André Mendes Jorge

Tamanho relativo dos órgãos internos de zebuínos sob alimentação restrita e Ad libitum

The effects of genetic group and nutritional level on relative size of internal organs were studied. Sixty-three bulls, 16 Gyr, 16 Guzera, 15 Nellore and 16 Mocho de Tabapua, averaging twenty four months of age, and initial live weight of 376.4, 357.6, 362.0, and 368.6 kg, respectively were used. The animals from each breed were randomly assigned to five groups. One group was immediately slaughtered (AB), three groups were full fed, in individual free stall, a diet containing 50% of concentrate on dry matter basis (group1, 2 and 3), and one group was fed with a restricted amount of the same diet to supply the levels of protein and energy 15% above maintenance (AR). The animals of groups 1, 2 and 3 were slaughtered when they reached the individual live weights of 405, 450 and 500 kg, respectively. At slaughter, the empty body weight (EBW) was determined and the weight of internal organs and viscera were recorded. There were no differences among breed regarding to weight of liver, spleen, small and large intestines, reticulo-rumen, omasum, stomach and gastrointestinal tract (GIT), per 100 kg of EBW. The feed restriction did not affect the weights of heart and lungs, but reduced the weight of liver and GIT components

Exigências de energia para mantença de bovinos zebuínos não-castrados em confinamento

The net requirements of energy for the maintenance of bulls from four Zebu breeds (Gyr, Guzera, Mocho-Tabapua and Nellore) were estimated with 63 bulls averaging 24 months of age and 366 kg initial LW and (15 Nellore and 16 from the Gyr, Guzera and Macho-Tapabua). Fifteen animals, four Gyr, Guzera and Mocho-Tabapua breed and three Nellore breed, were slaughtered at the beginning of the trial and the remaining were allotted to four groups of 12 animals, being three animals from each breed. One group was restricted fed, supplying levels of protein and energy 15,0% over maintenance requirements, according to NRC (1984). The animals of the last three groups were full fed to reach the target live weight slaughter of 405, 450 and 500 kg, respectively. A diet containing 50,0% concentrate as dry matter base and was fed individua lly to all animals. The net energy requirement for maintenance was determined as an estimation of heat production at zero metabolizable energy intake, by extrapolation of the regression equation of log of the heat production on the metabolizable energy intake. The estimated pooled net energy requirements for maintenance for the animals from the four breeds were 60.4 kcal/kgLW.75•day, 21.85%, lower than the value proposed by NRC (1996).

Desempenho produtivo de animais de quatro raças zebuínas, abatidos em três estádios de maturidade: 2. características da carcaça

With the aim to study carcass traits, nine Gyr, nine Guzera, nine Nellore and nine Mocho Tabapua bulls, averaging, respectively, 357.6, 362.0, 368.6, and 376.4 kg of initial live weight and 24 months of age were used in this study. The animals from each breed were randomly assigned to individual pens and were full fed a diet containing 50% concentrate, dry matter basis, until the slaughter weights (405, 450 and 500 kg LW). At slaughter the empty body weight was determined. There were no differences among breeds or slaughter weights on the traits studied, except for whole alcatra cut yield. For this trait there was a interaction effect between breed and category. The yield decreased in Gyr breed, as slaughter weight increased, but did not change in the other breeds. There were no differences among breeds regarding to any one of the physical composition. Slaughter weight did not influence carcass physical composition and loin eye area, however affected the carcass length and back fat thickness.

Desenvolvimento relativo das partes do corpo de zebuínos de quatro raças

Sixty-three intact males, 16 Gyr, 16 Guzerat, 15 Nellore and 16 Mocho Tabapua, averaging, respectively, 376.4, 357.6, 362.0 and 368.6kg initial live weight and twenty-four months of age, were used. The animals from each breed were divided into five groups (categories). One group was ramdomly assigned to immediate slaughter (AB), three groups were full-fed a ration containing 50% concentrate, dry matter basis until reaching the slaughter weights of 405, 450 and 500kg, respectively (group I, II and III). The fifth group was fed a restricted amount of the same ration to supply levels of protein and energy 15% above maintenance (AR). Each AR animal was slaughtered when an animal correspondent to group II reached the slaughter weight. At slaughter, the empty body weight was determined and the weight of internal organs were recorded. Regression equations of log content of internal organs, carcass and their tissues, as a function of log empty-body-weight (EBW), were fitted. The internal organs developed slower in relation to EBW.

Effect of essential oils on meat and fat qualities of crossbred young bulls finished in feedlots.

Twenty-seven animals (½ Angus - ½ Nellore) were fed for four months with one of the following diets: without addition of essential oils (E0.0), with 3.5 (E3.5) or 7 (E7.0) g/animal/day of an essential oil blend (oregano, garlic, lemon, rosemary, thyme, eucalyptus and sweet orange). Chemical composition, fatty acid profile and meat color were evaluated in Longissimus muscle. In addition, the effects of aging (one, seven and 14days) on the meat water holding capacity, texture and lipid oxidation were evaluated. Essential oils had no effect on chemical and fatty acid composition, meat color, water holding capacity or texture, but an inclusion of 3.5g/day decreased lipid oxidation. The addition of 7.0g/animal/day had a pro-oxidant effect on meat during aging and resulted in higher values for lipid oxidation at 14days of aging. Aging significantly affected thawing losses and texture. A dose of 3.5g/animal/day could be recommended in feedlot animals, but greater doses could have a pro-oxidant effect.

Efeito da utilização da somatotropina bovina recombinante (bST) sobre a produção de leite em búfalas

The objective of this work was to study the effect of recombinant bovine somatotropin (bST) utilization on milk production from Murrah buffaloes. Twenty eight multiparous Murrah buffaloes were used and divided into two homogeneous groups of 14 animals, receiving the following treatments: Group 1 - Control (salt solution) and Group 2 - 500 mg of bST/head every 14 days during 7 months. Buffaloes treated with bST presented increase of 48.52%, 32.80% and 32.80% on total milk yield, adjusted to 4% of fat and average daily milk yield, respectively. Somatotropin increased total fat milk yield without alter fat percentage of milk. Administration of bST did not affect protein percentage of milk while total protein milk yield increased. As for the lactating period, the treatment with bST differed of the control, what might have denoted in larger persistence of the lactation from buffaloes treated with bST.

Utilização de método indireto para predição da composição química corporal de zebuínos

The objective of this study was to develop equations to predict chemical body composition from zebu cattle, based on chemical composition from carcass representative section. Sixty-three young bulls from Gyr, Guzera, Nellore and Mocho de Tabapuã breeds were used. Body content of protein, fat and minerals were determined on samples from the carcass section that included the 9th, 10th and 11th rib joint (HH joint), and from the remaining body tissues. Protein, fat, energy and ash contents from the HH joint, except for magnesium, were closely related to protein, fat, energy and ash contents in the body. Prediction equations based on chemical composition from HH joint showed to be reliable for comparative studies of body composition of zebu cattle.The objective of this study was to develop equations to predict chemical body composition from zebu cattle, based on chemical composition from carcass representative section. Sixty-three young bulls from Gyr, Guzera, Nellore and Mocho de Tabapua breeds were used. Body content of protein, fat and minerals were determined on samples from the carcass section that included the 9th, 10th and 11th rib joint (HH joint), and from the remaining body tissues. Protein, fat, energy and ash contents from the HH joint, except for magnesium, were closely related to protein, fat, energy and ash contents in the body. Prediction equations based on chemical composition from HH joint showed to be reliable for comparative studies of body composition of zebu cattle.

Desenvolvimento ponderal de bubalinos da raça Murrah criados em pastagem de Brachiaria brizantha no Centro-Oeste do Estado de São Paulo, Brasil

The weight performance data of Murrah buffaloes from de Dairy Buffalo Production System at Sao Paulo State University, School of Veterinary Medicine and Animal Science, Botucatu-Brazil were analyzed. The weights were corrected at various age-standard and the model included the sex effects (S), month (M) and calfx92s year (A) of birth, age of buffalo cow at calving (C) and S x M, S x A, S x C and M x A interactions. The adjusted means and respective estimated standard-errors for the studied characteristics were: born weight (PN): 37.71 ± 8.25kg; weight at 120 days (P120): 102.08 ± 16.27kg; weight at 240 days (P240): 169.84 ± 22.83kg; weight at 365 days (P365): 250.59 ± 25.12kg; weight at 550 days (P550): 326.13 ± 39.27kg and weight at 730 days (P730): 389.80 ± 31.26kg. There was sex effect (S) only for PN and P365, and males tended to be born heavier than females. The calfx92s of birth (A) influenced on PN, P120, P240 and P730. Calves from buffalo cow of (C) 1 (3 years old or less) and of the class 6 (10 to 12 years) showed weights lighter and heavier, respectively. The fact that the class of the buffalo cow´s age does not exercise effect on P365, P550 and P730, suggests that, in commercial herds the substitution of non-pregnant buffaloes cow by pregnant heifers can be made, in spite of this practice to reduce the average of age of the breeding herd. Murrah buffaloes from dairy herd can be used for the meat production.

Características Quantitativas da Carcaça de Bubalinos de Três Grupos Genéticos Terminados em Confinamento e Abatidos em Diferentes Estádios de Maturidade

This work was conducted to study the quantitative carcass traits of 36 buffaloes (12 Murrah - MUR, 12 Jafarabadi - JAF and 12 Mediterranean - MED) averaging 18 months old and initial body weight (BW) of 330 kg finished in feedlot. Twelve animals of each genetic group were randomly assigned to three sub-groups (four animals) and distributed to the following treatments: Maturity 1 - slaughter weight at 400 kg of BW, Maturity 2 - slaughter weight at 450 kg of BW, or Maturity 3 - slaughter weight at 500 kg of BW. Animals had free access to a diet containing 50% of forage (DM basis). After each slaughter empty body weight (EBW) was determined through the sum of body parts. No differences among genetic groups and maturity were observed for yields of hind and forequarters, whole shoulder and whole rump. However, animals slaughtered at 400 kg of BW had lower yield of beef plate than those slaughtered at 500 kg of BW while animals on treatment 2 were intermediate. Opposed behavior was observed regarding whole shoulder yield. Production of meat from Murrah, Jafarabadi and Mediterranean did not differ for yields of carcass yield and prime cuts.

Crescimento relativo e composição do ganho de tecidos da carcaça de zebuínos de quatro raças

Sixty four uncastrated males from zebu breeds Gyr, Guzerat, Mocho de Tabapua and Nellore were used. The animals from each breed were divided into five groups (categories). One group was ramdomly assigned to immediate slaughter, three groups were full-fed a ration containing 50% concentrate, dry matter basis until reaching the slaughter weights of 405, 450 and 500 kg, respectively (group I, II and III). The fifth group was fed a restricted amount of the same ration to supply levels of protein and energy 15 % above maintenance. Regression equations of log content of carcass and their tissues (muscle, adipose tissue and bone), as a function of log empty-body-weight, were fitted. Adipose, bone and muscular tissue presented higher growth in late, early and intermediary age, respectively. Carcass presented positive allometry reflecting greater proporcional development in relation to empty-body-weight.