A comparative study of the efficiency of a pro-biotic and the anti-K99 and anti-A14 vaccines in the control of diarrhea in calves in Brazil.

A total of 99 pregnant cows were divided into eight groups submitted to the following treatments: group I (n = 29) consisted of unvaccinated cows whose calves did not receive a probiotic and was used as control. Group II (n = 10) consisted of vaccinated cows whose calves did not receive a probiotic. Groups III, IV and V (n = 10 neach) consisted of vaccinated cows whose calves received a probiotic for 5, 15 and 30 days, respectively. Groups VI, VII and VIII (n = 10 each) consisted of unvaccinated cows whose calves received a probiotic for 5, 15 and 30 days, respectively. Each animal in the vaccinated groups received two 5.0 ml vaccine doses containing pili K99 and A14 of Escherichia coli by the subcutaneous route. The probiotic containing Lactobacillus acidophilus at the dose of 2.0 x 10(8) live cells in 250 ml milk, was administered orally. All animals were observed clinically and bacteriologically and anti-K99 and anti-A14 antibody titers were determined in serum and colostrum. Mean calf weight was measured at birth and at 30 days of age. The results showed that a combination of the vaccine with the probiotic administered for 15 and 30 days was the most efficient treatment for the control of diarrhea.

Torta de dendê em dieta para a tilápia-do-nilo: Desempenho produtivo

To evaluate the nutritional value of African palm kernel meal (Elaeis guineensis) on the performance of Nile tilapia (Oseochromis niloticus), five isonitrogenous (30% crude protein), isoenergetic (2,800 Kcal/kg of digestible energy), and isofibrous (10% crude fiber) diets, with increasing levels of African palm kernel meal (0, 7, 14, 21, 28 and 35%) were fed ad libitum for 18 weeks to Nile tilapia (Oreochromis niloticus) fingerlings, averaging 1.52 ± 0.04 g of body weight, housed for 120 days in 60 liter aquaria with six fingerlings. To determine the production traits, weight gain, apparent food conversion, specific growth rate, protein efficiency ratio, weight gain percentage, net protein utilization, and body composition, fish were weighted at six-week intervals. Statistical analysis of recorded data were performed through multivariate profile analysis and polynomial regression models. Results showed that feeding fingerling Nile tilapia with ratios containing up to 35% of African palm kernel meal does not affect production performance.

Two-Way Selection for Daily Gain and Feed Conversion in a Composite Rabbit Population

We conducted a two-way selection experiment in a composite rabbit population to investigate the responses to selection for postweaning ADG and feed conversion (FC). Two generations of crossing, followed by four generations of random pair matings, preceded three generations of selection. Selection was practiced within four lines: high-feed conversion (HFC), low-feed conversion (LFC), high gain (HG), and low gain (LG). Data on 1,446 rabbits from the random mating and selection generations were fitted to an animal model to estimate heritabilities of and the genetic correlation between ADG and FC. The two-trait model included rabbit and common litter random effects and line, generation, and sex fixed effects. Estimates of heritability of ADG and FC were .48 and .29, respectively, and the genetic correlation between them was -.82. Common litter environmental effects accounted for a proportion of .11 and . 13 of the phenotypic variation of the two traits, respectively. For ADG (in g/d) the regressions of mean breeding values on generation number during the selection period were 1.23 ± .12 (P < .01) in the HG line and -.86 ± .12 (P < .01) in the LG line; the regressions for FC (in g feed/g gain) were -.07 ± .01 (P < .01) in the HFC line and .03 ± .01 (P < .05) in the LFC line. Selection for ADG was effective in improving ADG and FC.

Efeito da somatotropina bovina recombinante no desempenho e nas características químicas da carne de bovinos

The objective of this study was to evaluate the effects of the use of recombinant bovine somatotropin (rbST) in weight gain, feeding efficiency and chemical characteristics of meat of young bulls. Fifty nine young bulls were used: 30 crossbred Simmental x Nelore and 29 Nelore aging between seven to eight months, weighing 236 and 116 kg, respectively. A randomized experiment in a 2 × 2 factorial arrangement was used. There were two levels of rbST (0 and 250 mg/animal/14 days) and two breed groups subdivided in two experimental phases. Diet was based on corn silage and concentrate aiming at a weight gain of 0.8 a day for Phase I (70 days) and 1.3 kg for Phase II (98 days). Animals were slaughtered at 13 months of age and the measurements of carcass dressing and meat quality were taken. Results showed that cross-breeding animals overcame (p<.01) the Nelore breed in weight gain and final weight at slaughtering. Use of rbST has not influenced weight gain, final weight, carcass weight and chemical characteristics of meat (p>.05). The use of rbST improved feeding efficiency 11.91 % for cross-bred and 24.32% for Nelore in Phase II.

Exigências de proteína para frangas de postura de 1 a 18 semanas de idade

The objective of this experiment was to determine the protein requirements for hen pullets from 1 to 18 weeks of age, by factorial method, using the nitrogen balance and the comparative slaughtering techniques. Protein requirements for maintenance, was obtained by the nitrogen balance technique using four diets with different protein levels (18,9, 4 and 2% of CP) aiming to obtain positive balance, next to zero and negative nitrogen balance. The endogenous nitrogen losses (0.2575 g of N/kg·75/day) was obtained by regression of nitrogen balance (NB) on ingestion nitrogen (IN). The requirements of nitrogen for maintenance was estimated by the intercept of axis X (0.3831 g of N/kg·75/day). The slope of the straight line still supplied the efficiency of N of the diet (67.21%). The regression coefficients of the equation represented the requirements of net nitrogen for weight gain. Considering the conversion efficiencies of nitrogen of the diet into nitrogen for weight gain, the requirements of nitrogen were determined for weight gain of .065, .087g and .090 g of N per gram of weight gain, for the phases 1 to 6, 7 to 12, and 13 to 18 weeks of age, respectively. Based on the results, three equations of prediction of the daily nitrogen requirements were fitted in function of live weight (LW in kg) and daily weight gain (G in g): 1 to 6 weeks N=.3831 x BW·75 + G .065, 7 to 12 weeks N=.3831 × BW·75 + G .087, and 13 to 18 weeks N=.3831 × BW·75 + G .090.

Efeitos da restrição alimentar no desempenho de bovinos jovens confinados

The objective of the study was to evaluate compensatory weight gain in the performance of young bulls submitted to feed restriction, in the initial phase of confinement and to study the economic viability of the utilization of three protein sources. Sixty six crossbred bulls Simental-Nelore, eight months old and averaging 220 kg of weight were submitted to three feeding programs in the growth phase that lasted 84 days. The feeding programs were ad libitum, restriction + raw soybean grains and restriction + toasted soybean grains, with a restriction level of 25% on average. In the finishing phase, with a 61 day duration, animals fed with each of the three diets mentioned above received two types of supplementary diets: raw soybean grains and poultry litter. There were no differences between final weights of animals in finishing phase, but the bulls submitted to the restriction had more weight gain per day and better food conversion than ad libitum animals, for both raw soybean grains and poultry litter. The conclusion was that the feeding restriction and consequent compensatory weight gain, presented advantages for feeding efficiency, by decreasing maintenance requirements, although final cost had been equivalent to ad libitum animals.

A low-voltage triode-MOSFET four-quadrant multiplier with optimized current-efficiency

A low-voltage, low-power four-quadrant analog multiplier with optimized current-efficiency is presented. Its core corresponds to a pseudodifferential cascode, gain-boosting triode-transconductor. According to a low-voltage 1.2μm CMOS n-well process, operand differential-amplitudes are 1.0Vpp and 0.32Vpp for a 1.3V-supply. Common-mode voltages are properly chosen to maximize current-efficiency to 58%. Total quiescent dissipation is 260μW. A range of PSPICE simulation supports theoretical analysis. Excellent linearity is observed on dc characteristic. Assuming a ±0.5% mismatch on (W/L) and VTH THD at full-scale is 0.93% and 1.42%, for output frequencies of 1MHz and 10MHz, respectively.

Modeling metabolizable energy utilization in broiler breeder pullets

The objective of this study was to determine models for ME requirements for broiler breeder pullets using the factorial method. The influence of the temperature on maintenance ME requirements was determined by experiments conducted in three environmental rooms with temperature kept constant at 15, 22, and 30°C, using the comparative slaughter technique. The energy requirements for weight gain were determined based on the body energy content and efficiency of energy utilization for weight gain. Two ME requirement models for each age were developed using the coefficients for maintenance and weight gain. The models for 3 to 8 wk were ME = W 0.75 (186.52 - 1.94T) + 2.47WG, and ME = W 0.75 (174 - 1.88T) + 2.83WG; for 9 to 14 wk, ME = W 0.75 (186.52 - 1.94T) + 2.69WG, and ME = W 0.75 (174 - 1.88T) + 2.50WG; and 15 to 20 wk, ME = W 0.75 (186.52 - 1.94T) + 2.76WG, and ME = W 0.75 (174 - 1.88T) + 3.24WG. In these equations, W is BW (kg), T is temperature (°C), and WG is daily weight gain (g). These models were compared to the breeder's recommendations in a feeding trial from 5 to 20 wk of age. Models 1 and 2 provided energy intakes that promoted BW smaller than the breeder's recommendation. However, all breeder pullets had weights above the standard recommendation. Model 2 gave the smallest ME intake and BW close to the standard recommendation and provided the best prediction of ME requirements.

Desempenho e características da carcaça de tourinhos santa gertrudes confinados, recebendo dietas com alto concentrado e níveis crescentes de polpa cítrica peletizada

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Bone mineralization among male adolescents: Critical years for bone mass gain

Objective: To verify the behavior of the mineral bone content and density in male adolescents according to age and secondary sexual characters. Methods: 47 healthy adolescents between 10 and 19 years old were assessed according to weight, height, body mass index, puberty stage, calcium intake, bone mineral density and content in the lumbar spine and in the proximal femur. The bone mass was measured through bone densitometries. The intake of calcium was calculated through a 3-day diet. The BMI (body mass index) was calculated with the Quetelet Index and the puberty stage was defined according to Tanner's criteria. The analysis used descriptive statistics such as average and standard deviation, and variance estimates to compare the different age groups. Moreover, the Tukey test was used to determine the significant differences. Results: It was evident that the calcium intake in the different ages assessed has not reached the minimum value of 800 mg. The bone mineral density and content showed an increase after the age of 14, as well as when the teenagers reached the sexual maturation stage G4. The mineralization parameters showed a high level when the teenagers were in the G3 stage, however, without statistical significance. Conclusion: The results indicate an important level of bone mineralization during adolescence. Maturation levels superior to G3 have shown more mineralization. This study proves that the critical years for bone mass gain start after the 14-15 years old or older. Copyright © 2004 by Sociedade Brasileira de Pediatria.

The influence of dietary vitamin C and E supplementation on the physiological response of pirarucu, Arapaima gigas, in net culture

This study evaluated the efficacy of dietary vitamin C (ascorbic acid or AA), vitamin E (α-tocopherol or α-T), and C + E supplementation on the blood parameters of Arapaima gigas grown in net cages for 45 days. Four treatments were tested: control (commercial feed); C800; E500 and C + E (800 + 500) with supplementation of 800 mg AA kg- 1, 500 mg α-T kg- 1 and 800 + 500 mg AA + α-T kg- 1, respectively. Hematocrit (Ht), red blood cells (RBC), and hemoglobin concentration (Hb) (oxidative status indicators), thrombocytes and leukocytes (immunological indicators), plasma protein and glucose were evaluated. Fish fed vitamin C and C + E supplemented diets showed greater weight gain and survival. Dietary vitamin C and C + E diet supplementation resulted in increased Ht, Hb, RBC, MCHC, total leukocytes, total proteins, thrombocytes and eosinophils compared to the control and α-T. The α-tocopherol-supplemented diet reduced the number of total thrombocytes, lymphocytes and neutrophils and increased glucose and eosinophils relatively to the control. In general, leukocytes and thrombocytes were good indicators of the efficiency of vitamin on the defense mechanism of the A. gigas reared in cages. Results indicate that high α-T diet supplementation provides no benefit for the maintenance of the oxidative or the immunological status of A. gigas. However, it was demonstrated that high dietary AA improves A. gigas immunological status. Red blood cell indices and immune system indicators showed no synergistic effect between the vitamins after supplementing the A. gigas diet with α-T + AA. © 2006 Elsevier Inc. All rights reserved.

Modulation of insulin secretion by physical training during recovery from protein malnutrition in rats

Objective: The purpose of the present study was to examine insulin secretion in rats submitted to protein restriction and nutritional recovery associated or not to physical training. Methods: The experiment was designed in two sets of five weeks each. In the first set the rats were fed a nonnal-protein diet(17%-control group) or a low-protein diet (6%-malnourished group) for five weeks. After this, all animals were fed the 17% protein diet and separated into four groups: sedentary control(SC); trained eontrol(TC); sedentary recovered(SR) and trained recovered(TR). TC and TR rats performed swimming exercise. Results: The results indicated efficiency of the 6% protein diet in producing signs of malnutrition, as reduction in body weight gain and serum albumin levels, as well as liver fat. Serum insulin in the fed state and insulin secretion by isolated pancreatic islets in response to glucose were Keduced,but peripheral sensitivity to insulin was increased and glucose tolerance was not changed in the protein deficient rats, indicating adaptation to malnutrition. Diet protocol for nutritional recovery was efficient in repairing body weight gain, serum albumin and liver fat levels of the previously malnourished rats. Glucose induced insulin release by pancreatic islets remained low after nutritional recovery. Insulin secretion by the islets isolated from rats submitted to exercise training during nutritional recovery was improved when compared with the sedentary animals. Conclusion: This indicates that exercise training may be useful in the treatment of protein calorie malnutrition, concerning to glucose induced insulip secretion.

Treatments to optimize the use of artificial insemination and reproductive efficiency in beef cattle under tropical environments

Bos indicus cattle, the preferred genetic group in tropical climates, are characterized by having a lower reproductive efficiency than Bos taurus. The reasons for the poorer reproductive efficiency of the Bos indicus cows include longer lengths of gestation and postpartum anestrus, a short length of estrous behavior with a high incidence of estrus occurring during the dark hours, and puberty at older age and at a higher percentage of body weight relative to mature body weight. Moreover, geography, environment, economics, and social traditions are factors contributing for a lower use of reproductive biotechnologies in tropical environments. Hormonal protocols have been developed to resolve some of the reproductive challenges of the Bos indicus cattle and allow artificial insemination, which is the main strategy to hasten genetic improvement in commercial beef ranches. Most of these treatments use exogenous sources of progesterone associated with strategies to improve the final maturation of the dominant follicle, such as temporary weaning and exogenous gonadotropins. These treatments have caused large impacts on reproductive performance of beef cattle reared under tropical areas. Copyright © 2011 O. G. Sá Filho and J. L. M. Vasconcelos.

Risk factors for low birth weight in Botucatu city, SP state, Brazil: A study conducted in the public health system from 2004 to 2008

Background: Low birth weight (LBW), defined as birth weight less than 2500 g, has a complex etiology and may be a result of premature interruption of pregnancy or intrauterine growth restriction. The objective of this study was to provide information on determinants of LBW and contribute to the understanding of the problem in Brazil. Methods. A case-control study was conducted in Botucatu city, SP state, Brazil. The study population consisted of 2 groups with 860 newborns in each group as follows: low weight newborns (LWNB) and a control group (weight ≤ 2500 g). Secondary data from 2004 to 2008 were collected using the Live Birth Certificate (LBC) and records from medical charts of pregnant women in Basic Health Units (BHU) and in the Public University Hospital (UH). Variables were as follows: maternal socio-demographic characteristics, pregnancy and birth conditions including quality of prenatal care according to 3 criteria. They were based on parameters established by the Ministry of Health (MH), one of them, the modified Kessner Index. The multivariable analysis by logistic regression was used to evaluate the association between variables and LBW. Results: According to the analysis, the factors associated with LBW were as follows: prematurity (OR = 56.98, 95% CI 29.52-109.95), twin pregnancy (OR = 20.00, 95% CI 6.25-100.00), maternal smoking (OR = 2.12, 95% CI 1.33-3.45), maternal malnourishment (OR = 2.30, 95% CI 1.08-5.00), maternal obesity (OR = 2.30, 95% IC 1.18-4.48), weight gain during pregnancy less than 5 kg (OR = 2.63, 95% CI 1.35-5.00) and weight gain during pregnancy more than 15 kg (OR = 2.26, 95% CI 1.16-4.41). Adequacy of prenatal care visits adjusted to gestational age was less frequent in the LBW group than in the control group (68.7% vs. 80.5%, x 2 p < 0.001). According to the modified Kessner Index, 64.4% of prenatal visits in the LWNB group were adequate. Conclusion: LWNB are a quite heterogeneous group of infants concerning their determinants and prevention actions against LBW and the follow-up of these infants have also been very complex. Therefore, improvement in the quality of care provided should be given priority through concrete actions for prevention of LBW. © 2012 Fonseca et al; licensee BioMed Central Ltd.

Genetic correlations between mature cow weight and productive and reproductive traits in Nellore cattle

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)