title: Productivity and profitability of twin births in beef cattle.
abstract: Data from 1,277 single and 85 twin calvings, occurring in both spring and fall from 1980 through 1987, were used to examine the productivity and profitability associated with twin births in beef cattle. Pregnancies in pure and crossbred cattle resulted from both AI and embryo transfer. Cows and calves were confinement-housed. Cows were individually fed to specification. Calves were given ad libitum access to creep feed and those born in 1986 and 1987 were fed to slaughter. The influence of birth number of gestation length, total calf birth and weaning weights, lactation yield, and cow fed intake during both the dry and lactating periods were examined. Twin-bearing cows had their gestation length shortened by 6.4 d (2%); yielded 25.5 (59) and 186.0 kg (73%) more weight of calf at birth and weaning, respectively; had lactation yield and lactation feed intake increased by 25 and 20%, respectively; and had precalving (dry) period feed intake no different from their single-bearing counterparts (P = .12). Postweaning growth was not different for single and twin calves (P = .50); twin gain, relative to initial size, was higher. Feedlot feed intake of twins was 85% of that for singletons (P = .20). Twins were 90% of singleton live weight at slaughter and yielded 93% of singleton hot carcass weight (P = .12). Twins were slightly older and significantly leaner at slaughter. Returns less feed costs showed twin births to be associated with increased profit for cow-calf programs. Returns less feed and overhead costs were higher for twin calves than for singles in the feedlot.
authors.affiliation: University of Guelph, Ontario.
authors.forename: E P
authors.initials: EP
authors.lastname: de Rose
authors.forename: J W
authors.initials: JW
authors.lastname: Wilton
mesh_terms: D000273:Adipose Tissue / Q000254:growth & development; D000383:Agriculture / Q000191:economics*; D000821:Animal Feed / Q000191:economics; D000818:Animals; D001823:Body Composition; D002417:Cattle / Q000254:growth & development / Q000502:physiology*; D003365:Costs and Cost Analysis; D004435:Eating; D004624:Embryo Transfer / Q000662:veterinary; D005260:Female; D007315:Insemination, Artificial / Q000662:veterinary; D007774:Lactation; D016018:Least-Squares Analysis; D008297:Male; D008460:Meat / Q000592:standards; D011247:Pregnancy; D014427:Twins; D014886:Weaning; D015430:Weight Gain