Four treatments were assigned to determine the effects of dietary potential digestible fiber (pdF) and crude protein (CP) levels in mid lactating Holstein cows on milk production and nitrogen efficiency. Sixteen primiparous (n=8) and multiparous (n=8) Holstein cows (body weight (BW)=546±72 kg; days in milk (DIM)=118±50 day) were allocated to one of four diets in balanced randomized complete des...

The objective of the study was to assess the effects of intravenous infusion of triacylglycerol (TAG) emulsions derived from different lipid sources on responses to mitogens of peripheral blood mononuclear cells (PBMC) isolated from fasted dairy cows. Six multiparous, non-pregnant, non-lactating Holstein cows were used in a replicated 3x3 Latin Square design. For 4 d, cows were fasted and infus...

The aim of this study was to investigate the effect of diets containing roasted soybean (R), extruded soybean (E) or their combination (RE) on dairy cow performance and milk fatty acid (FA) profile. Nine multiparous lactating Holstein cows (680 ± 25 kg BW; 90 ± 10 DIM; means ± SD) were randomly assigned to a triple 3 × 3 Latin square design. Dry matter intake (DMI), apparent nutrient dige...

Early weaning is used to advance postpartum ovulation in beef cows, but triggers a stress response, affecting cows' and calves' welfare. Our aim was to compare the response to early weaning in multiparous and primiparous cows. Seventy-one days after birth, calves from 14 primiparous and 11 multiparous cows were weaned. Since birth, cow's body weight (BW), body condition (BC), milk yield and cal...

A high incidence (about 70%) of alteration in endometrial epidermal growth factor (EGF) profile, i.e., loss of 2 peaks on days 2-4 and 13-14, has been linked to a reduced fertility in multiparous repeat breeder Holstein cows. However, the EGF profile in Holstein heifers and other breeds (types) of cattle has not been investigated. In study 1, EGF concentrations were determined using endometrial...

Two experiments were conducted to evaluate dry matter intake (DMI), milk yield, and milk composition from feeding rations that contained different sources of genetically modified whole cottonseed to Argentinean Holstein dairy cows. Twenty-four lactating multiparous Argentinean Holstein dairy cows were used in 2 experiments with a replicated 4 x 4 Latin square design, with cows averaging 565 kg ...

Three corn hybrids harvested as whole-plant silage were evaluated in three separate feeding trials with lactating dairy cows. In trial 1, 24 multiparous Holstein cows were used in a replicated 4 x 4 Latin square with 28-d periods. Treatments were conventional (Pioneer 3563) and leafy (Mycogen TMF 106) corn silage hybrids, each planted at low (59,000 plants/ha) and high (79,000 plants/ha) plant ...

To determine the effects of dry period (DP) length on milk yield, milk composition, some blood metabolites, complete blood count (CBC), body weight and score and follicular status, twenty five primiparous and multiparous Holstein cows were assigned to a completely randomized design with DP-60 (n = 13) and DP-20 (n = 12) dry period lengths. Cows in the DP-60 produced more milk, protein, SNF, ser...

To compare 2 strategies for systematically resynchronizing ovulation, lactating Holstein cows (n = 763) at various days in milk and prior artificial insemination services were assigned randomly at timed AI (TAI) to receive the first GnRH injection of Ovsynch 26 (D26) or 33 (D33) d after TAI to resynchronize ovulation (Resynch) in cows failing to conceive. Cows in the D26 treatment received GnRH...

Recombinant bovine somatotropin (rBST) changes metabolism to spare glucose for milk synthesis in cows. Ceramides inhibit insulin responsiveness adipocytes and are associated with resistance production The mechanisms by which rBST supports lactation may involve ceramide. Eight multiparous lactating Holstein cows were enrolled a 2 × replicated Latin square design 14-d periods. Cows received singl...