Effects of seven breeds of cow's sire and 12 breeds of cow's maternal grandsire on preweaning performance of crossbred cows and their calves were examined in data from two experiments conducted at the Roman L. Hruska U.S. Mean Animal Research Center. Data included 1,836 records over three to five parities for 516 cows by 143 sires and by 307 maternal grandsires. The statistical model fitted eff...

Objective was to determine the influence of breed and quantity of milk replacer fed on the performance of dairy calves. Forty-two bull calves (n = 20 Holstein and n = 22 Jersey, 2 ± 1 d old) in a 2 × 2 factorial arrangement were observed through 11 weeks of age. Holstein and Jersey calves on the lower plane of nutrition were fed a 20% protein and 20% fat milk replacer at a rate of 454 g / d. Ho...

Forty-eight Holstein bull calves were assigned to a 2 x 2 x 2 factorial arrangement in a completely randomized block design. Main effects were colostrum versus a serum-derived colostrum supplement, 0 versus 1 g of trypsin inhibitor added at the initial 2 feedings, and milk replacer containing 0 or 50% CP from whole egg. Calves were bled at 0, 6, 12, 18, and 24 h after birth for determination of...

BACKGROUND The prevention of bovine respiratory disease complex (BRD) in beef cattle is important to maintaining health and productivity of calves in feeding operations. OBJECTIVE Determine whether BRD bacterial and viral pathogens are susceptible to the lactoperoxidase/hydrogen peroxide/iodide (LPO/H2 O2 /I- ) system in vitro and to determine whether the oral administration of sodium iodide ...

Urea is an important reutilizable nitrogen source for the ruminant and is mainly synthesized through the urea cycle in the liver. The cycle is undertaken by 5 enzymes: carbamoyl phosphate synthetase (CPS), ornithine transcarbamoylase (OTC), arginino-succinate synthetase (AS), argininosuccinate lyase (AL), and arginase. The purpose of this study was to investigate changes in the activity of the ...

The present study was carried out to evaluate the effect of supplementation exogenous fibrolytic enzymes (EFE) on voluntary feed intake, availability different nutrients and growth performance in weaned crossbred calves. Fifteen healthy female Jersey calves (weight 79.73±3.46 kg; age 234.5±11.33 days) were divided equally into three groups viz., Control (T0), Treatment-1 (T1) Treatment-2 (T2). ...

Newly arrived feedlot calves undergo numerous stressors that result in 1) transient endocrine responses, 2) altered products of energy and protein metabolism, 3) changes in appetite and growth rate, 4) possible limited compromise of digestive and rumen function, and 5) a challenged immune system. The most consistent endocrine and metabolic responses to marketing, transport, and feedlot adaptati...

Twelve 364 Ib beef calves were weaned, limit-fed and fasted for three days during the 20-day period after weaning, and then inoculated intranasally with live attentuated infectious bovine rhinotracheitis on day 20. Six of these calves were injected intramuscularly with water soluble vitamins every 2 days from day 9 to day 34. Plasma ascorbic acid and pantothenic acid were depressed by weaning a...

Calfhood diseases have a major impact on the economic viability of cattle operations. The second of this three part review series considers the management of diarrhoeic diseases in pre-weaned calves. In neonatal calf diarrhoea, oral rehydration therapy is the single most important therapeutic measure to be carried out by the farmer and is usually successful if instigated immediately after diarr...

The effects of feeding and intravenous injections of glucose and VFA on blood ghrelin concentrations were investigated in calves before and after weaning. Eight Holstein bull calves were fed whole milk, allowed free access to solid feeds, and weaned at 7 wk. Measurements were carried out at 2, 4, 6, 9, 11, and 13 wk, at which time jugular blood samples were taken from 4 calves through a cathete...