Borra de manipueira em substituição ao milho na dieta de cabritos

Abstract

We evaluated the effect of replacing corn by grounds of cassava wastewater (0, 33, 66 and 100%) in the diet of crossbred dairy young goats on intake, nutrient digestibility, feeding behavior, performance, blood parameters, carcass characteristics and meat quality. 36 male goats were used, not castrated, aged 4 and 5 months, with initial body weight 17.61 kg ± 1.98, distributed in a completely randomized design. Food consumption was calculated by the difference between the amount of food provided and the remains of the animals and the relationship between feed intake and weight gain were obtained feed conversion values. For calculation of the digestibility of dry matter and nutrients used to Indigestible Neutral Detergent Fiber as an internal marker to estimate the production of faecal dry matter. The feeding behavior was carried out by recording the daily time spent on food consumption, rumination and idleness. Blood samples were collected by jugular venipuncture. In addition to the erythrocyte and bleeding times, the biochemical parameters determined in the blood were: creatinine, urea, uric acid, glucose, albumin, globulin, total protein, cholesterol, triglycerides, alkaline phosphatase, Gamma glutamyl transferase, Aspartate aminotransferase, Alanine aminotransferase, Triiodotiroxina hormone, Thyroxine free hormone and Thyroid stimulating hormone. After slaughter, carcasses were weighed to obtain the hot carcass weight and then cooled in cold storage at 4°C for a period of 24 hours, and then determined the cold carcass weight loss and cooling. Next was conducted evaluation of conformation and measurements of carcass lengths. Preceded the carcasses measures were divided into two half-carcasses, which were weighed and then analyzed the income of commercial cuts (leg, shoulder, loin, ribs, handsaw and neck). Between the 12th and 13th rib was made a horizontal cut aimed at exposing the Longissimus dorsi (loin eye area), to trace its outline on paper transparency, and the area of the figure subsequently determined by a digital planimeter. The left hind legs were dissected to estimate the yield of tissue in muscle: fat and muscle: bone, and muscularity ham. Samples of semimembranous muscle were lyophilized to perform the determination proximate which were determined humidity percentages, protein, ash ethereal eestrato. For qualitative analysis of meat were used left loin (longissimus lumborum) determining for each animal whether the cooking losses, shear strength, color, water-holding capacity and pH. Data were subjected to analysis of variance and regression and all means comparisons were by Dunnett test. Regression analysis showed no effect of replacing corn by grounds of cassava wastewater on dry matter intake (kg / day) and total digestible nutrients. Providing negative linear effect on the consumption of fiber in neutral and positive linear detergent on total carbohydrate consumption and non-fibrous and HCN as they increased the proportion of grounds of cassava wastewater in the diet. The digestibility of organic matter and total carbohydrates and fibrous carbohydrates were positively linear effect. The results obtained with the intake and digestibility were not decisive to affect performance and feeding behavior of the animals. Exposure to low concentrations of HCN during 65 days did not affect convincingly in the red series of animals. Apparently, there was no loss in endocrine pancreatic function, liver, kidney and thyroid of animals. There was no influence of the substitution of corn by cassava dregs on carcass characteristics, weight and yield of commercial cuts, morphometric measurements, tissue composition, or on the characteristics of physical and chemical quality of the meat. Given the results can be concluded that the grounds of cassava wastewater can replace corn in up to 100% in the diet of dairy goats in the feedlot.