Background: Contamination of the uterine lumen with bacteria is ubiquitous in cattle after parturition. Some animals develop endometritis and have reduced fertility but others have no uterine disease and readily conceive. The present study tested the hypothesis that postpartum cattle that develop persistent endometritis and infertility are unable to limit the inflammatory response to uterine bacterial infection.
The objective of this study was to evaluate the mechanism of action through which conjugated linoleic acid (CLA) beneficially affects reproduction. Lactating Holstein cows (n = 45, 20 +/- 1 DIM) were assigned to 1 of 3 treatments: 70 g/d of Ca salts of tallow (control); 63 g/d of lipid-encapsulated CLA providing 7.1 g/d of cis-9, trans-11 CLA and 2.4 g/d of trans-10, cis-12 CLA (CLA 75:25); or 76 g/d of lipid-encapsulated CLA providing 7.1 g/d each of cis-9, trans-11 and trans-10, cis-12 CLA (CLA 50:50). Supplements were top-dressed for 37 d, milk production and DMI were recorded daily, and blood samples were taken 3 times per week. At 30 +/- 3 DIM, ovulation was synchronized in all cows with a modified Ovsynch protocol, and on d 15 of the cycle cows received an oxytocin injection; blood samples were obtained frequently to measure 13,14 dihydro, 15-keto PGF2alpha. On d 16 of the cycle cows received a PGF2alpha injection and ovarian follicular aspiration was performed 54 h later. Follicular fluid was analyzed for fatty acids, progesterone, and estradiol. Endometrial biopsies were taken before and again near the end of the supplementation period for fatty acid analysis. The CLA resulted in decreased milk fat content of 14.1 and 6.1% at wk 5 of treatment of CLA 50:50 and CLA 75:25, respectively. There were no differences in energy balance or plasma nonesterified fatty acids; however, plasma IGF-I was greater in cows supplemented with CLA 50:50. The CLA isomers were not detectable in endometrial tissue, but cis-9, trans-11 CLA tended to be greater in follicular fluid of supplemented cows. Response to the oxytocin challenge was not different among treatments. Progesterone during the early luteal phase and the estradiol:progesterone ratio in follicular fluid tended to be greater in cows supplemented with CLA 50:50. Overall, these results indicate that short periods of CLA supplementation do not alter uterine secretion of PGF2alpha. The mechanism through which CLA affects reproduction may involve improved ovarian follicular steroidogenesis and increased circulating concentrations of IGF-I.
Endometrial samples were obtained from 56 consecutively calving dairy cows examined for endometrial cytology and for aerobic and anaerobic bacterial growth. Changes over time, correlations between different cell types and between cell and bacterial populations and with fertility measures were calculated. The proportion of neutrophils in cytologic preparations decreased with time postpartum. Other cell types did not change significantly with time. The proportion of neutrophils early (Day 0 and 7) postpartum was negatively correlated with neutrophil proportion at 5 or 7 weeks postpartum and positively correlated with fertility. Cows with high proportion of neutrophils at 7 days postpartum (>40%) were significantly more likely to become pregnant than those with lower proportions of neutrophils. Escherichia coli were the bacteria most frequently isolated at 0 or 7 days postpartum but were uncommon after that. Trueperella pyogenes were most prevalent at 3 weeks postpartum and were more likely to infect cows that had previously been infected with E coli. The presence of T pyogenes at 3 weeks postpartum increased the risk of concomitant or later infection with gram-negative anaerobes. The presence of T pyogenes at 3 weeks postpartum significantly reduced the risk of pregnancy at 150 days in milk. The presence of alpha-hemolytic Streptoccus spp. at 7 days postpartum was associated with improved reproductive performance. The proportion of neutrophils at 5 and 7 weeks postpartum was related to concomitant bacterial infection. These findings suggest that rapid mobilization of neutrophils to the postpartum uterus is a beneficial response for uterine health in dairy cows.
RESUMO -A análise de um banco de dados de crescimento em ovinos Bergamácia (pesos até dois anos de idade de 1982 a 1996) foi feita usando-se métodos não-lineares para determinar parâmetros de três curvas (Brody, Richards e Logística) de crescimento. Os parâmetros das curvas foram analisados pelo Statistical Analysis System (SAS) usando o procedimento GLM e CORR para determinar fatores que influenciaram os parâmetros e as correlações entre os parâmetros e pesos dos animais. O sistema de manejo foi semi-extensivo com os ovinos ao pasto durante o dia e presos à noite para proteger dos predadores. Os fatores fixos incluídos foram ordem do parto, sexo do cordeiro, tipo de nascimento, mês e ano. As médias dos parâmetros das curvas foram: Richards -A = 50,024, B = 0,647, k = 0,003, M = 17,771 e R² = 0,838; 763, B=0,885, k =0,003, R²= 0,842;894,895, k=0,007 e R²= 0,840. O meio ambiente influenciou o crescimento e a reprodução de ovinos na região de Brasília. A correlação negativa entre k e A indica que animais que amadurecem mais cedo têm menos probabilidade de atingir pesos adultos mais altos que animais que amadurecem tardiamente. A curva Logística estimou o peso adulto dos animais com média inferior às das outras curvas. Os pesos atuais estão, contudo, mais bem correlacionados com os estimados pela Logística. Não houve diferença entre os três tipos de curvas em termos de R². O quadrado médio do resíduo foi maior para a curva de Richards. A curva recomendada para ajustar dados de crescimento de ovinos da raça Bergamácia é Logística.Palavras-chave: curvas de crescimento, ovinos, fatores ambientais Parameters for Three Growth Curves and Factors that Influence Them for Bergamasca Sheep in the Brasilia RegionABSTRACT -Fifteen years of data from a flock of Bergamasca sheep weighed every two weeks was analyzed using non-linear methods to determine parameters of three growth curves (Brody , Richards and Logistic). The curve parameters were analyzed using Statistical Analysis System (SAS) procedures GLM and CORR to determine factors which influenced them and correlations between the parameters and weights at determined ages. Fixed effects in the model included lambing number, sex of lamb, type of birth and month and age of lambing. The management system is semi-extensive, with the sheep at pasture during the day and imprisoned at night to protect them against predators. Means of the parameters were: Richards; A = 50.024, B = 0.647, k = 0.003, M = 17.771 and R²= 0.838; Brody; A= 52. 763, B=0.885, k=0.003, R²= 0.842; Logistic; A =47.894, k=0.007 and R²= 0.840. The environment influenced the growth of sheep in the region of Brasilia. The Logistic curve estimated adult weights lower than the other curves but the actual weights were better correlated with those estimated by this curve. There was no difference between the curves in terms of R², and the error mean square was higher for the Richards curve. The negative correlation between A and k indicates that early maturing animals were less likely to reach high mature weights,...
In France, as in many other western countries, dogs are an important part of the society as pets or working animals. The exact demand for puppies in France is unknown, as is the proportion of dogs coming from different breeding sources. Nevertheless, the origin of puppies is important since young dogs from puppy mills and pet stores appear to be more likely to develop behavioral disorders. Puppies coming from responsible breeders, on the other hand, tend to be better adapted. In well-managed kennels, an explanation for these behavioral differences may be associated with greater contact of litters with the dam and humans. Another factor that might influence a dog’s temperament and character is maternal behavior. Although recent studies have shown that the quality of maternal care in dogs is important, direct effects on the development of behavioral problems such as fearfulness or noise sensitivity are still controversial. To better understand the view of breeders, due to an increased interest in maternal care of dogs, an online questionnaire was developed to assess the dog breeders’ profiles and to explore their perception of normal maternal and stress-related behaviors during the peripartum period. In addition, the management of the female during this critical time was queried. Three-hundred and forty-five French dog breeders, representing 91 breeds, completed the online survey. Considering the demographics of the responders, breeding activity in France is mostly family-based with 76% raising two breeds of dogs that produce, on average, five litters/year. Around 60% of the breeders use progesterone levels to determine breeding date. The whelping date is estimated using multiple criteria and most labors and deliveries happen under human supervision. The majority of behaviors associated to good maternal care are defined by the vast majority as being related to more attention of the bitch towards the puppies with the frequency of nursing and licking being important clues. Globally, the peripartum is perceived as a stressful period and to minimize stress and reassure the bitch the favored method used is increasing human presence. Problems related to maternal behavior were described, notably with primiparous bitches.
Breeding soundness evaluation (BSE) is the primary assessment for determining the reproductive potential of male animals. This method, however, cannot be used to evaluate semen frequently or to predict future semen quality. Computerized analysis of ultrasonographic images provides information on histophysiological changes in male reproductive organs. We hypothesized that: (i) semen parameters would correlate with ultrasonographic characteristics of the distal region (cauda) of the epididymis and (ii) testicular ultrasound images and/or circulating testosterone concentration would predict future semen quality in the ram. Six adult rams underwent BSE and scrotal ultrasonography approximately 60 d apart (average duration of the spermatogenic cycle) both during the breeding (December and February) and non-breeding (June and August) seasons. An inverse correlation was found between pixel intensity (numerical pixel values) of the epididymes and percentage of sperm in semen with normal morphology (r = -0.46, P < 0.05). Pixel heterogeneity (standard deviation of pixel values) correlated negatively with percentage of sperm with normal morphology (r = -0.42, P < 0.05) and directly with percentage of spermatozoa with abnormal tails (r = 0.43, P < 0.05). Pixel heterogeneity of testicular parenchyma obtained approximately 60 d prior to semen evaluation inversely correlated with percentage of sperm with normal morphology (r = -0.73, P < 0.01) and sperm progressive motility (r = -0.76, P < 0.01), and directly with percentage of sperm with abnormal tails (r = 0.72, P < 0.01) and loose heads (r = 0.79, P < 0.01). We concluded that scrotal ultrasonography combined with computer-assisted analyses of epididymal and testicular echotexture in the ram was a valuable method for determining certain current and future semen parameters, respectively.
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