Desempenho reprodutivo de cinco linhagens de aves da raça Leghorn branca e dois de seus cruzamentos.

An experiment involving five pure lines of white Leghorn hens was conducted to evaluate their productive performance, compared with two crosses derived from two of them and a commercial strain. The research was done at the poultry section of "Departamento de Zootecnia at Universidade Federal de Santa Maria, RS, Brazil, from August 1983 to September 1984. When the pullets reached 20 weeks of age they were set in laying cages (eight pullets per cage), in an arrangement of eight treatments, with six replicates each. They were fed a diet with 16,5% crude protein and 2,800 Kcal EM/kg. The analysed data were: daily feed intake, body weight, egg production, egg weight, egg mace, feed conversion, feed efficiency, egg specific gravity and Haugh units. The results showed similar productive performance of the lines C, E, F, and G compared to the commercial strain, in spite of the low production of this group of hens. The body weight of two cross lines CE and EC were significantly higher than all the other lines, showing effects of heterosis for this variable, which probably caused their low productive performance. O experimento foi desenvolvido como objetivo de avaliar o potencial produtivo de cinco linhas puras de poedeiras Leghorn branca (C, E, F, G e H) e de dois cruzamentos provenientes de duas delas (CE e EC), comparados com uma linha comercial. A fase experimental foi desenvolvida no setor de avicultura do Departamento de Zootecnia da Universidade Federal de Santa Maria, RS, de agosto de 1983 a setembro de 1984. As aves foram alojadas, às vinte semanas de idade, em gaiolas de postura, com oito aves por gaiola, compondo oito tratamentos de seis repetições cada um. As aves receberam ração com 16,5% de proteína bruta, 2.800 Kcal de EM/kg. Os parâmetros analisados foram: consumo alimentar diário, peso corporal, produção de ovos, peso do ovo, massa do ovo, conversão alimentar, eficiência alimentar, gravidade específica do ovo e unidades "Haugh". Os resultados de produção mostram que as linhas C, E, F e G foram semelhantes à testemunha, apesar dos baixos índices produtivos destas últimas. Os cruzamentos CE e EC foram mais pesados, diferindo significativamente das demais linhas, apresentando efeito de heterose para esta característica, e provavelmente os baixos desempenhos devem-se ao maior peso destas aves.

Carrot tops as a partial substitute for alfalfa hay on diets for growing rabbits

The aim of this study was to evaluate the feasibility of partially replacing alfalfa hay with carrot tops (Daucus carota) in diets for broiler rabbits. The assay was composed of 30 New Zealand rabbits, weaned at 35 days of age, divided into 3 groups and submitted to one of three dietary treatments: T0CT – Diet without the inclusion of carrot tops; T25CT - diet with replacement of alfalfa hay by 25% carrot tops; and T50CT - diet with replacement of alfalfa hay by 50% carrot tops. Water and feed were offered ad libitum. The biological assay lasted for 49 days and took place during the months of December and January (summer season). The following parameters were evaluated: weight gain, feed conversion, feed intake and economic viability of the diet. Means were statistically analyzed by analysis of variance (ANOVA) followed by Tukey test (0.05). The average daily weight gain of the rabbits was 23.93 g for T0CT, 22.65 g for T25CT and 22.16 for T50CT (p>0.05). Feed intake was 86.71 g in T0CT, 88.43 g in T25CT and 89.57 g in T50CT (p>0.05). The feed conversion ratio was 3.62 for T0CT, 3.09 for T25CT and 4.04 for T50CT (p>0.05). The cost per kg of diet linearly reduced with the inclusion carrot tops, and the T0CT diet was the most expensive (R$0.74/kg or US$0.22) and T50CT (R$0.60/kg or US$0.18) the most economically viable. It can be concluded that carrot tops can replace up to 50% of the alfalfa hay in diets for growing broiler rabbits, optimizing the cost of diet without negatively affecting animal performance.O objetivo deste estudo foi avaliar a viabilidade da substituição do feno de alfafa por topos d

Inclusão de glicerina bruta em dietas para coelhos em crescimento

The present study aimed to evaluate the performance of rabbits during growth fed diets containing different levels of glycerin to replace the commonly used energy foods. For the experiment, we used 30 rabbits of New Zealand White weaned at 34d. After three days of adapting the animals were distributed in three treatments: G0= standard diet without adding glycerin, G5= diet containing 5 % glycerin and G7,5= diet containing 7.5 % glycerin. The biological assay was conducted in the Brazilian winter in 2013. The rabbits were slaughtered at 85d totaling 48d of bioassay. The parameters evaluated were final live weight, daily feed intake, feed conversion, average daily gain, carcass yield, liver weight, kidney weight, and heart weight. The three treatments showed no differences in the use of glycerin on performance variables. It is therefore concluded that the inclusion of glycerin in diets for rabbits in the growth phase is workable, because does not change the performance thereof.O presente estudo teve por objetivo avaliar o efeito de diferentes níveis de glicerina em substituição a alimentos energéticos comumente utilizados em dietas sobre o desempenho de coelhos na fase de crescimento. Foram utilizados 30 coelhos da raça Nova Zelândia Branca, desmamados aos 34 dias de idade. Após três dias de adaptação os animais foram distribuídos em três tratamentos: G0= dieta padrão sem inclusão de glicerina bruta, G5= dieta contendo 5 % de glicerina bruta e G7,5= dieta contendo 7,5 % de glicerina bruta. O ensaio biológico foi conduzido no inverno brasileiro no ano de 2013. Os coelhos foram abatidos aos 85 dias totalizando 48 dias de ensaio biológico. Os parâmetros avaliados foram: peso vivo final, consumo diário de ração, conversão alimentar, ganho médio diário, rendimento de carcaça, peso do fígado, peso dos rins, e peso do coração. Os três tratamentos não apontaram diferenças na utilização de glicerina nas variáveis de desempenho. Conclui-se, portanto que a inclusão de 7,5 % de glicerina em dietas para coelhos na fase de crescimento é viável, pois não altera o desempenho dos mesmos