Species-specific nested PCR as a diagnostic tool for Brucella ovis infection in rams

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

Comparison of agar gel immunodiffusion test, rapid slide agglutination test, microbiological culture and PCR for the diagnosis of canine brucellosis

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Influence of sire and sire breed (Gyr versus Holstein) on establishment of pregnancy and embryonic loss in lactating Holstein cows during summer heat stress

Heat stress has negative effects on pregnancy rates of lactating dairy cattle. There are genetic differences in tolerance to heat stress; Bos taurus indicus (B. t. indicus) cattle and embryos are more thermotolerant than Bos taurus taurus (B. t. taurus). In the present study, the effects of sire and sire breed on conception and embryonic/fetal loss rates of lactating Holstein cows during the Brazilian summer were determined. In Experiment 1, cows (n = 302) were AI after estrus detection or at a fixed-time with semen from one Gyr (B. t. indicus) or one Holstein sire (B. t. taurus). Pregnancy was diagnosed 80 days after AI. In Experiment 2, cows (n = 811) were AI with semen from three Gyr and two Holstein sires. Pregnancy was diagnosed at 30-40 and at 60-80 days after AI. Cows diagnosed pregnant at the first examination but non-pregnant at the second were considered as having lost their embryo or fetus. Data were analyzed by logistic regression. The model considered the effect of sire within breed, sire breed, days postpartum, period of lactation, and AI type (AI after estrus versus fixed-time). There was no effect of the AI type, days postpartum or milk production on conception or embryonic loss rates. The use of Gyr bulls increased pregnancy rate when compared to Holstein bulls [9.1% (60/657) versus 5.0% (23/456), respectively, P = 0.008; data from Experiments 1 and 2 combined]. Additionally, in Experiment 2, cows inseminated using semen from sire #4 (Gyr) had lower embryonic loss (10%) when compared with other B. t. indicus (35.3% and 40%) or B. t. taurus sires (18.2% and 38.5%, P = 0.03). In conclusion, the use of B. t. indicus sires may result in higher conception rates in lactating Holstein cows during summer heat stress. Moreover, sire can affect embryonic loss and selection of bulls according to this criterion may result in higher parturition rates in lactating Holstein cows. (c) 2006 Elsevier B.V. All rights reserved.

Selection of X chromosome of buffaloes sperm with Percoll gradients

The aim of the present study was to evaluate the selection of X chromosome of buffaloes sperm with Percoll gradients. The stock solution of Percoll was prepared in the proportion of 1:11 (1 part of Percoll:11 parts of a solution containing KCl 1M, NaH(2)PO(4) 0.1M, NaCl 1.5M and sodium HEPES 23.8 g/ml). In order to prepare 9 different gradients were added to the stocked Percoll the A solution (glicine-yolk extender) in the following proportions: 90, 80, 72, 65, 57, 49, 34 and 25%. A sample of 0.7 ml of the fresh semen was deposited at 2 ml of Percoll 80% for the sperm wash. The precipitate was put in tube with 0.7 ml of each gradient. Then, the precipitated was washed in TES solution by centrifugation (500xg for 10 minutes), and collected again and diluted in TES solution to be freeze. The presence of the F body in the spermatozoa was observed in 58.7 +/- 5.4% of the control group and in 41.2 +/- 5.4% of the treated group (p<0.01). This result showed an increment of 17.55 of male sperm in the Percoll's group. The reduction of the centrifugation force did not improve the percentage of X sperm.

Comportamento sexual de touros Zebuínos e Angus em central de coleta e processamento de sêmen

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Parâmetros e tendência genética da produção de leite de cabra no Brasil

A caprinocultura leiteira no Brasil, apesar de ser uma atividade rural consolidada há algumas décadas, tem se mostrado totalmente dependente de outros países no que se refere ao melhoramento genético. A maioria dos plantéis existentes atualmente tem como base animais importados, e a renovação do material genético é feita por meio da importação de sêmen. Inexistem informações sobre o valor genético dos animais e sua evolução no decorrer dos anos. No presente trabalho, foram estimadas a herdabilidade e a repetibilidade da produção de leite utilizando o REML. Os valores obtidos foram 0,21557 e 0,21564, respectivamente. Para a predição do valor gênico dos animais, foi usado o procedimento BLUP com modelo animal. A mudança na tendência genética anual estimada por um modelo quadrático foi -0,8109 kg/ano², indicando desaceleração no ganho genético. A correlação de Pearson entre os valores gênicos dos bodes estimados com base na média da capacidade provável de produção das filhas obtida pelo método de mínimos quadrados com as estimadas pelas equações do modelo misto foi de 0,5751. A correlação de SPEARMAN entre as classificações dos bodes obtidos pelos dois métodos foi de 0,5813.

Ocorrência de lesões em carcaças de bovinos de corte no Pantanal em função do transporte

O trabalho teve como objetivo avaliar a influência do transporte na ocorrência de lesões, em carcaças de bovinos abatidos no Pantanal Sul Matogrossense, por meio da quantificação do número e do tamanho das lesões, assim como a localização da freqüência de ocorrência das lesões nos principais cortes comerciais padronizados para o mercado interno. do total de 121 carcaças avaliadas, foi observado que 102 (84,3%) tiveram uma ou mais lesões, totalizando 270 lesões que resultaram na remoção de 56,1kg de carne, com média geral de 0,5kg por animal ou 0,6kg por animal, considerando-se apenas os animais que tiveram lesões. A freqüência de lesões em carcaças de bovinos evidenciou diferença significativa de acordo com as condições de transporte. As maiores proporções de lesões foram encontradas em animais submetidos ao transporte rodoviário por mais de uma hora e distâncias maiores que 70km, sendo grande parte em estradas não-pavimentadas. Conclui-se que os animais submetidos à série sucessiva de manejo e transportados em estradas não-pavimentadas por longas distâncias apresentaram maior proporção de lesões, sendo que os animais provenientes do lote VI apresentaram maior número de lesões.

Morphological asymmetry and broiler welfare

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

Effects of twenty-four hour transport or twenty-four hour feed and water deprivation on physiologic and performance responses of feeder cattle

The objective of this study was to compare the effects of 24-h road transport or 24-h feed and water deprivation on acute-phase and performance responses of feeder cattle. Angus x Hereford steers (n = 30) and heifers (n = 15) were ranked by gender and BW (217 +/- 3 kg initial BW; 185 +/- 2 d initial age) and randomly assigned to 15 pens on d -12 of the experiment (3 animals/pen; 2 steers and 1 heifer). Cattle were fed alfalfa-grass hay ad libitum and 2.3 kg/animal daily (DM basis) of a corn-based concentrate throughout the experiment (d -12 to 28). on d 0, pens were randomly assigned to 1 of 3 treatments: 1) transport for 24 h in a livestock trailer for 1,200 km (TRANS), 2) no transport but feed and water deprivation for 24 h (REST), or 3) no transport and full access to feed and water (CON). Treatments were concurrently applied from d 0 to d 1. Total DMI was evaluated daily from d -12 to d 28. Full BW was recorded before treatment application (d -1 and 0) and at the end of experiment (d 28 and 29). Blood samples were collected on d 0, 1, 4, 7, 10, 14, 21, and 28. Mean ADG was greater (P < 0.01) in CON vs. TRANS and REST cattle but similar (P = 0.46) between TRANS and REST cattle (1.27, 0.91, and 0.97 kg/d, respectively; SEM = 0.05). No treatment effects were detected for DMI (P >= 0.25), but CON had greater G: F vs. TRANS (P < 0.01) and REST cattle (P = 0.08) whereas G: F was similar (P = 0.21) between TRANS and REST cattle. Plasma cortisol concentrations were greater (P <= 0.05) in REST vs. CON and TRANS cattle on d 1, 7, 14, and 28 and also greater (P = 0.02) in TRANS vs. CON cattle on d 1. Serum NEFA concentrations were greater (P < 0.01) in REST and TRANS vs. CON cattle on d 1 and greater (P < 0.01) in REST vs. TRANS cattle on d 1. Plasma ceruloplasmin concentrations were greater (P = 0.04) in TRANS vs. CON cattle on d 1, greater (P = 0.05) in REST vs. CON on d 4, and greater (P <= 0.05) in REST vs. TRANS and CON on d 14. Plasma haptoglobin concentrations were greater (P < 0.01) in TRANS vs. CON and REST cattle on d 1 and greater (P <= 0.05) for REST vs. TRANS and CON cattle on d 7. In conclusion, 24-h transport and 24-h nutrient deprivation elicited acute-phase protein reactions and similarly reduced feedlot receiving performance of feeder cattle. These results suggest that feed and water deprivation are major contributors to the acute-phase response and reduced feedlot receiving performance detected in feeder cattle transported for long distances.

Fertility-associated antigen on Nelore bull sperm and reproductive outcomes following first-service fixed-time AT of Nelore cows and heifers

The objective was to determine whether the presence of fertility-associated antigen (FAA) on sperm collected from Nelore (Bos indicus) bulls can be used to assess potential fertility of sperm for use at first-service fixed-time AI (TAI). Six Nelore bulls were selected based on FAA status (FAA-negative: N = 3; FAA-positive: N = 3) and the ability to produce neat semen with >= 70% morphologically normal sperm and 60% estimated progressive motility before cryopmservation. In Experiment 1, suckled multiparous Nelore cows (N = 835) were evaluated for body condition score (BCS) and received an intravaginal progesterone device (CIDR) and 2.0 mg of estradiol benzoate (Day 0). on Day 9 the CIDR was removed, 12.5 mg of PGF(2 alpha) and 0.5 mg of estradiol cypionate were administered, and calves were removed for 48 h. All cows received TAI on Day II (48 h after CIDR removal). Pregnancy per TAI (P/TAI) was not different between FAA-positive and FAA-negative bulls (41.5% vs. 39.3%, respectively). There was an effect of AI technician on P/TAI (36.0% vs. 43.9%; P < 0.05) and BCS tended to affect P/TAI (P = 0.09), as cows with BCS >= 2.75 were 1.4 times more likely to become pregnant compared with cows with BCS < 2.75. In Experiment 2, nulliparous Nelore heifers (N = 617) were evaluated for BCS and received a CIDR and estradiol benzoate (2.0 mg) on Day 0. on Day 7, all heifers received PGF(2 alpha) (12.5 mg). on Day 9, CIDR inserts were removed and all heifers received estradiol cypionate (0.6 mg) and 200 IU eCG. All heifers received TAI on Day 11 (48 h after CIDR removal). Pregnancy/TAI was different (P = 0.04) between FAA-positive and FAA-negative bulls (33.7% vs. 40.7%, respectively). Presence of FAA on sperm was unsuccessful in assessing the potential fertility of sperm for use in TAI. (C) 2012 Elsevier B.V. All rights reserved.

Effects of temperament and acclimation to handling on feedlot performance of Bos taurus feeder cattle originated from a rangeland-based cow-calf system

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Cryopreservation effects on domestic cat epididymal versus electroejaculated spermatozoa

Frozen-thawed epididymal spermatozoa have already been successfully used in artificial insemination in the domestic cat, proving to be a valuable resource for the reproduction of felid species, which are threatened with extinction. The aim of this study was to compare the effects of freezing and thawing on domestic cat semen collected by electroejaculation (EL) and from the epididymides (EP) and vasa deferentia. Ten adult cats were anesthetized, electroejaculated and immediately thereafter, orchiectomized. Epididymal spermatozoa were collected through the compression of caudae epididymidis and vasa deferentia. Spermatozoa were frozen-thawed following a single protocol. Sperm motility, sperm progressive status (0-5), plasma membrane integrity and morphology (light and transmission electron microscope) were assessed on two occasions, immediately after collection and after freezing and thawing. There were no significant differences between the electroejaculated and epididymal fresh or frozen-thawed spermatozoa for any of the variables. However, the incidence of acrosome defects after freezing and thawing increased by 19% based on light microscopy, whereas ultrastructural images revealed acrosome damages in most sperm cells. Since these acrosomal changes are known to affect sperm fertilising capacity, further studies are needed to optimize cryopreservation techniques for epididymal as well as electroejaculated domestic cat spermatozoa. (c) 2006 Elsevier B.V. All rights reserved.

Acrosomal ultrastructure of stallion spermatozoa cryopreserved with ethylene glycol using two packaging systems

The present experiments aimed to examine the substitution of glycerol (G) by ethylene glycol (E) as a cryoprotective agent for stallion spermatozoa. Two different ethylene glycol concentrations (5% and 10%) and also the association of glycerol (2%) and ethylene glycol (3%) (E/G) were studied (Experiment 1). In Experiment 2, two packing systems (0.5 x 4.0 ml) were evaluated using both cryoprotectors. In both experiments, the sperm membrane integrity after freezing was evaluated using transmission electron microscopy. The mean post-thaw motility was 34.25, 36.5, 29.25 and 34.75% for G5%, E5%, E10% and E/G, respectively. It was observed that the percentage of motile spermatozoa was significantly smaller (P<0.05) when semen was processed with E10%. A decrease in the acrosome integrity was observed in frozen thawed spermatozoa from all treated groups. It was observed that 28.0, 22.5, 25.5 and 22.5 % of the sperm cells had a normal acrosome following freezing with G5%, E5%, E10% and E/G, respectively. Undulation of the outer acrosomal membrane, acrosomal swelling and loss of acrosomal content density and homogeneity were the most evident ultrastructural alterations observed. In Experiment 2, the post-thaw motility was higher (P<0.05) for sperm frozen in 0.5 ml straws than in 4.0 mi straws, regardless of the cryoprotector used. The ultrastructural evaluation showed 26.7 and 16.0% of intact acrosomes for sperm frozen in 0.5 ml and 4.0 ml straws, respectively. We concluded that ethylene glycol has similar cryoprotective properties to glycerol and that utilisation of 0.5 ml straws improved the ability of horse sperm cells to withstand damage after the cryopreservation process.

Ovarian morphometric characterization and in vitro maturation of oocytes obtained from buffalo (Bubalus bubalis) ovaries - partial results

Buffalo ovaries were collected from a slaughterhouse (Frigol, Brazil) and transported to the laboratory in saline solution at 36 degrees C. The ovaries were dissected to realize the evaluations (weight, length, width and height of the ovary; corpus luteum and dominant follicle diameters). The Cumulus-oocyte complexes (COCs) were recovered by aspiration of 2-8 mm follicles. Selected COCs were matured in TCM 199 supplemented with 10% fetal bovine serum, sodium pyruvate, LH, FSH, estradiol and gentamicin. In vitro maturation was carried out at 38.5 degrees C for 22-24 h and 34-36 h. For the evaluation of the nuclear maturation the oocytes were placed in TCM 199 medium added with type v hialuronidase where the granulosa cells were extracted. The denuded oocytes were transferred to 10 mu l of Hoescht 33342 and the chromosomic configuration was evaluated. The oocytes were classified according to meiosis stage in: Germinal Vesicle, Germinal Vesicle Breakdown, Metaphase I, Metaphase II and Degenerated. The means of weight, length, width and height of the ovary were 3.83 g, 2.27 cm, 1.08 cm and 1.56 cm, respectively. The means of corpus luteum and dominant follicle diameters were 1.40 cm and 7.77 mm. The proportion of oocytes that reached metaphase II stage was: 36.68%.