Dari Celestino Alves Filho

Características de carcaça de bovinos de corte inteiros ou castrados de diferentes composições aciais Charolês x Nelore

The carcass characteristics from young bulls or steers from different breed compositions of Charolais x Nellore were the objective of this study. Seventy beef males from three breeding systems: straightbreds (Charolais (Ch) and Nellore (Ne)), G1 crossbreds (1/2 Ch 1/2 Ne and 1/2 Ne 1/2 Ch) and G2 crossbreds (3/4 Ch 1/4 Ne and 3/4 Ne 1/4 Ch) were used. Thirty-five males were castrated (steers) at seven months and 35 were kept entire (young bulls). The animals were confined from 20 month to the slaughter time, at 24 months of age. No interaction was observed between breed composition and sexual condition, for any of the studied variables. The young bulls showed higher slaughter and carcass weight, forequarter and muscle percentage and conformation, while the steers showed higher fat thickness, fat, pistol cut and sidecut percentage. Among breeding systems, crossbreds animals showed higher values for slaughter weight, carcass weight, dressing percentage, carcass length, leg length, cushion thickness and arm perimeter, and the heterosis values were 16.36, 20.10, 3.08, 3.71, 4.09, 6.04 and 4.56% in G1, and, in G2, of 10.03, 11.48, 1.09, 3.02, 2.49, 6.08 and 4.56%, respectively. Comparing the Ch and Ne breeds, the first showed higher slaughter and carcass weight, while the dressing percentage and carcass fat thickness were better in Ne animals. There was no difference among 1/2 Ch 1/2 Ne and 1/2 Ne 1/2 Ch animals for any one of the studied traits.

Características da carcaça de novilhos de gerações avançadas do cruzamento alternado entre as raças Charolês e Nelore, terminados em confinamento

The objective of this work was to evaluate the carcass characteristics of feedlot finished steers, straightbreds (Charolais - C and Nellore - N), and crossbreds from second (G2) (¾C ¼N and ¾N ¼C), third (G3) (5/8C 3/8N and 5/8N 3/8C) and fourth (G4) (11/16C 5/16N and 11/16N 5/16C) generations of rotational crossbreeding. Crossbreds showed higher slaughter, hot and cold carcass weights than the average of the purebreds, being the total heterosis, respectively, 14.95; 18.72 and 18.39% in G2, 19.98; 24.16 and 24.59% in G3 and, 18.38; 22.55 and 22.88% in G4. Total heterosis for the three characteristics followed the fluctuation of individual heterozygosis. Heterosis for hot and cold carcass dressing percentage was significant in all generations, being the retained heterosis, respectively, 3.22 and 3.71%. Carcass chilling loss in G2 did not differ from purebreds, but was significantly lower in G3 (-16.73%) and G4 (-12.84%). For carcass physiological maturity, heterosis was negative and significant in G3 and G4. Subcutaneous fat thickness was higher for the crossbreds of the three generations, however, was only significant in G4. For the characteristics related to carcass muscling, heterosis was significant in the three generation for conformation and Longissimus dorsi area, for cushion thickness and arm perimeter, although positive in the three generations, reached significance only in G3 and G4, being the retained heterosis, respectively, 8.09; 11.33; 7.45 and 5.95%. The characteristics related to corporal development showed significant heterosis in all generations, being the retained heterosis 8.55; 5.73 and 4.99%, respectively, for carcass, leg and arm length. The proportion of commercial cuts of the carcass was not affected by heterozygosis, but for their absolute values, heterosis was significant following the carcass weight behavior.

Animal productivity and economic return in oat plus ryegrass pasture fertilized with sources of nitrogen

The objective of this experiment was to evaluate the animal productivity and economic return of the use of urea or ammonium sulfate for fertilization of oat (Avena strigosa Schreb) plus ryegrass (Lolium multiflorum Lam.) pasture. The pasture was established on 04/21/94 and the grazing period occured from 06/05 to 11/06/94. The continuous grazing method with variable stocking rate was used. The animals used were beef heifers, with 10 months of age. The amount of nitrogen used was 200 kg/ha, subdivided in three applications. The source of nitrogen did not significantly affect the average daily gain, .579 and .615 kg, the stocking rate, 873 and 842 kg of live weight/ha and the live weight gain/ha, 428 and 453 kg/ha, for urea and ammonium sulfate, respectively. Nitrogen fertilization represented 34.10 and 47.56% of the total cost of the pasture, when urea and ammonium sulfate were used, respectively. The gross income was of U

Órgãos internos e trato gastrintestinal de novilhos de gerações avançadas do cruzamento rotativo entre as raças Charolês e Nelore terminados em confinamento

299.50 and 318.00/ha and the net income was of U

Desempenho de Novilhos Red Angus Superprecoces, Confinados e Abatidos com Diferentes Pesos

47.90 and 1.90/ha, for urea and ammonium sulfate, respectively. Since no significant difference occurred in live weight gain/ha, the decision of using urea or ammonium sulfate for fertilization of annual winter pasture should be based on the price per kg of nitrogen.

Características quantitativas da carcaça de novilhos jovens e superjovens de diferentes grupos genéticos

The objective of this trial was to investigate the effect of heterosis and genetic group on the yield and weight of internal organs and gastrointestinal tract (GIT) of feedlot purebred (Charolais C and Nellore N) and crossbred steers from second (G2) (¾C ¼N and ¾N ¼C), third (G3) (5/8C 3/8N and 5/8N 3/8C) and fourth (G4) (11/16C 5/16N and 11/16N 5/16C) generations of rotational crossbreeding slaughtered at 23 month of age. Crossbred steers from G2, G3 and G4 had, respectively, 14.95, 17.25 and 18.46% higher empty body weight (EBW) than that from purebred animals. A positive heterosis for cold carcass yield expressed as a proportion of EBW (CCYEBW) was observed in G2, G3, and G4. Weights of heart, lungs, and kidneys adjusted for EBW were lower on crossbred compared to purebred steers; the heterosis was significant for the weights of heart (-18.29%) and kidneys (-14.29%) in G3 and for that of lungs (-13.45%) in G4. Weights of all organs of the GIT either expressed as 100 kg of EBW or as proportion of slaughter body weight (SBW) were lower on crossbred than on purebred steers with the exception of rumen weight in G2. Retained heterosis was positive and significant for EBW, CCYEBW and liver weight. However, it was negative for amount of blood and weights of heart and small plus large intestines when expressed as 100 kg of EBW and SBW. Within purebred animals, N showed greater CCYEBW (61.64%) than C (57.09). Conversely, weights of rumen, abomasum, small plus large intestine, and GIT were all higher on C than N steers; excepting for small plus large intestine, the same was observed when weights of the remaining GIT components were expressed as proportion of EBW and SB. These differences partially explain the increased carcass yield on N steers.

Produção e composição do leite de vacas de quatro grupos genéticos submetidas a dois manejos alimentares no período de lactação

The feedlot performance of Red Angus steers, with initial age of eight months and 189 kg of initial live weight, fed to reach the slaughter weight (SW) of 340, 370, 400 or 430 kg, was evaluated. The number of days to reach the respective weight was 114, 144, 168 and 209 days, with 12, 13, 14 and 15 months of age. The animals were fed with a 13.13% crude protein diet, and roughage:concentrate ratio of 56:44. The average daily gain was 1.32, 1.27, 1.23 and 1.15 kg, respectively. Dry matter intake (DMI) expressed in kg/day/animal and metabolic weight, did not show significant relation with slaughter weight. When DMI was expressed per 100 kg of live weight a linear decline occurred (DMI/100 kg W= 3.599 - 0.003152SW) as the final weight increased. Body condition improved linearly with the final weight (Body condtion = 0.159 + 0.0103SW), while feed conversion worsen (FCDM = 1.585 + 0.01019SW), however it can be considered satisfactory, being respectively 5.09, 5.35, 5.55 and 6.04 kg of DM/kg of weight gain. In order to reach the minimum carcass weight and subcutaneous fat thickness required, the regression equation estimation showed that slaughter weight should be of 337 and 327 kg, respectively.

Ingestive behavior of feedlot finished young bulls fed different concentrate levels in the diet

The objective of this trial was to evaluate the carcass quantitative characteristics of two categories: steers and young steers, from two genetic groups, 5/8Charolais (CH) 3/8Nelore (NE) and 5/8NE 3/8CH, and to evaluate the relation among studied variables. The animals were fedlot finished until reaching 430 kg of body weight. Steers were slaughtered averaging 22.8 months old and young steers 15.2 months old. The diet, roughage:concentrate ratio of 60:40 (dry matter basis), contained 10.25% crude protein and 3.18 Mcal of digestible energy/kg of dry matter. The experiment was analyzed as a complete randomized design with six replicates, according to a 2 x 2 (two categories x two genetic groups) factorial scheme. Significant interactions were verified for hot (HDP) and cold (CDP) dressing percentage. 5/8NE 3/8CH young steers showed higher HDP (57.51 vs. 54.10%) and CDP (54.84 vs. 52.62%) than 5/8CH 3/8NE of same category and in relation to 5/8NE 3/8CH steers (55.43 vs. 53.84%, respectively).Young steers showed carcasses with higher subcutaneous fat thickness in mm (6.29 vs. 3.22) and mm/100 kg cold carcass weight (2.71 vs. 1.39), cushion thickness (26.58 vs. 25.17 cm), sidecut percentage (13.45 vs. 11.34) and lower sawcut percentage (50.33 vs. 51.39) than steers. Between genetic groups, 5/8CH 3/8NE animals showed carcasses with higher conformation score (11.00 vs. 10.33 points), and 5/8NE 3/8CH higher leg length (72.46 vs. 69.92 cm), arm length (41.92 vs. 38.46 cm) and forequarter percentage (37.54 vs. 36.43). Carcass conformation was positively correlated with Longissimus dorsi area (r = 0.35), cushion thickness (r = 0.23) and arm perimeter (r = 0.15), and negatively with chilling loss of carcass (r = - 0.35). The correlation coefficient was of 0.55 between subcutaneous fat thickness and sidecut percentage.

Efeito do Grupo Genético e da Heterose nas Características Quantitativas da Carcaça de Vacas de Descarte Terminadas em Confinamento

The objective of this work was to evaluate the production and composition of milk of beef cows of four genetic groups, including Charolais (C), Nellore (N), CN crossbreds daughters of C bulls, and NC crossbreds, daughters of N bulls, maintained on native pasture and submitted to different managements during pre-weaning: supplemented with rice bran (.7% of the body weight) and weaned at 42 or 63 days postpartum, or non supplemented and weaned at 63 days. The cow age varied from 3 to 12 years, being classified as: first calf, young, adult and old cows. The data were submitted to variance analysis, the statistic model included management, cow genetic group, cow age and period effects and the interactions among these factors. Lactose and fat contents were not influenced by the factors studied. There was a significant interaction between cow age and period for milk production and between management and cow age for protein content. Supplemented cows showed higher milk production (3.85 vs 3.25 L/day), total dry extract content - EST (12.18 vs 11.83%) and nonfat dry extract content - ESD (8.75 vs 8.57%). The milk production declined as the lactation period advanced, and the reduction was more accentuated in the non supplemented cows. CN crossbred cows produced more milk (4.17 L/day) than the straigthbreds, not differing from the NC crossbred (3.76 L/day). N cows showed milk production similar to the C cows, respectively, 3.16 and 3.11 L/day. However, N cows milk was of better quality, including protein (3.16 vs 2.86%), EST (12.52 vs 11.46%) and ESD (8.87 vs 8.49%). Adult cows showed higher ESD content, followed by the young cows, first calf and old cows, being 8.86; 8.62; 8.62 and 8.54%, respectively.

Nutritional evaluation of the plant and silage of different sorghum hybrids (Sorghum bicolor, L. Moench)

This study was developed to evaluate the ingestive behavior of beef cattle finished in feedlots with different concentrate levels in the diet. Sixteen bulls fed 22, 40, 59, or 79% of concentrate in the diet were assigned to a complete randomized design, with four replicates each. The supplied diets were isoproteic and the roughage used was corn silage. Data collection was carried out during the finishing period, with a total of six days. The time given to food intake, rumination, the number of bouts per meal and neutral detergent fiber rumination efficiency decreased linearly as the concentrate levels in the diet increased. Idle time increased linearly accordingly to the increment of concentrate in the diet. The animals have greater feed intake and rumination efficiency when fed higher levels of concentrate (79%).