bluuebunny/crossref_metadata_2025 huggingface dataset:
SUPPLEMENTAL PROTEIN NEEDS OF FINISHING STEERS FED CORN SILAGE
Authors: MOWAT D. N. , SMITH O. B. , MACLEOD G. K. , SNODDON P. M. , MCKNIGHT D. R.
Published: March 2010

Three experiments involving a total of 300 steers were conducted to determine the effects of duration of protein supplementation of finishing steers fed moderate to high levels of corn silage. Hereford and Hereford-cross steers were utilized in two experiments, and Holstein steers in the third study. Growth rate and feed intake suggested that protein supplementation could be withdrawn from a basal diet containing approximately 9.0% crude protein with Hereford or Hereford-cross steers initially in moderate condition after they reach approximately 400 kg liveweight. Holstein steers in thin condition at the start of the experiment appeared to require protein supplementation until a liveweight of 410–450 kg. Protein supplementation had little or no effect on carcass measurements in all three experiments.
NUTRITIVE VALUE OF WHOLE CROP SILAGE MADE FROM SEVEN CEREAL CULTIVARS
Authors: CHRISTENSEN D. A. , OWEN B. D. , STEACY G. , MTIMUNI J. P. , CROWLE W. L.
Published: March 2010

Seven cultivars of barley, oats and wheat were harvested at the mid-dough stage and stored in polyethylene-covered experimental silos of 700-kg capacity. Four steers weighing about 200 kg were fed each type of silage in order to determine voluntary intake and digestibility of energy and protein. The silages averaged 36.6% dry matter and 12.5% crude protein, with the wheat and barley silages containing significantly more protein than oat silage (P < 0.05). Digestibility of energy averaged 65.4%. The wheat and barley cultivars tended to contain higher digestible energy levels than oat cultivars. Digestibility of crude protein averaged 68.5% with no significant differences. Voluntary intake of dry matter (DMg/Wkg.75) was higher (P < 0.05) in oats than barley or most wheat cultivars. Intake of Glenlea wheat equalled Fraser oats and the unlicenced 1863–4 oat cultivar.
STUDIES WITH HORSES COMPARING 4N-HCl INSOLUBLE ASH AS AN INDEX MATERIAL WITH TOTAL FECAL COLLECTION IN THE DETERMINATION OF APPARENT DIGESTIBILITIES
Authors: SUTTON E. I. , BOWLAND J. P. , McCARTHY J. F.
Published: March 2010

Three series of digestibility experiments with mature geldings indicated no significant differences between the 4N-HCl insoluble ash indicator and the total collection methods for determination of apparent digestible nitrogen and digestible energy. There were significant differences (P < 0.05) between animals for the insoluble ash method in two of the three trials. No significant differences were found when the number of sampling days involved was reduced from 7 to 4 days and random grab samples of feces were used for insoluble ash determinations. Random grab samples taken for 1, 2, 3 or 4 days did not give significantly different digestion coefficients using the insoluble ash indicator method. Period differences in the insoluble ash method were observed when 3-day collections during five successive periods were taken from four individual geldings by the grab method. A study with four geldings during two test periods using cotton strips as indicators showed mean rate of passage of digesta to be 70.2 h. The overall results suggest that random grab fecal samples using the 4N-HCl insoluble ash method has potential for use in the determination of digestibility coefficients for horses.
THE CALCIUM AND MAGNESIUM CONTENT OF SILAGE CORN AS AFFECTED BY FREEZING
Authors: WHITE R. P. , WINTER K. A.
Published: March 2010

The Ca and Mg levels in silage corn progressively declined after a killing frost; significant losses (P = 0.05) occurred within 10–20 days. Data on declining dry matter yields and N, P, and K levels were also noted. Delayed harvesting of frozen corn will intensify the already low mineral content of corn silage as a feed.
VOLUNTARY INTAKE AND DIGESTIBILITY OF SLOUGH HAY AND DEHYDRATED ALFALFA PELLETS BY RAMS AND STEERS
Authors: ANDERSON D. M. , CHRISTENSEN D. A. , CHRISTISON G. I.
Published: March 2010

Dehydrated alfalfa pellets (dehy) and slough hay (Carex and Calamagrostis spp.) were fed to growing steers and rams. Both steers and rams consumed dehy (5.80 kg/day and 1.75 kg/day, respectively) at a significantly higher rate (P < 0.05) than the slough hay (4.22 kg/day and 0.81 kg/day, respectively). Forage energy digestibility did not differ for steers (dehy 51.1% and slough hay 49.9%) but did for rams (P < 0.05) (dehy 59.5% and slough hay 51.6%). Both species showed greater digestibility of protein and nitrogen-free extract for dehy and greater fiber digestibility for slough hay (P < 0.05).
IDENTIFICATION OF OVARIAN FOLLICLES AT ESTRUS AND DEVELOPMENT OF THEIR ENSUING CORPORA LUTEA IN SINGLE AND MULTIPLE OVULATING EWES ON TWO FEEDING REGIMES
Authors: DUFOUR J. J. , MATTON P.
Published: March 2010

Twelve hours after standing estrus was first detected, 30 ewes had their four largest follicles identified and marked with India ink. Seven days later, ovulation rates and origin of the corpora lutea (CL) from previously marked follicles were determined. Feeding a high energy ration from day 10 to estrus did not change the ovulation rate as compared to feeding a low energy ration. Its only effect was to increase the diameter of the third and fourth largest follicles. The diameter of the largest follicle was identical in single and multiple ovulators. However, in multiple ovulators, the diameter of the second largest follicle was larger than in single ovulators. The largest follicle identified at estrus developed into a CL that was 15% heavier in single than in multiple ovulators. In multiple ovulators, the second largest follicle developed into a CL of weight similar to that from the largest follicle.
A COMPARISON OF BIRTH GROWTH AND CARCASS CHARACTERISTICS BETWEEN HOLSTEIN-FRIESIAN STEERS AND CHAROLAIS × HOLSTEIN (F1) CROSSBREDS
Authors: FORREST R. J.
Published: March 2010

The growth and carcass characteristics of 12 purebred Holstein-Friesian steers were compared with 18 (12 steers and 6 heifers) Charolais × Holstein, F1 crossbreds. The rates of growth were similar for the three groups except for the 400- to 500-kg growth phase when the females, Holstein and crossbred steers gained 1.25, 1.47 and 1.69 kg/day, respectively. After slaughter at 500 kg, the crossbreds were found to have significantly (P < 0.05) heavier hides and hindquarters and lighter stomachs and livers than the purebreds. The females had the greatest amount of offal fat (stomach, kidney, cod plus channel) (35.1 kg), and the crossbred males the least (24.3 kg). The crossbreds were significantly (P < 0.05) shorter in body length, wider at the shoulders and rumps and had greater circumference in the round than the purebreds. Since the average birthweights were similar in all three groups (47 ± 0.6 kg), these structural differences appeared to be the major cause of dystocia in the crossbreds, particularly in the case of primiparous heifers.
EFFECTS OF A CHELATED TRACE MINERAL SUPPLEMENT ON THE COPPER AND IRON STATUS OF WINTERING PREGNANT BEEF COWS FED HAY OR GRASS SILAGE
Authors: HO S. K. , HIDIROGLOU M. , JENKINS K. J. , WAUTHY J. M. , PROULX J.
Published: March 2010

In late autumn, 60 gestating Shorthorn cows were assigned at random to one of two feeds (hay or grass silage) and one of three trace mineral supplements (none, sulfates or chelates) to form six groups of 10 animals each. The group of cows fed grass silage exclusively as a maintenance diet and without trace mineral supplementation developed progressively lower blood plasma copper levels compared with those fed only hay. In early summer of the following year, more than half of this group was hypocupremic and the mean blood plasma copper level (< 0.5 μg/ml) was lower than that of the other five groups. This difference was also observed in the level of copper in the milk of the cows before they were turned out onto pasture. In both feeds, there were no differences in consumption of mineral supplements between groups, and the copper intake from the group supplemented with chelates was about 14% of that of the respective group supplemented with sulfates. In terms of plasma iron, hemoglobin level and packed cell volume of whole blood, body weights of the cows and birth weights of their calves, there were no differences when groups with trace mineral supplementation were compared to those without.
EVALUATION OF HIGH FAT OATS IN RATIONS OF GROWING AND FINISHING RUMINANTS
Authors: DEVLIN T. J. , INGALLS J. R. , SHARMA H. R.
Published: March 2010

Growth and digestion trials were conducted to evaluate high fat oats (HFO) with Holstein calves, beef calves, yearling steers and wether sheep. In trial 1, 20 Holstein calves were fed calf starter diets containing either 90.2% HFO or regular oats (RO). Daily feed intake (3.31 vs. 3.23 kg), average daily gain (0.88 vs. 0.81 kg) and feed/gain ratios (3.80 vs. 4.03) were not different (P > 0.05) for the HFO- and RO-fed calves. Apparent digestibility of dry matter (DM), crude protein (CP) and gross energy (GE) were similar (P > 0.05) for the two treatments; however, digestion coefficient of ether extract (EE) was higher (P < 0.10) for the HFO diet compared to RO diet. In trial 2, 72 beef calves were self-fed diets containing 50% ground barley straw with six treatment grain mixtures (barley, HFO, RO, wheat, barley + faba beans, and RO + 3.6% tallow). Daily feed consumption and feed/gain were not different (P > 0.05) among the six treatments. However, animals receiving barley and 15% faba bean diet gained significantly (P < 0.05) less than the other treatments. In trial 3, 72 finishing steers were assigned to dietary treatments involving barley, RO, HFO, tallow and Ralgro implant. Feed consumption, average daily gain and feed efficiency ratios were similar (P > 0.05) among treatments. Addition of tallow to a RO diet fed to wether sheep (trial 4) decreased (P < 0.05) apparent digestibilities of DM and GE but HFO were similar (P > 0.05) in digestibility to RO.
MONENSIN FED TO GROWING AND FINISHING CATTLE
Authors: MOWAT D. N. , WILTON J. W. , BUCHANAN-SMITH J. G.
Published: March 2010

Two experiments were conducted to evaluate the effects of monensin with growing and finishing cattle. In experiment 1, 80 Hereford steer calves were fed two different silage rations. With alfalfa silage, monensin increased weight gains (+12%) and feed efficiency (P < 0.05) (+11%). When high moisture (HM) shelled corn was fed along with alfalfa silage, monensin had no effect on weight gains, but increased feed efficiency (P < 0.05) (+12%) largely by decreasing (P > 0.05) feed intake. In experiment 2, 72 steer and heifer crossbred calves were fed corn silage for 112 days followed by high levels of HM shelled corn through to marketing at a constant finish. Over an average total of 258 days on feed, monensin increased (P < 0.05) rate of gain (+9%) as well as feed efficiency (+13%). Monensin produced no effects on carcass characteristics. At least part of the improvement in feed efficiency could be attributed to altered ruminal fermentation. Molar percentage of propionic acid was increased (P < 0.05) and butyric and acetic acid decreased (P < 0.05) with monensin feeding.
LAYER PERFORMANCE IN COLONY CAGES AS RELATED TO STOCKING DENSITY AND POPULATION SIZE
Authors: HILL A. T.
Published: March 2010

Two commercial strains of White Leghorns were each measured for egg production, egg quality, feed efficiency and net egg income over feed and bird costs. The birds were in populations of 18, 24 and 30 per colony cage each at densities of 310, 387 and 464 cm2 per bird. In addition, a 10th population–density combination of 24 birds, caged singly at 619 cm2, served as controls. A total of 3,840 birds were measured for 60 wk in two tests, each with four replications. Results were also related directly to an earlier experiment with populations of 3, 6 and 12 birds per cage at the same densities. The performances of populations of 18, 24 and 30 birds were equal and poor relative to the controls. All three populations at 387 cm2 per bird were superior to those at 310 cm2 and equal to 464 cm2 in egg production and net egg income. In comparisons with more conventionally caged populations of 3, 6 and 12 birds, colony caged layers yielded significantly (P < 0.01) fewer eggs and less net egg income. Mortality was significantly (P < 0.05) greater for colony caged layers. It was concluded that the general high level of stress in colony cages prevented the expression of declining performance normally expected with population increases, yet effects due to density were still evident.
SELENIUM CONTENT OF FEEDSTUFFS GROWN IN ONTARIO
Authors: YOUNG L. G. , EDMEADES D. M. , JENKINS K. J.
Published: March 2010

The selenium content of 450 grain and 415 forage samples from 52 counties or areas in Ontario was determined. All areas surveyed produced some samples which contained 0.03 ppm selenium or less. Seventy-nine percent of the grain and 86% of the forage samples contained less than 0.10 ppm Se, the minimum recommended dietary requirement for animals. There was considerable variability in the Se content of samples within counties or regions.
NUTRITIVE VALUE OF WHOLE CROP CEREAL SILAGES
Authors: CHRISTENSEN D. A. , STEACY G. , CROWLE W. L.
Published: March 2010

Voluntary intake and digestibility of protein, dry matter and energy of nine cereal silages were determined using 200-kg steers. Digestible energy intakes were lower for spring rye (Gazelle) and tillering corn silage (Stewart Multi T) than for wheat, oats, barley and non-tillering corn silages (Pride R102). Intake of DE was highest for Neepawa wheat silage. The tillering corn was less mature (16.0% dry matter) than the other cereals which were harvested at the mid-dough stage. Digestibility of protein was significantly lower in the rye and corn silages than in the other silages.
A COMPARISON OF EQUAL-SIZED VERSUS PROPORTIONAL-SIZED EVENING AND MORNING MILK SAMPLES ON FAT, PROTEIN AND TOTAL SOLIDS TESTS
Authors: IRVINE O. R. , McKNIGHT D. R.
Published: March 2010

Averages of 11 Holsteins for fat, protein and total solids were calculated from equal-sized night and morning samples and compared to those weighted proportionally to the night’s and morning’s milk yield. The former were significantly higher in the case of fat and total solids, but not for protein.
GROWING AND FATTENING OF PIGS IN RELATION TO TEMPERATURE OF HOUSING AND FEEDING LEVEL
Authors: VERSTEGEN M. W. A. , BRASCAMP E. W. , HEL W. VAN DER
Published: March 2010

Climatic and housing conditions in the fattening of pigs are discussed in relation to heat requirements and feeding level. Increase in feeding level will allow pigs to meet their thermal heat requirement at lower ambient temperatures. From fattening trials reported in the literature, mean feed intake, rate of gain, feed conversion, backfat thickness and lean meat to fat ratio have been computed at temperatures of 5, 10, 15, 20 and 25 °C. Feed intake was lowest at 25 °C. Rate of gain was maximal and feed conversion (ratio feed intake: liveweight gain) was minimal at about 20 °C. At computed similar intakes of feed, rate of gain decreased with 15 g/°C below 20 °C. Backfat thickness was as a mean decreased in the cold, as was lean meat to fat ratio. Optimum feeding level for feed conversion may be increased to above 80% of ad libitum intake.
EFFECTS OF ACUTE COLD EXPOSURE ON PLASMA CONCENTRATIONS OF NORADRENALINE AND ADRENALINE IN SHEEP
Authors: THOMPSON J. R. , CHRISTOPHERSON R. J. , HAMMOND V. A. , HILLS G. A.
Published: March 2010

Six acute cold trials were performed with mature wethers shorn to a fleece depth of 5–10 mm and maintained in a controlled environment chamber. Heart rate, hematocrit and plasma concentrations of glucose, noradrenaline (NA) and adrenaline (A) were measured during each trial which consisted of a 90-min period at 25 °C, a 150-min period of cold stress (to −19 °C) and a 120-min warming period. All measurements and samples were taken from outside the controlled environment chamber by means of extended conduits to minimize animal disturbance. Mean values at 25 °C were: heart rate 69 beats/min, hematocrit 26.7%, plasma glucose 62 mg/100 ml, NA 0.24 ng/ml and A 0.07 ng/ml. By 120- to 150-min cold exposure, mean values of all variables had increased (P < 0.001) to: heart rate 223 beats/min, hematocrit 33.1%, plasma glucose 115 mg/100 ml, NA 1.11 ng/ml and A 0.24 ng/ml. Following cold exposure, mean values of all variables returned toward pre-cold period values as chamber temperature approached 25 °C. A seventh trial performed at constant temperature (24 °C) demonstrated the marked elevation in plasma catecholamine concentrations when an experimental animal was disturbed. These trials demonstrated: (a) that plasma NA and A concentrations in resting unrestrained ruminants are similar to those of other animals in the same state, (b) that it is important to minimize animal disturbance while studying catecholamines, and (c) that he sympatho-adrenal medullary system is involved in the physiological response of sheep to acute cold stress.
EFFECTS OF INORGANIC SULFATE SUPPLEMENTS ON THE GROWTH OF RATS FED SULFUR AMINO ACID-DEFICIENT DIETS
Authors: JAMES K. A. C. , HOVE E. L.
Published: March 2010

Rats were fed sulfur amino acid-deficient diets supplemented with inorganic sulfate to test whether sulfate spared sulfur amino acids for growth. The dietary protein sources used were lupin kernels, alfalfa leaf protein concentrate, commercial casein, or purified casein; 10% protein diets were supplemented with sodium sulfate (1.5 g/kg) and/or various levels of DL-methionine. Sulfate did not improve weight gain or protein efficiency ratio when added to diets containing lupin kernels, alfalfa leaf protein concentrate, or commercial casein. The lack of response was probably due to the relatively high intrinsic non-protein sulfur or inorganic sulfate contents of the diets. When the intrinsic sulfate level was reduced to 0.003% as in the purified casein diet, added sulfate significantly improved weight gain and protein efficiency ratio.
A COMPARISON OF CROSSBRED AND PUREBRED BOARS FOR SEMEN AND REPRODUCTIVE CHARACTERISTICS
Authors: CONLON P. D. , KENNEDY B. W.
Published: March 2010

Crossbred Hampshire–Duroc boars were compared to purebred Hampshire, Duroc and Landrace boars for seven semen characteristics and for reproductive performance under competitive double mating. A total of 14 boars were represented: three Hampshire–Duroc, three Hampshire, three Duroc and five Landrace. Significant breed of boar effects were observed on semen volume (P <.01), sperm concentration (P <.10), concentration score (P <.05), morphology score (P <.10), live–dead rate score (P <.05) and total semen score (P <.01). Landrace and Hampshire–Duroc boars produced more than twice the volume of semen produced by purebred Hampshires and Durocs. Hampshire, Duroc and Hampshire–Duroc boars had greater sperm concentrations and concentration scores than Landrace. Hampshire–Duroc boars ranked highest for morphology and total semen scores, but lowest for live–dead rate score. When double-mated to Landrace sows, breed of boar had no significant effect on conception rate but significantly affected (P <.05) percent of litter sired. Hampshire, Duroc and Hampshire–Duroc boars sired almost twice as many pigs as the Landrace.
PROGENY TEST OF FINNISH AND CANADIAN AYRSHIRE BULLS FOR VEAL AND BEEF PRODUCTION
Authors: KENNEDY B. W. , JONES G. M. , CHICOINE R. L. , HICKMAN C. G. , BURNSIDE E. B.
Published: March 2010

An experiment was conducted to obtain progeny test comparisons of Finnish and Canadian Ayrshire bulls for veal and beef production. A total of 83 male calves from four Canadian and four Finnish sires was tested. Best linear unbiased estimates of differences between veal calf progeny of Finnish and Canadian bulls for time on test, average daily gain and feed conversion were 4.00 ± 5.63 days, −.044 ±.038 kg/day and.062 ±.067 kg dry matter intake/kg gain, respectively. For veal carcass traits, progeny differences between Finnish and Canadian bulls for dressing percent and carcass grade, quality, finish and color scores (scores ranged from 1 to 3, except for color score which ranged from 1 to 2, with high score desirable) were.25 ± 1.13%, −.085 ±.232,.146 ±.303,.122 ±.302 and.104 ±.192, respectively. When raised for beef, differences between Finnish and Canadian sired steers were.015 ±.019 kg/day for feedlot average daily gain and.21 ±.66% for dressing percent. None of these differences were significant (P >.05). Based on these results, the importation of Finnish semen would not be expected to materially change the veal and beef performance of Ayrshires in Canada.
PHOTOPERIOD-INDUCED CHANGES IN LH, FSH, PROLACTIN AND TESTOSTERONE SECRETION IN THE RAM
Authors: SANFORD LEE M. , PALMER W. MARTYN , BEATON D. BRUCE , HOWLAND BORDEN E.
Published: March 2010

Two "annual" reproductive–endocrine cycles were produced in rams during a 12-mo period by photoperiodic manipulation. Two Finnish Landrace rams were housed in a "light-proof" room between 21 Dec. 1974 and 21 June 1976; they were exposed to three consecutive photoperiod cycles in which the sinusoidal fluctuation in the annual daylight rhythm characteristic of Southern Manitoba was reproduced in 6 mo. Daylength started to decline on the 21st day of December and June. Light-controlled rams and two rams penned outside (controls) were bled at 3- to 5-wk intervals between mid-June 1975 and mid-June 1976. Jugular venous blood was collected at 20-min intervals for 8 h on each occasion. Sera were assayed for luteinizing hormone (LH), follicle stimulating hormone (FSH), prolactin (PRL) and testosterone. The onset of decreasing daylength was followed by increases in serum FSH and testosterone concentrations and a decrease in PRL concentration in both pairs of rams. However, photoperiod-related changes in serum LH concentration in rams were not comparable during 6- and 12-mo "annual" photoperiod cycles. In all rams, periods of elevated testosterone concentration were characterized by increases in LH- and testosterone-peak frequencies and testosterone-peak height, and a decrease in LH-peak height.
RAPESEED GUM IN FINISHING DIETS FOR STEERS
Authors: MATHISON G. W.
Published: March 2010

Fifty steers were fed ad libitum for 127 days to evaluate the effect on animal performance and nutrient digestibility of the addition of rapeseed meal and rapeseed gum to a feedlot ration containing a high level of barley. There were no beneficial responses (P > 0.05) in nutrient digestibility, feedlot performance or carcass characteristics when 5% rapeseed meal was added to a high-barley diet containing 10.8% crude protein. The addition of 0.1, 0.2 or 3% rapeseed gum to the diet also had no significant (P > 0.05) effect on any of the parameters measured.
GENETIC INFLUENCES ON GROWTH PATTERNS OF MUSCLE AND BONE IN YOUNG BULLS
Authors: JONES S. D. M. , PRICE M. A. , BERG R. T.
Published: March 2010

Carcass composition and growth patterns for muscle and bone were compared among three breed-types (Hereford crossbred, (HC), beef synthetic (SY) and dairy crossbred (DC)). Sixteen bulls of each breed-type were weaned at about 6 mo and fed a high concentrate ration ad libitum. The bulls were grouped four to a pen and randomly allocated to one of two slaughter weights (500 kg and 600 kg). Breed-types differed (SY vs. HC and DC) in the allometric growth coefficients of hot carcass weight regressed on liveweight indicating that the growth of the hot carcass relative to liveweight in SY bulls was higher than the interbreed average. No significant breed-type differences were found in the regression of sample muscle and bone on various size dimensions. Breed-types differed significantly in amount of bone adjusted to common sample muscle, carcass and liveweight. Since breed-type allometric regressions were in all cases homogeneous, the difference in composition reflected differences already apparent at the first slaughter point (500 kg).
EFFECTS OF BREED AND SEX ON THE RELATIVE GROWTH AND DISTRIBUTION OF BONE IN CATTLE
Authors: JONES S. D.M. , PRICE M. A. , BERG R. T.
Published: March 2010

The relative growth and distribution of bone from 256 bovine carcasses were compared among three breed-types (British, up to 30% Charolais and 30–50% Charolais) and three "sexes" (heifers, steers and bulls) over a wide range in carcass weight. The growth pattern for each bone relative to total side bone was estimated from the growth coefficient, b, in the allometric equation (Y = aXb). Growth coefficients were homogeneous among both breed-types and sexes for each bone relative to total side bone, indicating that different breeds and sexes followed similar patterns of relative bone growth as they increased in size. The lowest growth coefficients in the carcass were found in the neck and limb bones all of which had growth coefficients significantly less than 1.0. The thoracic and lumbar vertebrae and the sternum had growth coefficients not significantly different from 1.0 and the ribs, pelvic and pectoral girdles had growth coefficients significantly greater than 1.0. Significant breed-type and "sex" differences were found in the weights of individual bones when adjusted to equal side bone weight. However, these were small and probably reflected differences in stage of maturity.
PERFORMANCE OF EGG-STRAIN BIRDS DURING THEIR COMMERCIAL LIFE CYCLE WHEN CONTINUOUSLY FED DIETS CONTAINING TOWER RAPESEED GUMS
Authors: SUMMERS J. D. , LEESON S. , SLINGER S. J.
Published: March 2010

In response to queries regarding the long-term effect of utilizing rapeseed gums in poultry diets, an experiment was initiated in which this product was continuously fed throughout the life cycle of the laying hen. Treatments consisted of: (1) soybean meal control, (2) 15% Tower rapeseed meal (3) 15% Tower rapeseed containing 1.5% of rape gums (4) soybean meal containing 1.5% of rape gums, and (5) soybean meal containing 1.5% of soy gums. The meals containing gums were manufactured in Western Canada. The diets were offered to one commercial White Leghorn and University strains of White Leghorns and Rhode Island Red, with conventional dietary specifications used in relation to age of bird. Gums had no persistent effect on feed intake or body weight of pullets from day of age to 20 wk. During this period mortality was low and not influenced by diet. In a subsequent laying period of 308 days, these same dietary treatments had no significant effect on egg production, while breed differences influenced all parameters measured. The addition of gums to rapeseed meal caused a reduction in egg size for a commercial strain of White Leghorns while the converse was true for a Guelph strain of White Leghorns. This apparent dichotomy may have been related to differences in feed intake. Diet had no influence on fertility or hatchability or on the performance of subsequent offspring when these were fed diets comparable to those of their dams. It is concluded that no toxic effects in terms of productive performance accrue from the use of up to 15% Tower rapeseed meal which contains 1.5% rapeseed gums, when fed throughout the commercial life cycle of egg strain birds and their offspring. Performance data also indicate that the addition of such gums to soybean meal offers an alternative means of their disposal.
HIGH-PROTEIN WHEAT IN DIETS FOR LAYING HENS
Authors: GARDINER E. E. , DUBETZ S.
Published: March 2010

High-protein wheat (21.0%) and regular-protein wheat (14.5%) were compared at two dietary protein levels with and without supplementary L-lysine. The diets were fed to White Leghorn laying hens maintained in floor pens for 44 wk. The addition of 0.3% L-lysine increased egg production from all diets, although the increase with the 17.4%-protein diet was not significant. L-lysine supplementation increased egg weight with the high-protein wheat diets but not with the regular wheat diets. Feed consumed per dozen eggs was lowest when hens were fed regular-protein wheat supplemented with L-lysine. L-lysine supplementation of the high-protein wheat in the 16%-protein diet reduced the amount of feed required per dozen eggs. Body weights of hens were not affected by L-lysine supplementation of the regular wheat diet; however, supplementation of the high-protein wheat diets resulted in increased body weights. The use of high-protein wheat in the diets that were not corrected for protein (i.e., 17.4%-protein diet) did not support high rates of lay, egg size, and body weight unless supplemented with L-lysine.
A LABORATORY EVALUATION OF ORGANIC ACIDS AND FORMALDEHYDE AS PRESERVATIVES FOR WET CAGE LAYER EXCRETA INTENDED FOR RECYCLING BY FEEDING TO LIVESTOCK
Authors: SMITH O. B. , MOWAT D. N. , MACLEOD G. K. , MORAN JR. E. T. , FOX C. A.
Published: March 2010

A previous study on the feeding value of wet cage layer excreta (CLE) indicated the need for a chemical preservative to stabilize CLE and control odor. An acetic–propionic acid mixture, formaldehyde, and an acetic–propionic acid-formaldehyde mixture were evaluated as preservatives during a 28-day storage period. Two-kilogram amounts of 3-day-old CLE were treated with the three chemicals each at 0.25% (low rate), 0.50% (medium rate) and 1.0% (high rate) wt/wt. Each excreta sample was inoculated with 5 × 106Salmonella infantis/g. All treatments were replicated twice and stored uncovered at 22 °C. Discoloration, mold growth and putrefaction as well as changes in pH, dry matter, total nitrogen, ammoniacal nitrogen and volatile fatty acid content of samples taken at 0, 7, 14 and 28 days after treatment were the criteria of evaluation. Total Coliform count and Salmonella recovery were also recorded. The acetic–propionic acid mixture appeared most effective in retarding physical deterioration, especially mold growth and discoloration. All three chemicals were equally effective (P >.05) in reducing nitrogen losses. A level × time interaction effect (P <.05) was obtained for all parameters. Compared to the control, the medium and high rates of treatment effectively retarded deterioration for 7 and 14 days, respectively. The rise in pH, nitrogen losses, ammoniacal nitrogen and butyric acid content of samples treated at the medium and high rates were lower (P <.05) than for the control, and spoilage was less extensive. Beyond 14 days, spoilage and nitrogen losses were similar (P >.05) to that observed in the control. The low treatment rate was in general ineffective in preventing spoilage and nitrogen losses. Total Coliform counts decreased with time, and Salmonellae recovery was nil from 7 days post-inoculation for all treatments including the control.
MUCOPOLYSACCHARIDES AND GLYCOPROTEINS OF AVIAN SKIN: COMPARISONS OF METHODS OF ISOLATION AND ANALYSES OF FRACTIONS
Authors: ALBRIGHT J. E. , HENNEBERRY G. O. , ANASTASSIADIS P. A.
Published: March 2010

Mucopolysaccharide peptide complexes were isolated from avian skin by enzymatic (pepsin–trypsin or papain) hydrolytic procedures each followed by two ways of precipitation: (a) step-wise addition of ethanol or (b) addition of cetyl pyridinium chloride solution and ethanol. Respective precipitates predominantly contained (a) mucopolysaccharide–peptide complex(es) and (b) carbohydrate part of glycoprotein–peptide complex(es). The fractions were analyzed for hexosamine, hexuronic acid and sugars. The results indicated (a) that avian skin contains substantial amounts of both mucopolysaccharides and glycoproteins and (b) that pepsin–trypsin and papain hydrolyses were capable of liberating from avian skin comparable amounts of materials. Gas–liquid chromatography of the fractions indicated that glucosamine, glucuronic acid and galactose are more prevalent than galactosamine, galacturonic acid and mannose.
PERFORMANCE AND CARCASS QUALITY OF BROILER TOM TURKEYS SUBJECTED TO A POST-HATCH FAST AND OFFERED STARTING RATIONS OF DIFFERENT NUTRIENT CONCENTRATION
Authors: MORAN Jr. E. T.
Published: March 2010

Commercial source, medium-type male poults were either placed in floor pens with food and water within 6 h after hatching or delayed a subsequent 24 h. Starting feed offered in each case was either of a normal (28% crude protein and 2,850 kcal ME/kg) or high (30% and 3,040 kcal) nutrient concentration. During the initial 2 wk, birds that had been fasted gained less weight but had a better feed conversion than those placed early. Poults which received a ration having a high nutrient concentration gained more weight and had a better feed conversion than those offered the normal diet. Mortality at this time was greater with birds subjected to a fast than those placed early. Having access to the higher nutrient concentration ration led to a greater mortaility than if the normal diet was employed. Body weight differences established during the first 2 wk remained throughout the experiment. Feed conversions of rations common to all groups during the subsequent 2- to 6-, 6-to 10- and 10- to 14-wk periods were not influenced by the early treatments after 6 wk of age. Slaughter at 14 wk did not reveal any differences in apparent carcass yield, conformation or finish grade. Degree of fleshing was reduced when poults were subjected to a post-hatch fast and partially improved when the high nutrient starting diet was fed. Effects of fasting and early nutrition on mortality and carcass changes are explained in terms of biochemical events occurring with the neonate.
MAXIMUM LIKELIHOOD ESTIMATION OF GENETIC PARAMETERS IN CANADIENNE, BROWN SWISS, AND MILKING SHORTHORN
Authors: SZKOTNICKI W. D. , TONG A. K. W. , KROTCH K. M. , SHARABY M. A. , JOHNSON L. P. , SCHAEFFER L. R.
Published: March 2010

The application of maximum likelihood estimation of variance components to all lactation milk and fat records of three dairy breeds was accomplished with relative computational ease. Discussion of some of the practical problems of maximum likelihood estimation for the mixed model with sires and cows nested within sire is presented. Further study of a few of these problems is warranted. The estimated heritabilities for milk and fat yields were.27 for all three breeds, and repeatabilities were.50, except for Milking Shorthorn where repeatability estimates were.53 and.52 for milk and fat yield, respectively.
EFFECTS OF DIETARY ROUGHAGE LEVEL ON THE FEEDLOT PERFORMANCE AND CARCASS CHARACTERISTICS OF BULLS AND STEERS
Authors: PRICE M. A. , MATHISON G. W. , BERG R. T.
Published: March 2010

An experiment is described comparing bulls and implanted steers fed diets containing three roughage levels (20, 50 and 80% alfalfa–brome hay) with two pens of four cattle in each ’sex’ × dietary roughage level subgroup. Cattle were about 12 mo old and 230 kg at the start of the trial. Each animal was slaughtered when it reached 500 kg. No significant castration × roughage level interactions were found for any of the feedlot or carcass traits studied. Increasing the level of roughage in the diet resulted in a significant decrease in average daily gain (P < 0.01) and an increase in average daily feed (P < 0.01) and feed per kilogram gained (P < 0.01) to 500 kg. Differences in daily digestible energy (DE) consumption and DE and feed cost per kilogram gained were not significant. Increasing the roughage level reduced all measures of carcass fatness (P < 0.05) but had no significant effect on the muscle content. Castration significantly reduced growth rate (P < 0.01) and increased feed requirement per unit of gain (P < 0.05). Steer carcasses were lighter (P < 0.01) and fatter (P < 0.01) than those of bulls and had lighter sample muscle weights (P < 0.01) and smaller sample muscle:bone ratios (P < 0.01).
PROGESTERONE BLOCKADE OF ESTROGEN-INDUCED LH RELEASE IN ANESTRUAL EWES
Authors: HOWLAND B. E. , SANFORD L. M. , PALMER W. M.
Published: March 2010

A release of luteinizing hormone (LH) was induced in anestrual ewes following an injection of 50 μg or 1 mg estradiol-17 β (E2). Daily injections of 30 mg progesterone, ending 4 h before estrogen, were completely effective in blocking the induced LH release if begun at least 1 day before 50 μg E2 or 3 days before 1 mg E 2. Ewes releasing LH had an accompanying release of follicle-stimulating hormone.
DIFFERENCES IN CARCASS PROPORTIONS AND COMPOSITION IN CONTROL AND HORMONE-TREATED HOLSTEIN-FRIESIAN STEERS AND BULLS
Authors: FORREST R. J.
Published: March 2010

The carcass proportions and fat deposition were studied in 72 Holstein–Friesian males reared on an all-concentrate ration and slaughtered at 475 kg. One half were castrated at 136 kg body weight and 18 bulls and 18 steers were implanted with 200 mg progesterone plus 20 mg estradiol-17-β-benzoate at 340 kg. There was no evidence of any difference between steers and bulls nor of any effect of the hormone treatment for the tail, butt, tip, round or front shank portions of the carcass. Steers had proportionately more flank, short loin, brisket and back and less chuck than bulls. With hormone treatment the percentage of rib and belly decreased and the hind, rump and rear shank increased in steers. With bulls, implanting decreased the rear shank and hind and increased the belly section. In carcass composition the bulls had a higher percentage of bone than steers. Implanting decreased the fat and increased the lean percentage in steers but did not significantly affect the bulls.
SPERM PENETRATION OF LIVE AND DEAD OOCYTES WITHIN OVIDUCTS OF GILTS
Authors: DOWNEY B. R. , SEGAL N. B. , BAKER R. D.
Published: March 2010

Sperm penetration of live and dead (rapidly frozen to −196 °C) porcine follicular oocytes was studied by transferring combinations of fluorescein isothiocyanate-stained (S) and nonstained (NS) live and dead eggs into the oviducts of tubally-inseminated gilts. All oocytes to be transferred were recovered from preovulatory follicles of gonadotropin-treated gilts via ovariectomy or follicular aspiration in situ. Only oocytes with a full complement of expanded cumulus were used. They were rendered nonviable by plunging semen straws containing S or NS oocytes into liquid nitrogen and storing them for at least 7 days before rapid thawing. The freeze–thaw cycle, without cryopreservative, resulted in numerous ruptures of the vitelline membrane and presumably the death of all oocytes examined. However, the zona pellucida and cumulus cell mass remained intact. Neither freezing nor staining affected ova recovery post-transfer or sperm penetration. Upon recovery, sperm slits and similar numbers of accessory sperm were observed in the zonae of both frozen–thawed and freshly transferred oocytes. Polyspermy was not observed.
STEROID HORMONE LEVELS IN BEEF COWS DURING PREGNANCY TERMINATING IN NORMAL CALVING OR ABORTION AND WITH SINGLE OR MULTIPLE OVULATION
Authors: ADELAKOUN V. , MATTON P. , DUFOUR J. J.
Published: March 2010

Plasma estrogen and progesterone levels were studied in cows bearing one or more embryos during pregnancies that ended either normally or by abortion. Different pregnancy rates were obtained by administering 800 or 1,600 IU pregnant mare serum gonadotrophin to cows fed either a low or high energy ration. With an increasing dose of gonadotrophin, increases were observed in the percentage of animals responding, the ovulation rate and the variability in individual response. In calving cows bearing more than one embryo, the levels of progesterone and of estradiol-17β were consistently higher during pregnancy than in calving cows bearing only one embryo. The concentration of estrone was also increased in the former group but only during the first trimester. In multi-ovulating cows that aborted, the high progesterone levels found at day 10 after mating were soon followed by a marked decrease: this forecast the abortion which always occurred, although often at a much later date; estrone levels tended to be lower in aborting cows than in calving cows, although there was considerable variation between individual patterns. Estradiol-17β levels were also low in aborting cows, and the gradual increase throughout pregnancy that was characteristic of calving cows was always absent. These results show that early in pregnancy in cows that are to abort the progesterone secretion cannot be maintained and that estradiol, although it is less abundant than estrone, is a better indicator of the physiological state of pregnancy.
RESPONSE TO WEANING AT TWO TO FIVE WEEKS OF AGE BY THE YOUNG DAIRY CALF
Authors: WINTER K. A.
Published: March 2010

In two experiments Ayrshire and Holstein bull calves were weaned off whole milk onto dry feed at various ages, ranging from 14 to 35 days, to determine the earliest age at which calves may be weaned successfully. Ayrshire calves were weaned at 14, 21 and 35 days with no significant differences in weight gains or feed intake to 15 wk of age. Holstein calves were weaned off whole milk or fermented colostrum at 17, 21, 24, 28 and 35 days of age with no significant differences in weight gains and feed intake to 12 wk of age. Also, the feeding of either fresh whole milk or fermented colostrum did not sigificantly affect animal performance. Several calves weaned at less than 21 days, in each experiment, refused to eat dry feed. Post-weaning deaths of several calves weaned at 21 days were attributed to prolonged pre-weaning scours or illness at time of weaning. It was concluded that healthy male calves may be weaned successfully at 21 days of age but weaning should be delayed for calves afflicted with scours or other illness. Agressive eaters may be weaned as early as 14 days of age but some calves weaned at less than 21 days of age may encounter problems in adapting to dry feed.
NIPPLE FEEDING OF TWO TYPES OF PROTEIN SUPPLEMENTS TO CALVES
Authors: WADLEIGH J. A. , MOWAT D. N.
Published: March 2010

Sixty Holstein bull calves initially averaging 94 kg were used in a 2 × 2 factorial design to compare two methods of feeding supplemental skim milk or soyaflour. A high moisture shelled corn ration, supplemented with excess urea to give an average of 13.2% crude protein (dry matter basis), was fed ad libitum. Soyaflour or skim milk, providing an additional 80 g of crude protein per day, was fed either suspended in 1.2 ℓ of warm water in a nipple bottle in two equal portions every day, or was mixed dry into the basal ration. Calves were housed five per pen on slatted floors and were fed for 140 days to an average liveweight of 272 kg. No significant differences (P >.05) were found between treatments in gain, dry matter intake or feed/gain. Rumen strontium tracer and plasma glucose load tests suggested persistence of reticular groove closure with nipple feeding of protein supplements up to 272 kg average liveweight. A subsequent experiment utilized 24 of the nipple-trained calves. Twelve were abruptly switched to twice daily bucket feeding while 12 remained on nipple feeding of skim milk. Strontium tracer tests on days 0, 14 and 28 of the trial suggested extinction of reflex groove closure and/or mechanical failure of the groove in calves changed to bucket feeding. Groove closure was maintained in nipple-fed calves to 332 kg average liveweight.
CORRECTION FACTORS FOR FIRST, SECOND AND LAST TEST DAY MILK YIELDS
Authors: KENNEDY B. W. , SOLA GLORIA , MOXLEY J. E.
Published: March 2010

Record of Performance Plan A data were used to estimate bias and sampling error in the test interval method (TIM) of calculating lactation milk yields and to develop correction factors for first, second and last test day milk yields. After editing, the data consisted of daily milk weights on 1,886 lactations of 1,310 cows in 51 herds (42 Holstein, 4 Ayrshire, 4 Jersey and 1 Guernsey). Three different sampling schemes were considered: 12 tests per year at regular monthly intervals (12R), 12 tests per year at irregular intervals (12I) and 10 tests per year at irregular intervals (10I). Analysis of variance indicated the need for different correction factors for different ages of cow (2,3 and [Formula: see text]). Before correction, average differences between TIM and actual 305-day milk yields (bias) were 40.2, 38.4 and 34.1 kg for sampling schemes 12R, 12I and 10I, respectively. Standard deviations of the difference between TIM and actual 305-day yields were 138.5, 140.5 and 163.8 kg, respectively, for 12R, 12I and 10I. Correcting first, second and last test day yields reduced the bias to 13.5, 12.0 and 7.0 kg for 12R, 12I and 10I, respectively, but standard deviations were reduced only slightly. Average biases, when data were corrected for first and last test only, were 2.1, −0.1 and −7.5 kg respectively for 12R, 12I and 10I. It was concluded that TIM test day credits need only be corrected for first and last test.
A COMPARISON OF THE NUTRITIONAL VALUE OF CRAMBE AND CAMELINA SEED MEALS WITH EGG AND CASEIN
Authors: KORSRUD G. O. , KEITH M. O. , BELL J. M.
Published: March 2010

The nutritional values of Camelina sativa Crantz and Crambe abyssinica Hochst, two potential dietary protein sources, were compared to egg and casein by feeding the ether-extracted autoclaved meal of each cultivar as the sole source of protein in semipurified diets to young mice for 14 days. The dietary protein levels chosen were 8, 11, 14 and 17%. The crambe meals contained less crude fibre than the camelina meals. Only trace quantities of glucosinolates were found in camelina meal. Substantially higher levels of glucosinolates were found in the crambe meals and there was evidence of a small proportion of the glucosinolates having been hydrolyzed prior to assay. Weight gains, food intakes and protein efficiency ratios of mice fed camelina or crambe meal diets were consistantly lower than the responses of mice fed corresponding levels of egg or casein diets. Food intake increased as the level of camelina meal in the diet increased. It appears that growth depressing factors in both the camelina and crambe meals were significant. Effective removal or counteraction of the deleterious factors is necessary before the potential of the protein in these two meals can be exploited.
EVALUATION OF A DEHYDROGENASE ASSAY BASED ON TETRAZOLIUM REDUCTION FOR RAPID IN VITRO ESTIMATION OF FERMENTATION ACTIVITY IN RUMEN CONTENTS
Authors: JONES G. A. , HUMPHREY B. A.
Published: March 2010

Rumen contents obtained from fistulated steers fed brome–alfalfa hay was used to evaluate a dehydrogenase assay based on the reduction of 2,3,5-triphenyltetrazolium chloride (TTC) to triphenylformazan (TPF) for rapid in vitro estimation of fermentation activity. Maximum absorbance of TPF occurred at 485 nm over the pH range 3–10. TPF formed from TTC was stable to atmospheric O2. Absorbance decreased if TPF was exposed to light. In the presence of excess TTC, production of TPF in strained rumen fluid (SRF) at 39 °C was linear with elapsed incubation times up to at least 5 min. Dehydrogenase activity was abolished in the presence of air. It was significantly increased if the CO2 gas phase above SRF was replaced with N2 or H2, owing, at least in part, to an increase in the pH of the fermentation. The dehydrogenase activity of SRF was maximal at pH 7.8–8.0. Fractionation of SRF by differential centrifugation showed that about 50% of the dehydrogenase activity was associated with a protozoal fraction sedimenting at 188 × g, and 42% with a bacterial fraction sedimenting at 1,475 × g. Neither the cell-free supernatant obtained by centrifuging SRF at 21,500 × g, nor boiled SRF, nor the hay fed to the animals showed dehydrogenase activity. Whole rumen contents (WRC) showed a mean dehydrogenase activity that was 58% higher than that of SRF. The dehydrogenase activity of SRF was increased in the presence of substrates representing major plant carbohydrates, the greatest stimulatory effect being shown by ground brome–alfalfa hay. When rumen contents were sampled at the same time by stomach tube and through the fistula, the mean dehydrogenase activity of SRF prepared from the stomach tube samples was 137% higher than that of SRF prepared from the fistula samples. In an animal fed at 12-h intervals, the dehydrogenase activity of SRF rose within 2 h after feeding, declined for the next 6 h, and showed a second peak at 9 h. Activity then declined to the pre-feeding level. The dehydrogenase activity of WRC showed a similar pattern but the peaks of activity were less pronounced. It was concluded that dehydrogenase activity based on TTC reduction provides a simple and rapid means of estimating the fermentation activity of rumen contents which may reflect the availability of energy substrates to the microbiota.