bluuebunny/crossref_metadata_2025 huggingface dataset:
EFFECT OF FEED ADDITIVES ON CALCIUM REQUIREMENT, CALCIUM RETENTION AND SHELL CALCIFICATION IN THE LAYING HEN
Authors: HULAN H. WINSTON , NIKOLAICZUK N.
Published: March 2010

Calcium retention studies were undertaken with 14-month-old Single Comb White Leghorn hens at summer temperatures to determine the optimal ration calcium level for maximum retention and shell calcification. Thereafter, the effects of three ration additives, arsanilic acid (Pro-Gen) 90 ppm, neomycin sulfate (Pre-mix) 200 ppm, and bacitracin (Fortracin) 200 ppm, on calcium retention and shell quality were studied at near-optimal ration calcium (2.66%). Results indicated that 2.66–2.70% ration calcium was adequate for hens laying at rates of 75–80%, but a somewhat higher level (e.g., 3.15%) will ensure better quality eggshells. The hens receiving a level of 2.40% ration calcium displayed a significantly higher (P < 0.01) percent calcium retention but a significantly lower (P < 0.01) eggshell quality than did the hens receiving the 3.15% ration calcium. The groups fed 2.66 and 3.15% calcium displayed significantly higher (P < 0.05) calcium retention per egg laid than did the groups fed 2.40 or 2.91% ration calcium. Calcium retained per egg laid was increased by the additives, but the increases were not significant (P < 0.05).
COPPER TO MOLYBDENUM RATIO AND MOLYBDENUM AND COPPER CONCENTRATIONS IN RUMINANT FEEDS
Authors: MILTIMORE J. E. , MASON J. L.
Published: March 2010

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 ppm. Copper concentrations were low. Fourteen percent of all samples were below 3.0 ppm and 95% of all samples were below 10.0 ppm. Legume feeds had a mean Cu concentration of 7.5 ppm, in contrast to sedge hays which had a mean concentration of 3.3 ppm Cu. As Cu concentrations increased in all feeds the Cu/Mo ratios also increased, when all feeds were considered in one compilation. Molybdenum concentrations were high, then decreased, but increased to the same high concentrations as Cu concentrations increased. These data indicate an unexpectedly high and nutritionally important variability in Cu/Mo ratios, and add further support to our previous report of extensive low levels of Cu. Both Cu and Mo analyses are required to predict the need for Cu supplementation. This appears to be the first extensive report on Cu/Mo ratios in feeds.
BARLEY SILAGE, GROUND WHOLE PLANT BARLEY AND CORN SILAGE FOR FINISHING BEEF CATTLE
Authors: MOWAT D. N. , SLUMSKIE R. A.
Published: March 2010

Barley silage (mid-dough), mature, dry-ground, whole-plant barley, and corn silage were evaluated for growing and finishing steers over two consecutive crop years. Adequate supplemental protein was provided. Steers fed barley silage gained the least and required the most feed dry matter per unit gain. Furthermore, barley silage produced the least fat cover and lowest dressing percent. Performance of steers fed dry-ground barley was intermediate during the first year, but comparable with performance on corn silage in gain and carcass measurements during the second trial. Digestible energy intake tended to be highest for steers fed corn silage. Sheep were used to determine digestibilities of forages fed in the feedlot studies, and of whole-plant barley at various stages of maturity. Corn silage had the highest energy digestibility of all forages studied. Energy digestibility of whole-plant barley decreased slightly to the milk stage but did not change thereafter. After the milk stage, the barley had a moisture content below 70%, thus enabling direct harvesting for silage.
EFFECT OF THYROPROTEIN ON PERFORMANCE OF DWARF LAYERS
Authors: RAJARATNAM G. , SUMMERS J. D. , MORAN Jr. E. T. , WOOD A. S.
Published: March 2010

A study was undertaken to investigate the laying performance of dwarf pullets, under the influence of varying levels of Protamone (trade name of thyroprotein, contains 1% thyroxine activity) in the diet. No significant difference in metabolizable energy values was observed between dwarf and non-dwarf layers. The overall reproductive performance was significantly lower for dwarfs than for non-dwarfs. Protamone feeding had no significant effect in improvement of metabolic or reproductive efficiency of dwarf hens.
LTVER ABSCESSES IN INTENSIVELY REARED HOLSTEIN-FRIESIAN STEERS
Authors: Lister E. E.
Published: March 2010

not available
FEEDING VALUE OF POPLAR SILAGE IN RATIONS FOR YEARLING STEERS
Authors: Robertson J. A. , Beacom S. E. , Shield R.
Published: March 2010

not available
A TEAT BAR FOR GROUP FEEDING COLD LIQUID DIETS TO LAMBS
Authors: Gorrill A. D. L. , Veerkamp A. J. , MacIntyre T. M.
Published: March 2010

not available
CHARACTERISTICS OF YOUTHFUL BEEF CARCASSES IN RELATION TO WEIGHT, AGE AND SEX: I. ORGAN WEIGHTS, SLAUGHTER LOSS AND COOLER SHRINK IN PRODUCTION OF THE DRESSED CARCASS
Authors: FREDEEN H. T. , MARTIN A. H. , WEISS G. M.
Published: March 2010

In a study of youthful slaughter cattle comprising 168 steers, 147 heifers and 259 bulls, minor but statistically significant (P < 0.05) sex differences were observed for percent hide, shanks and head (steers > bulls > heifers) and percent kidney and cod or udder fat (heifers > bulls > steers). Bulls dressed approximately 1% higher and heifers 1% lower than steers, these sex differences apparently arising from items not recorded on the killing floor (including blood, lungs, digestive tract and contents and reproductive tract of females). Sex differences, particularly the bull versus steer comparisons, may have been influenced by differences in breed and/or pre-test treatment. Percentage internal fat trim and unrecorded slaughter loss were positively, and percent head, hide, shanks and internal organs negatively, correlated with liveweight at slaughter. However, slaughter weight accounted for less than 5% of the variance in dressing percentage, and age independent of slaughter weight had little influence on any of the traits studied. Total recorded slaughter loss expressed as a proportion of carcass weight decreased 0.1 to 0.4% per 100 kg increase in slaughter weight. The importance of pre-slaughter shrink in determining total slaughter loss was discussed.
DISSOLUTION OF SILICA FROM DRIED GRASS IN NYLON BAGS PLACED IN THE RUMEN OF A COW
Authors: BLACKMAN ELIZABETH , BAILEY C. B.
Published: March 2010

Samples of dried green (5.8% silica) and weathered (9.4% silica) rough fescue grass (Festuca scabrella Torr.) were placed in nylon bags and subjected to digestion in the rumen of a fistulated cow for up to 24 hr, and then analyzed for silica. The diet of the cow was either prairie hay, which saturated the rumen fluid with silica, or alfalfa hay, which did not. More silica dissolved from the samples when the cow was fed alfalfa hay than when fed prairie hay. The absolute and the proportionate amounts of silica that dissolved from weathered grass were greater than those dissolved from green grass, in the presence both of alfalfa hay and prairie hay. Silica that had dissolved in saliva squeezed from swallowed hay was about 1% of the total silica in the hay. The experimental results and microscopic observations indicate that silica in grass is composed of fractions with different tendencies to dissolve during digestion.
CONVERSION OF BODY FAT AND PROTEIN TO ENERGY AND THE TRANSFER OF CARBON FROM FATTY ACIDS TO GLUCOSE IN THE GROWING PIG
Authors: CUNNINGHAM H. M.
Published: March 2010

The amount of body fat used for energy at various times of the day by pigs was determined by continuous sampling of expired air from fasting pigs whose body fat was labeled with14C-palmitic acid. After 3 to 6 hr of fasting, the level of expired14CO2per hr was 13% of that expired after 48 to 72 hr of fasting, and the average level during the first 12 hr of fasting was 18%. Calculations based on the14C activity of lipids and proteins in the blood and tissues of the pigs indicated that, during the first 12 hr of fasting, approximately one-eighth of the energy utilized was derived from body fat and protein. It also appeared that the fasting pig is capable of incorporating carbon into blood glucose from fatty acids of either endogenous or exogenous origin.
TRANSMISSION OF SELENIUM AS SELENITE AND AS SELENOMETHIONINE FROM EWE TO LAMB VIA MILK USING SELENIUM-75
Authors: JENKINS K. J. , HIDIROGLOU M.
Published: March 2010

Selenite and selenomethionine, both labeled with75Se and administered via the feed to lactating ewes, were compared as sources of selenium for suckling lambs. During a 2-week post-partum period,75Se levels in ewe blood serum and milk increased at a much higher rate when the ewe received selenite. For selenite administration, the colostrum caseins (β and γ), which contained low levels of cystine, had relatively low75Se specific activities; the β lactoglobulin and α lactalbumin proteins, which contained high levels of cystine, had high75Se concentrations. The radioselenium apparently was complexed as selenotrisulfide. For the selenomethionine treatment, radioselenium was incorporated to the greatest extent in the milk proteins which had the highest level of either methionine or total content of sulfur amino acids. In post-colostrum milk, most of the milk75Se activity (73–79%) was carried by the caseins regardless of maternal selenium treatment.75Se concentrations were appreciably higher in the serum proteins and tissues of the lamb whose dam received selenomethionine. The data indicate that the ewe made better use of selenite than selenomethionine for secreting higher levels of selenium in the milk. However, when the ewe was fed selenomethionine, the forms of selenium in the milk were more available to the pre-ruminant lamb.
DIGESTIBLE AND METABOLIZABLE ENERGY VALUES FOR RAPESEED MEALS AND FOR SOYBEAN MEAL FED TO GROWING PIGS
Authors: SABEN H. S. , BOWLAND J. P. , HARDIN R. T.
Published: March 2010

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. There were no significant differences in DE, ME or MEn among the 12 RM samples, or between weight periods. The values for the basal diet were uniform throughout. The overall mean coefficient for DN was 75.9% for RM and 89.2% for SM. The DE, ME and MEn values for RM should be considered as being species specific.
EFFECTS OF ALKALI TREATMENT AND GAMMA IRRADIATION ON THE CHEMICAL COMPOSITION ANDIN VITRORUMEN DIGESTIBILITY OF CERTAIN SPECIES OF WOOD
Authors: HUFFMAN J. G. , KITTS W. D. , KRISHNAMURTI C. R.
Published: March 2010

Changes in the chemical composition and in vitro rumen digestibility of alder, fir, poplar and sludge were studied after treatment with NaOH and gamma irradiation. Treatment with alkali increased the percentage of cellulose and acid detergent fiber (ADF) in all species of wood studied, whereas the average acid detergent lignin (ADL) content was not affected. Alkali treatment increased the in vitro dry matter disappearance (DMD) of alder and poplar, and increased the in vitro cellulose digestion of alder, poplar and sludge. Samples of the four species of wood that were exposed to 1 × 108or 2 × 108rads of gamma irradiation were lower in cellulose, ADF and ADL content than the untreated samples, or those exposed to 1 × 106or 1 × 107rads. In vitro DMD, cellulose digestion and volatile fatty acid production were higher in samples of all four species exposed to 1 × 108or 2 × 108rads, than in untreated samples, or in those exposed to 1 × 106or 1 × 107rads.
MASS SELECTION FOR POST-WEANING GROWTH IN SWINE: I. THE VALUE OF A PEDIGREED CONTROL POPULATION
Authors: RAHNEFELD G. W.
Published: March 2010

A pedigreed control population of Yorkshire swine has been described. The average size of the breeding population was 20 males and 40 females in each of the seven generations. The effective number of parents per generation was estimated at 87.5. There has been little or no evidence of any significant changes in the genetic value of the population over the seven generations as determined by estimates of additive genetic variance, selection differentials, and other related parameters. The performance of the control population was compared with that of a selected population and with crossbreds produced by mating select population males to control population females. Comparisons were made in the same environments. The comparisons of the effects of the selection program on several traits measured in the two populations have been made, based on the absolute trends in these populations over the seven generations and as a deviation from the performance of the control population.
FAT DISTRIBUTION IN SWINE AS INFLUENCED BY LIVEWEIGHT, BREED, SEX AND RATION
Authors: RICHMOND R. J. , BERG R. T.
Published: March 2010

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%. Within each depot type, differential deposition between front and hind quarters was most noticeable between 23 and 68 kg liveweight. During this period, more of the intermuscular and body cavity fat was deposited in the front quarter, while a greater proportion of the subcutaneous fat was deposited in the hind quarter. Breed, sex and ration did not influence the percentage relationship among depot fat types but did within types. Thus, the fatter carcasses (produced by Duroc × Yorkshire pigs, barrows and high-energy-fed pigs) had a greater proportion of their intermuscular fat in the hind quarter than did the leaner carcasses (from Hampshire × Yorkshire and Yorkshire × Yorkshire pigs, gilts and pigs fed the low energy ration).
INFLUENCE OF SELENIUM ON THE TIME DISTRIBUTION OF TRITIUM-LABELLED TOCOPHEROL IN SELECTED TISSUES OF THE RAT
Authors: Cheeke P. R. , Oldfield J. E.
Published: March 2010

not available
SERUM ASCORBATE LEVELS IN SWINE WITH CARDIAC MUSCULAR DYSTROPHY (MULBERRY HEART DISEASE) AND HEPATOSIS DIETETICA
Authors: Brown R. G. , Sharp B. A. , Young L. G. , Drcuracl A. Van
Published: March 2010

not available
SUBCUTANEOUS AND ORAL APPLICATIONS OF PROGESTAGENS FOR CONTROL OF ESTRUS IN HEIFERS
Authors: Scanlon P. F. , Burgess T. D.
Published: March 2010

not available
AN IN VIVO METHOD FOR ASSESSING THE DEGRADATION OF NITROGENOUS COMPOUNDS IN THE RUMEN
Authors: Atwal A. S. , Young B. A. , Milligan L. P.
Published: March 2010

not available
BLOOD SAMPLING FROM SUCKLING PIGLETS
Authors: Friend D. W. , Brown R. G.
Published: March 2010

not available
INFLUENCE OF COW SIZE AND OTHER FACTORS ON WEIGHT GAIN OF BEEF CALVES TO 365 DAYS OF AGE
Authors: JEFFERY H. B. , BERG R. T.
Published: March 2010

A study involving three sets of data from the University of Alberta beef breeding herd (1966–67, 176 cows; 1967–68, 167 cows; 1968–70, 285 cows) was conducted to determine the influence of birth weight of calf (BW), postcalving weight of dam (PCW), and breed effect on calf performance to 365 days of age. The influence of preweaning on postweaning performance was also considered. Calves heavier at birth tended to excel in both preweaning and postweaning growth rate. A 1-kg increase in BW resulted in an increase of 2.86–4.42 kg in calf weight at 365 days of age. For male calves, PCW was negatively associated with calf weight at both 180 and 365 days of age for 1966–67 data; however, for 1967–68 and 1968–70 data, a 10-kg increase in PCW resulted in 0.70- and 0.92-kg increases, respectively, in calf weight at 180 days, and 1.96- and 2.12-kg increases in calf weight at 365 days, respectively. For female calves, a 10-kg increase in PCW resulted in 1.40-, 0.88-, and 0.29-kg increases in calf weight at 180 days of age, and 0.68-, 1.31-, and 0.31-kg increases in calf weight at 365 days of age, respectively, for the three sets of data. Breed difference explained from 22 to 43% of the variance in average daily gain of calf to weaning (ADG) but only 0.2–13.8% of the variance in postweaning average daily gain (PWADG). Male calves with higher ADG to weaning or heavier weaning weights tended to have slightly higher PWADG. A 10-kg advantage in weaning weight for male calves resulted in a 12–14-kg advantage in weight at 365 days of age.
INFLUENCE OF CARBON DIOXIDE ABSORBENT AND PERCENTAGE ATMOSPHERIC CARBON DIOXIDE ON OXYGEN UPTAKE BY BOAR SPERMATOZOA
Authors: SANFORD L. M. , KING G. J.
Published: March 2010

Boar spermatozoa were diluted in Ringer’s fructose or sulfate buffer and incubated aerobically for 4 hr at 37 C (a) in the presence of potassium hydroxide (KOH), hyamine hydroxide, or diethanolamine (DEA) absorbents, and (b) in 1, 2, or 3% atmospheric levels of carbon dioxide. Oxygen uptake by boar spermatozoa was enhanced by the presence of DEA compared with KOH and hyamine hydroxide. Incubation with DEA resulted in increased spermatozoan livability, more desirable cell motion, and smaller increases in buffer pH. Oxygen uptake by boar spermatozoa was optimum with 1 or 2% carbon dioxide, depending upon which buffer cells were diluted in. Levels of 2 and 3% carbon dioxide maintained oxygen uptake and livability of boar spermatozoa during later stages of the incubation period equally as well as 1% carbon dioxide. As the level of atmospheric carbon dioxide increased, buffer pH remained closer to the initial value.
INFLUENCE OF GLYCEROL CONCENTRATION AND FREEZING TO −79 C ON OXYGEN UPTAKE AND LIVABILITY OF BOAR AND BULL SPERMATOZOA
Authors: SANFORD L. M. , KING G. J. , MACPHERSON J. W.
Published: March 2010

Boar and bull spermatozoa were diluted in a skim milk–egg yolk–glucose extender containing 0, 7.5, or 15% glycerol (v/v) and incubated aerobically for 6 hr at 37 C. Other partially diluted boar semen samples were cooled to 5 C. Glycerol was added to a final concentration of 0, 7.5, and 15%. Samples were frozen to −79 C, rewarmed, and incubated for 3 hr at 37 C. The presence of glycerol in the extender depressed (P < 0.01) the oxygen uptake by nonfrozen boar and bull spermatozoa during the 6-hr incubation period. The reduction of oxygen uptake by semen samples increased as the level of glycerol in the extender increased. There was a corresponding decrease (P < 0.01) in the number of motile cells at the conclusion of the incubation period. Glycerol appeared to have more of a detrimental effect on boar spermatozoan oxygen uptake. The rate of oxygen uptake by boar semen samples postfreezing was extremely depressed, suggesting that spermatozoa surviving the freezing process metabolize at a much lower rate than normal. Active progressive motility of most of the surviving boar spermatozoa ceased within 1–2 hr of incubation under the in vitro conditions of this experiment.
FEEDING VALUE FOR BEEF AND DAIRY CATTLE OF HIGH MOISTURE CORN PRESERVED WITH PROPIONIC ACID
Authors: FORSYTH J. G. , MOWAT D. N. , STONE J. B.
Published: March 2010

Two trials with growing-finishing steers and one trial with lactating dairy cows were conducted to evaluate the feeding value of high moisture (HM) corn preserved with 1.5% propionic acid on a wet weight basis. Combining all treatments, acid-treated HM corn was 9% more efficient (P < 0.05) for weight gains than dry corn. Ensiled HM corn also tended to be utilized more efficiently by steers than dry corn when no fat was included in the ration. However, in the second steer trial, acid-treated reconstituted HM corn was comparable in performance with dry corn. Addition of 4% tallow tended to improve feed efficiency by 5–6% with dry or acid-treated HM corn, but to decrease feed efficiency with ensiled HM corn. No significant differences were observed in forage dry matter intake, milk production, or milk composition with cows fed treated HM corn compared with dry corn. However, a trend for a slight reduction in milk fat percent occurred with the treated corn ration.
RESPONSE OF MALE AND FEMALE WEANLING RATS TO DIETS OF DIFFERENT DIGESTIBLE ENERGY CONCENTRATIONS AND TO SUPPLEMENTATION WITH VITAMIN E, USING BARLEY OR WHEAT AS CEREAL SOURCES
Authors: O’GRADY J. F. , BOWLAND J. P.
Published: March 2010

Sixty-four weanling rats were used in an experiment lasting 6 weeks to test the response of male and female rats to diets having 2.8, 3.0, 3.2, and 3.4 Mcal digestible energy (DE) per kg, where barley and wheat were used as the cereal sources and diets were supplemented with 22 IU vitamin E/kg or unsupplemented. The use of wheat or barley did not influence the performance of female rats but males utilized barley-based diets better than wheat diets and gained more in some weeks, though not overall. Male rats did not respond to vitamin E supplementation but females consumed more of the vitamin E-supplemented diets and grew 6% faster (P < 0.10). Except in the 1st week, females ate more of the lower energy than of the higher energy diets and so DE concentration did not influence rate of gain. Males were not able to adjust food intakes to compensate for dietary energy levels and needed a DE concentration of 3.2 Mcal/kg diet for maximum growth. The data indicate that there is a sex difference in growing rats insofar as DE concentration of the diet required for maximum gain is concerned.
EFFECTS OF POPULATION DENSITY ON ENERGY UTILIZATION, INTESTINAL DISACCHARIDASES, AND ADRENAL FUNCTION IN HENS
Authors: LEI K. Y. , STEFANOVIC M. P. , SLINGER S. J.
Published: March 2010

Two experiments were carried out with laying hens to determine the effect of overcrowding stress on reproductive performance and on certain other parameters that might be expected to be affected and thus be useful indices of this type of stress. The first experiment consisted of eight treatments in a factorial arrangement with four bird densities of one, two, three, or four birds in 30.5 × 45.7-cm (12 × 18″) cages and two levels of dietary energy. The second experiment involved three bird densities of one, three, and five birds in 30.5 × 45.7-cm cages fed a single diet. There were four replicate cages per treatment in both experiments. Feed consumption, weight gain, and egg production were not significantly affected by the population densities employed in experiment 1. In experiment 2, increasing bird density significantly reduced egg production, and hens maintained at five per cage suffered a net loss of body weight. In neither experiment was energy utilization affected by crowding since the dietary metabolizable energy values remained constant. In both experiments mucosal maltase and sucrase activities were significantly increased with increasing bird density when birds were fed diets of relatively normal starch content. Plasma-free fatty acids, total fatty acids, and triglyceride levels were not significantly affected by population density, nor were the oleic–linoleic–arachidonic acid levels expressed as percentages of total fatty acids. It would thus appear that lipid metabolism remained relatively normal in hens subjected to overcrowding stress. The levels of peripheral plasma corticosterone and adrenal corticosterone increased in a linear fashion in both experiments with increasing bird density. It would appear that plasma and adrenal corticosterone levels might be useful indices of overcrowding stress in hens.
SIMPLIFICATION OF HIGH WHEAT DIETS FOR LAYING HENS: VALUE OF SUPPLEMENTATION WITH METHIONINE HYDROXY ANALOGUE
Authors: SLINGER S. J. , PEPPER W. F. , SUMMERS J. D.
Published: March 2010

Groups of laying strain pullets were maintained singly in wire cages and fed a diet in which rolled, feed grade, hard red spring wheat was the sole cereal grain and no protein supplement was added. For other groups this diet was supplemented with 5, 10, or 15% soybean meal, or 2% blood meal. A further treatment consisted of replacing 10% wheat with soybean meal and using one-half wheat and one-half corn as the cereal portion of the diet. All of the above diets were fed in the absence of amino acid supplementation and in the presence of methionine hydroxy analogue (MHA). The duration of the experiment was eight periods of 28 days. The results suggested that with a simplified diet based on wheat and soybean meal, between 10 and 15% soybean meal was necessary for optimum reproductive performance. The supplement of MHA improved performance only in diets where total protein or lysine, or both, was/were not first limiting. The simplified diet containing 87.25% wheat, 2% blood meal, and 0.125% MHA supported a rate of egg production of 68%, clearly demonstrating the extent to which wheat might be used with further slight modifications of the diet.
EFFECTS OF HEAT TREATMENT ON THE NUTRITIVE VALUE OF WHOLE RAPESEED FOR POULTRY
Authors: WOODLY A. , BILANSKI W. K. , SUMMERS J. D.
Published: March 2010

Three experiments were conducted to investigate the nutritive value of full-fat rapeseed when subjected to heating temperatures ranging from 232 to 427 C for periods of from 1 min to 5 sec. Chicks either 1 day or 1 week old were fed diets containing treated rapeseed, and weight gain, feed:gain ratio, and thyroid weights were recorded. Although there was variability in response to the test diets, depending on treatment temperature and length of treatment time, the data indicate a marked improvement in nutritive value of full-fat rapeseed with proper processing conditions. Evidently a relatively wide range of temperature–time combinations could be used to obtain the optimum processing treatment. The study indicated that the test diets were not palatable to chicks at 1 day of age; however, when fed over a 4-week period, the birds overcame the slow start and were as heavy as those fed a control diet in which the protein was supplied by soybean meal.
INTRAUTERINE MIGRATION AND MORTALITY OF SHEEP EMBRYOS
Authors: SITTMANN K.
Published: March 2010

not available
FEEDLOT AND CARCASS PERFORMANCE OF YOUNG BULLS REPRESENTING SEVERAL BREEDS AND BREED CROSSES
Authors: FREDEEN H. T. , MARTIN A. H. , WEISS G. M. , SLEN S. B. , SUMPTION L. J.
Published: March 2010

A population of 174 hybrid bulls was used to evaluate pre- and postweaning growth and carcass characteristics of crosses involving Angus, Hereford, and Holstein dams and Angus, Hereford, Brown Swiss, Charolais, and Shorthorn sires. Progeny of Holstein dams excelled (P < 0.01) for pre- and postweaning growth traits. Breed of sire differences were generally nonsignificant except for growth rate in the feedlot. Dressing percentage was not influenced by breed of dam or sire. Hide weight was least for progeny of Holstein dams and greatest for progeny of Hereford dams and sires (P < 0.01). Holstein and Brown Swiss crosses had a higher proportion of bone (P < 0.01), a greater proportion of chuck and round, and a lower proportion of rib and sirloin than crosses from the British breeds. Area of rib eye was influenced by breed of dam but not breed of sire. British breed crosses had the greatest and Holstein, Brown Swiss, and Charolais crosses the least rib fat (P < 0.01). Total deboned–defatted lean yield of the carcass was least for the British breed crosses. Breed crosses did not differ in ether extract values from the longissimus dorsi but British breed crosses showed the greatest degree of marbling. No breed of sire or breed of dam differences were detected in tenderness of the longissimus dorsi, either by Warner-Bratzler or taste-panel evaluation, but significant breed of sire–breed of dam interactions were evident for these traits. Progeny of Hereford dams were more efficient (P < 0.01) than progeny of Holstein dams in converting feed to liveweight gain. This tended to negate the Holstein-cross advantage in growth rate and lean content, and there were no breed of dam differences in energy requirements per unit of lean produced. For the breed of sire comparisons, calves from the British breeds required the greatest energy intake per unit of lean product (P < 0.05).
EFFECTS OF COLD STRESS AND REPEAT MATING ON REPRODUCTIVE PERFORMANCE OF SWINE
Authors: SWIERSTRA E. E. , RAHNEFELD G. W.
Published: March 2010

The effects of cold stress, as measured by minimum ambient temperatures at day(s) of mating, on conception rate (CR), and litter size were studied in purebred Yorkshire and Lacombe swine populations maintained at the Canada Agriculture Research Station, Brandon, Manitoba (49°50′N, 99°57′W). One hundred and sixty-nine Yorkshire and 160 Lacombe boars were used to hand mate 406 Yorkshire gilts (505 estruses) and 460 Lacombe gilts (558 estruses). All gilts were bred on the 1st day of standing estrus, and gilts still in estrus the next day were mated a second time with the same boar. All matings were carried out in December and January over an 8-year period. Gilts and boars were housed separately in outside pens with wooden cabins as shelter. The data were grouped on the basis of minimum temperature on day(s) of mating into the following arbitrarily chosen temperature ranges: < −25, −25 to −18, −17 to −10 and > −10 C. The CR for gilts mated once were 81, 73, 58, and 56%, respectively, for the four temperature ranges. Corresponding values for the gilts mated more than once were 88, 81, 73, and 65%. Chi-square analyses indicated that CR were dependent (P < 0.01) on ambient temperatures. Repeat mating per estrus increased CR of the Yorkshire gilts by 12.5% (77.9 vs. 65.4%) and of the Lacombe gilts by 11.3% (80.4 vs. 69.1%) as compared with single mating. In both breeds, repeat mating increased litter size by 0.3 piglets (9.2 vs. 8.9, P = 0.10) over single matings. Litter size was not influenced by cold stress at time of mating.
EFFECTS OF VITAMIN E OR ETHOXYQUIN AND RUMEN DEVELOPMENT UPON MUSCULAR DYSTROPHY IN LAMBS
Authors: deMILLE F. , BUCHANAN-SMITH J. G. , MILLER R. B.
Published: March 2010

In a 2 × 3 factorial procedure, torula yeast-lard (10%) diets supplemented with either vitamin E (68 IU/kg) or ethoxyquin (0.01 or 0.1%) were fed to 27 1-week-old crossbred lambs to promote or prevent rumen development. After a 12-week trial period, myopathy was apparent in 100, 25, and 0% of lambs fed diets supplemented with ethoxyquin (0.01, 0.1%) or vitamin E, respectively. Seven lambs died prematurely but only one of these deaths was attributed to myopathy. Rumen development did not affect the occurrence of myopathy but reduced (P < 0.05) the elevation of plasma glutamate-oxaloacetate transaminase (GOT) in myopathic lambs during the trial. Vitamin E improved (P < 0.05) average daily gain of lambs (mean 142.0 g) compared with 0.01% ethoxyquin (0.1% ethoxyquin intermediate) and rumen development had no apparent effect. Tissue ethoxyquin levels reflected amounts fed and were unaffected by rumen development. Rumen development generally reduced the content of polyunsaturated fatty acids in muscle phospholipids and adipose tissue, whereas vitamin E or ethoxyquin specifically affected linoleic acid.
NUTRITIVE VALUE OF FORMALDEHYDE-TREATED RAPESEED MEAL FOR DAIRY CALVES
Authors: SHARMA H. R. , INGALLS J. R. , McKIRDY J. A.
Published: March 2010

Treatment of oilseed meals with formaldehyde (FA) and glutaraldehyde (GA) significantly (P < 0.01) reduced the solubility of protein in 0.02 N NaOH and the production of NH3 in the artificial rumen. Ten Holstein and Holstein × Brown Swiss calves of both sexes were fed two test rations containing either 26% untreated or formaldehyde-treated (5.6 g FA per 100 g protein) rapeseed meal (FA-treated RSM) for 14 weeks. Plasma urea nitrogen (N) and rumen NH3 levels were significantly (P < 0.01) lower in the FA-treated RSM calves compared with the control calves during the first 8 weeks of the growth trial. No significant difference (P > 0.05) in dry matter consumption, daily gain, or feed efficiency was observed. Total volatile fatty acids (VFA) (mmoles/100 ml) concentration was significantly higher (P < 0.05) in rumen fluid from the control calves compared with those receiving treated RSM. Molar percentages of the VFA’s were not significantly different (P > 0.05) between the two groups. In the N balance and digestibility trial, dry matter consumption did not differ significantly (P > 0.05); however, the FA-treated RSM resulted in decreased (P < 0.05) dry matter and crude protein digestibility. Calves receiving the treated RSM had reduced (P < 0.01) urinary N excretion; however, there was no significant effect (P > 0.05) on N consumption and retention.
RESPONSE OF LACTATING COWS TO THE INTRAVENOUS INFUSION OF AMINO ACIDS
Authors: FISHER L. J.
Published: March 2010

High, low, and zero quantities of methionine, histidine, or lysine were infused intravenously into lactating cows fed a corn–corn silage–urea ration to assess whether any of these amino acids were limiting for milk production. Feed intake was significantly higher (P < 0.05) with the low level of methionine infusion than with either the high level or saline infusions. Milk yield was not affected (P > 0.05) by any treatments, but protein yield was significantly greater (P < 0.05) with the low than with the high or zero levels of infusion of methionine, and the infusion of either level of histidine significantly decreased (P < 0.05) milk protein yield compared with zero level of infusion. The changes in levels of plasma amino acids that occurred during these studies have been interpreted as implying that methionine was the first limiting and either valine, leucine, or isoleucine was the second limiting amino acid for milk production.
HISTOPATHOLOGY OF THYROIDS AND LIVERS OF RATS AND MICE FED DIETS CONTAINING BRASSICA GLUCOSINOLATES
Authors: BELL J. M. , BENJAMIN B. R. , GIOVANNETTI P. M.
Published: March 2010

A histopathological comparison was made of thyroid and liver tissue from weanling mice and rats fed six different diets. The experimental diets contained mustard or rapeseed meal (RSM) varieties of high glucosinolate content, namely, Oriental mustard (Brassica juncea), Yellow Sarson (B. campestris), Target (B. napus) and Fe-treated Target (glucosinolate hydrolyzed by FeSO4). The two control diets contained a low glucosinolate variety of rapeseed meal, Bronowski (B. napus), or casein to provide approximately 20% dietary protein. Seven mice and seven rats were fed each diet 4 and 6 weeks, respectively. Both body growth rate and the histopathology of the thyroid gland were affected by the inclusion of rapeseed meals in the diet. The effect was more marked in rats than in mice. Whereas the high glucosinolate-containing RSM (cult Target) diet produced poorest performance in rats (P < 0.01) and mice (P < 0.05), the low glucosinolate RSM (cult Bronowski) diet was as efficiently utilized as the casein diet. Epithelial cell heights of the thyroid follicles were increased in the mice and rats fed Target RSM, but only rats showed a high degree of papillary formation. Liver involvement at the microscopic level was slight. The measurement of epithelial cell height showed most promise as an accurate indicator of cell size.
MOIST HEATING OF SOYBEANS FOR PIGS FED DIETS BASED ON CORN
Authors: YOUNG L. G.
Published: March 2010

Two growth trials involving a total of 36 individually fed Yorkshire gilts were conducted to compare the value of supplemental protein from soybean meal, raw soybeans, and cooked soybeans for growing pigs. Three metabolism trials were also conducted. Cooked soybeans were prepared by cooking in water for approximately 6 hr. The protein supplements were fed at a level calculated to supply the same amount of supplemental protein daily. Performance of pigs fed soybean meal or cooked soybeans was similar and superior to that of pigs fed raw soybeans as indicated by rate of gain, feed intake, and gain to feed ratio. The higher gross energy of cooked soybeans or raw soybeans did not result in increased digestible or metabolizable energy content of the diet. Protein digestibility and retention was lower for diets containing raw soybeans.
EFFECTS OF VARIABLE INCUBATING TEMPERATURES, NUMBER, AND PROXIMITY OF EGGS DURING HATCHING ON THE HATCHABILITY OF CHICKEN EGGS
Authors: PROUDFOOT F. G.
Published: March 2010

An experiment involving 5760 eggs was conducted to evaluate the effect on hatchability of periodic reductions in incubation temperatures caused by setting two-sevenths of the incubator capacity weekly, using "cold" (11 C) eggs vs. "prewarmed" (37 C) eggs. No overall detrimental effect could be demonstrated despite a temporary 5 degrees C reduction in incubator air temperature. Three other experiments, involving 4080 embryonated eggs in Jamesway 252 incubators, were designed to evaluate the effect of (1) the number of eggs per hatching tray and (2) the closeness of eggs during hatching on hatchability. Although egg numbers varied from 30 to 150 eggs per tray, there was no evidence that either the number of eggs per tray or separation vs. contact between eggs during hatching had any effect on hatchability.
WHOLE CROP BARLEY AS CONSERVED FORAGE FOR LACTATING COWS
Authors: FISHER L. J. , LESSARD J. R. , LODGE G. A.
Published: March 2010

Whole crop barley harvested as hay at the milk stage and at three stages of maturity as silage was fed to each of 16 lactating cows, over successive periods of 49 days each, according to a simple changeover design. The barley hay and barley silages contained 86.2, 26.1, 33.4, and 47.9% dry matter (DM), 14.2, 12.5, 11.1, and 9.2% crude protein, and 31.1, 34.1, 29.2, and 28.0% crude fiber for the hay, milk, soft dough, and firm dough stages of maturity, respectively. Forage DM intake was significantly lower (P < 0.05) for hay than for any of the silages and for the milk stage silage than for the more mature silages. There were no significant effects of diet on milk yield, but milk protein content was significantly lower (P < 0.05) and lactose content significantly higher (P < 0.05) when milk stage silage was fed compared with hay or the other silages. The ratio of acetate to propionate in the rumen fluid was significantly greater (P < 0.05) for cows fed hay than when fed silage. The apparent digestibilities of forage DM were 59.2, 59.4, 59.0, and 55.9% and the efficiencies of digestible energy utilization of complete rations corrected for body weight change were 49.1, 43.9, 42.2, and 42.3% for barley hay, and silages at the milk, soft dough, and firm dough stages of maturity, respectively.
EFFECTS OF BARLEY AND WHEAT CULTIVARS ON GROWTH OF THE CHICK
Authors: STRAIN J. H. , PILOSKI A. P.
Published: March 2010

Five barley (Hordeum sp.) and three wheat (Triticum aestivum L. em Thell.) cultivars, each supplemented with minerals and vitamins, were fed to White Leghorn cockerel chicks. Differences due to barley cultivars were significant for shank length but not for average daily gain, although the ranking was identical for both traits (r = 0.997). No large differences were found between the wheat cultivars. Body weight at 10 weeks, feed efficiency, and mortality were not affected by cultivar.
EFFECTS OF ERGOT ON REPRODUCTIVE PERFORMANCE IN MICE AND GILTS
Authors: CAMPBELL C. W. , BURFENING P. J.
Published: March 2010

not available
INFLUENCE OF BOVINE SALIVA ON GRASS REGROWTH IN THE GREENHOUSE
Authors: JOHNSTON A. , BAILEY C. B.
Published: March 2010

not available
A REVIEW OF SELENIUM/VITAMIN E RESPONSIVE PROBLEMS IN LIVESTOCK: A CASE FOR SELENIUM AS A FEED ADDITIVE IN CANADA
Authors: JENKINS K. J. , HIDIROGLOU M.
Published: March 2010

It has been amply demonstrated by scientific experimentation that selenium (Se) and vitamin E are essential micronutrients required for the good health of animals throughout their life cycle and for the attainment of high levels of production. In Canada there is widespread occurrence of Se/vitamin E responsive diseases in livestock, causing substantial financial losses to animal producers. As the Se and vitamin E contents of feed ingredients and their effective availabilities vary widely, a continuous supply of an active form of these micronutrients to farm animals is required. Published data suggest that for prepared swine and chicken diets there is a need for supplementation with at least 0.1 ppm Se (from sodium selenate or selenite) and 10 ppm α-tocopheryl acetate. Turkeys appear to require dietary additions of 0.2 ppm Se and 10 ppm vitamin E. For beef cattle and sheep, either on the range or in confinement, "selenized" salt, mineral mixes, or mineral blocks appear at this time to be the preferred method for providing additional Se. Presently available data indicate that 26 ppm Se is an effective level in salt mixes for prevention of muscular dystrophy. It was estimated from recent published data on the Se content of Canadian food items that the provision of Se supplements to livestock, as described, would have a negligible influence on the average daily intake of Se by the Canadian public, thereby precluding controversy over any beneficial or detrimental role of the element in humans. The amount of Se that would be recycled through the animal excreta–soil–plant–human food chain was exceedingly small.
SOME EFFECTS OF METHANE INHIBITION IN RUMINANTS (STEERS)
Authors: JOHNSON E. D. , WOOD A. S. , STONE J. B. , MORAN JR. E. T.
Published: March 2010

Four steers were used in a 4 × 4 latin square experiment to assess comparative antimethanogenic effects of including bromochloromethane (BCM) (5.5 g once daily), unsaturated fat (corn oil), and saturated fat (tallow) at 5% in experimental diets. Basic dietary ingredients were citrus pulp and beet pulp plus hay. Average daily gain (ADG) and ruminal parameters including soluble carbohydrate and total volatile fatty acid (TVFA) concentrations, VFA’s percentages, and pH were measured. Only BCM proved significantly (P < 0.05) antimethanogenic. Maximal inhibition occurred 0–6 hr post-feeding, by 15 hr inhibition was reduced by 50% and absent at 24 hr. Ruminal TVFA, pH, and average daily gain were not significantly affected (P > 0.05) by CH4 inhibition, although average daily gain showed the following trend: BCM > saturated fat > unsaturated fat > control. Inhibition caused lower (P < 0.05) ruminal acetate, and higher (P < 0.05) propionate over 24 hr post-feeding, higher (P < 0.05) butyrate from 3–15 hr post-feeding, and consistent measurable quantities of valerate and isovalerate. Soluble CHO concentration was maximal 0–6 hr post-feeding.
NITROGEN BALANCE AND PLASMA-FREE FATTY ACID LEVELS OF GILTS DURING ESTRUS AND DIESTRUS
Authors: FRIEND D. W. , CUNNINGHAM H. M.
Published: March 2010

Twelve Yorkshire gilts were used in metabolism trials to determine the effects of estrus on nitrogen balance and plasma-free fatty acid (FFA) levels. Five 24-hr feces and urine collections were taken during each of the estrus and diestrus periods of one or two reproductive cycles. Samples of ear vein blood were collected on each of the 5 days. The mean 5-day values for N retention were 48 ± 22 and 47 ± 20 g per 100 g N intake for estrus and diestrus, respectively. Results indicated, therefore, that the effect of estrus on N balance is such that a comparison between pregnant and nonpregnant pigs need not take into account the occurrence of estrus. Levels of FFA during estrus and diestrus were 121 ± 63 and 110 ± 64 μeq per liter, these effects being associated with significant (P < 0.01) interaction effects within the nested classification.
CONTROL OF ESTRUS IN BEEF CATTLE BY ORAL APPLICATION OF MEGESTROL ACETATE
Authors: SCANLON P. F. , BURGESS T. D.
Published: March 2010

not available
THE HEAT OF COMBUSTION VALUES OF THE PROTEIN AND FAT IN THE EMPTY BODIES OF YOUNG PIGS
Authors: SHARMA V. D. , YOUNG L. G. , SMITH G. C.
Published: March 2010

not available
EFFECTS OF FOUR LIGHTING REGIMES ON THE PERFORMANCE OF BROILERS AND ROASTERS
Authors: BUCKLAND R. B. , HILL A. T. , BERNON D. E.
Published: March 2010

The effects of the following light treatments on 8-wk broiler and 14-wk roaster performances were compared: (1) continuous light; (2) an intermittent system of 1 h light and 3 h darkness during the night, with 13 h continuous light of the same intensity during the day; (3) an intermittent sytsem of 1 h light and 3 h darkness during the full 24-h period; (4) an intermittent system of 1 h light and 1 h darkness from 1 to 2 wk of age, 1 h light and 2 h darkness from 2 to 3 wk of age, and 1 h light and 3 h darkness from 3 to 14 wk of age during the full 24-h period. All birds were on continuous light until 1 wk of age when the treatments were applied. Treatment 2 caused a significant reduction in 8- and 14-wk body weight when compared with treatments 3 and 4. Roasters on treatments 2, 3, and 4 had significantly less leg defects than those on treatment 1.
DISTRIBUTION OF EMBRYOS BETWEEN SIDES IN SWINE
Authors: SITTMANN K.
Published: March 2010

Using Parker and Bullard’s data (Proc. Amer. Acad. Arts Sci. 49: 399–426, 1913) on 1,000 litters of swine, a predictable pattern was determined for the distribution of implants between left and right uterine horns. In contrast to mice, left and right horns had almost equal numbers of implants. Variability of left–right distributions was less than binomial due to intrauterine migration (P < 0.05 in litter sizes 4–11). Deviations from the common pattern are described. Embryonic mortality appeared to enhance symmetry between sides only slightly.