Viabilidade do parasitismo por Haemonchus contortus em bovinos experimentalmente infectados

Pós-graduação em Zootecnia - FCAV

Human-calf relationship and its implications on animal welfare

Pós-graduação em Zootecnia - FCAV

Cuidados essenciais ao bezerro neonato nas primeiras 24 horas de vida

The change from the uterine environment to the external environment that occurs afterbirth requires rapid adaptation of the newborn. The right care in the first 24 hours of life can significantly reduce calves’ mortality. In this context, are included essential care to animals that are born weak and require immediate assistance so they can adapt to the extra uterine environment, such as stimulating the onset of spontaneous breathing and thermoregulation. The essential care is also related to colostrum feeding and treatment of the navel. The objective of this work is to bring together some of the major causes of morbidity and mortality in the first 24 hours of life of the newborn calf and discuss some of the special care that these animals require

Puberdade em novilhas

The age which heifers reach puberty depend on factors like genetics, environment and nutrition. Puberty in heifers can be defined as the onset of reproductive competence, the ability to ovulate a fertile oocyte with an estrous behavior and development of a corpus luteum with normal lifespan. The metabolic signals that trigger puberty are not yet fully defined. In Brazil, where most beef cattle are zebu, the age at puberty is very advanced, mainly these animals are feed with a poor diet. Many researches are trying to discover the metabolic signals that trigger puberty and anticipate better economic return in breeding farms. It has been demonstrated that the cascade of endocrine events that culminate in puberty can be hastened by an alternative management scheme that involves increased nutrient intake between 3 and 7 months of life. Different diet concentrations, different products and by-products have been used in research to achieve puberty early (less than 300 days of age). The hormonal induction of puberty, especially with the use of progestagens, has been developed in heifers as an alternative tool to improve reproductive efficiency in herds, increasing the amount of pregnant heifers in breeding season

Anormalidades fetais e placentárias decorrentes da produção in vitro de embriões bovinos

In vitro production of bovine embryo (IVP) has become a remarkable assisted reproduction biotechnology in Brazil, once it is considered an important tool for the genetic improvement of the herd. However, many abnormalities are associated with IVP technologies, such as higher incidences of embryo loss, abortions, hydrallantois and dystocia, prolonged gestation, increased birth weight and high perinatal mortality. Collectively, these abnormalities are known as “Large Offspring Syndrome”, which has limited the large-scale use of IVP technologies in cattle industry

Anestro pós-parto: luteólise prematura

The prolonged postpartum anoestrus in cows reduces the number of calves leading to a significant economic loss to producers. Suckling and nutrition are the factors of great importance to the extension of the post-partum period. Besides, the occurrence of short cycles within 30 to 40 days postpartum contributes to an increase in the parturition–conception interval. These cycles are related to development of a corpus luteum with reduced duration after the first ovulation (less than 12 days). It is known that the short persistence of the corpus luteum is caused by advance of the luteolytic mechanisms. However, there is a lack of consensus regarding the cause of this anticipation. There are two currently accepted hypotheses, one related to the lack of prior exposure to progesterone, and the other related to the low concentration of pre-ovulatory estrogen. Considering the decrease in the incidence of short cycles in cows treated with progesterone and estrogen, the main protocols of ovulation induction include combination of both hormones. Therefore, this study aimed at describing the post-partum anestrous in cows and the main predisposing factors, emphasizing the first postpartum ovulation, short cycle and, its respective causes and consequences

Utilização de gonadotropina coriônica equina em protocolos de inseminação artificial em tempo fixo em bovinos de corte

Current cattlemen must seek methods to maximum reproductive efficiency of their beef herds, making the business competitive and enhancing greater profitability. For the cow-calf producers, efficiency translates into more cows producing one calf every year. Fixed-time artificial insemination (TAI) is one of several technologies that producers utilize to reach this goal. Postpartum anestrus is one of the biggest obstacles to overcome in order to obtain suitable results at the end of the breeding season. The TAI protocols are efficient in re-establishing cyclicity in noncycling cows during the postpartum period, streamlining the use of labor on farms, allowing the use of artificial insemination (AI) on a large scale, and introducing superior genetics to the herd. The protocols that are most commonly used in Brazil are based on progesterone (P4) releasing devices that prevent premature estrus and ovulation; and estradiol (E2) to synchronize the initiation of a new follicular wave. In such protocols, administration of equine chorionic gonadotropin (eCG) helps the development of the follicle, increases ovulation rate, improves the endocrine and uterine environment during proestrus and diestrus, and improves fertility. The use of eCG in TAI protocols for suckled cows, non-lactating cows and heifers increases the pregnancy rate allowing more calves at the end of the breeding season and higher profitability to the cattlemen

Pneumonias em Bovinos Neonatos

Pneumonia is a respiratory disease that most affects the cattle, especially calves, which according to their anatomical and physiological characteristics are more susceptible to respiratory diseases compared to other large mammals. Therefore, prevention of pneumonia is a key factor to minimize the possible economic losses generated by the early involvement of a calf by these diseases, which can cause a decrease in animal development. Despite the multifactorial etiology and classification on the types of pneumonia is still subject of discussion, most pneumonias are in three categories: bronchopneumonia, interstitial pneumonia and metastatic pneumonia, the first being the most important among them. Clinical signs vary with the cause, but are classified as medical conditions ranging since subclinical to clinically irreversible. Treatment depends on the clinical experience and can associate drugs for alleviating the symptoms with anti-inflammatories and antibiotics. Thus, premature diagnosis is directly linked to prognosis, treatment costs and spread of the disease

Fatores que podem influenciar o sexo da cria em bovinos

To assess the possibility of shifting the sex ratio at birth, since this can contribute to enhancing the genetic gain and producity in cattle, this work is aimed at raising the factors that may influence sex determination of creates. This study is based on research conducted in the area of reproduction and production of beef and dairy cattle, some quotes in humans, mouse, dogs and a study in pigs. This was due to back of data and studies in the bovine species. It was noted that stress during pregnancy, intake of vitamin C or others substances and the time of artificial insemination are the factors that may influence the determination of the type of product. Human studies, concluded that woman more stressed are more likely to produce female children of the quietest. Furthermore, sows that received ascorbic a ad orally for seven days and were inseminated during this period, produce more female then those who did not receive the vitamin. These studies may suggest that cows can also suffer influence of stress and food for the determination of sex of calf. There are also studies suggesting that cows inseminated at the earliest time of ovulation ted to produce more male calves than those inseminated a few hours before that time. Some scholars considers the hypothesis... (Complete abstract click electronic access below)

Indução de parto em bovinos: Princípios e aplicações

Currently, Brazil has one of the largest cattle herds worldwide. In order to keep that milk and meat were introduced reproductive biotechnologies such as artificial insemination, embryo transfer and in vitro fertilization. In certain situations the technique may have undesired effect, for example, the production of calve calves due to the very large increase in the gestation period when performed in vitro fertilization. To avoid this problem we perform the induction of labor in order to prevent the product is longer the womb. This induction can also be made in case of diseases that compromise the life of the mother, twin pregnancy an abnormal size calf. The administration of short acting steroids, prostaglandins, association of short acting steroids and prostaglandins and association of short acting steroids, prostaglandins and long-acting corticosteroids are some of the possibilities of induction

Práticas sanitárias e percepção de risco de produtores de bovinos de corte no Pantanal de Mato Grosso do Sul

Pós-graduação em Medicina Veterinária - FCAV

Epidemiologia molecular de rotavírus em rebanhos bovinos no estado de São Paulo no período de 2006 a 2010

Pós-graduação em Medicina Veterinária - FCAV

Utilização do meloxicam para reduzir respostas Inflamatórias em bovinos de corte transportados

Pós-graduação em Zootecnia - FMVZ

Cryptococcus: isolamento ambiental e caracterização bioquimica

Pós-graduação em Ciência Animal - FMVA

Comportamento individual de bovinos Nelore e relações com desempenho em regime de confinamento e reprodução

Pós-graduação em Zootecnia - FCAV