in this study, the incomplete gamma function, an exponential function, a mixed-log function and a polynomial function were evaluated to describe the lactation curve in moroccan holstein-friesian dairy cows. data from 1990 to 1999, comprising 77130 monthly milk yields of 6029 dairy cows in 280 dairy herds, were used. edits were carried out by considering the lactation length (5 d and

In response to farmer requests after milk from their herds was rejected by processors due to poor quality, a study was carried out from April to October 2011 to determine the prevalence of sub clinical mastitis, associated risk factors and causative micro-organisms. Samples were collected from 195 dairy cows on 23 randomly selected dairy farms delivering milk to Isangano, Kirebe and Nyagatare m...

This study aimed to identify the diagnostic characteristics associated with poor prognosis and mortality in dairy cows with acute clinical Escherichia coli mastitis. On 17 dairy farms, 24 dairy cows with acute E. coli mastitis that had received therapeutic treatment were categorized into 2 groups by outcome: 17 cows that recovered (survivors) and 7 cows that died or were euthanized (non-survivo...

The primary objective was to compare reported antimicrobial usage between conventional and organic dairy farms. A secondary objective was to contrast selected management characteristics of conventional and organic dairy herds. A questionnaire was administered on site to selected dairy farmers located in Michigan, Minnesota, New York, and Wisconsin. Organic herds (n = 32) were smaller and produc...

The aim of this study was to evaluate the effect of the season (ambient temperature and relative humidity) on some blood metabolites in dairy cows during postpartum period. Blood samples were collected from 195 clinically healthy dairy cows of 8 Italian dairy herds in spring (April-May 15.5±4 °C and 69.5±0.7 %), summer (June-July 23±1.5 °C and 69±1.3 %) and autumn (September-October 17±2 °C and...

hemorrhagic bowel syndrome is a highly fatal intestinal disease of adult dairy cattle with uncertain cause. in a dairy herd in khorasanrazavi province, northeast of iran, two cows showed depression, anorexia, decrease in milk production, ruminal hypomotility, bruxism and dehydration. at necropsy, massive hemorrhage and clot formation was observed within the jejunum and bacterial culture of the ...

Immune function in cows is closely associated with their physical and hormonal conditions. In order to clarify the relationship between the body condition score (BCS) of lactating dairy cows and the immune response to progesterone (P(4)) in vitro, we examined whether lower BCS in dairy cows affects the responsiveness of peripheral blood mononuclear cells (PBMCs) to P(4) added in to culture medi...

Leitner, G. 162 INTRODUCTION Economic pressure drives modern dairy farmers to exert continuous efforts to maximize profitability. This is achieved by constant improvement of genetic selection, nutrition, and herd management. Modern dairy farms are characterized by high levels of computerized data acquisition, which provides on-line information on cows' milk yield, milk composition and body weig...

The objectives of this study were to relate concentrations of plasma (PUN) and milk (MUN) urea nitrogen to pregnancy rate in dairy cows and compare various methods of analysis and preparation of milk for measuring MUN. In two experiments, blood or milk samples were collected on the day of AI from Holstein cows (n = 160 and n = 155, respectively). Three methods of MUN analysis were compared. Two...

BACKGROUND Uterine disorders are common postpartum diseases in dairy cows. In practice, uterine treatment is often based on systemic or locally applied antimicrobials with no previous identification of pathogens. Accurate on-farm diagnostics are not available, and routine testing is time-consuming and cost intensive. An accurate method that could simplify the identification of uterine pathogeni...