Ninety Angus × Hereford calves were ranked by sex, BW, and age and assigned to 1 of 3 vaccination schemes against the bovine respiratory disease complex: 1) vaccination at weaning (d 0) and a booster at feedlot entry (d 30; CON; = 30), 2) vaccination 15 d before weaning (d -15) and a booster 15 d before feedlot entry (d 15; EARLY; = 30), and 3) vaccination 15 d after weaning (d 15) and a booste...

The objectives of this study were to compare innate immune responses of calves weaned early (EW; n=23; weaned at 23.7 ± 2.3 d of age) with those of conventionally weaned calves (CW; n=22; weaned at 44.7 ± 2.3 d of age). All calves were fed 3.8L of colostrum within 12h of birth and were subsequently fed milk replacer twice daily. The weaning process began by withdrawal of the afternoon milk-repl...

We determined regional myocardial blood flow (15-micrometer tracer microspheres) and hemodynamics in nine normal calves, seven calves with right ventricular (RV) hypertrophy induced by pulmonary artery banding (PAB) at sea level, and five calves exposed to simulated high altitude (HA) of 3,500 m (PB = 500 mm Hg) for 8--10 weeks. Progression of RV hypertrophy was very rapid in HA calves. RV weig...

Data were 876 birth records and 727 weaning records of straightbred and F3 crossbred calves produced in the third generation of a five-breed diallel. Among straightbreds at birth, Holstein calves were heaviest and widest at the shoulders and hips. Jersey calves were lightest and narrowest at the hips, and Brahman calves were narrowest at the shoulders. Holstein crosses tended to be larger at bi...

Two trials, involving 469 steer and heifer calves, were conducted to evaluate the practices of implanting or reimplanting suckling fall-born calves with progesterone-estradiol benzoate (PE) implants (100 mg of progesterone, 10 mg of estradiol benzoate). Calves having an average initial weight of 67 kg were randomly allocated within sex and location to remain either nonimplanted or to receive a ...

The objectives of this study were to determine incidence of stillbirths and heifer-calf morbidity and mortality, and their association with dystocia on 3 Colorado dairies. A total of 7,380 calvings produced 7,788 calves on 3 Colorado dairy operations between October 1, 2001, and November 5, 2002. Dystocia score and calf status (alive vs. dead) were recorded at calving. Calves that were born ali...

A 3-yr study used 16 cows and their spring-born calves (yr 1) and 48 first-calf heifers (yr 2, n = 24; yr 3, n = 24) and their spring-born calves in a completely randomized design. All cows and heifers were Angus x Beefmaster, and calves were sired by Angus bulls. Cow-calf pairs were assigned randomly to one of two management systems: 1) an early-weaning system, in which steer and heifer calves...

The objective of this research was to determine the influence of dietary Se on various indicators of Se status and relative liver glutathione peroxidase 1 (GPx-1) messenger RNA (mRNA) levels in growing Holstein bull calves. Calves (n = 14, 7/diet) were started 28 d after birth on a Se-adequate (SeA) or Se-deficient diet (SeD) and maintained on the diet until 180 d of age. Blood samples were tak...

OBJECTIVE To determine the effect of transportation stress on serum concentrations of oxidative stress biomarkers of calves. ANIMALS 105 crossbred beef steer calves (mean [+/-SD] body weight, 207 +/- 21.2 kg). PROCEDURE Calves were assembled at 1 location in Tennessee, and pretransit (day -3) blood samples were collected. Calves were allotted randomly by body weight into 2 groups. Calves we...

This study investigated the influence of stockperson's behaviour and housing conditions on calves' behavioural reactions to people, and behavioural and physiological reactions to handling and short transport. Sixty-four Finnish Ayrshire male calves were used; half of them were housed in individual pens, the other half were housed in group pens of two calves. In both housing conditions half of t...