The objective of this study was to investigate the effect of feeding different levels of ruminally protected methionine and choline on the incidence of physiological and metabolic disorders, production, and some of the reproductive indices of Holstein dairy cows. Forty Holstein dairy cows in their first and second lactation were ...

Cow gait, walking speed, time spent lying down, and distribution of weight among legs when standing during the week before and up to 5 wk after hoof trimming were assessed in 48 lactating Holstein cows housed in freestall pens to examine how changes in gait score following hoof trimming were ...

An experiment was conducted to measure the effect of diet on circulating concentrations of metabolic hormones and metabolites in cows undergoing extended lactations. Two groups of 6 Holstein-Friesian cows managed for lactations of 670 d were used in the experiment. One group was fully fed on a total mixed ration ...

The primary objective of our research was to determine the effect of a high dose of monensin supplementation on enteric CH(4) emissions of dairy cows offered a ryegrass pasture diet supplemented with grain. An additional objective was to evaluate effects on milk production and rumen function, because a commensurate improvement ...

Feeding dairy cows large proportions of cereal grain is commonly associated with rumen acidosis, activation of innate immunity, and perturbation of intermediary metabolism. We previously showed that steeping barley grain in 0.5% lactic acid (LA) decreased the rate of starch degradation, lowered the risk of subacute rumen acidosis, modulated rumen ...

The objective of this study was to determine the contribution of cow factors to the probability of a successful first insemination (SFI). The investigation was performed with 51,791 lactations from 1,396 herds obtained from the Dutch dairy cow database of the Cattle Improvement Co-operative (CRV). Cows that had the first ...

The objective of this study was to examine the effects of live yeast (LY) supplementation and body condition score (BCS, 1-5 scale) at calving on milk production, metabolic status, and rumen physiology of postpartum (PP) dairy cows. Forty Holstein-Friesian dairy cows were randomly allocated to a 2 × 2 factorial ...

Studies investigating variation in birth sex ratio indicate that the energy status of the dam prebreeding can influence the sex of the subsequent offspring. The Trivers-Willard hypothesis suggests that dams in good condition would produce more male offspring, whereas dams in poor condition (relative to dams in good condition) would ...

Our objectives were to determine if dietary cation-anion difference (DCAD) and source of anions influence periparturient feed intake and milk production of dairy cattle during the transition period. Diets differed in DCAD (cationic or anionic) and anionic supplement. The 4 diets used prepartum were (1) control [DCAD +20 mEq/100g of ...

To evaluate the effects of calcium propionate (CaP) supplementation on feed intake, milk yield and milk composition, energy balance, blood metabolites and urine ketones in early lactation Holstein dairy cows from 1 to 63 days in milk (DIM), 32 multiparous Holstein dairy cows, blocked by lactation number, previous 305-day milk ...

A compensatory finishing strategy was evaluated to improve the quality of meat from dairy cows. The experiment included ten pairs of Holstein Friesian dairy cows. Each pair was the progeny of the same sire, in the same parity, and approximately at the same number of days in lactation before entering ...

A total of 1,243 records for 585 dairy Friesian cows from 1997-2004 were used to study the factors affecting dystocia and its effects on reproductive performance and milk production. The overall incidence of dystocia was 6.9%. The percentage of dystocia decreased with increasing live body weight, age, and parity of ...

This study evaluated potential effects of organic trace mineral supplementation on reproductive measures in lactating dairy cows. Cows were blocked by breed and randomly assigned at dry-off to receive inorganic trace mineral supplementation (control; n = 32) or to have a portion of supplemental inorganic Zn, Cu, Mn, and Co ...

The objective of this study was to investigate the effect of dietary supplementation with the disaccharides trehalose and cellobiose on antioxidant activity in rumen fluid, blood, and milk of dairy cows. Nine Holstein dairy cows housed in a free-stall barn were divided into 3 groups, with each group receiving a ...

Numerous adjunct therapeutic agents have been investigated for the treatment or control of fat mobilization syndrome in periparturient dairy cows. The aim of this study was to determine the effects of multiple i.v. injections of 10% butaphosphan and 0.005% cyanocobalamin combination (Catosal, Bayer Animal Health, Leverkusen, Germany) between 1 and ...

The objective of the study was to quantify the effect of genetic improvement using the Irish total merit index, the Economic Breeding Index (EBI), on overall performance and lactation profiles for milk, milk solids, body weight (BW), and body condition score (BCS) within 2 pasture-based systems of milk production likely ...

Feed intake and feeding behavior of dairy cows fed diets that varied in fat supplementation and forage:concentrate (F:C) ratio were investigated. Eight multiparous Holstein dairy cows were used in a replicated 4x4 Latin square experiment with 21-d periods. Treatments were 1) no supplemental fat and 34:66 F:C ratio; 2) 2% ...

The working hypothesis was that postpartum anovulatory intervals (PPAI) of grazing dairy cows are shortened by inclusion of concentrates that increase the nonstructural carbohydrate content of the transition diet. Dietary treatments were arranged as a 2x2 factorial, with 68 multiparous cows assigned to isoenergetic diets (114 MJ of metabolizable energy/cow ...

The primary objective of the study was to quantify the effect of genetic improvement using the Irish total merit index (Economic Breeding Index) on dry matter intake and feed efficiency across lactation and to quantify the variation in performance among alternative definitions of feed efficiency. Three genotypes of Holstein-Friesian dairy ...

The objective of this study was to evaluate the effects of claw horn disruption lesions (CHDL; sole ulcers and white line disease) and body condition score (BCS) at dry-off on survivability, milk production, and reproductive performance during the subsequent lactation. An observational prospective cohort study was conducted on a large ...

The hypothesis was that dairy cows housed for 1 mo after calving in a separate group with herd mates would produce more milk and would be healthier than cows integrated in a group of all lactating cows immediately after calving. The experiment was conducted with 489 cows in 6 commercial ...

Methodological problems occur in measuring herbage intake and diet quality during short-term (4-24h) progressive defoliations by grazing. Several models were developed to describe pasture component selection by grazing ruminants, particularly sheep. These models contain empirical coefficients to determine preferences that require laborious and data-demanding calibration. The objective was to develop ...

Multiparous Israeli-Holstein cows (n=42) averaging 158 d in milk and 621 kg of body weight were used to investigate the effects of energy source (fat or concentrate) on production, rumination time, energy balance, metabolic heat production, and efficiency under hot and humid conditions. Cows were assigned to 3 diet treatment ...

An experiment was conducted to determine the effect of plane of energy intake prepartum on postpartum performance. Primiparous (n=24) and multiparous (n=23) Holsteins were randomly assigned by expected date of parturition to 1 of 3 prepartum energy intakes. A moderate energy diet [1.63 Mcal of net energy for lactation (NE(L))/kg; ...

The objective of this study was to investigate serum lipids, metabolic parameters and activity of the anti-oxidative enzyme paraoxonase-1 (PON1). The study was conducted on non-pregnant heifers with optimal health status and on healthy dairy cows in the period of intensive lactation, assuming that the energy and metabolic demands during ...

Objectives of the present study were to evaluate the effects of supplementation of bypass fat on milk production and reproductive performance of crossbred cows. Nineteen multiparous crossbred cows (2-4 lactation) were divided in two groups on the basis of most probable production ability (MPPA). The animals in group 1 (nine ...

The objective of this experiment was to investigate the effect of fat supplementation during the transition period on pre and postpartum body weight (BW), body condition score (BCS), non-esterified fatty acids (NEFA), glucose and leptin concentrations in Holstein cows. Holstein cows (n = 15) received a low fat diet (LF; ...

Heat stress of lactating cattle results in dramatic reductions in dry matter intake (DMI). As a result, energy input cannot satisfy energy needs and thus accelerates body fat mobilization. Decreasing the level of roughage neutral detergent fiber (NDF) in prepartum diets, and thereby increasing the amount of nonfiber carbohydrates, may ...

Four US genetic-economic indices for dairy cattle were retrofitted to illustrate differences in phenotypic response observed for retrospective selection over 2 generations for currently evaluated traits, even though producers did not have evaluations available at the time for direct selection for those traits. Differences among cows were compared based on ...

The objective was to determine the effects of natural- or synthetic-source vitamin E on reproductive efficiency in Angus-cross beef cows. In Exp. 1, one hundred fifty-two cows were fed hay and corn silage based diet and assigned to 1 of 3 dietary supplements (3 pens/treatment): 1) containing no additional vitamin ...

This study compared three methods of estrus detection and characteristics of standing estrus between dairy cows kept in cubicle housing and fed a total mixed ration diet (HOUSED treatment) and those kept at pasture with concentrate ration supplementation (PASTURE treatment). The 23 spring-calved Holstein-Friesians in each treatment were monitored by ...

Mature Angus-cross beef cows (n = 144) were used to determine effects of late gestation dietary energy source on pre- and postpartum cow performance in a complete randomized block design experiment. Cows were adapted to diets starting at 167 +/- 9 d of gestation and fed until 1 wk before ...

The purpose of this study was to test whether supplementation with K improves bone mineral density (BMD) in older cows so that by parturition their bone is better able to mobilize Ca. Twenty-four Holstein Friesian cows (6 mo pregnant, lactating, and in their third or later lactation) were allocated to ...

The present experiment was undertaken to study the interactions between dietary supplements of rumen-protected methionine (RPM) and intramuscular injections of folic acid and vitamin B(12), given from 3 wk before calving to 16 wk of lactation, on hepatic metabolism of lactating dairy cows. Sixty multiparous Holstein cows were assigned to ...

How hair-coated animals such as dairy cows synthesize endogenous vitamin D(3) during exposure to summer sunlight has been unclear since vitamin D(3) and its relation to sunlight was discovered. The fur of fur-bearing animals is thought to be comparable to clothing in humans, which prevents vitamin D(3) synthesis in the ...

Capturing urine and spreading it evenly across a paddock reduces the risk of nitrogen loss to the environment. This study investigated the effect of 16h/d removal from pasture on the capture of urination events, milk production, pasture intake, and animal welfare from cows grazing fresh pasture in early and late ...

Favorable uterine involution and ovarian activity are very important for the next reproductive cycle of postpartum cows. The objective of this study was to evaluate the effect of parity on uterine involution and resumption of ovarian activity in Chinese Holstein dairy cows after calving under similar postpartum nutritional conditions. Traits ...

Decreased milk production of beef cattle grazing endophyte-infected (EI) tall fescue (TF), an important cool season grass in the southeastern United States, can affect calf growth. The objective was to determine whether a thermal or heat-tolerant Bos taurus breed of cattle, Romosinuano (RO), would tolerate EI TF toxins relative to ...

The objectives were to evaluate effects of maternal nutrient restriction and stage of gestation on maternal and fetal visceral organ mass and indices of jejunal growth and vascularity in beef cows. Thirty multiparous beef cows (BW = 571 +/- 63 kg; BCS = 5.4 +/- 0.7) carrying female fetuses (d ...

The aim was to evaluate the effect of corn oil supplementation during postpartum anoestrus on ovarian activity, pregnancy rate, progesterone (P(4)), and lipid metabolites (cholesterol, CHO; low and high density lipoproteins; LDL and HDL, respectively) concentrations in blood of F(1) (Bos taurus x Bos indicus) grazing cows. Cows were randomly ...

The objectives of this study were to quantify the effect of 16 ppm of dietary monensin on milk production and composition of dairy cows, and to investigate factors having a potential impact on this effect. Data were generated from a total of 3577 Holstein dairy cows (47 herds) in Quebec ...

A significant proportion of cattle receive inadequate dietary Se because of its low content in soils and pastures of various regions of the world. Several economically important diseases in dairy cows, such as mastitis, have been associated with Se deficiency. The objective of this study was to evaluate the effect ...

OBJECTIVE: To evaluate the effect of the number of days exposure to a prepartum transition diet on mineral, energy and protein metabolism in dairy cows. DESIGN: A prospective cohort study. PROCEDURES: The prepartum transition diet consisted of ryegrass pasture, cereal hay, grain, grain by-product, protein meals, BioChlor, rumen modifiers, minerals ...

Two groups of five crossbred 87.5% Holstein cattle were housed in normal shade only (NS) as non-cooled cows and in shaded housing with misty-fan cooling (MF) as cooled cows. The cows were treated with recombinant bovine somatotropin (rbST) in early, mid and late lactation with three consecutive injections of rbST ...

Elevated rates of steroid clearance may lead to lower reproductive success in several mammalian species. Cytochrome P450 (EC 1.14.14.1) and aldo-keto reductases (AKR; EC 1.1.1.145-151) are involved in the first phase of steroid inactivation, before second phase conjugation and excretion of the steroid metabolite. The current objectives were to determine ...

In the cow, inadequate concentrations of progesterone during gestation may lead to an abrupt termination of pregnancy. The primary organ involved in progesterone catabolism is the liver, which contains an abundance of cytochrome P450 isozymes (EC 1.14.14.1; mixed-function monooxygenases). The objectives of the current experiment were to determine the effect ...

This study was conducted to determine whether extending the calving interval (CI) to 24 mo would be an alternative to culling and replacing cows that had failed to become pregnant. Forty-six nonpregnant lactating cows were assembled in November 2004 and assigned to receive either 3kg (low) or 6kg (high) of ...

The objective of this experiment was to determine if duration of daily bull exposure influences length of postpartum anestrus in primiparous, anovular, suckled, beef cows. The null hypotheses were that intervals from calving or the start of bull exposure (D 0) to resumption of ovulatory activity (OA), and proportions of ...

OBJECTIVE: To evaluate the effect of the number of days exposure to a prepartum transition diet on reproduction and health in dairy cows. DESIGN: A prospective cohort study. PROCEDURES: We enrolled 1008 dairy cows from three herds to examine the effects on reproduction and health of increased days exposure to ...

Reproduction and milk production responses were compared between dairy cows offered a high (HPA; n=453 in 4 replicates) or low (LPA; n=317 in 3 replicates) pasture allowance for the first 14 d after the planned start of mating (d 0 of experiment) in 2 seasonal, pasture-based dairy herds. Estimated pasture ...