate from acetoacetyl-CoA in liver extracts, on the basis of enzyme assays. At a concentration of 0.5 mM, propionyl-CoA caused an apparent decrease of 3-hydroxy-3-methylglutaryl-CoA synthase activity of 46%, whereas propionate and methylmalonyl-CoA were not effective. At a concentration of 15 mM, propionate resulted in 30% inhibition of synthase activity. Propionyl-CoA did not affect the activity of 3-hydroxy-3-methylglutar...

Digestible and metabolizable energy values of some feeds for the growing pig

Abstract: Digestible energy (DE), metabolizable energy (ME) and metabolizable energy corrected to nitrogen equilibrium (MEn) were determined for eight feeds. Effects of protein level in the basal ration and ...

Preliminary evaluation of the addition of glucogenic materials to the rations of lactating cows

Abstract: Glutamate, succinate, propylene glycol, or glycerol were added to a basic concentrate at 33% of air-dry feed Each concentrate was fed both ad libitum and in restricted amounts to four cows in early lactation Dietary intake, milk yield and composition, molar proportions of rumen volatile fatty acids and blood glucose, ketones and plasma free fatty acids were used as criteria of effect of these supplements Propylene glycol in the diet resulted in a lower intake of concentrate compared with glycerol (1144 versus 1430 kg/day) and significantly decreased (P < 005) rumen butyrate and plasma beta-hydroxybutyrate Glutamate supplementation prevented the fall in milk fat content which occurred when the other three supplemented concentrates were fed ad libitum, and this effect may have been related to the constancy in the ratio of acetate to propionate in the rumen fluid

Bilateral ectrodactyly and spinal deformation in a mixed-breed dog

Abstract: A 3-year-old, female mixed-breed dog had malformations of both thoracic limbs and the vertebral column. Radiographs of the forelimbs showed bilateral development of 2 digits and aplasia of 3 carpal bones. Kyphosis, scoliosis, and deformed vertebrae were present in the thoracolumbar vertebral column.

Characteristics of youthful beef carcasses in relation to weight, age and sex: iii. meat quality attributes

Abstract: A total of 574 youthful beef carcasses from three sources comprising 168 steers, 147 heifers and 259 bulls were processed to study the influence of carcass weight, age and sex on beef quality. Source differences in pre-slaughter treatment were associated with differences in ultimate pH and in color of the longissimus dorsi muscle. Dark color and high pH values (pH > 6.0) were characteristic of the 1. dorsi muscle from bulls subjected to the greatest pre-slaughter stress. Stress effects markedly influenced palatability factors, with dark-colored bull beef from this one source scoring significantly higher for tenderness, juiciness and flavor than beef from steers subjected to the same pre-slaughter treatment. For these bulls the correlation between tenderness and meat color score was −0.50. Comparisons within source groups indicated that in meat color and shear values at 72 hr post mortem, heifers were superior to bulls and inferior to steers. After excluding the stressed (high ultimate pH) bulls from one s...

Digestibility of sodium hydroxide-treated straw fed alone or in combination with alfalfa silage.

Abstract: Rations were fed at a constant level of dry matter intake to eight wethers in a double 4 × 4 Latin square design. Cell walls and energy of wet barley straw treated with sodium hydroxide (NaOH) at 100 C were more digestible (P < 0.01) than with alfalfa silage. Mixing treated straw with alfalfa silage resulted in associative effects on digestibility, particularly with the lowest level of straw in the ration. Assuming the digestibility of alfalfa silage to remain constant, treated straw was 11.4 units higher in energy digestibility when fed at a level of 22% compared with 80% of dry matter intake. Increased cellulose digestibility accounted for only part of this improvement. Sheep fed mainly NaOH straw consumed the least nitrogen but had the highest nitrogen retention (P < 0.01). Marked increases in water intake and urine output occurred with sheep fed high levels of treated straw. With all rations, the majority of ingested sodium was excreted in the urine.

Chronic mesenteric volvulus in a dog.

Abstract: The data were taken from 2,534 Holstein herds on Record of Performance (ROP) for milk Herd size was determined from the average inventory of cows on July 1, 1967 and July 1, 1968 Herd production was obtained for cows with records from March 1, 1967 to February 29, 1968 The cows disposed of from September 1, 1967 to August 31, 1968 were recorded in three main sections: (1) cows sold for beef, (2) cows sold for dairy purposes, and (3) cows that died in the herd Section 1 was divided into four subsections: cows sold due to breeding or calving problems, low production, unsatisfactory type, and other reasons Herds were categorized as constant, increasing, or decreasing in size Within each size grouping and disposal reason, multiple regression analyses were completed for percent of cows disposed of in relation to herd size and production level In herds of constant size, production level increases were associated with increases in total percent of cows disposed of (P < 001), increases in percent sold

Tissue development in swine as influenced by liveweight, breed, sex and ration.

Abstract: Carcasses of 73 pigs taken from an experiment which involved 144 barrows and gilts of Duroc × Yorkshire, Hampshire × Yorkshire and Yorkshire × Yorkshire breeding, fed either a high energy (HE) (3652 kcal DE/kg) or a low energy (LE) (2757 kcal DE/kg) ration, and slaughtered at 68, 91 and 114 kg liveweight, were dissected to study tissue development and carcass composition in pigs. To establish a starting point, an additional nine barrows and eight gilts of the same breed groups were slaughtered at 23 kg liveweight. A normal pattern of tissue growth was shown to occur, bone growth being relatively slow and muscle growth relatively fast. Fat deposition paralleled muscle growth from 68 to 91 kg liveweight, after which fat deposition exceeded muscle growth in absolute amount. Breed of sire tended to influence the carcass, muscle and fat weight per day of age as well as the proportions of lean and fat in the carcass. Gilts had more muscle per day of age and a greater percentage of muscle and less of fat than ba...

Interaction of strain, density and ration with two light systems on broiler performance.

Abstract: Two experiments were conducted to determine the effect of continuous and intermittent (1 hr on and 3 hr off) light treatments and the influence of strain, density and ration on performance of broilers maintained on each light treatment. Three thousand and six hundred broilers of two strains were grown with 0.093 m2 and 0.047 m2 of floor space per bird in experiment 1. Three thousand broilers from one strain were grown with 0.093 m2 of floor space per bird in experiment 2; 600 birds were fed each of five test rations. Body weight, mortality and feed efficiency were calculated in both experiments and slaughter grade was determined in experiment 1. Birds grown on intermittent light had lower mortality and better feed efficiency than those on continuous light. Average body weight at 7 weeks of age was not significantly different for the two light treatments; however, significant interactions were observed for strain × light, density × light and ration × light. Light treatments did not affect the percentage of...

Factors influencing milk yield of beef cattle

Abstract: The joint and separate effects of several cow-calf variables on milk yield were studied with 176 and 201 beef cows from the University of Alberta beef breeding herd for 1966 and 1967, respectively. The dams consisted of Hereford, Aberdeen Angus, Galloway and hybrid breeding. Independent variables considered were: breed, post-calving weight, winter weight loss, summer weight gain and age of dam, and weaning age, sex and birth weight of calf. Total variance of milk yield explained by all variables together was only 40 and 52% for 1966 and 1967, respectively. Breed and age differences of dam accounted for 82 and 87% of explained variance in milk yield respectively for 1966 and 1967. Holding cow age constant, post-calving weight of cow explained 0.0 and 8.5% additional variance in milk yield for 1966 and 1967, respectively. Summer weight gain of cow was negatively associated with milk yield. Winter weight loss of cow had little influence on milk yield. There appeared to be a negative relationship between earl...

A nutritional comparison of various rapeseed and mustard seed solvent-extracted meals of different glucosinolate composition

Abstract: Seven solvent-processed meals from Brassica napus, B. campestris and B. juncea seed, were compared with soybean meal in a replicated factorial experiment involving three levels of meal (5, 10 and 20%), with and without a flavoring mixture, with and without dietary myrosinase, in a feeding trial with male weanling mice. The addition of 0.3% myrosinase improved the digestibility of both protein and energy fractions, but resulted in growth depression in diets containing meals high, in glucosinolates and fed at 10 or 20% levels. Removal of feed intake differences by regression methods revealed that non-hydrolyzed glucosinolates in diets containing 10% Brassica meals had little effect on growth rate, except for one B. napus meal high in 2-hydroxy-3-butenyl glucosinolate. Diets containing glucosinolates giving rise to allyl- and butenyl isothiocyanates, as well as oxazolidinethione, inhibit growth; therefore, total glucosinolate content should be considered in assessing the nutritional value of Brassica meals.

Loss in digestible nutrients when ensiled barley is fed whole.

Abstract: Two experiments were conducted to determine the proportion of whole and milled ensiled barley which passed through the digestive tract of cattle. Four three-year-old Holstein steers were used in a 4 × 4 Latin square design. Six kg/day of whole barley or barley milled through a hammermill with a 1.3-cm diameter screen was fed either as the sole ration or with 2 kg/day of long hay. Milling the barley resulted in a 25 to 30% increase in the digestion coefficients for dry matter, organic matter and energy. The whole barley kernels recovered from the feces were similar to the barley as fed in chemical composition and in vitro dry matter digestibility. Feeding hay did not increase the digestion of barley in spite of increased rumination. Whole barley recovered from the feces was only 15% of that consumed by four yearling heifers in a switch-back experiment. The barley recovered was lower in in vitro dry matter digestibility than the barley as fed. It was concluded that the younger animals chewed the whole barle...

Puberty, post-weaning estrus and estrous cycle length in yorkshire and lacombe swine

Abstract: Age at puberty in gilts and the number of days from weaning to estrus were determined on 132 gilts and 370 primiparous sows. The average age at puberty was 197.5 ± 1.8 (SE) days, in a range of 141 to 254 days. In this study, Yorkshire sows averaged 5.5 ± 0.3 days and Lacombe sows 14.3 ± 0.8 days to estrus after weaning (P < 0.001). In the first week after weaning, 90.5% of the Yorkshire sows and 48.0% of the Lacombe sows returned to estrus. One Yorkshire sow (0.5%) and 35 Lacombe sows (20.2%) failed to show estrus by 28 days after weaning. Yorkshire females had an average estrous cycle length of 21.0 ± 0.2 days, and Lacombe females 21.7 ± 0.1 days (P < 0.05).

Energy utilization by the lacombe and yorkshire breeds of pig

Abstract: A comparative slaughter trial involving 32 weanling pigs was conducted to estimate the energy requirements for maintenance and production and to compare the energetic efficiency of Lacombe and Yorkshire pigs. The coefficients of digestible energy (DE), metabolizable energy (ME), and ME/DE ratio were similar for the two breeds. The fasting heat production and energy requirements for maintenance of energy equilibrium for the Yorkshire pigs were significantly higher (P < 0.01) than for the Lacombe pigs. Differences in the efficiency of utilization of ME for the function of maintenance and for production were not significant. Estimates of net energy for maintenance and net energy for gain of the corn-soybean meal diet are presented. The study suggests that these net energy values, like the DE and ME values, may be used for diet formulation without need for correction for breed. The use of the exponent 0.56 rather than 0.75 as the reference base of metabolic body size led to increased precision, as indicated b...

Evaluation of milk variables as measures of milk effect on preweaning performance of beef cattle.

Abstract: A study with 176 (1966) and 201 (1967) cows from the University of Alberta beef herd was conducted to investigate the effectiveness of a number of milk variables for explaining variance in preweaning gain of beef calves. The seven milk variables calculated over 24 hours were yield of milk, total energy, total protein and total solids, and percentages of butterfat, protein and solids-not-fat. These variables were measured for two periods, August and October, and averages for the two periods were calculated. Mean 24-hour milk yield ranged from 3.8 to 6.1 kilograms. Percentage of butterfat, protein and solids-not-fat, respectively, ranged from 4.10 to 5.77, 3.28 to 3.93, and 8.67 to 9.50. The intercorrelations among yield of milk, energy, protein and total solids were high and positive, ranging between 0.85 and 0.99. Correlations of milk yield with percent milk components were small and predominantly negative. Intercorrelations of percent milk components ranged from 0.09 to 0.55. Correlations of mean milk yi...

Enzymes of ketogenesis in bovine rumen epithelium

Abstract: The activities of various enzymes involved in formation of acetoacetate from acetoacetyl-coenzyme A (acetoacetyl-CoA) were investigated using crude extracts of rumen papillae. Acetoacetyl-CoA deacylase and 3-hydroxy-3-methylglutaryl-CoA synthase were measurable in these extracts, but addition of succinate (15 mM) produced an increased activity of acetoacetyl-CoA removal which was up to threefold, or more, that of deacylase. Succinyl-CoA was identified as a product of the reaction in the presence of succinate, indicating that 3-oxo acid CoA transferase was present in the papillae. The maximum activities of synthase, deacylase, and transferase were 16, 14, and 70% of the total capacity to remove acetoacetyl-CoA, respectively. The possible physiological significance of the participation of 3-oxo acid CoA transferase in ketogenesis in rumen epithelium was discussed.

Fat distribution in swine as influenced by liveweight, breed, sex and ration

Abstract: The effects of liveweight, breed group, sex and plane of nutrition were studied in 23 Duroc × Yorkshire, 42 Hampshire × Yorkshire and 27 Yorkshire × Yorkshire barrows and gilts fed either a low or high energy ration [2757 kcal digestible energy (DE)/kg and 15.3% protein, or 3652 kcal DE/kg and 19.9% protein]. They were slaughtered at 68, 91 or 114 kg liveweight. Nine barrows and 8 gilts of the same breed groups were slaughtered at 23 kg liveweight to determine carcass composition at the start of the experiment. Half-carcasses were divided at the 11th and 12th ribs and dissected into individual muscles, depot fats and bones. Fatty tissue was separated into subcutaneous, intermuscular and body cavity types of depot fat. As liveweight increased from 23 to 114 kg, a differentiation among depot types occurred. Fat distribution in 23-kg pigs was made up of 78% subcutaneous, 18% intermuscular and 4% body cavity fat. At 114 kg liveweight, subcutaneous fat was 84%, intermuscular fat 13% and body cavity fat 2.3%. W...

Digestible and metabolizable energy values for rapeseed meals and for soybean meal fed to growing pigs.

Abstract: Twelve samples of rapeseed meal (RM) and one sample of soybean meal (50% protein) (SM) were evaluated for digestible energy (DE), metabolizable energy (ME), nitrogen-corrected ME (MEn) and digestible nitrogen (DN). RM samples were of Brassica campestris and B. napus origin and contained meals processed by solvent, prepress-solvent or expeller processes. Two of the meals were from rapeseeds not in commercial production, one a Bronowski (low glucosinolate) napus meal and one a meal from zero-erucic acid rapeseed of napus type. Energy studies were conducted with 64 pigs at 16, 33 and 65 kg liveweight, adding 25% by weight of the test ingredient to the total diet. The overall means and standard errors for all weight groups for gross energy (GE), DE, ME and MEn, in kcal/g of dry matter, for 10 RM (excluding Bronowski and zero-erucic acid RM) were 4.74 ± 0.12, 3.21 ± 0.18, 2.89 ± 0.19 and 2.64 ± 0.19, respectively, while the values obtained for SM were 4.81 ± 0.08, 4.21 ± 0.16, 3.92 ± 0.17 and 3.64 ± 0.16. Ther...

Fetal mortality in the prepuberal gilt

Abstract: Forty prepuberal gilts weighing from 45 to 55 kg were injected with 1000 IU of pregnant mare’s serum (PMS), followed 48 hours later by an injection of 500 IU of human chorionic gonadotrophin (HCG) and 10 mg of diethylstilbestrol (DES). They were inseminated 24 hours after the HCG and DES injections. Ten gilts killed four days after insemination ovulated a mean of 18 ova; 91% of the ova recovered were fertilized, of which 81% were in the morula stage and undergoing normal cleavage. A mean daily oral intake of 26.4 mg of chlormadinone acetate (CAP) and 52.8 μg of DES per gilt, commencing seven days after insemination, appeared to assist in the maintenance of pregnancy early in gestation, as seven of nine gilts killed at 20 days of gestation were pregnant (anatomical abnormalities were found in the other two gilts) whereas a similar intake of hormones failed to maintain pregnancy in 15 gilts slaughtered 50 days after insemination. Similarly, six gilts administered 1000 IU of PMS and 500 IU of HCG at 9 and 11...

Amino acid digestibility of rapeseed meal fed to chickens: effects of fat and lysine supplementation

Abstract: An experiment was carried out to evaluate the amino acid digestibility of commercial rapeseed meal fed at a level of 30% as the only source of protein in the diet of chickens. The effects of supplementing the experimental diets with 3.5% vegetable fat or 0.25% L-lysine were also investigated. Each diet was fed ad libitum to four colostomized chickens, housed in individual cages. At the end of the experiment, a protein-free diet was fed to permit the measurement of true digestibility. The results showed that the digestibility coefficients for 16 amino acids of rapeseed meal ranged from 44 to 72% and from 63 to 80% for the apparent and true digestibility coefficients, respectively. Of the dietary supplements used, fat caused a greater increase in amino acid digestibility than did L-lysine.

Crossbreeding swine: reproductive performance of seven breeds of sows bred to produce crossbred progeny

Abstract: Data were obtained from 57 Yorkshire (Y), 44 Landrace (LD), 39 Lacombe (LC), 34 Hampshire (H), 21 Duroc (D), 19 Berkshire (B), and 7 Large Black (LB) gilts farrowing crossbred litters by LD, LC, H, D, B, LB and Tamworth (T) boars in a half polyallel mating design. The traits studied were weight at puberty, number of normal teats, number of services per conception, gestation period, litter size and weight at birth, 21 days and weaning (35 days), average pig weight, mortality rate at birth and during suckling, and change in dam’s weight during nursing. The effect of breed of dam was significant (P < 0.01) on all traits studied except weight at puberty, number of services per conception and mortality rates at birth and during suckling. Gestation period was significantly longer for B, LB and Y than for sows of other breeds. LB sows had the smallest and B the lightest litters, while the largest and heaviest litters at birth, 21 days and weaning were those from LC and Y sows. LC, LD and Y sows had more teats an...

Effect of continuous feeding of rapeseed meal on growth of dairy calves and subsequent first lactation yield.

Abstract: Thirty dairy heifer calves were reared from birth to calving on rations containing 0, 6.8 or 13.7% rapeseed meal in substitution for soybean meal. The level of rapeseed meal did not significantly (P > 0.05) affect feed intake, weight gain or feed efficiency of heifers up to breeding weight (330–340 kg). The level of rapeseed meal did not significantly (P > 0.05) affect reproduction or milk production during the first lactation. However, there may have been a trend for lower conception rate and milk fat production during first lactation with the higher level of rapeseed meal.

Selenium content of some feed ingredients available in Canada.

Abstract: The selenium content of Canadian grains, wheat by-products, plant and animal protein supplements and mineral supplements has been determined by chemical analyses. Grains of prairie province origin contained five to ten times as much Se as those of Ontario and Quebec. Corn, oat, barley and wheat grain from the latter central provinces had low and comparable levels of Se; western durum wheat had a high level. Plant products varied widely in their Se content, soybean meal being low (0.14 ppm), rapeseed and linseed meals high (ca. 1.00 ppm). Among animal products, milk by-products contained the least amounts (ca. 0.15 ppm) and fishery products the most (ca. 2.00 ppm). Meat and poultry products had intermediate amounts. Calcium phosphate (0.65 ppm) contained 15 times as much Se as calcium carbonate.

Factors affecting preweaning performance in beef cattle

Abstract: Two years data involving 176 and 201 cows from the University of Alberta beef breeding herd were used to study the influences on calf preweaning performance of: breed, age, weight, summer and winter weight changes and milk yield of dam; breed of sire; and birth weight, weaning age and sex of calf. All independent variables combined explained 73 and 70% of total variance in average daily gain (ADG) to weaning and 81 and 70% of total variance in weaning weight, respectively, for 1966 and 1967. Of all variables considered, milk yield had the greatest influence on preweaning performance, explaining about 60% of the variation in ADG to weaning and 40 to 50% of the variation in weaning weight. A 1-kg increase in daily milk yield resulted in an 11- to 14-kg increase in weaning weight. Breed of dam explained about 23% of total variance in ADG to weaning, most of which was accounted for by breed differences in milk yield. Breed-of-sire differences accounted for 5.7 and 1.4% of variance in ADG of progeny for 1966 a...

Feeding high levels of rapeseed meal to pregnant gilts

Abstract: Eleven crossbred gilts were allotted at random to two dietary treatments containing either 0% or 12% solvent-extracted rapeseed meal (RSM) of Chilean origin as the main source of supplemental protein in the diet The RSM, of Brassica napus type, contained 41 mg isothiocyanates per g meal The experiment, which covered the periods of pregnancy and lactation, was started immediately after mating and terminated 3 weeks after birth Results indicated that gilts fed 12% RSM during pregnancy gained significantly less with the same feed allowance (2 kg per day) than the fish meal (FM) group Total litter size and weight at birth were similar for both treatments However, only 49% of the piglets were born alive from the gilts fed the 12% RSM diet; thyroid glands of live and stillborn piglets were markedly enlarged and symptoms of iodine deficiency were clearly manifested Most pigs died within 72 hours after birth and four of the seven gilts lost their whole litter during this period Of total pigs born to RSM-f