Showing papers in "Journal of Dairy Science in 1983"

TL;DR: The o-phthaldialdehyde Spectrophotometric (OPS) as discussed by the authors was developed and characterized for measurement of proteolysis of milk proteins in buffered solutions or in milk.

TL;DR: Clinical problems at parturition and postpartum lowered reproductive performance in both breeds and there was a slight antagonism between milk yield and reproductive performance (days open) in Jerseys but not in Holsteins.

TL;DR: Mixed rumen bacteria were incubated in media containing salts, ammonia, vitamins, volatile fatty acids, sulfide, and casein, and Nitrogen-15 labeling studies indicated that 66% of the cell nitrogen was derived directly from casein at all rates of carbohydrate addition.

TL;DR: Sperm transport has been improved by adding to semen or administering to females such compounds as prostaglandin F2 alpha, oxytocin, estradiol, phenylephrine, or ergonovine, which increased fertilization rates.

TL;DR: Improved digestion of lactose was not due to hydrolysis of the lactose prior to consumption, which indicated that the beneficial effect must have occurred in the digestive tract after consumption of milk containing L. acidophilus.

TL;DR: Plasmin and plasminogen-derived activities were measured in bovine and human skim milk with a chromogenic tripeptide H-D-valyl-L-leucyl-L -lysine-p-nitroanilide substrate.

TL;DR: In this paper, the authors obtained measures of yield and fertility from breeding receipts of artificial insemination and records of test-day yield, using the Henderson Method 3, maximum likelihood, and restricted maximum likelihood.

TL;DR: Daily administration of growth hormone in early or late lactation resulted in similar and substantial increases of milk yield and efficiency of milk production.

TL;DR: The crude protein content of the diet altered concentrations in blood of ammonia and concentrations in plasma of urea, phosphorus, potassium, and zinc, and the effects of dietary crude proteins on constituents of plasma and uterine secretions were examined at various stages of the estrous cycle of high producing Holstein cows.

TL;DR: Major factors determining water consumption in early lactation have been identified and quantitated and Regression coefficients for milk production and sodium intake agreed with literature estimates.

TL;DR: Data of 22,691 observations on parturition related problems (dystocia, calf mortality, milk fever, retained placenta, and mastitis) were collected from 27 cooperating California dairy herds and decided on breeding virgin heifers based on size of cow because of the effect of size ofcow on difficulty at first parity.

TL;DR: The incidence of udder infection was highest in cows completing third or later dry periods, whereas Corynebacterium bovis infected quarters decreased and coagulase negative staphylococcal infections increased during the dry period.

TL;DR: First lactations from a total of 5802 cows in the North Carolina Institutional Breeding project from 1950 to 1980 were used and heritabilities and variance of sires increased for days open and yield traits from the 1950's to 1980.

TL;DR: Aseptic foremilk samples were collected biweekly for four samplings and then monthly throughout lactation from 35 does in three herds on Dairy Herd Improvement test, and coagulase negative staphylococci were the most frequent isolates.

TL;DR: The negative influence of excess feeding on mammary development of prepubertal heifers may be associated with a decrease in concentrations of growth hormone in blood.

TL;DR: Effects of stage of lactation and parity on cell concentration, electrical conductivity, and serum albumin concentration of milk from quarters of known infection status were examined.

TL;DR: A large population of ciliates was associated with increases in both rumen ammonia and plasma urea but had a stabilizing effect on ruminal pH, and effects of ciliate protozoa are related to animal performance.

TL;DR: In this article, the rate and extent of neutral detergent fiber degradation were determined for 22 feedstuffs in situ, and two diets were formulated to be similar in chemical composition but to differ in fill.

TL;DR: The casein-based proteins, particularly sodium caseinate, produced yogurts that were generally inferior to gelatin for smoothness and appearance, and Whey protein concentrates, at 1.0 and 1.5% of protein addition, produced Yogurts generally superior to caseIn-based products for both appearance and smoothness.

TL;DR: Of the thresholds examined, 1000 X 10(3) cells/ml was most satisfactory for both Coulter Counter and Fossomatic methods, because it detected about 80% of major infections and gave an acceptable proportion of errors.

TL;DR: This experiment shows colostral immunoglobulin concentration is a major factor in the rate of immunoglobeulin absorption and the amount of absorption when it is fed to newborn calves, and when compared on equal mass, the amountof colostrum fed, 1 or 2 liters, had less influence on immunoglOBulin absorbed than did concentration.

TL;DR: The prepubertal period, which starts at 10 to 12 wk in well-fed Holstein bulls, is characterized by profound changes of hypothalamic, pituitary, and gonadal function that culminate in puberty.

TL;DR: The results suggest a gradual effect on chemical degradation and physical detrition of digesta particles and chewing behavior as forage particle size decreased.

TL;DR: In this paper, the effects of salt concentration, aging time, and tempering time after thawing on characteristics of part-skim Mozzarella cheese were evaluated using compression, beam bending, and sensory evaluation (salt intensity, aged flavor, firmness, cohesiveness and fibrousness).

TL;DR: The number and type of primary pathogen infections during early lactation were similar to those at parturition, and the number of coagulase negative staphylococcal infections decreased markedly.

TL;DR: A combination of heated soybean meal to limit rumen degradability and ammonia in corn silage to furnish nonprotein nitrogen was the most productive and profitable of several rations compared for cows early in lactation.

TL;DR: Blood and colostrum samples were obtained from 87 dairy cows in five lactation groups and analyzed for immunoglobulins G1, G2, M, and A.

TL;DR: Yogurts prepared with three types of commercial whey protein concentrate were similar in structure but differed distinctively from casein-based yogurts in that casein micelles were individual in nature with intermicellar spaces spanned with flocculated protein.

TL;DR: In this article, the effects of forage intake and particle length on chewing time were investigated, and it was shown that total chewing time was associated with mean particle length of the consumed forage.

TL;DR: Daily milk production near estrus was associated with longer duration between heats but had no effect on conception and lactation number and service number were related to fertility.