Naslov
Components of growth in mice hemizygous for a MT/bGH transgene

Autori
Kapš, Miroslav ; Moura, A.S.A.M.T ; Safranski, T.J. ; Lamberson W.R.

Izvornik
Journal of Animal Science (0021-8812) 77 (1999); 1148-1154

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
Mice; Transgenics; Composition; Somatotropin.
(Mice; Transgenics; Composition; Somatotropin)

Sažetak
The objective of this study was to determine the effects of a metallothionein/bovine GH transgene on duration and rate of growth of lean and fat in mice. Mice were produced by mating hemizygous transgenic males to nontransgenic females, Ten weights and six measurements of total body electrical conductivity to estimate body composition were taken on 147 progeny between birth and 84 d of age. Growth traits for fat-free mass (FFM) and body fat mass (FM) were obtained by fitting FFM and FM to a logistic curve y = A/(1 + exp(k(b - t))), where y is FFM or FM, A is asymptotic mass, k and b are curve parameters, and t is time in days. The function and its first, second, and third derivatives for FFM and FM were used to model growth. A mixed model was used with animal and litter as random effects and transgenotype, sex, and transgenotype x sex as fixed effects in analyses of growth traits. Estimates of transgenotype and transgenotype x sex interaction were tested by using their corresponding standard errors. Males had greater response to the transgene than females in final FFM and growth rate during the entire growth period. Transgenic males and females had greater duration of lean growth than nontransgenics. Transgenic males began to accumulate fat later, but they eventually gained more fat than transgenic females.

Izvorni jezik
Engleski

Znanstvena područja
Poljoprivreda (agronomija)

POVEZANOST RADA