This study aimed to investigate the effects of insulin resistance (IR) during the close-up dry period on the metabolic status and performance of dairy cows as well as to determine the effects on body weight (BW) and metabolic status of their calves. An insulin tolerance test (ITT) was conducted by administering 0.05 IU/kg BW of insulin to 34 multiparous Holstein cows at 3 weeks prepartum. Blood...

From birth to the time after weaning the gastrointestinal microbiota of calves must develop into a stable, autochthonous community accompanied by pivotal changes of anatomy and physiology of the gastrointestinal tract. The aim of this pilot study was to examine the fecal microbiota of six Simmental dairy calves to investigate time-dependent dynamics of the microbial community. Calves were follo...

The longstanding assumption that calves of more than 6 months of age are more resistant to Mycobacterium avium subspecies paratuberculosis (MAP) infection has recently been challenged. In order to elucidate this, a challenge experiment was performed to evaluate age- and dose-dependent susceptibility to MAP infection in dairy calves. Fifty-six calves from MAP-negative dams were randomly allocate...

BACKGROUND Dehorning is a common practice involving calves on dairy operations in the United States. However, less than 20% of producers report using analgesics or anesthetics during dehorning. Administration of a systemic analgesic drug at the time of dehorning may be attractive to dairy producers since cornual nerve blocks require 10 - 15 min to take effect and only provide pain relief for a ...

Problem statement: Imported Holstein Friesian dairy cattle are exposed to hot arid climate in feedlot management in Kuwait. Desert climate is extreme reaching high 45-50°C in summer and low -4oC in winter at day and night respectively. High calf mortality, poor reproduction and milk yields were main constraints to viable dairying. The objectives of this study were to assess the magnitude of cal...

the clinical features of salmonellosis and prevalence of salmonella serogroups in calves were studied on one hundred and thirty two suspected calves in dairy farms around tehran. clinical examinations were carried out and the faecal or tissue (if calve was euthanized or dead) samples were collected for bacterial culture. the results were analyzed with chi-square statistical test. salmonella spp...

BACKGROUND Milk produced by cows in receipt of antimicrobial therapy may contain antimicrobial residues. Such antimicrobial-containing waste milk must be withdrawn from human consumption and is therefore sometimes used as calf feed. Unfortunately, this approach might promote selection of antimicrobial resistant bacteria in the calves' intestinal microbiota. The objectives of this study were the...

this experiment was conducted to determine the effect of feeding alfalfa hay and starter fiber level on feed intake and performance of holstein dairy calves, using thirty two male calves in a completely randomized design assigned to four diets in a 2×2 factorial arrangement. the experimental treatments were as follow: t1: starter with low fiber and without alfalfa hay, t2: starter with low fibe...

Dairy calf death rates from birth to weaning approximate 8 to 10% in the US. Stillbirths on dairies, measured as calves dead at delivery or within the first 24 to 48 hours after delivery, are less closely monitored, but are estimated between 6 and 12%. Numerous factors influence calf health and survival, but the key contributors to calf morbidity and mortality can be managed to greatly reduce t...

In a national survey of dairy operations with > or = 30 milking cows, fecal samples from 6861 preweaned dairy heifer calves on 1063 operations were tested for Salmonella. One hundred forty-five (2.1%) of the fecal samples from 79 (7.4%) of the farms tested positive for Salmonella. A multivariate logistic regression model revealed that medicated milk replacer and hay fed to dairy heifers from 24...