The aim of this study was to evaluate the productive performance of laying quails (Coturnix coturnix japonica). The study was carried out at the poultry farm of the La Molina National Agrarian University in Lima, Peru. In total, 1296 quail distributed in 96 females and 48 males of three ages (45, 52 and 59 days) with 130, 140 and 150 g of body weight, respectively, at the beginning of the laying were used. A random block design with a 32 factorial arrangement was used, taking as factors age and weight at the beginning of laying and as a block the weeks of laying (8, 11 and 17). The highest egg mass (10.72 ± 0.41 g/day/bird) was obtained when the quails started laying with 150 g of live weight.

The aim of this study was to evaluate the influence of the age of bulls at grazing on their diurnal behaviour in Setaria sphacelata meadows. The forage variables were the availability and nutritive value of the diet, and the animal variables were body weight, size and frequency of bites, and diurnal behaviour. Four Brown Swiss x zebu crossed bulls with an initial live weight of 285.8 ± 18.1 kg that grazed in an area of 29 ha (11 paddocks) were selected from a group of 36 bulls. The evaluations were done when the animals reached the ages of 12 (T1), 15 (T2) and 18 (T3) months. A randomized complete block design was used. Forage availability showed differences (p<0.05) between treatments; however, the forage allocation and the nutritional quality of the diet did not compromise their performance. Bite weight was higher in T3 (0.87 ± 0.22 g per bite; p<0.05), but without differences ...

The aim of this study was to relate morphometric measurements of the Coturnix coturnix japonica quail egg with the weight at birth in a commercial line of laying. In total, 274 birds were evaluated at one-day old, whose fertile eggs were classified into three categories according to weight: (1) 10.00-10.99, (2) 11.00-11.99, (3) 12.00-12.99 g for the variable birth weight, while the variables: transverse diameter and longitudinal diameter of the egg, and shape index were evaluated according to quartiles. In addition, the sex of the bird was evaluated. A completely randomized block model and correlations between the quantitative variables were used. A mean correlation of 0.65 was obtained between egg weight and longitudinal diameter, and low correlations between the variables longitudinal and transverse diameter (0.15). The birth weight was 7.36 ± 0.038, 7.92 ± 0.036 and 8.47 ± 0.058 g ...