Economical and biological efficiencies of beef production to weaning and to slaughter were estimated in three groups, different in milk available (low, medium, and high) to the calves but with the same potential for growth. Data from different breed groups of cows (low [L] = Hereford x Angus, medium [M] = Red Poll x Angus, and high [H] = Milking Shorthorn x Angus) were used. Economical efficien...

The objectives of this study were 1) to propose a profit function for Italian Chianina beef cattle; 2) to derive economic values for some biological variables in beef cows, specifically, production expressed as the number of calves born alive per year (NACY), age at the insemination that resulted in the birth of the first calf (FI), and length of productive life (LPL); and 3) to investigate the...

Balancing growth and reproductive performance in beef cattle managed in desert environments is challenging. Our objectives were to 1) evaluate trends in growth and reproductive traits, and 2) assess associative relationships between growth characteristics and reproductive performance in a Brangus herd managed in a Chihuahuan Desert production system from 1972 to 2006. Data were from bull (n = 5...

A 3-yr study evaluated late winter (Feb), early spring (Apr), and late spring (Jun) calving systems in conjunction with varied weaning strategies on beef cow and calf performance from Northern Great Plains rangelands. Crossbred cows were randomly assigned to one of three calving systems (on average n= 168.calving system(-1).yr(-1)) and one of two weaning times (Wean 1, 2) within each calving sy...

North Atlantic right whales (NARW) are critically endangered and have been declining in abundance since 2011. In the past decade, human-caused mortalities from vessel strikes entanglements increasing, while birth rates population at a 40 yr low. addition to abundance, recent studies shown that NARW length-at-age is decreasing due energetic impacts of sub-lethal entanglements, body condition poo...

Production data from 11 southeastern Montana ranches were used to parameterize a bio-economic computer model of cow/calf range production. Effects of changes in breeding date, weaning date, and range removal date on system performance for a ranch with a fixed forage resource base (3,060 animal unit months of range forage and 744 t of hay) were simulated. Input costs were locally established in ...

Factors affecting calving interval (CI) in double-muscled Belgian Blue (DMBB) beef cows were investigated with regard to the BW yield (BWY) of the cow-calf pair, using 834 CI records from 386 females with parities 1 to 6. The effect of parity and CI on BWY was also studied. Cow-calf pair BWY was defined as calf birth weight plus dam BWY per CI. CI (mean±s.e.: 404±1.9 days) was affected by parit...

AIM This study was undertaken to determine the household, calf management, and calf factors associated with the occurrence of Eimeria, Cryptosporidia, and diarrhea in pre-weaned calves reared in smallholder dairy farms in Mukurwe-ini Sub-County of Nyeri County, Kenya. In addition, the study also evaluated factors associated with average daily weight gain in the same pre-weaned calves. MATERIA...