FERREIRA, M. A. A.; http://lattes.cnpq.br/9558579428935676; FERREIRA, Maria Andréa Amorim.
Résumé:
This work aimed to estimate the nutritional requirements of protein, energy,
calcium and phosphorus for weight gain of Santa Inês sheep with different
genders. The experiment was carried out at the Research Center for the
semiarid region (NUPEÁRIDO), Federal University of Campina Grande (UFCG),
Patos-PB. Twenty-four 80˃5 day-old sheep were used, including 12 males and
12 females, with an average body weight (BW) of 15 Kg. The effect of 0%, 25%
and 50% of food restriction was analyzed to both genders. The diet consisted of
elephant grass hay and concentrate with a ratio of 50:50
(roughage:concentrate), in a confinement system. The body composition per Kg
of the sheep varied from 285.98 to 320.16 g of dry matter, 41.60 to 46.96 g of
mineral matter, 60.97 to 83.93 g of fat, 160.44 to 175.71 g of protein, 1.49 to
1.80 Kcal of energy, 8.71 to 9.83 g of calcium and 7.01 to 7.81 g of phosphorus
per Kg of BW. The protein concentration in the animal body increased from 152
to 182 g/Kg (P<0.01) when the animals' weight increased from 15 to 30 Kg. The
energy content per Kg of empty body weight gain (EBW) ranged from 2.21 to
3.39 Mcal. Estimates of body composition as a function of EBW for calcium and
phosphorus increased from 97 to 203 g and from 94 to 175 g*Kg-1, respectively,
as body weight increased from 15 to 30 Kg. The net requirements of protein and
energy were similar for both genders to all analyzed variables (Pޓ0.05). The
values observed in this study were lower than those recommended by
international systems. Net protein and energy requirements were similar for
both males and females and increased with increasing body weight. The
estimate of protein requirements was similar to that presented in the National
Research Council (NRC), while energy was 27% lower.