Twenty-four Holstein cows were used to study the effect of dietary fat on milk production and metabolic traits. Whole cottonseed and tallow were used as fat sources and substituted into the control diet on an isocaloric basis. Chopped alfalfa hay and grain sorghum silage constituted the forage in all diets. Treatments were balanced for parity, body weight, and previous lactation milk production...

Postpartum cows (n=25) were assigned randomly to receive an intramuscular injection of gonadotropin releasing hormone (GnRH; 100 /~g) at either 3, 10, 20, 30 or 40 days postpartum (five cows per group). Blood samples were collected via jugular catheter at lO-min intervals from 3 0 to +180 rain and at 30-min intervals from +180 to +420 min after GnRH. Plasma levels of luteinizing hormone (LH), e...

In early postpartum, high-producing dairy cows undergo a period of extensive tissue catabolism because of negative nutrient balance. Metabolic unbalances can lead to diseases, which are known to depress fertility in dairy cows. Negative nutrient balance has been associated with compromised immune and reproductive functions in dairy cows, and a compromised immune system leads to greater risk of ...

The aim of the present study was to show the distribution of cows by days in milk (DIM) at first AI, effect of DIM at first AI on reproductive performance and some factors influencing DIM at first AI. A total of 767 Holstein Frisian cows that calved from January 2004 to December 2007 in 14 dairy herds were used. The first AI conception rate (FAICR) was 34.0%. Seventy-five percent of the cows we...

This study was carried out at the Livestock Experiment Station, Bhunikey (Pattoki), District Kasur, Pakistan. Forty exotic cows (20 each of Holstein Friesian and Jersey breed) in their last trimester of pregnancy were randomly selected. These cows were divided into two equal groups. Animals of group-I served as control and were injected with 20 ml sterile normal saline intramuscularly, while ea...

BACKGROUND Laminitis and energy-related postpartum diseases share several risk factors, indicating a common etiology. Thus, a herd's incidence rate of energy-related postpartum diseases, such as displaced abomasum and clinical ketosis, might reflect the likelihood of cows to suffer from laminitis-related claw lesions. The aim of this study was to investigate the association between herd-level i...

A total of 65 multiparous cows that calved during the hot season (n = 21), temperate season (n = 23) or cold season (n = 21) were used to investigate the relationships between heat stress, seasonal changes, metabolic traits, body condition score (BCS), resumption of ovulation and occurrence of subclinical endometritis (SE). Cows were monitored for the first 7 weeks of lactation by ultrasonograp...

The effect of different feeding intensity at two stages of gestation on performance of primiparous cows was studied in 40 pregnant Ayrshire cows. The feeding intensity was either medium (M) or high (H) in period 1 (2–6 months of pregnancy) or period 2 (7–9 months of pregnancy) resulting in treatments MM, MH, HM and HH. Before pregnancy all heifers were reared to gain 650 g/day. In period 1, hei...

The purpose of the study was to evaluate the effect of retained fetal membranes (RFM) on serum minerals and energy- and protein-related metabolites in dairy cows at a herd with a recent history of fatty liver syndrome. Forty-seven multiparous Holstein cows were selected during transition period. Nine cows had RFM longer than 24 h after calving. Blood samples were obtained on prepartum days 21 a...

Hepatic metabolic gene networks were studied in dairy cattle fed control (CON, 1.34 Mcal/kg) or higher energy (overfed (OVE), 1.62 Mcal/kg) diets during the last 45 days of pregnancy. A total of 57 target genes encompassing PPARα-targets/co-regulators, hepatokines, growth hormone (GH)/insulin-like growth factor 1 (IGF-1) axis, lipogenesis, and lipoprotein metabolism were evaluated on -14, 7, 14...