bluuebunny/crossref_metadata_2025 huggingface dataset:
THE SIGNIFICANCE OF THE REDUCED FEED CONSUMPTION OBSERVED IN GROWING PIGS FED VOMITOXIN-CONTAMINATED DIETS
Authors: CHAVEZ E. R. , RHEAUME J. A.
Published: March 2010

Feeding trials were conducted to determine the significance of the reduction in feed consumption observed when growing pigs were fed complete diets containing approximately 6 ppm vomitoxin. Sixty Landrace weaners, weighing on average 22 kg, were randomly assigned to four dietary treatments. The dietary treatments were: (1) control cereal soybean diet fed ad libitum (mycotoxin free); (2) vomitoxin diet fed ad libitum in which 100% of the clean wheat included in the control diet was replaced by moldy wheat containing 10.32 ppm vomitoxin; (3) control diet fed restricted to the average daily intake of pigs fed the vomitoxin diet; and (4) upgraded vomitoxin diet fed ad libitum and containing approximately 20% more energy, crude protein, minerals and vitamins. Individual feed consumption was recorded daily for 12 wk. The control diet promoted significantly (P < 0.05) greater total body weight gains and also the greatest feed consumption. Body weight gains were not different (P > 0.05) for the vomitoxin and restricted control dietary treatments. The vomitoxin upgraded treatment resulted in greater total body weight gains (P < 0.05) than the vomitoxin treatment. During the 12-wk period, animals in the vomitoxin and restricted-control-fed groups consumed 71% as much feed as the control group fed ad libitum while the vomitoxin upgraded group consumed 77% as much as the control. Analysis for blood urea nitrogen, creatinine, plasma protein and alkaline phosphatase revealed no differences (P > 0.05) between dietary treatments. With respect to animal performance and blood biochemical profiles, the effect of vomitoxin appears to be primarily limited to feed acceptability and intake, with no apparent consequences on the metabolic function of the animal. Key words: Vomitoxin, deoxynivalenol, growing pigs, feed consumption
THE NUTRITIVE VALUE OF GROUND RYE AS A FEED INGREDIENT FOR ADULT LEGHORN HENS
Authors: PROUDFOOT F. G. , HULAN H. W.
Published: March 2010

One thousand and eighty Leghorn hens were used to evaluate the effects of feeding ground rye from 140 to 490 days at 0, 5, 10, 15, 20 and 25% of diets. Traits which exhibited dietary effects were hen-day egg production, sexual maturity, body weights and feed efficiency. The higher dietary levels of ground rye had an adverse effect on egg production and feed efficiency. Key words: Rye (ground), diet, Leghorn, hens
EFFECTS OF EARLY WEANING ON CALF GAIN AND COW PERFORMANCE AND INFLUENCE OF BREED, AGE OF DAM AND SEX OF CALF
Authors: BASARAB J. A. , NOVAK F. S. , KARREN D. B.
Published: March 2010

A study was conducted to determine the effects of early weaning and preconditioning to feedlot on calf gain and the effects of early weaning on cow weight and reproductive performance. A total of 390 cow-calf pairs in 1982 and 460 in 1983, representing four breed, three age-of-dam groups and two-sex-of-calf groups, were randomly assigned to either an early weaned (EW) or a late weaned (LW) group. In the fall of each year, EW calves were weaned 1 mo before LW calves and fed grain (up to 4.8 kg head−1 d−1) and hay during this period. EW calves gained approximately 0.5 kg d−1 less over the 1 mo fall test period than LW calves in 1982 (0.16 vs. 0.75 kg d−1) and 1983 (0.05 vs. 0.58 kg d−1). EW cows gained 0.32 kg d−1 more during this same period than LW cows in 1982 (0.86 vs. 0.54 kg d−1) and lost 0.21 kg d−1 less in 1983 (−0.10 vs. −0.31 kg d−1). These differences in gain did not result in significant weight differences between EW and LW cows entering the winter feeding period in either year. EW and LW cows lost a similar amount of weight over the winter feeding period in 1982–1983 (−0.13 vs. −0.12 kg d−1) and had the same weight after calving in 1983. However, during the winter feeding period of 1983–1984, EW cows lost less weight than LW cows (−0.22 vs. −0.30 kg d−1) and, thus, weighed 27.3 kg more than LW cows after calving in 1984 (468.3 vs. 441.0 kg). Weaning treatment had no effect on pregnancy rate, calf crop percentage or calving interval. Weaning treatment also had no effect on cow weight and gain, calf birth date and weight, calving interval or calf preweaning gain the following year. Interactions between weaning treatment and breed, age of dam or sex of calf were absent for most weight and weight gain parameters and for calving intervals. Calf weights were affected by breed, age of dam and sex of calf while calf gains over the fall test were affected by age of dam. Cow weights were affected by breed and age, calf crop percentage by breed and calving interval by age. Breed, age of cow and sex of calf effects for all other parameters were not significant. Key words: Beef cattle, beef calves, early weaning, preconditioning
INFLUENCE OF BIRTH DATE, SEX OF CALF, BREED GROUP AND AGE OF DAM ON PREWEANING PERFORMANCE OF RANGE BEEF CALVES
Authors: AHUNU B. , MAKARECHIAN M.
Published: March 2010

Preweaning data on 2856 calves covering a 14-yr period in three breed groups of range beef cattle: Hereford (HE), Beef Synthetic (SY) and Beef Crossbred (XB) were analyzed for birth weight, weaning weight and preweaning average daily gain (ADG). Year of birth, age of dam, sex of calf and breed group were considered as main effects. Calf birth date was used as a covariate in the least-squares analyses. Year of birth was a significant source of variation. The correlation coefficients between the least-squares constants for years and year of birth indicated a steady improvement in the preweaning traits over the 14-yr period. Bull calves exceeded heifers (P < 0.05) in all traits except for ADG in HE. Preweaning performance peaked in calves from 5- to 6-yr-old dams. Though heavier at birth, XB calves were excelled by SY calves at weaning primarily because of superior ADG recorded in SY, while HE was the lightest of the breeding populations. Breed group by sex of calf interactions for weaning weight and ADG were significant. In addition, declining multiplicative sex adjustment factors from birth to weaning in the HE and XB populations suggested that in view of their greater potential for growth, male calves might have been marginally disadvantaged by the poor nutritional environment provided by the dams. In the HE and SY populations, calf birth weights significantly increased with the progression of the calving season, but the stage of the calving season did not affect calf birth weights in XB. The linear effects of age of calf were generally significant for weaning weight while quadratic effects were significant only in the XB population. Key words: Beef cattle, preweaning traits
GENOTYPE BY DIET INTERACTION IN MICE SELECTED ON THREE DIETARY REGIMENS
Authors: McKAY R. I. , PARKER R. J. , GUENTER W.
Published: March 2010

The effect on 10-wk body weight of seven generations of selection in three nutritional regimens (corn, rye and wheat) for two growth related traits, adjusted body weight (ABW) or adjusted feed efficiency (AFE) was evaluated. Selected mice were 3.2 g heavier (P < 0.01) than mice from the diet control (DC) lines. No effects of selection regimen or differences between the two selected lines for 10-wk weight were significant (P > 0.05). During generation 8 a crossover study was undertaken. Mice from each line (ABW, AFE or DC) from each selection regimen were fed the corn, rye and wheat diets. Response was estimated as a deviation from the DC line fed the same diet. No significant (P > 0.05) regimen by diet interactions were detected in either the ABW or the AFE lines. However, mice in the ABW line tended (P = 0.18) to have higher final weights on test (approximately 1 g) when fed the selection diet compared to the two alternative diets. Key words: Mice, genotype by diet interaction, body weight, feed efficiency
COMPARISON OF TWO MATHEMATICAL MODELS IN FITTING LACTATION CURVES FOR PURELINE AND CROSSLINE DAIRY COWS
Authors: BATRA T. R.
Published: March 2010

Weekly milk yield of 2066 first, 1407 second, and 755 third lactation pureline and crossline cows was used to study environmental and genetic effects on the coefficients of the lactation curves derived by modified gamma and inverse polynomial functions. The inverse polynomial function provided a better fit than the modified gamma function based on comparison of R2 values. Coefficients of the two models were analyzed to evaluate environmental and genetic effects on the shape of the lactation curve. The model included station, year of calving, month of calving, age at calving, days open, line of sire, line of dam, interaction of line of sire with line of dam, and sires within line of sire. In addition, coefficients of the lactation curve were analyzed by another model which included station, year of calving, month of calving, age at calving, days open, breed additive, maternal, and heterosis effects. Effects of station, year of calving, month of calving, and days open were mostly significant (P < 0.05); however the effect of age at calving was not significant on the coefficients of the lactation curves. Significant (P < 0.05) line of sire and line of dam effects on the level of initial yield suggest that genetic improvement of this trait could be achieved through selection. Breed additive and maternal effects were mostly nonsignificant on the coefficients of the lactation curves indicating shape of the lactation curve could not be changed by selection. There was very little evidence of nonadditive genetic variation associated with the coefficients of lactation curves. Key words: Lactation curves, pureline, crossline, dairy cows
HIGH LEVELS OF SODIUM CHLORIDE IN SUPPLEMENTS FOR GROWING CATTLE
Authors: HARVEY R. W. , CROOM JR. W. J. , POND K. R. , HOGARTH B. W. , LEONARD E. S.
Published: March 2010

Two trials were conducted to evaluate the effects of high levels of sodium chloride in energy and (or) protein supplements on performance and digestive and metabolic parameters of growing beef cattle. In each trial, 24 Hereford steers averaging 196 kg initial weight were individually fed corn silage or fescue hay plus an energy and (or) protein supplement containing NaCl. Consumption of the low (LS) and high (HS) levels of NaCl was 22–23 g d−1 and 192–193 g d−1, respectively. In Trial 1 the high NaCl supplement tended to reduce gains and feed efficiency of steers fed silage whereas gains were similar for those fed low and high NaCl and fescue hay. In Trial 2, gains and feed efficiencies were similar for both NaCl treatments. Rumen fluid total volatile fatty acid concentrations were lower (P < 0.05) at day 70 of both trials with high NaCl. Steers fed high NaCl had lower rumen ammonia concentrations at days 56 and 70 of Trial 1, while no significant differences were noted at day 70 of Trial 2. Molar percentages of valeric acid were reduced at each sampling with high NaCl diets. Serum Na levels were similar for the two NaCl levels, whereas K levels were increased at day 70 due to high NaCl. Rumen liquid digesta flow rates were increased (P < 0.05) in animals fed the high NaCl supplements, whereas total solid digesta and soybean meal rate of passage were not affected by NaCl level in the supplement. Supplements containing high levels of NaCl do induce changes in rumen function but do not consistently affect animal performance. Key words: Sodium chloride, supplements, beef cattle, corn silage, fescue hay
COMPARISON OF SILAGES FROM DENSELY SEEDED AND CONVENTIONALLY SEEDED CORN FOR BEEF STEERS
Authors: NICHOLSON J. W. G. , BELANGER G. , BURGESS P. L.
Published: March 2010

Corn for silage was planted at two seeding rates (60 000 and 200 000 kernels ha−1) in three consecutive years and evaluated by determining yields, digestibility by sheep and performance of growing-fattening beef cattle fed the ensiled crops. Plant populations at harvest ranged over years from 53 000 to 63 000 plants ha−1 for conventional seeding and from 94 000 to 151 000 plants ha−1 for the dense seeding rate. Dense seeding increased whole-plant dry matter yield each year. Only in 1 year (1979) did dense seeding reduce the yield of dry matter in the whole ear or grain (P < 0.01). In the same crop year (1979) dense seeding reduced the dry matter and crude protein contents of the silage (P < 0.01) and the digestibilities by sheep of the dry matter and nitrogen were lower (P < 0.01) than for the conventionally seeded crop. In 2 years (1978 and 1979), when the silages were fed ad libitum with only a protein-mineral-vitamin supplement, the daily silage dry matter intake by beef cattle was lower (P < 0.01 or P < 0.05) and in 1979 the average daily gain (1.06 vs. 1.14 kg d−1) was lower (P < 0.01) with silage from the dense seeding. There were no significant differences in beef performance parameters (silage dry matter intake, daily gain, and efficiency of silage conversion to daily gain) in the third year when the silages were fed with ground barley. Dense seeding of corn for silage resulted in more beef production per hectare and provides a means of reducing productivity loss due to birds feeding on the ripening ears of corn. Key words: Corn, silage, beef, dense seeding, seeding rate
INFLUENCE OF DIETARY CALCIUM-PHOSPHORUS LEVELS ON CERTAIN MECHANICAL, PHYSICAL AND HISTOLOGICAL PROPERTIES AND CHEMICAL COMPOSITION OF BONES IN GILTS AND SECOND LITTER SOWS
Authors: GRANDHI R. R. , THORNTON-TRUMP A. B. , DOIGE C. E.
Published: March 2010

A 24 factorial design of treatments involving two breeds (Lacombe (L) and Yorkshire (Y)) and two dietary calcium-phosphorus (Ca-P) levels (100% or 150% of 1979 National Academy of Sciences-National Research Council recommended Ca-P levels) during finishing, gestation and lactation periods, was used to study the changes in certain mechanical, physical, chemical and histological characteristics of bones in gilts and second litter sows. Femur, 3rd metacarpal and 6th rib bones were collected from the right half of the 32 (16L + 16Y) gilts slaughtered at 159 ± 1 d of age and 46 (22L + 24Y) second litter sows slaughtered at the end of second gestation-lactation cycle. The mechanical properties, breaking force, bending moment, breaking stress and elastic modulus of femur and 3rd metacarpal bones, determined by flexture tests using an Instron Universal Testing Machine, were not significantly (P > 0.05) influenced by the dietary Ca-P levels in gilts or sows. Feeding 150% of NRC Ca-P levels during the finishing period increased (P < 0.05) the bone shaft diameter (23.2 ± 0.2 vs.22.3 ± 0.2 mm) in femurs and percent bone ash (60.5 ± 0.4 vs. 59.0 ± 0.4) and percent bone Ca (19.0 ± 0.5 vs. 17.0 ± 0.5) in 3rd metacarpals of gilts. The femurs and 3rd metacarpals of L gilts and sows had generally larger shaft diameters but lower bone strength, elastic modulus and bone cortex thickness than in Y pigs. The histological examination revealed no abnormalities in trabecular and cartilage structures of 6th ribs between sows fed different Ca-P levels. The results suggested that feeding 150% of NAS-NRC Ca-P levels during finishing, gestation and lactation periods produced some positive changes in bone characteristics of gilts and second litter sows with no identifiable changes in their ability to function. Certain bone characteristics were different between the two breeds and their response to dietary Ca-P levels varied between femur and 3rd metacarpals of gilts and sows. Key words: Calcium, phosphorus, bone characteristics, gilts, sows
IMPORTANCE OF FOLIC ACID ADMINISTERED DURING GESTATION ON HEMATOLOGICAL STATUS OF PIGLETS
Authors: MATTE J. J. , GIRARD C. L. , BRISSON G. J.
Published: March 2010

In a group of 88 litters (group A), 252 piglets were chosen to measure the effect of folic acid during gestation on hemoglobin (Hb), hematocrit (Ht) and liveweight of piglets at birth, 7 and 14 d after birth. Forty-three dams received 10 intramuscular injections of folic acid during gestation; 45 received no supplemental folic acid in addition to what was present in the diet. Results showed that supplemental folic acid during gestation counteracted the magnitude of the decrease in Hb [Formula: see text] and Ht [Formula: see text] during the first week after birth and tended to increase [Formula: see text] the liveweight of piglets during the second week after parturition. In an second group (group B), 131 piglets from 45 litters were used to measure the effect of folic acid supplementation during gestation on serum iron at 4 and 11 d of age. Twenty-one dams were treated with folic acid and 24 received no supplemental folic acid during gestation. Two weeks after birth, piglets liveweight tended to decrease [Formula: see text] when folic acid was administered to dams during gestation. Serum iron concentrations were similar between treatments at 4 d of age but tended to be slightly higher [Formula: see text] 11 d after birth in piglets from sows injected with folic acid during gestation. Because of the conflicting results, on growth rate, the interpretation of the effect of folic acid during gestation on piglets growth remains ambiguous. However, folic acid administration during gestation did not affect iron body reserves of newborn piglets. Key words: Sow, folic acid, gestation, anemia, piglets
IN VITRO DEGRADATION OF MIMOSINE BY MICROORGANISMS FROM THE ESOPHAGEAL SAC OF VOLES (Microtus arvalis)
Authors: KUDO H. , CHENG K.-J. , MAJAK W. , HALL J. W. , ARAI T. , OKI Y. , COSTERTON J. W.
Published: March 2010

The microbiota in the esophageal sac of voles fed either cubed alfalfa hay or concentrate pellets were assayed to determine their capacity to anaerobically degrade mimosine in vitro. Differences (P < 0.01) were found between the two diets during the growth phase. The sac contents of voles fed concentrate pellets degraded mimosine and 3-hydroxy-4-(1H)-pyridone (DHP) rapidly, but inocula from voles fed cubed alfalfa hay only hydrolyzed mimosine to DHP. Degradation of the pyridine ring occurred at the early stage of incubation, concurrently with microbial growth. Thereafter, degradation rates appear to have been almost negligible and very similar for both diets. These results agree with previous data obtained with ruminal microorganisms, where highly active inocula were also associated with animals on concentrate diets. Key words: Detoxification, hydrolysis, esophageal sac, mimosine, 3-hydroxy-4- (1H)-pyridone, voles
THE EFFECT OF A CHRONIC CATHETERIZATION PROCEDURE ON REGIONAL BLOOD FLOW AND CARDIO-PULMONARY PARAMETERS IN THE LABORATORY RAT
Authors: KITTS D. D. , YEE S. J. , SCHAEFER A. L.
Published: March 2010

A blood collection technique for conscious, catheterized, unrestrained rats was standardized. Regional blood flows to the heart, brain and viscera were significantly lower in the anaesthetized rat and followed the decline observed in cardiac output. A recovery of all measured physiological parameters to stable levels required approximately 20 min. Key words: Chronically catheterized rats, anaesthesia, blood gases, regional blood flow
EVALUATION OF MEADOWFOAM (Limnanthes alba) MEAL AS A FEEDSTUFF FOR BEEF CATTLE
Authors: MILLER R. , CHEEKE P. R.
Published: March 2010

Raw meadowfoam meal (MFM) was fed as part of a pelleted diet to growing beef steers at dietary levels of 0, 12.5 and 25%, with 14 animals per treatment. Over the test period of 84 d, there were no differences in growth rate, suggesting that raw MFM is an acceptable feed ingredient for growing beef cattle. Key words: Cattle, meadowfoam, Limnanthes alba
ANDROSTENONE, ANDROSTENOL AND ODOR INTENSITY IN BACKFAT OF 100- AND 130-KG BOARS AND GILTS
Authors: BRENNAN J. J. , SHAND P. J. , FENTON M. , NICHOLLS L. L. , AHERNE F. X.
Published: March 2010

Forty-nine boars and 13 gilts were fed ad libitum from 20 to 100 kg body weight. Fifteen boars and four gilts were slaughtered at 100 kg and the remaining animals were fed ad libitum or at 70% of ad libitum feed intake from 100 kg liveweight until they were slaughtered at 130 kg. Backfat samples were collected from the lumbar region of all pig carcasses at both slaughter weights, vacuum packaged and stored at −20 °C. Fat samples (10 g) were saponified and extracted with hexane and ether. Extracts were evaporated under nitrogen, and androstenol (5α-androst-16-en-3α-ol; 5α-androst-16-en-3β-ol) and androstenone (5α-androst-16-en-3-one; 5β-androst-16-en-3-one) were quantified by gas chromatography using 5α-androstane-3, 17-dione as internal standard. A trained panel of eight women scored the odor intensity of each fat sample on a scale of 1 (no odor) to 6 (strong odor). Androstenone was detected in backfat from all boars and concentrations ranged from 0.06 to 3.42 μg g−1 of fat with a mean value of 0.76 (±0.10, SEM) μg g−1. Five boars had no detectable backfat androstenol while the highest concentration recorded was 1.8 μg g−1 fat. Neither steroid was detected in gilt backfat. Odor intensity of fat samples heated by soldering iron or in sealed vials was greater (P < 0.01) for boars than for gilts. Boars weighing 100 kg had lower (P < 0.05) backfat odor intensity score and androstenone concentration than 130-kg boars. Androstenol concentration and odor intensity of fat were significantly correlated (r = 0.42; P < 0.05) with age of ad libitum fed boars. There was a significant quadratic response of odor intensity determined by vial test to increasing androstenol concentration in fat (R2 = 50%) but the relationship between odor score and steroid content was otherwise linear. The concentration of androstenol in boar backfat was only one-half of the androstenone concentration but it explained some variation in odor score over and above (7–16%) that which was explained by androstenone. Key words: Boar, odor, androstenone, androstenol, backfat
ADRENOCORTICAL RESPONSE OF CALVES TO TRANSPORT STRESS AS MEASURED BY SALIVARY CORTISOL
Authors: FELL L. R. , SHUTT D. A.
Published: March 2010

A new approach utilizing a "nonstressful" technique of saliva collection and determination of salivary cortisol by radioimmunoassay was used to monitor the adrenocortical response of calves to repeated transport stress. Four standardized trucking and sampling procedures were used with 19 calves previously trained to being mustered into a race (chute) and having saliva collected. Basal mean salivary xortisol levels in the 19 calves ranged from 0.3 ± 0.4 nmol L−1 to 3.4 ± 0.6 nmol L−1, and after 30 min of trucking manoeuvres (starting, turning, reversing and stopping), significant increases (P < 0.01) in mean salivary cortisol levels occurred on all four occasions to values ranging from 10.5 ± 1.4 nmol L−1 to 16.0 ± 2.3 nmol L−1. After a further 2 h of normal road transport mean levels of salivary cortisol were still significantly elevated (P < 0.05) and ranged from 4.0 ± 0.9 nmol L−1 to 11.3 ± 2.6 nmol L−1 in comparison with 0.5 ± 0.2 nmol L−1 to 1.4 ± 0.3 nmol L−1 for nine control calves (not transported). Salivary cortisol levels returned to pretreatment levels within 2 h post-transport. There was a tendency for Friesian calves, less than 1 mo of age, to have a lower adrenocortical response to transport than crossbred calves of the same age. No evidence was found for adaptation of the adrenocortical response of the calves to transport. Key words: Adrenocortical response, calves, transport stress, salivary cortisol
EFFECT OF LOW ZINC INTAKE DURING PREGNANCY ON PLASMA PROLACTIN, PROGESTERONE, PROSTAGLANDIN, CORTISOL AND PROTEIN CONCENTRATIONS OF EWES DURING THE PERIPARTURIENT PERIOD
Authors: FITZGERALD J. A. , EVERETT G. A. , APGAR J.
Published: March 2010

The effect of low dietary Zn intake upon several plasma endocrine and metabolic profiles was examined during late gestation in the ewe. Thirty adult, primiparous Finncross ewes were fed a low Zn diet with (+Zn, n = 14) or without (0Zn, n = 16) supplemental Zn in the drinking water starting day 1 of pregnancy. Although the mean prepartum progesterone and prolactin concentrations were lower (P < 0.05 and P < 0.01, respectively) in 0Zn than in +Zn ewes, the peak prolactin concentrations in 0Zn ewes at lambing were similar to +Zn ewes. Both basal and thyrotropin-releasing-hormone (TRH)-induced prolactin release were less (P < 0.01) in 0Zn ewes 2 d postpartum. Plasma concentrations of 13, 14-dihydro-15-keto prostaglandin F2α (PGFM) of ewes sampled within 45 min post-lambing were lower (P < 0.05) in 0Zn ewes. There was no difference in cortisol concentrations within 45 min after lambing between 0Zn and + Zn ewes. Plasma protein concentrations in 0Zn ewes were higher (P < 0.01) than those in +Zn ewes during pregnancy. In summary, these data show that low Zn intake in the pregnant ewe affected several endocrine and metabolic plasma parameters associated with normal pregnancy and parturition. Key words: Zinc, parturition, dystocia, feed intake, ovine
THE EFFECTS OF SULPHATE REMOVAL FROM THE DRINKING WATER ON THE PLASMA AND LIVER COPPER AND ZINC CONCENTRATIONS OF BEEF COWS AND THEIR CALVES
Authors: SMART M. E. , COHEN R. , CHRISTENSEN D. A. , WILLIAMS C. M.
Published: March 2010

Pregnant Hereford cows (n = 99) and heifers (n = 98) whose ration contained 10 mg Cu kg−1 DM and 20 mg Zn kg−1 DM were assigned to two treatments. The water supply (sulphated water) for one group contained 500 mg S L−1 as sulphates. The sulphates in the water (desulphated) for the other group had been decreased to 42 mg S L−1 by reverse osmosis. Changes in plasma and liver copper and zinc concentrations were monitored in the cows and their calves during the winter drylot and pasture periods. The initial plasma and liver copper concentrations in all cows indicated a deficient status. At calving, the plasma copper concentration had declined in both groups. The greatest decrease was evident in the cows on sulphated water. At calving, the liver copper concentration had declined in both water treatment groups but was lowest in the cattle on the sulphated water. After calving, plasma and liver copper concentrations in both groups increased; this increase was greatest in the cows drinking the desulphated water. Water treatment had no effect on the copper status of the nursing calves. Water purification had a positive effect on the body weights of first and second calf heifers. Although the zinc status was normal, the plasma zinc declined and liver zinc increased in the cows at calving. These changes were independent of water treatment. When the sulphur in the drinking water was decreased to 42 mg L−1 by reverse osmosis there was a positive effect on the copper status of beef cows. Further research is required into higher dietary copper intakes, as 10 mg Cu kg−1 DM was not adequate in improving the deficient copper status of these cattle. Key words: Water sulphates, copper, zinc, beef cattle
SUPPLEMENTATION OF SKIM MILK FED TO VEAL CALVES. PERFORMANCE, BLOOD PARAMETERS AND HEALTH
Authors: DREVJANY L. A. , JOHNSON P. L. , ALLEN O. B.
Published: March 2010

Twenty-four Holstein male calves, initially averaging 55 kg, were individually housed and randomly assigned to four dietary treatments. Skim milk alone or supplemented with emulsified powdered tallow was offered to provide diets with digestible energy (DE) of 54, 100, 123, and 147 kJ g−1 of digestible protein (DP) for treatments 1, 2, 3, and 4, respectively. Dietary fat content in the skim milk was 0.1%. The higher levels of fat in treatments 3 and 4 were introduced at days 28 and 56, respectively. Dietary dry matter intake level (g/calf/day) was similar in treatments 2, 3, 4 and lower in treatment 1. Increasing DE to 100 kJ g−1 of DP brought about significantly improved (P < 0.05) daily gains, efficiency of dry matter and protein conversion, lower blood urea levels and improved fecal fluidity, consistency and color. Higher inclusion of dietary fat (treatments 3 and 4) significantly increased the content of blood hemoglobin with a possible negative effect on the lightness of meat color. The overall efficiency of DM conversion into gain equalled (treatment 1) or was better (treatments 2, 3, 4) than that considered acceptable for commercial veal operations (1.65 kg kg−1 of gain). With the exception of the blood urea levels, widening of DE:DP ratio beyond 100:1 (kJ:g DP) was not justified on the basis of the evaluation criteria used above. Key words: DE:DP ratios, veal calves, emulsified tallow, blood urea
DIGESTION BY CATTLE OF UREA-TREATED, AMMONIA-TREATED, OR ROLLED HIGH-MOISTURE BARLEY
Authors: RODE L. M. , CHENG K.-J. , COSTERTON J. W.
Published: March 2010

A study was conducted to compare the feeding value of processed high-moisture barley (HMB) treated by rolling (R-HMB), adding 6% urea (U-HMB), adding 3% anhydrous amonia (A-HMB), or left untreated (W-HMB). After ensiling for at least 42 d, the four treated HMB were fed with timothy hay (1:1 on a dry matter basis) to four ruminally fistulated steers during four time periods in a 4 × 4 Latin square design. During each period, treated HMB was incubated in saccus in the rumen of steers fed the same HMB. Chromium sesquioxide was mixed with the HMB and served as an indigestible fecal marker. HMB dry matter (DM) remaining in bags after incubation was 96.9, 69.3, 91.6 and 95.0% after 12 h and 85.6, 46.9, 67.0 and 50.0% after 36 h incubation for W-HMB, R-HMB, U-HMB and A-HMB, respectively. Disappearance of DM in R-HMB was greater (P < 0.01) than in chemically treated HMB at all time intervals tested. Disappearance of DM in W-HMB was less (P < 0.01) than in chemically treated HMB at incubation times of 8–36 h but was similar at 1 and 4 h incubation. Examination of the barley hulls by scanning electron microscopy indicated that chemical treatment of HMB resulted in greater digestion of the hull, greater growth of bacterial cells, and less production of extracellular polysaccharides than physical treatment (rolling) of HMB. Starch digestibility was greater (P < 0.05) for steers fed R-HMB (86.8%) than for steers fed A-HMB (76.9%) or U-HMB (69.1%). No differences between treatments were observed in DM digestibility. Key words: Cattle, nylon bags, high-moisture barley, electron microscopy, ammonia, processing
EFFECT OF DIETARY CALCIUM AND PHOSPHORUS LEVELS ON PERFORMANCE, BONE BENDING MOMENT AND THE SEVERITY OF OSTEOCHONDROSIS AND LAMENESS IN BOARS AND GILTS SLAUGHTERED AT 100 OR 130 KG BODY WEIGHT
Authors: BRENNAN J. J. , AHERNE F. X.
Published: March 2010

Ninety-six crossbred gilts and 96 crossbred boars averaging 20 kg were assigned to a factorial arrangement of three dietary calcium-phosphorus (Ca-P) levels and two slaughter weights (100 or 130 kg). The Ca-P regimens were based on (1) National Academy of Sciences-National Research Council (NAS-NRC)(1979), (2) Agricultural Research Council (ARC) (1981) and (3) 130% of ARC (1981) recommendations for grower and finisher swine. All pigs were fed ad libitum grower diets (0.60–0.50, 0.81–0.63, 1.05–0.82% Ca-P) from 20 to 55 kg and finisher diets (0.50–0.40, 0.72–0.54, 0.94–0.70% Ca-P) to 100 kg or 130 kg liveweight. At 100 kg liveweight 16 boars and 16 gilts from each of the Ca-P treatment groups were selected at random and slaughtered. The remaining pigs within each Ca-P group were allowed feed ad libitum or at 70% of ad libitum from 100 kg until slaughter at 130 kg. There was no significant effect of the three respective dietary Ca-P regimens on average daily gain, average daily feed intake, or feed/gain ratio of pigs during the 20- to 100-kg growth period. Metacarpal bending moment and femoral ash content increased (P < 0.05) in response to the first dietary Ca-P increment. There was a significant (P < 0.05) positive response of femoral ash content but not of bone bending moment to the second Ca-P increment. The incidence and severity of osteochondrosis of the femur, humerus, radius and ulna and leg soundness scores were unimproved (P > 0.05) by feeding elevated dietary Ca-P levels. There was no significant effect of ad libitum vs. restricted feeding during the 100- to 130-kg growth period on bone ash, bone bending moment or cartilage condition scores. Boars had significantly (P < 0.01) greater average daily gain and lower feed/gain ratio during the 20- to 100-kg growth period but they had more severe (P < 0.01) osteochondrotic lesions of the elbow joint and a lower (P < 0.001) femoral ash content than gilts. Correlation coefficients between cartilage soundness scores and bone ash content or bending moment were nonsignificant (P > 0.05). The results suggest that while bone ash content and bending moment respond positively to elevated Ca-P levels in excess of NAS-NRC (1979) recommendations, the incidence and severity of joint lesions and leg soundness scores are not reduced by maximizing bone mineralization. Key words: Osteochondrosis, calcium, phosphorus, swine
ASSESSMENT OF COMPLETELY PELLETED DIETS FOR PERFORMANCE TESTING OF RAMS
Authors: WALTON J. S. , McBRIDE B. W. , MARTINEAU N. A. , BURGESS T. D.
Published: March 2010

Completely pelleted diets were fed to rams under a facsimile of Ontario Ram Performance Test procedures. Twenty rams were fed for 50 d on completely pelleted rations without impairment of growth rate and without any effects on rumen health or ingestive behavior. Key words: R.O.P. testing, rams, pelleted feeds, growth rate, rumen lining
EFFECTS OF EXERCISE, TRAINING AND SAMPLING LOCATION ON SELECTED PLASMA FREE AMINO ACIDS IN HORSES
Authors: RUSSELL M. A. , RODIEK A. V. , LAWRENCE L. M.
Published: March 2010

The effect of mild exercise and conditioning on selected plasma free amino acids was investigated to determine whether riding horses are acceptable for amino acid studies. Alanine, glutamine, glutamate, leucine, isoleucine and valine were not altered by 6 min of exercise at heart rates of 108–120 beats/min. Venous samples were representative of central circulation. Key words: Horses, exercise, plasma free amino acids
NAKED OATS IN GROWER-FINISHER PIG DIETS
Authors: MORRIS J. R. , BURROWS V. D.
Published: March 2010

One hundred and twenty-eight pigs were placed into four groups and each group was fed from approximately 32 to 97 kg liveweight one of four diets: a control corn-soy diet or one of three diets containing 30.0, 65.0 or 96.7% of Tibor naked oats. Total liveweight gains and carcass backfat and quality index values were not significantly different at the end of the 77-d growth period. Feed conversion of the oat diets was progressively improved as the amount of oats in the ration increased; probably because the energy content of the rations increased as the concentration of naked oat kernels with their 8–10% total lipid increased. Diets containing the higher levels of oats also produced a better carcass yield (or dressing percentage) than the control diet. Tibor naked oats are thus a suitable replacement for all or part of the grain corn and soybean meal in a grower-finisher pig ration. Key words: Pig, grower-finisher diets, naked oats, cultivar Tibor
CONSTRAINTS ON ANIMAL AGRICULTURE
Authors: WILLIAMS C. M.
Published: March 2010

Constraints on animal agriculture are varied and complex but it is necessary that they be understood in order to progress. In addition to biological constraints, economic, political and health-related issues of animal products as food for mankind must be appreciated. Key words: Constraints, animal, production
BIOLOGICAL CONSTRAINTS AFFECTING NONRUMINANT PRODUCTIVITY
Authors: BALL R. O. , ETCHES R. J. , HACKER R. R. , MORRISON W. D.
Published: March 2010

Certain biological constraints on the production of protein by pigs and poultry are identified. These constraints are discussed under disease and environment, growth, cartilage and bone metabolism, genetics and reproduction. Research emphasis and possible solutions are described briefly. Key words: Pigs, poultry, biological constraints, growth, reproduction
EVALUATION OF ESTABLISHED BREEDS OF SHEEP IN CANADA FOR DAILY GAIN AND BODY WEIGHTS
Authors: SHRESTHA J. N. B. , VESELY J. A.
Published: March 2010

Breed differences were assessed in the daily gain and body weights of 6356 lambs from the Federal-Provincial Canadian Record of Performance program. The breeds represented were Suffolk, Hampshire, Oxford, Lincoln, Columbia, Rambouillet, Dorset, Corriedale, Leicester, North Country Cheviot, Southdown and Finnish Landrace. Sources of variation due to the influence of year, sex, type of birth and rearing, age of dam, time of year of birth, breeder (flock) and interactions were determined together with linear regressions of daily gain and body weights at 50 and 100 d on age of lamb within breed. Significant interactions between breed and year showed that the ranking of breeds varied from year to year, probably due to sampling associated with the breeds that had fewer lambs assessed. Of the meat-type sire breeds, the Suffolk was superior in growth performance of lambs, followed by the Oxford, and Hampshire breeds. Lamb growth performance was intermediate in the Finnish Landrace Dorset, North Country Cheviot and Rambouillet breeds and lowest in the Corriedale, Leicester, Columbia, Lincoln and Southdown breeds. Key words: Sheep, breed, daily gain, body weights
PLASMA CONCENTRATIONS OF TESTOSTERONE, ANDROSTENEDIONE, DIHYDROTESTOSTERONE, 5α-ANDROSTANE-3α, 17β-DIOL, 5α-ANDROSTANE-3β, 17β-DIOL, AND ANDROSTERONE IN BULL CALVES: RESPONSE TO hCG
Authors: RAWLINGS N. C. , COOK S. J.
Published: March 2010

Plasma androgen concentrations were measured in bull calves sampled weekly from birth to 30 wk of age and in calves sampled every 30 min for 8 h at 6, 14, 22 and 30 wk of age, before and after administration of hCG (5 IU kg−1, i.v.). Mean plasma concentrations of testosterone rose to 20 wk of age and then fell, but were variable. Mean plasma concentrations of androstenedione rose to 14 wk of age and then declined. Mean plasma concentrations of 5α-androstane-3α, 17β-diol and 5α-androstane-3β,17β-diol did not change with age, but dihydrotestosterone and androsterone were elevated at 14 and 22 wk of age, respectively. The overall means were 0.9 ± 0.08 ng mL−1 for testosterone, and 0.6 ± 0.07 ng mL−1 for dihydrotestosterone. Other androgens were present at concentrations of < 0.3 ng mL−1. However, the total concentration of the 5α-reduced androgens exceeded that of testosterone in bull calves from birth to 28 wk of age. Changes in mean androgen concentration with age and in response to hCG appeared to be reflected primarily in changes in the amplitude of pulses in plasma androgen concentration. Significant increases in pulse amplitude for testosterone and androstenedione occurred in response to hCG in 14-, 22- and 30-wk-old bull calves and for 5α-androstane-3α,17β-diol in 30-wk-old calves. The developing bull calf differs from laboratory rodents in that there is no period of time during reproductive development when individual 5α-reduced androgens circulate in concentrations greater than testosterone. Key words: Bull calf, sexual maturation, androgens
EFFECTS OF ADRENALINE, OXYTOCIN AND 2-Br-α-ERGOCRYPTINE ON MAMMARY BLOOD FLOW IN THE LACTATING EWE
Authors: McBRIDE G. E. , CHRISTOPHERSON R. J.
Published: March 2010

The mammary blood flow (MBF) and heart rate (HR) responses to standing, lying, suckling, adrenaline (A), oxytocin and 2-Br-α-ergocryptine were studied in four lactating ewes. Posture had a variable effect on MBF. In three of the four ewes there was an increase (P < 0.05) and in one ewe a decrease (P < 0.05) in MBF as a result of lying. Heart rate recorded while the ewes were lying was significantly lower (P < 0.01) than while standing. Suckling resulted in an average decrease in MBF of 39% (P < 0.01) compared to standing values. Continuous infusion of A at a rate of 300 ng kg−1 min−1 for 2.5 h resulted in a progressive increase in HR (P < 0.05) for 2 h of the infusion. During the A infusion MBF decreased transiently for 10–15 min and then increased thereafter (P < 0.05) throughout the A infusion in three of the ewes. In the fourth ewe, MBF increased to a peak during hour 2 of A infusion and thereafter declined. Exogenous oxytocin administered at doses [Formula: see text] had a stimulatory effect on MBF. Suckling and handmilking induced decreases in blood flow of 39 ± 6% and 54 ± 13%, respectively, after injection of 1 mU kg−1 oxytocin. Treatment of ewes with 2-Br-α-erogcryptine (a prolactin-release inhibitor) did not influence mean MBF while standing or lying but attenuated the negative effects of suckling and hand milking on MBF. Mammary blood flow in the lactating ewe is, therefore, sensitive to posture, suckling and hand milking but the response to the latter two activities could not be attributed to oxytocin on the basis of the present results. Key words: Mammary artery, suckling, milk, hormonal effect
EFFECT OF SELENIUM SUPPLEMENTATION ON COPPER METABOLISM IN DAIRY COWS
Authors: BUCKLEY W. T. , HUCKIN S. N. , FISHER L. J. , EIGENDORF G. K.
Published: March 2010

Eight Holstein cows were fed a diet supplemented with selenium at a subtoxic level (2.37 mg kg−1 dry matter), or the same diet without selenium supplementation (0.31 mg kg−1 dry matter), for 276 d of lactation. Copper-65, a stable isotope, was administered intravenously after 14 d of adaptation to the diets, and samples of milk, blood and liver were obtained at intervals throughout the trial. The effect of selenium supplementation on copper metabolism of the cows was evaluated by determining concentrations of copper in plasma, milk and liver, by determining the activities of ferroxidase in plasma and superoxide dismutase in erythrocytes and by determining the pattern of dilution of the copper-65 tracer in plasma, milk and liver. No effect of selenium supplementation on any of the parameters of copper metabolism was observed. It was concluded that an interaction between copper and selenium did not occur under the conditions imposed in this study. Key words: Copper, selenium, interaction, dairy cows, copper stable isotope
THE SIGNIFICANCE OF SILAGE PROTEIN DEGRADATION AND PLASMA AMINO ACID RATIOS IN THE CONTROL OF FOOD INTAKE BY LAMBS FED ENSILED AND FRESH ALFALFA
Authors: FLORES D. A. , PHILLIP L. E. , VEIRA D. M. , IVAN M.
Published: March 2010

Alfalfa (30% dry matter) was harvested with a particle length of 0.6 cm, conserved fresh (frozen) or as silage and fed to eight lambs during two 27-d periods. The ensiling process resulted in substantial degradation of lysine, threonine, histidine, arginine, tryptophan and tyrosine in the original herbage. Isoleucine, leucine and valine resisted degradation during ensilage. As a consequence of these changes, the ratios of tyrosine: large neutral amino acids and tyrosine: phenylalanine (TYR:LNAA and TYR:PHE) were markedly lower in ensiled compared to fresh alfalfa (0.035 vs. 0.051 and 0.235 vs. 0.313, respectively) but these ratios in plasma were higher (P < 0.05) with silage than with fresh forage (0.114 vs. 0.095 and 1.020 vs. 0.997). Ensiling of alfalfa resulted in a 19% reduction in silage intake but the response did not correlate with changes in plasma ratios of TYR:LNAA and TYR:PHE. Nitrogen retention was 27% lower with ensiled than with fresh alfalfa. Plasma levels of branched chain and other essential amino acids tended to be higher with fresh than ensiled forage but the difference was not significant. It is concluded that the reduction in food intake with alfalfa silage was unrelated to changes in specific ratios of amino acids in plasma but could be related to the supply of essential amino acids to the intestine of lambs. Key words: Silage intake, lambs, nitrogen balance, plasma amino acids, alfalfa
EFFECT OF DEOXYNIVALENOL (DON)-CONTAMINATED DIET FED TO GROWING-FINISHING PIGS ON THEIR PERFORMANCE AT MARKET WEIGHT, NITROGEN RETENTION AND DON EXCRETION
Authors: FRIEND D. W. , TRENHOLM H. L. , PRELUSKY D. B. , HARTIN K. E. , THOMPSON B. K.
Published: March 2010

In a feeding experiment, a total of 64 pigs (16–18 kg body weight) were assigned to four experimental diets. Three diets contained 70% wheat, one with clean wheat (C), another with DON-contaminated wheat (V) and the third a 50:50 mixture of the clean and contaminated wheats (CV). The fourth diet, included for comparative purposes only, was a barley-corn-soybean meal diet (PC). The DON content of each diet was 0.0, 0.0, 2.89 and 5.26 mg kg−1, respectively. Pigs were penned individually and offered the diets ad libitum until reaching 90 ± 5 kg body weight: a necropsy was conducted on each pig. In a metabolism trial, seven pairs of littermate barrows were fed two of the experimental diets (C and V). Feed and water allowances were based upon the voluntary intake (twice daily) of the littermate offered diet V. During a 5-d period, feces and urine were collected separately and samples taken for subsequent nitrogen and DON analyses. Pigs fed diet PC reached market weight earlier than those fed the other diets. Feed consumption and weight gain by the C and CV pigs were almost identical and these pigs averaged 9 d earlier to market weight than those fed diet V. Pigs reacted to the contaminated diets by an immediate and typical reduction of feed intake: although by the second week these feed intakes had improved, appetite and weight gain differences established in the first week persisted throughout the experiment. Increasing dietary intake of DON increased liver, kidney and uterus weights at necropsy, but the increases were not significant (P > 0.05). There was considerable variation in feed acceptance among pigs offered diet V in the metabolism trial. Those pigs rejecting diet V were not used, hence the pigs finally retained could not comprise a truly random sample. The fecal and urinary N output by pigs fed diet V was higher (P < 0.01) than that of pigs fed diet C but N retention was greater in the V pigs, due possibly to the higher N content of diet V. However, N retention as a percentage of N intake did not differ significantly between the two diets. Based upon the urinary recovery of DON and metabolite DON-1, at least 67% of the DON ingested was absorbed, a fact suggesting an explanation for the pig's sensitivity to DON. Key words: Pigs, N retention, deoxynivalenol, urinary-DON, metabolism, feeding
A LIVER BIOPSY INSTRUMENT FOR LARGE ANIMALS
Authors: BUCKLEY W. T. , EIGENDORF G. K. , DORWARD W. J.
Published: March 2010

A new liver biopsy instrument for large animals was manufactured and used to obtain samples in the range of 150–350 mg fresh weight from dairy cattle. Difficulties with the aspiration procedure caused by inadequate control of suction and excessively deep penetration of the liver were eliminated with the new instrument. Key words: Liver biopsy instrument, large animals
EVALUATION OF DIFFERENT SOURCES OF DEOXYNIVALENOL (VOMITOXIN) FED TO SWINE
Authors: FOSTER B. C. , TRENHOLM H. L. , FRIEND D. W. , HARTIN K. E. , THOMPSON B. K.
Published: March 2010

Fifty-four barrows (27.5 ± 0.5 kg) were given ad libitum for 7 wk one of 18 diets prepared from field corn inoculated with different strains of Fusarium graminearum, naturally contaminated corn and wheat, pure deoxynivalenol (DON), and clean corn. The effect of 4.7 mg pure DON kg−1 feed was not significantly different from that of the control, whereas pigs on several diets at a similar DON level had significantly lower feed intake and weight gain values. There was no correlation between DON concentration in the diets, amount ingested and pig performance. Key words: Vomitoxin, deoxynivalenol, pigs, inoculated corn, Fusarium, mycotoxins