Marco Antônio de Oliveira Viu

Effects of biostimulation and nutritional supplementation on pubertal age and pregnancy rates of Nelore heifers (Bos indicus) in a tropical environment

To determine effects of biostimulation (BIO) and dietary supplementation (BIO+S) on pubertal age and pregnancy rates, Nelore heifers (n=392) were randomly assigned to one of four treatment groups (n=98/group). All animals were in tropical environmental conditions, in the middle-west region of Brazil, grazing in pastures of Brachiaria brizantha, cv. Marandu; Panicum Maximum, cv. Tanzânia and Brachiaria humidícula. The heifers of the BIO group were kept in the presence of bulls while being maintained on pasture; the animals in the BIO+S group were kept in the presence of bulls while being managed on pasture and were fed a diet with greater energy and protein content to produce 0.49 kg of BW gain/day; the animals in control group (the NBIO) were kept away from bulls and under pasture conditions; and the animals in the NBIO+S group were kept away from bulls, were maintained on pasture, and were fed the same diet as the BIO+S group. Heifers were bred at 22-23 months of age, and pregnancy diagnosis was made 45 days after the end of the breeding season. There were differences (P<0.05) between groups regarding pubertal heifers up to 19 months (NPH), final body weight (FBW) and pregnancy rates (P<0.01), with an advantage for the animals in the BIO and BIO+S groups. Although the effect of a diet with greater protein and energy content was not clear in this experiment, the exposure of heifers to a male during the prepubertal period decreased age at the first breeding season, resulting in a significant reduction in age of first pregnancy in Nelore heifers kept under extensive management systems in a tropical environment.

Granular Vulvovaginitis Syndrome in Nelore pubertal and post pubertal replacement heifers under tropical conditions: role of Mycoplasma spp., Ureaplasma diversum and BHV-1.

In order to determine the role of Mycoplasma spp, Ureaplasma diversum and BHV-1 as causal agents of Granular Vulvovaginitis Syndrome in Nelore heifers raised under tropical conditions and based on the hypothesis that stressful conditions during puberty or breeding season would be a determinant factor for the infection, 340 heifers not vaccinated against BHV-1 were divided in Post-pubertal, in the beginning of the first breeding season, and Pubertal heifers. The vaginal lesion score (VLS) Grade 1 to 4 was giving according to lesion area and severity. Vaginal mucus was used to isolate Mycoplasma spp., Ureaplasma diversum and BHV-1. The predominant VLS was 2. No sample was positive for BHV-1; 48% were positive for Mycoplasma spp., Ureaplasma diversum, or both, with predominance of Ureaplasma diversum. Serum neutralization for BHV-1 showed more positive animals in pubertal group (23%); 3 of the paired sera demonstrated seroconversion. These data indicated that post-pubertal and pubertal Nelore heifers raised under extensive conditions are more susceptible to Mycoplasma spp. and Ureaplasma diversum. The hypothesis that the stress of pubertal period could lead to an acute vaginal infection by HBV-1 was not proofed.

The effect of offering an energy and protein supplement to grazing canchim beef cows either postpartum or both pre- and postpartum on lipid blood metabolites and folliculogenesis.

This study was designed to evaluate the effect of nutritional supplementation offered during the pre- and postpartum periods on serum cholesterol, triglycerides and total lipids of Canchim beef cows and their relationship with folliculogenesis. Thirty cows with predicted calving date between September and October, kept in pastures of Brachiaria brizantha cv. Marandú together with their calves, were randomly distributed into three experimental groups: the first received only a mineral mixture (Control Group, CG); the second group received a concentrate with 16%crude protein/kg dry matter (DM) and 3000 kcal digestible energy/kg DM offered for 45 days prepartum and 120 days postpartum (PREG); the third group received the concentrate from parturition until the 120th day postpartum (POSG). Consumption was estimated at 1% of body weight, and each cow received approximately 4.0 kg/day (fresh weight) of supplement. Blood samples were taken and an ultrasound examination of the ovaries was performed twice a week until the 60th day postpartum. The body condition score (BCS) and the weight of the cows were recorded at 15-day intervals from calving until the 60th day postpartum. Data are presented as mean+/-SEM. Mean weight and BCS at calving were, respectively, 448+/-54.9 kg and 6.2+/-0.25 (PREG); 432+/-71.1 kg and 5.5+/-0.69 (POSG); and 434+/-66.4 kg and 5.5+/-0.69 (CG). Total cholesterol (TC), triglycerides (TRIG) and total lipids (TLIP) were measured using colorimetry until the 60th day postpartum. TC averages were PREG 186+/-62.6 mg/dL, POSG 159+/-43.1mg/dL and CG 133+/-35.1mg/dL (P<0.05). For TRIG, the means were PREG 29+/-11.3mg/dL (P<0.05), POSG 24+/-8.1mg/dL and CG 26+/-12.1mg/dL (P>0.05). Serum concentrations of TLIP were PREG 588+/-145.6 mg/dL, POSG 512+/-137.6 mg/dL and CG 452+/-122.4 mg/dL (P<0.05). The first dominant follicle (DF) was identified on Day 21+/-10.3 (PREG), 36+/-28.5 (POSG) and 51+/-32.8 (CG) after calving. The difference between PREG and CG was significant (P<0.05). TC was positively correlated with the calving to first estrus interval (P<0.05). Results showed that nutritional supplementation before parturition assured good body condition at calving and suggested that it was effective at increasing cholesterol availability to maintain ovarian follicle function and to favor earlier resumption of ovarian activity.

Ovarian activity and oocyte quality associated with the biochemical profile of serum and follicular fluid from Girolando dairy cows postpartum

This study was designed to evaluate the influence of heat stress (HS) on the metabolic profile of serum and follicular fluid (FF), ovarian follicle development, and oocyte quality of Girolando dairy cows. Oocytes, blood, and FF (follicles ≥9mm) samples were obtained at 30, 45, 60, 75, and 90 days postpartum in the summer and winter seasons. During transvaginal follicular aspiration, rectal temperature (RT), body condition score (BCS), number of ovarian follicles, and quality of oocytes were recorded. The ambient air temperature (AT) and relative humidity (RH) were also recorded to calculate the temperature humidity index (THI). Glucose, total cholesterol (TC), triglycerides (TG), urea, sodium (Na), potassium (K), and calcium (Ca) concentrations were determined using serum and FF samples. The RT, THI, and BCS loss were greater (P<0.01) in the summer; however, glucose, Na, and K serum concentrations decreased in the same season (P<0.05). Degenerated oocytes were positively associated (P<0.05) with THI (r=0.14) and AT (r=0.13), and negatively associated with glucose (r=-0.12) and K (r=-0.11) serum concentrations. HS induces metabolic changes, which compromise the number of ovarian follicles and the follicular environment, thus resulting in morphologically damaged oocytes.

Metabolic profile of serum and follicular fluid from postpartum dairy cows during summer and winter.

This study was designed to monitor the biochemical profiles of serum and follicular fluid (FF) of postpartum dairy cows during the summer (n=30) and winter (n=30). Blood and FF (follicles ≥ 9 mm) were obtained from Girolando cows at 30, 45, 60, 75 and 90 days postpartum. The samples were collected and analysed to determine glucose, total cholesterol (TC), triglyceride (TG), urea, sodium (Na), potassium (K) and calcium (Ca) levels. Throughout the study, the following clinical variables were measured: rectal temperature (RT), respiratory rate (RR) and body condition score (BCS). In addition, the temperature humidity index (THI) was calculated for each season. During the summer season, THI was higher, BCS decreased, there was an increase in RT, and glucose, urea, Na and K serum levels were decreased (P<0.05). The levels of TC, TG, urea, K and Ca in follicular fluid increased (P<0.05). Positive correlations (P<0.05) were observed between the serum and FF levels for glucose (r=0.29), TC (r=0.24) and Ca (r=0.30). Therefore, the biochemical profile of serum and FF of dairy cows under summer heat-stress conditions demonstrates marked changes that may impair fertility during lactation.

Administração de acetato de melengestrol após inseminação artificial em tempo fixo em vacas Nelore lactantes

The objective of the present study was to assess the effect of administration of Melengestrol Acetate (MGA® Premix) after FTAI, on the conception rate in lactating Nelore breed cows. Experiment I, assessed the effect of administration of 2.28 g MGA/cow/day, from day 13 (D13) until day 18 (D18) after FTAI. The cow were divided into two groups, Group I (n=83, control) that cows were submitted just to FTAI and Group II (n=104, treated) that cows received MGA after FTAI. Experiment II, assessed the effect of administration of 2.28g MGA/cow/day, from day 5 (D5) until day 10 (D10) after FTAI. The cow were divided into two groups, Group I (n=94, control) that cows were submitted just to FTAI and Group II (n=100, treated) that cows received MGA after FTAI. Gestation was diagnosed in both experiments 45 days after FTAI. The conception rates were analyzed by Qui-Square test. In experiment I, The conception rates were 42,16% for control group and 50,0% for treated group (p>0,05). In Experiment II, the conception rate of control group (47,87%) was higher than treated group (28,0%). It was conclude that administration of MGA®Premix from D13 until D18 after FTAI didn’t affect the conception rate. However, when administered from D5 until D10, reduced the conception rate in lactating Nelore breed cows.

Suplementação de bezerros lactentes em cocho privativo: Revisão

The beef market in Brazil has undergone great changes which directly affect the rural producer. Consumer markets have required products with best quality. Thereat, the systems of creation are evolving to allow the animals being slaughtered younger and with higher weights. The rural properties have wanted fit on this new reality, being that properties as perform calf creates phase they begin to have great importance on the supply chain meat. These need to adopt new techniques that allow the weaning of calves heaviest and greater uniformity on the batch, facilitating the working next phase, the rebuilds. The use of a differentiated and private diet there for the calves on the lactating phase it’s an alternative to achieve the production goal of superior animals at weaning.

Nutrição clínica de cães hospitalizados: Revisão

Several studies show that nutrition of hospitalized dogs is important for patient recovery. However this aspect is often neglected in veterinary medicine. Thus, this work was developed with the purpose of clarifying the importance of the adequate nutritional support implementation for hospitalized dogs and its relation with the most commonly found in the clinical routine.

Diarreia viral bovina: revisão

The bovine viral diarrhea (BVD) is a disease of major negative economic impact, endemic in most countries and causing productive and reproductive VIU, M.A.O. et al. Diarreia viral bovina: revisão. PUBVET, Londrina, V. 8, N. 3, Ed. 252, Art. 1670, Fevereiro, 2014. losses. In Brazil, the disease is widespread in cattle herds. The infection occurs in most bi-ungulates, but the prevalence is in cattle. This review aims to point out relevant features of the BVD, covering its etiology, epidemiology, pathogenesis, symptoms, diagnosis, prognosis, treatment and control.

Associações entre características andrológicas e de carcaça em touros Nelore

The aim with this study was to verify the existence of genetic associations among carcass traits, and andrology traits in Nellore young bulls. Breeding soundness and carcass examinations were done on 223 Nellore males with average of 21 months age. To estimate the genetic parameters the bayesian inference was used through the software THRGIBBS1F90. The heritability estimates was obtained for DEFMAI, DEFMEN, DEFTOT, AR, AOL, EG and P8 were 0.33, 0.20, 0.21, 0.35, 0.32, 0.28, and 0.29, respectively. The genetic correlation estimates of DEFTOT with AOL, EG and P8 were –0.46, –0.28, and –0.19, respectively; to AR with these same characteristics were –0.60, –0.03, and –0.12, respectively. The results of this study demonstrate that there is a favorable correlated response between repro-ductive and carcass traits studied.