Nutritional value of high moisture corn silage in the diet of Holstein cows

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

Deforming mandibular osteomyelitis in a cow caused by Trueperella pyogenes

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

Retenção de placenta no proteinograma de vacas Holandesas

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

Physiological and production response of dairy goats bred in a tropical climate

The aim of this work was to determine the adaptability of Saanen and A1/2Saanen x A1/2Anglo-Nubian (A1/2SA1/2AN) goats bred in tropical climates. The study included 30 goats, 15 Saanen and 15 A1/2SA1/2AN. The data was collected during the rainy and dry seasons. During the whole experimental period, the environment variables were recorded, as well as rectal temperature (RT), superficial temperature (ST), respiratory rate (RR) and heart rate (HR) and milk production (MP). The adaptability coefficient (AC) was calculated for both genotypes. The averages were evaluated by ANOVA at 5 % probability. There was a genotype and period of year effect, as well as the interaction genotype x period of year. Pearson's simple correlation analysis was then carried out between milk production and physiological and environment variables. There was a statistical difference (p < 0.05) between the seasons for RT, ST and RR. RT, RR and HR were lower for A1/2SA1/2AN than Saanen goats, regardless of the season. MP was greater in the dry season (p < 0.05) (2.52 A +/- 0.50 kg/day for A1/2SA1/2AN and 2.41 A +/- 0.38 kg/day for Saanen) than the rainy season (2.17 A +/- 0.27 kg/day for A1/2SA1/2AN and 2.28 A +/- 0.53 kg/day for Saanen). The MP correlations were very significant (p < 0.05), however low and negative, where it was higher when correlated with RR in Saanen goats. Under the conditions of the present study, it is concluded that the goats were influenced by climatic factors, where the rainy period was more likely to cause thermal stress in the animals.

A comparative study of production performance and animal health practices in organic and conventional dairy systems

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

The development of genomics applied to dairy breeding

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

The physiology and impact on fertility of the period of proestrus in lactating dairy cows

In cattle, proestrus begins with the initiation of luteolysis and ends with initiation of estrus and the GnRH/LH surge. This period is marked by a dramatic decrease in circulating progesterone (P4) that reaches a nadir by about 36-48 h in cows undergoing natural or prostaglandin F2 alpha (PGF)-induced luteolysis. Inadequate luteolysis is a cause of reduced fertility particularly in timed AI programs with small elevations in circulating P4 reducing fertility. Increasing circulating estradiol (E2) during proestrus is dependent on presence, size, and function of the dominant follicle and this varies during natural proestrus, due to whether animals have two or three follicular waves, and during PGF-induced proestrus, according to stage of the follicular wave at time of PGF treatment. Inadequate circulating E2 can limit fertility and increase pregnancy loss in some specific circumstances such as in cows with low BCS and in cows during heat stress. Thus, studies to optimize the length of proestrus and the concentrations of E2 and P4 during proestrus could produce substantial improvements in fertility and reductions in pregnancy loss.

The role of proestrus on fertility and postovulatory uterine function in the cow

Modern protocols to synchronize ovulations for timed artificial insemination and timed embryo transfer that include manipulations in the proestrus period (i.e., between luteolysis and estrus) affect fertility in cattle. Specifically, stimulating pre-ovulatory follicle growth and exposure to estrogens after CL regression increase the proportion of cows pregnant and decrease late embryo mortality. Such effects may be due to both preovulatory actions of estrogens and post-ovulatory actions of progesterone, as concentrations of the later hormone may be changed in response to manipulations conducted during proestrus. In the first portion of this paper we describe strategies used recently to manipulate the proestrus period in protocols for synchronization of ovulation, and to present evidence of their effects on fertility. Manipulations of timing and prominence of sex steroids during the proestrus and early diestrus that affect fertility may act on targets such as the endometrium. This tissue expresses receptors for both estrogens and progesterone and these hormones change endometrial function to support conceptus growth and pregnancy maintenance. However, specific cellular and molecular mechanisms through which fertility is affected via manipulations of the proestrus are poorly understood. In the second portion of this paper we describe a well-defined animal model to study changes in endometrial function induced by manipulations conducted during the proestrus. Such manipulations induced endometrial changes on sex steroid receptors expression, cell proliferation, oxidative metabolism and eicosanoid synthesis in the uterus, but not on glucose transport to uterine lumen. In summary, evidence is accumulating to support a positive role of increasing duration and estrogen availability during the proestrus on fertility to synchronization protocols. Such positive effects may be through changes in endometrial function to stimulate conceptus growth and survival.

Etiopatogenia e tratamento do deslocamento de abomaso em bovinos leiteiros de alta produção

The dairy business is in constant development, in order to achieve better results and higher profits to the producer, and this search for improvement has led to the selection of a herd more productive. But this has caused some problems heightened, among them the displacement of the abomasum, a disease that affects much of the high producing dairy herd. The main reasons are apparently related to the feeding management, with the abrupt changes that the animal suffers in the post partum period, with diseases that would cause abomasal atony favoring its displacement, among others. When affected, the animals lose their appetite and in milk production, and may even, in severe cases, death to come. Treatments described in literature are varied and there are conservative and chirurgical methods. The choice of a particular technique depends on the financial condition of the producer, the economic value of the cow and from personal experience and technique of the veterinarian. Understanding the clinical implications of displaced abomasum is necessary not only for its animal identification in the field and its appropriate treatment but also for finding the errors and inadequacies in the management system of production that trigger this disease

Estresse término na reprodução de vacas leiteiras

Climate change in tropical countries, like Brazil, causes major problems in dairy production due to an increase of heat stress effects. In recent years, milk production in Brazil increased 36.07%. The Southeast region remains a leader in production with herds of high producing Holstein cattle (mostly), which is more susceptible to heat stress. Thermal stress decreases fertility in direct and indirect ways. Conception rates are reduced of 40-60% during cooler months of the year and 10-20% in the warmer months. Negative effects of heat stress involve changes in reproductive hormones, follicular development, oocytes, and embryos, and decreased dry matter intake. Several studies discuss change in reproductive hormones, such as reduction in plasma concentration of GnRH, LH, and oestradiol, which lead to decreased detection of estrus and ovulation. Various methods are being studied to bypass these negative effects and increase the fertility of dairy cows under heat stress. Cooling systems are the most advantageous and can be associated with technologies such as ET and TAI

Study of the removal of chemical oxygen demand of the cheese whey and wastewater from dairy industry using Spirulina platensis

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

Prevalência dos principais vírus respiratórios em bovinos da raça holandesa, no estado do Paraná

Pós-graduação em Medicina Veterinária - FMVZ

Isolamento, cultivo, caracterização e criopreservação de células tronco mesenquimais derivadas de membrana amniótica, geléia de Wharton e sangue do cordão umbilical de fetos bovinos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Fontes de ácidos graxos insaturados na alimentação de vacas leiteiras no período seco

Pós-graduação em Zootecnia - FCAV

Strategic planning for dairy cattle: SWOT analysis applied to a property of a farmers' association in Dracena, São Paulo state, Brazil

The sector of milk production in Brazil is very heterogeneous (high-tech in large scale X family properties). This study aimed to develop a diagnostic as a basis for a strategic plan to face the challenges inherent in operating a dairy farm in property of a farmers' association in Dracena, São Paulo, Brazil. It was observed that the association needs a more efficient guidance in the marketing, production and finance areas, not to compromise the search for new markets and continued growth in activity.