Nutrition has an important impact on the reproductive performance of dairy cattle. Energy is the major nutrient required by adult cattle, and inadequate energy intake has a detrimental impact on reproductive activity of the female bovine. Cows under negative energy balance have extended periods of anovulation. Postpartum anestrus, as well as infertility, is magnified by losses of body condition...

This study tested the hypothesis that the increased glucose requirement of lactation had effects that were independent of the suckling-dependent inhibition of postpartum endocrine function in beef cows. Mature Hereford cows were either suckled ad libitum and infused with saline iv (n -9) from d 2 through 4 (d 0 = jugular catherization on d 32 -+ 3 postpartum); were nonsuckled and infused with s...

The effect of parity (multiparous vs primiparous) and body condition score (BCS; <3.0 or > or =3.0, lean vs fat) at parturition on metabolic and endocrine profiles from 1 month before to 2 months after parturition were studied in 42 Holstein cows grazing on improved pastures. BCS and milk production were determined every 2 weeks. Non-esterified fatty acids (NEFA), beta-hydroxy-butyrate (BHB), i...

Postpartum endometritis compromises milk production and fertility in high-producing dairy cows. Infection of the endometrium induces an inflammatory response with secretion of cytokines that lead to polymorphonuclear cells (PMN) influx and bacterial clearance. Considering that only a portion of cows with endometritis is eligible for clinical diagnosis, there is an increasing effort for developi...

the objective of this study was to determine the effect of calcium borogluconate injection 48 and 24 hours prepartum and immediately after parturition on dry matter intake at day of calving, milk yield, incidence of metabolic disorders and uterine conditions during the first 21 days postpartum in cows fed anionic diets. thirty six lactating dairy cows were balanced by parity (1, 2, 3+) and allo...

Gestating Angus, nonlactating, spring-calving cows were used to determine variation in maintenance energy requirements (MR); to evaluate the relationship among MR and cow and calf performance, plasma concentrations of IGF-I, T4, glucose, insulin, and ruminal temperature; and to describe the LM proteome and evaluate protein abundance in cows with different MR. Cows (4 to 7 yr of age) with a BCS ...

The objective was to investigate the effect of different dry cow feeding strategies on the degree of ketonemia postpartum. Epidemiologic studies provide evidence of an association between elevated β-hydroxybutyrate (BHBA) concentrations in postpartum dairy cows and a decreased risk for reproductive success as well as increased risk for several diseases in early lactation, such as displacement o...

This study investigated the effects of rumen-protected methionine (RPM) and rumen-protected choline (RPC) on energy balance, postpartum lactation performance, antioxidant capacity and immune response in transition dairy cows. Forty-eight multiparous transition cows were matched and divided into four groups: control, 15 g/d RPC, 15 g/d RPM or 15 g/d RPC + 15 g/d RPM. Diet samples were collected ...

This study explored the effects of a single administration of flunixin meglumine (acting as a non-steroidal antiinflammatory drug) and oxytetracycline combination on the reproductive performance of cows diagnosed with subclinical endometritis during the postpartum period. Cows aged 3 to 9 at 40 to 60 days postpartum were studied. Endometrial samples were collected from cows that had a uterine c...

Two experiments were conducted with lactating Angus x Gelbvieh beef cows to determine the effects of postpartum lipid supplementation, BCS at parturition, and day of lactation on fatty acid profiles in plasma, adipose tissue, and milk. In Exp. 1, 36 pri-miparous cows (488 +/- 10 kg of initial BW; 5.5 +/- 0.02 initial BCS) were given ad libitum access to hay and assigned randomly to a low-fat (c...