Um estudo sobre a ambivalência materna em mães de crianças com alergia à proteína do leite de vaca

Pós-graduação em Psicologia - FCLAS

Fatores que afetam a taxa de concepção após inseminação artificial ou transferência de embriões em vacas holandesas em lactação

Pós-graduação em Medicina Veterinária - FMVZ

Infecção por Leptospira spp. e Neospora caninum, em rebanho bovino leiteiro: avaliação dos aspectos produtivos e reprodutivos

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

Efeito da radiação solar no comportamento de vacas holandesas em ambiente tropical

Pós-graduação em Zootecnia - FCAV

Studying the distribution of Selenium in buffalo and cow's milk whey

Neste estudo, a cromatografia por exclusão de tamanho (SEC) com detecção online ultravioleta (UV), espectrometria de absorção atômica em forno de grafite (GF AAS) e a espectrometria de massa por tempo de voo com dessorção/ionização de matriz assistida por laser (MALDI-TOF-MS) foram usadas para estudar a associação de selênio com macromoléculas e compostos presentes no soro de leite de búfala e bovino. Os perfis de SEC-UV obtidos para as amostras de soro de leite de búfala e soro de leite bovino indicaram a presença de espécies de alta e baixa massa molecular. A combinação das informações obtidas com SEC-UV, GF AAS e MALDI-TOF-MS para as frações < 10 kDa confirmou a associação de selênio com espécies de baixa massa molecular.

Persistência da lactação e Influência da estrutura de dados sobre a estimação de parâmetros genéticos para a produção de leite de bovinos da raça Holandesa

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Derivados da extração do óleo de girassol para vacas leiteiras

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Fatores limitantes do consumo de capim-elefante cv. Napier utilizando vacas leiteiras confinadas

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

Avaliação das características do líquido ruminal, hemogasometria, atividade pedométrica e diagnóstico de laminite subclínica em vacas leiteiras

The objectives of this study were to evaluate the characteristics of ruminal fluid, blood gas analysis, pedometer activity and suclinical laminitis occurrence, through the presence of secondary foot diseases in high production dairy cows, from a commercial herd. 200 Holstein cows originating from the same farm, located in Araçatuba/SP, Brazil, were divided into four groups, which are established from the daily milk production. Initially clinical examination of the cows was procedure, followed by sampling of rumen fluid, by esophageal tube. Fluid was evaluated for pH, color, odor, consistency, sedimentation, flotation and methylene blue reduction test. Venous blood samples were also collected for blood gas analysis, in addition to collecting data from pedometrics (number of steps) and daily milk production. Data were tabulated and submitted to correlation analysis. No animal had reported changes in rumen pH. Non-acid base imbalance were found, since the values of blood pH, PCO2, TCO2, HCO3- and BE were normal during hemogasimetric analysis. The pedometric was effective as a screening method to cows with foot diseases. It demonstrated reduction in the number of steps due to pain, correlated with lower milk production. However, the identification of foot lesions was only possible through specific digital clinical examination. The occurrence of 49.5 % of herd foot problems was due to the risk factors present in the farm. The abrasive concrete and inadequate facilities, also associated with the possible occurrence of sub-acute ruminal acidosis, were observed as risk factors. However, sub-acute ruminal acidosis was undiagnosed by the methods used. The correlation between the values of ruminal pH, and blood gas analysis pedometrics showed efficient for the early diagnosis of foot diseases and also in establishing the etiology of these diseases. Subclinical laminitis occurred primarily in cow's herd, considering the multifactorial etiology of this disease, occurrence and distribution of foot diseases diagnosed.

Reproductive parameters of dairy goats submitted to estrus synchronization with prostaglandin F2α associated or not to hCG at estrous onset

O objetivo deste estudo foi avaliar a eficiência do uso de duas doses de PGF associadas ou não à administração de hCG no início do estro sobre os parâmetros reprodutivos de cabras leiteiras. Um total de 29 cabras receberam duas doses de 30 µg d-cloprostenol pela via latero-vulvar com 10 dias de intervalo (Dia 1 e Dia 10). As cabras foram alocadas para receberem o hCG (250 IU) ou salina i.m. no momento em que o estro foi detectado. Depois da realização da segunda dose de PGF, o estro foi monitorado e exames ultrassonográficos foram realizados duas vezes ao dia. Todas as fêmeas foram inseminadas 16 h após o inicio do estro. Amostras de sangue foram coletadas diariamente para determinação das concentrações plasmáticas de progesterona. O uso do hCG no momento do início do estro não afetou os parâmetros estudados e, portanto, os dados serão apresentados agrupados. A taxa de manifestação de estro foi similar (P > 0,05) na primeira (75,9% - 22/29) ou na segunda dose de PGF (79,3% - 23/29). O intervalo entre a administração de PGF e o início do estro foi maior (P < 0,05) no Dia 1 (75,8±53,9 h) que no Dia 10 (47,7±10,1 h). Duração do estro também diferiu (P < 0,05) 35,4±15,9 (Dia 1) vs 26,8±15, 0 h (Dia 10). A taxa de ovulação foi 79,3% (23/29) após a segunda dose PGF. Não foi encontrada diferença (P>0,05) entre os grupos experimentais quanto aos parâmetros reprodutivos: intervalo entre a aplicação da segunda dose e a ovulação (86,6±11,4h), intervalo do estro a ocorrência da ovulação (39,9±12,3h), diâmetro do maior folículo (7,2±1,4) e número de ovulações (1,8±0,6). No Dia 1, 52,4% (11/21) apresentavam concentrações de progesterona < 1 ng/mL. No Dia 10, 100% dos animais apresentavam concentrações >1ng/mL. O presente estudo permite concluir que o estro pode ser eficientemente sincronizado em cabras leiteiras com duas doses de PGF intervaladas em 10 dias. Novas pesquisas devem se realizadas para avaliar diferentes doses e momentos de utilização do hCG.

Nutrient intake, productive performance and body measurements of dairy heifers fed with different sources of protein

This study evaluated the effect of different protein sources (soybean meal, cottonseed meal, peanut meal and sunflower meal) on dry matter and nutrient intake, productive performance and body measurements of dairy heifers, Holstein x Zebu, recreated in confinement. The experiment consisted in a randomized complete block design made up by 6 replications and 4 treatments. The mean values of ingestion of ether extract (EEI, kg day-1) were statistically different (p < 0.05). The neutral detergent fiber intake (NDFI, %BW) also presented differences (p < 0.05), with higher values in the diet containing sunflower meal (1.01% BW) in relation to the diet with soybean meal (0.84% BW). The average daily weight gain using the diet with soybean meal was superior (0.95 kg day-1) to the diet with sunflower meal (0.82 kg day-1), and considering the final body weight, the diet with soybean meal was superior to the other treatments (p < 0.05). The heart girth presented greater association with body weight (0.93). The soybean meal promoted the best productive performance of crossbred Holstein x Zebu heifers fed diets based on sugarcane. However, cottonseed meal, peanut meal and sunflower meal can be possible alternatives to soybean meal.

Risk factors for anaplasmosis in dairy cows during the peripartum

Anaplasma marginale is endemic in tropical and subtropical areas around the world. Some studies have suggested that cows during peripartum may present a transient immunosuppression state and development of clinical signs of anaplasmosis. The aim of this study was to investigate the relationship between some risk factors and the seroprevalence of A. marginale in dairy cows during peripartum in Rio de Janeiro, Brazil. The risk factors analyzed in association with the prevalence of antibodies against A. marginale in dairy cows were calving season, reproductive experience, breed standard, tick infestations, stocking density, and milk yield. The antibodies against A. marginale were tested in indirect enzyme-linked immunosorbent assays. A primary screening using a 2 x k contingency table of the exposed variables with the outcomes was performed. All variables for which p < 0.20 were included in a fixed effects log regression. The risk factors investigated to anaplasmosis were calving (OR 2.61, IC 1.08-7.63), breed standard (OR 3.83, IC 0.08-0.28), reproductive experience (OR 33.7, IC 2.14-5.16), milk yield (OR 3.9, IC 2.24-7.03), Rhipicephalus microplus infestations (OR 10.3, IC 0.05-0.17), and stocking density (OR 22.3, IC 0.05-0.17). Low titers of antibodies against A. marginale during peripartum had been characterized as a period previous to development of clinical anaplasmosis. Thus, studies on anaplasmosis should consider each farm as an epidemiological unit, where environmental and immunological factors may influence the endemic status of the pathogen.

Effects of supplementation of calcium salts of polyunsaturated fatty acids on serum concentrations of progesterone and insulin of pregnant dairy cows

Forty-five non-lactating, pregnant Holstein animals (18 heifers and 27 multiparous cows; BW = 561 +/- 114 kg; BCS = 2.9 +/- 0.3; days pregnant = 110 +/- 56 d) were stratified by initial BW and BCS, and randomly assigned to receive daily (as-fed basis) 0.50 kg of ground corn plus 0.22 kg of kaolin (CON), calcium salts of saturated fatty acids (SFA) or polyunsaturated fatty acids (PF) for 14 d. Blood samples were collected on days 0, 7 and 14, immediately prior to (0 h) and 3, 6, 9 and 12 h after feeding, to determine the serum concentrations of P 4 and insulin. No treatment effects were detected for serum concentrations of P 4 (5.52, 6.13 and 5.63 +/- 0.41 ng/mL for CON, SFA and PF, respectively). No treatment effects were detected for serum concentrations of insulin (11.5, 10.5 and 10.1 +/- 1.43 mu IU/mL for CON, SFA and PF, respectively). Heifers had greater serum concentrations of P 4 than multiparous cows (6.35 vs. 5.16 +/- 0.42 ng/mL), but lower serum concentrations of insulin (7.0 vs. 14.4 +/- 1.49 mu IU/mL). Feeding 0.22 kg of calcium salts of polyunsaturated fatty acids is not sufficient to increase the serum concentrations of P 4 and insulin of non-lactating, pregnant dairy cows.