Severino Benone Paes Barbosa

Estimativas de parâmetros de curvas de crescimento de bovinos Zebu, criados no estado de Pernambuco

Foram analisados dados de pesagem constantes no banco de dados de Controle de Desenvolvimento Ponderal da Associacao Brasileira de Criadores de Zebu (ABCZ), referentes a 24.028 animais Zebu das racas Guzera, Nelore e Nelore Mocho, nascidos entre 1960 e 2000, objetivando-se estimar parâmetros de curvas de crescimento por meio de equacoes nao-lineares e verificar a influencia de efeitos fixos e aleatorios sobre as estimativas. As pesagens ocorreram ao nascimento e em intervalos de 90 dias ate dois anos de idade. Para analise dos dados de peso-idade, foram utilizados os seguintes modelos nao-lineares: Brody, Gompertz, Logistico, Mitscherlich, von Bertalanffy, Richards e Logistico duplo. As fontes de variacao estudadas no modelo misto foram sexo, propriedade, ano e mes de nascimento, tipo de sistema de criacao e interacao sexo*sistema de criacao, como efeitos fixos, e reprodutor e mae, como efeitos aleatorios. A equacao Logistica Dupla foi a que apresentou o melhor ajustamento e a Mitscherlich, o pior, segundo o numero de convergencias e o indice de ajuste. Os efeitos fixos mais influentes foram sexo, propriedade, ano e mes de nascimento e sistema de criacao. O efeito aleatorio mais influente foi o de mae. A variabilidade encontrada pode possibilitar a exploracao da modificacao da curva de crescimento por meio de programas de melhoramento genetico.

Tamanho da leitegada e pesos médios, ao nascer e aos 21 dias de idade, de leitões da raça Large White

The effects of season of birth (PE) and age of sow at birth (IMP) on litter size (TL); season of birth, age of sow and litter size on average weight at birth (PMN); season of birth age of sow, number of alive piglets at birth (NV), and percentage of alive males on average weight at 21 days of age (PM21) of 3259 Large White piglets born from June/85 to June/96 were evaluated by multiple regression analyses. The IMP effect on TL was significant. The average TL was 9.73±2.78. Larger litters were observed for sows from 2.84 to 3.83 years of age. The average PMN and PM21 were 1.35kg±0.18 e 5.06kg±1.00, respectively. The IMP and TL effects on PMN traits were linear and significant. A decrease of 20g on piglet weight was estimated for each additional piglet in the litter. The effect of NV was significant only for PM21 trait.

Produção de geléia real e desenvolvimento da larva de abelhas Apis mellifera, na região semi-árida de Pernambuco

Foram analisados dados de producao de geleia real (GR) e peso da larva (PL), em dois apiarios nos municipios de Ibimirim e Petrolândia, na regiao semi-arida do Estado de Pernambuco, nos meses de junho e agosto de 1995, para avaliar o momento de maior acumulo de GR, nas celulas reais (realeiras), e acompanhar o desenvolvimento da larva. O delineamento experimental foi o de blocos casualizados. A quantidade de GR acumulada nas realeiras foi avaliada 24, 32, 48, 56 e 72 horas apos a transferencias das larvas. As analises de variância mostraram efeitos significativos para o tempo de permanencia, afetando a producao de GR e o PL, nos dois locais estudados. Foi feito um desdobramento polinomial do efeito de tratamento para se avaliar o momento de maior producao de GL. De acordo com as equacoes de regressao obtidas, as producoes maximas ajustadas de 175,57 mg (Ibimirim) e 183,69 mg (Petrolândia) foram conseguidas com 59 e 54 horas apos a transferencia das larvas, respectivamente. De acordo com os resultados obtidos, concluiu-se que, em ambos os locais, maiores producoes de GR poderao ser obtidas fazendo-se coletas entre 48 e 56 horas apos a transferencia das larvas. Apos esse periodo, o crescimento da larva e intensificado pelo aumento de consumo de geleia, reduzindo-se a quantidade de GR acumulada nas realeiras.

Milk and fat production of crossbred Holstein-Gir cows (Bos taurus taurus-Bos taurus indicus) in the agreste region of the Brazilian state of Pernambuco

The productive performance of four Holstein-Gir genetic groups (1/2H, 1/4H, 5/8H, 5/8Hinter se) and the effects of non-genetic factors on production traits was evaluated using a data set of 7,951 test-day samples collected between January 1980 and December 1999 from the Arcoverde Experimental Station in the Brazilian state of Pernambuco (Empresa Pernambucana de Pesquisa Agropecuaria). The statistical model included the fixed effects of calving year (1980 to 1999) and month (January to December), genetic group of the cow, age at months of calving (33 to 190) and days in milk at each test-day. Random effects were sire, cow and residual with test-days treated as repeated records within each cow within each lactation. For the four genetic groups the milk yield (MY) means were 1/2H = 8.61 kg ± 1.16 kg, 1/4H = 5.34 kg ± 0.46 kg, 5/8H = 7.42 kg ± 0.39 kg and 5/8Hinter se = 5.76 kg ± 0.46 kg; the fat yield (FY) means were 1/2H = 0.375 kg ± 0.052 kg, 1/4H = 0.231 kg ± 0.026 kg, 5/8H = 0.299 kg ± 0.025 kg and 5/8Hinter se = 0.231 kg ± 0.026 kg; and the fat percentage (FP) means were 1/2H = 4.45 kg ± 0.29%, 1/4H = 4.08 kg ± 0.12%, 5/8H = 3.87 kg ± 0.10% and 5/8Hinter se = 3.89 kg ± 0.12%. Phenotypic correlations between tests were MY = 0.97, FY = 0.94 and FP = 0.98. The best productive performance was for the 1/2H group, followed by the 5/8H group. The performance of the synthetic group was substantially below the performance of the 5/8H group.

Uso de funções de covariância na descrição do crescimento de bovinos Nelore criados no estado de Pernambuco

Random regression models using Legendre polynomials were used to describe the growth curve of Nelore cattle weighted every three months from birth to 720 days of age, in Pernambuco state, northeastern Brazil. Six different random regression models using Legendre polynomials of three, four, and five degrees to model additive genetic and permanent environmental effects, under homogeneous and heterogeneous residual variances with three classes were evaluated. According to the Akaikes information criteria, the five degree Legendre polynomial with homogeneous error was the best fitting model. Genetic and phenotypic correlations were low between weights at early and late stages of the weighting period, and high and approximately constant between weights at late stages. Genetic covariance of weights increased with age. Heritability estimates were low to moderate up to 60 days of age and reached values between 0.50 and 0.60 at older ages.

Herdabilidades de parâmetros de curvas de crescimento não-lineares em zebuínos, no estado de Pernambuco

Objetivou-se estimar parâmetros geneticos e fenotipicos de curvas de crescimento de modelos nao-lineares. Foram analisados dados de pesagem constantes no banco de dados de Controle de Desenvolvimento Ponderal da Associacao Brasileira de Criadores de Zebu (ABCZ), referentes a 24.028 animais Zebu, nascidos entre 1960 e 2000, das racas Guzera, Nelore e Nelore Mocho. As pesagens ocorreram ao nascimento e em intervalos de 90 dias ate dois anos de idade. Os seguintes modelos nao-lineares foram utilizados na analise dos dados de peso-idade: Brody, Gompertz, Logistico, von Bertalanffy e Richards. Os efeitos fixos estudados no modelo misto foram sexo, rebanho, ano e mes de nascimento e regime de criacao. As herdabilidades para os parâmetros foram de baixa a alta magnitude, em geral, para todos os modelos. As correlacoes geneticas entre peso assintotico e taxa de maturidade e entre peso assintotico e velocidade de crescimento foram negativas, enquanto aquelas entre taxa de maturidade e velocidade de crescimento foram positivas. As correlacoes fenotipicas foram negativas entre peso assintotico e taxa de crescimento e entre peso assintotico e velocidade de crescimento e positivas entre taxa e velocidade de crescimento. Encontrou-se variabilidade possivel de ser explorada em um programa de melhoramento genetico, especialmente para a raca Nelore, que apresentou amostra de dados e resultados mais consistentes.

Comportamento, produção e qualidade do leite de vacas Holandês-Gir com climatização no curral

Objetivou-se, com este trabalho, avaliar o tempo de exposicao dos animais ao sistema de resfriamento adiabatico evaporativo no curral de espera sobre as variaveis meteorologicas (temperatura e umidade relativa do ar), comportamento animal, producao e aspectos qualitativos do leite de vacas Girolando, utilizando-se 16 vacas multiparas de composicao genetica 7/8 Holandes-Gir em lactacao, com producao media de 18 kg de leite animal-1 d-1. O delineamento experimental utilizado foi o quadrado latino 4 a - 4. O experimento teve duracao de 56 dias, realizado durante o periodo de verao. Os tratamentos corresponderam aos intervalos de 10, 20 e 30 min de exposicao a climatizacao e controle, sendo que o tempo de 30 min de exposicao ao sistema possibilitou condicionamento termico na segunda ordenha (turno da tarde), proporcionando aumento na producao de leite na ordenha seguinte de 0,640 kg animal-1. Verificou-se maior percentual de tempo despendido com a ingestao de alimentos e ruminacao (17,31 e 30,19%) no tratamento 30 min, comparativamente ao controle (15,50 e 27,37%), respectivamente. Nao se verificou efeito significativo na composicao do leite, entre os tratamentos.

Modelos de predição da natimortalidade em suínos

A total of 335 records of swine litters from 102 Large White females that farrowed between 1985 and 1996, born in the seasons of september to february and march to august, in the Recife city, in Pernambuco state (Brazil), were analysed. The objective was to compare regression equations to predict stillborn rates. Angular transformation (TA), a generalized linear model (GLM) with binomial distribution and logit link (BL), a Poisson GLM with log link (PL), a mixed GLM (GLMM) with binomial distribution and logit link (BLM) and a Poisson GLMM with log link were compared. Were considered the following sources of variation: average weight of piglets at birth in kilograms (P), age of the mother at birth in years (I), number of males (M) and females (F) born. Selection criteria for best model were prediction capacity and residual analysis. The best model was the GLM with binomial distribution with logit link with de variables age of the mother, number of males, and number of females.

Qualidade do leite cru refrigerado sob inspeção federal na região Nordeste

The aim was to study seasonal influence on the chemical composition, somatic cell count (SCC) and total bacteria count (TBC) in bulk tank milk in the Brazilian Northeast. The data analyzed was obtained from 116.989 samples of bulk tank milk collected from industries that have an account at the Federal Inspection Service (FIS). The samples were separated into three periods (I,II,III), according to application of IN-51. PROC GLM was used to study the comparison of means by Duncans test. The fat varied more, with an average of 3.66%, protein and lactose had an amplitude of 0.04% between periods, and an average of 3.16 and 4.41%, respectively. Higher values of SCC were observed in the months from May to July (594.33 to 625.28 thousand cells/mL), while in TBC the largest values occurred in May and June (1308.54 and 1333.83 CFU/mL). Significant differences in milk components between states were observed, especially with regard to hygienic quality. The chemical composition, SCC and TBC were influenced between periods and months of the year.

Eficiência reprodutiva e influência de fatores de meio e de herança sobre a variação no peso ao nascer de bubalinos no estado de Rondônia

The objectives of this study were to evaluate reproductive traits (age at first calving and calving interval) and to obtain heritability estimates for birth weight in a crossbred (Murrah and Mediterranean breeds) Buffalo population in Rondonia State, Brazil. Data recorded between 1979 and 2001 were analyzed by SAS®. Variance components and heritability estimates were obtained by using the DFREML program. Age at first calving (1,291 ± 235 days) was significantly influenced by the contemporary group of dam. Calving interval (451 ± 139 days) was significantly influenced by the fixed effects of contemporary group of dam, weight of dam at previous calving, linear and quadratic components of age of dam at previous calving and the random effect of dam. Birth weight (34.25 ± 5.02 kg) was influenced by the fixed effects of sex, contemporary group of calf, weight of dam at calving and by the random effect of dam. Heritability estimate for birth weight was high (0.60 ± 0.12), suggesting genetic gains may be obtained by selection for birth weight in this Buffalo population.