Patrícia Rossi

Valor nutritivo do feno de braquiária amonizado com uréia ou inoculado com Pleurotus ostreatus

The effect of a chemical treatment (ammoniation with urea) or a biological treatment (innoculation with the fungus Pleurotus ostreatus) on the nutritive value of Brachiaria decumbens hay was evaluated by means of chemical analyses and a digestibility trial with sheep. Both treatments lasted 42 days, and thereafter the hay was dried and ground for animal feeding. The experimental diets were the following: untreated Brachiaria hay (FNT); untreated hay plus urea added in the trough (FNT+U); fungus-treated hay plus urea (FTB+U); and ammoniated hay plus untreated hay (FTQ+FNT). The FNT+U, FTB+U and FTQ+FNT diets were isonitrogenous. Both the chemical and biological treatments caused changes in hay chemical composition. Ammoniation raised crude protein (CP) and acid detergent fiber (ADF) contents and reduced both hemicellulose(HEM) content and the proportion of hemicelullose in cell walls (HEM-NDF). The biological treatment tended to raise CP; it increased ADF, lignin (LIG), cellulose proportion in cell walls (CEL-FDN) and lignin proportion in cell walls (LIG-FDN); it reduced neutral detergent fiber (NDF), HEM and HEM-NDF. However, it reduced dry matter (DM), NDF, cellulose (CEL) and FDA digestibility; however, it increased intake, probably due to smaller NDF content and smaller particle size, causing a higher rate of passage. Both the biological and chemical treatments are important alternatives in increasing the nutritive value of lignocellulosic materials. Nevertheless, the results obtained in this experiment were not satisfactory.

Ingestive behavior of Nellore cows and their straightbred or crossbred calves.

This trial aimed to investigate the influence of calf genetic group on the ingestive behavior of Nellore dams and their offspring on pasture. Twenty one primiparous and multiparous Nellore cows were assigned to the experiment; 13 cows nursed straightbred Nellore calves; and eight cows nursed halfbred Simmental × Nellore calves. The observations started in the morning, as soon as identification of the animals in daylight was possible, and they lasted until after sunset, when identification became impossible. The observations were made at 3, 6, 12, 24 and 30 weeks after calving. The following events were continuosly observed: grazing, rumination, idleness, water and mineral intake, and suckling frequency and length.. The dams of straightbreds showed a shorter rumination time and longer idleness. Nellore calves showed shorter grazing time and higher suckling frequency. The ingestive behavior of Nellore cows on pasture is affected by the genetic group of their offspring, possibly because of the suckling frequency of the calves.

Voluntary intake of dry matter and performance of Nellore cows and their Nellore and crossbred Simental × Nellore calves

This study aimed to investigate the influence of calf genetic group on the performance of Nellore lactating cows. The variables studied included milk ingestion, pasture intake, calf weight gain and cow body weight. A total of 13 Nellore calves and 8 crossbred Simental × Nellore calves were used, all born from Nellore mothers. During the experimental period of 210 days, calves were weighted at birth and at 30-day intervals, whereas cows were weighed every 14 days. Milk intake was estimated using the weigh-suckle-weigh method. Pasture intake was determined 6, 12, and 24 weeks after birth by using chromic oxide as an external marker and indigestible acid detergent fiber as an internal marker. Average weight of crossbred calves was 10.1 kg and their milk intake was 0.42 kg higher than in purebred calves. There was no difference, however, in pasture intake between genetic groups. In Nellore cows, body weight and pasture consumption (9.2 kg of DM/cow/day) were not influenced by calf heterosis.

EFEITO DO ADSORVENTE A BASE DE GLUCOMAMANO ESTERIFICADO NO DESEMPENHO E CARACTERIZAÇÃO VISCERAL DE FRANGOS DE CORTE

O objetivo desse trabalho foi avaliar o efeito do uso de um adsorvente de micotoxinas constituido a base de glucomanano esterificado (GME) adicionados a dieta a base de milho e soja contaminados com aflatoxina (AF) sobre o desempenho, caracteristicas de carcaca e lesao macroscopicas de orgaos viscerais de frangos de corte. O delineamento experimental foi em blocos ao acaso, com 2 niveis de AF e 2 niveis de GME, ou seja, 4 tratamentos de 7 repeticoes com 28 aves cada, totalizando 784 aves. Aves alimentadas com dietas contendo aflatoxina apresentaram menor no ganho de peso, consumo de racao, aumento do peso relativo do baco, coracao, moela e proventriculo e maior incidencia de lesoes no baco quando comparadas com aves recebendo dietas sem contaminacao por aflatoxina . Nao houve efeito significativo do adsorvente a base de glucomanano esterificado sobre as variaveis de desempenho, caracteristicas de carcaca, peso relativo dos orgaos e percentagem de lesao macroscopica nos orgaos, com excecao da mortalidade (P dietas contaminado com aflatoxina afeta negativamente o desempenho produtivo, caracteristicas de carcaca e orgaos de frangos de corte e que a inclusao do adsorvente GME em dietas de frangos de corte contendo milho contaminado com AF nao alterou o desempenho e caracteristicas de carcaca de frangos de corte. Palavras-chave: aflatoxina , adsorvente , consumo de racao, ganho de peso, lesao macroscopica ABSTRACT The objective of this study was evaluate the effect of sterified glucomannan adsorbent of mycotoxin add to corn-soy diets contaminated with aflatoxin (AF) on growth performance, carcass characteristics, and macroscopic lesion on visceral organs of broiler chickens. A total of 784 birds were subjected to a completely randomized block design, including 4 treatments and 7 replicates with 28 birds each per treatment. The birds receiving diets contaminated with AF showed lower body weight gain, feed consumption, higher relative spleen, heart, gizzard and proventriculus weight and higher spleen lesions compared with birds receiving diets without AF. Performance, carcass characteristics, relative organ weight and macroscopic organ lesion were not affected by dietary treatments exception to mortality (P supplementation with sterified glucomannan in diets with AF no affect the performance and carcass characteristics of broilers chickens. Keywords: aflatoxin , adsorbent, feed intake, weight gain, macroscopic lesion.