977 resultados para Reproductive parameters


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Objective. Assessment of genetic parameters for accumulative productivity trait (ACP) and genetic correlations with age at first calving (AFC), between calving interval of first and second parity (BCI1) and longevity (LONG). Materials and methods. 8584 Brahman female records were used with an animal model in multi-trait analysis with restricted maximum likelihood method, implemented using the WOMBAT software. The models considered the fixed effects of contemporary group, parity and weaning weight of first calf covariate, the only random effect was the genetic additive direct. Weaning weight (P240) was included to reduce the effect of selection on the estimation of variance components. Results. The heritability estimates were 0.3 +/- 0.04, 0.11 +/- 0.03, 0.07 +/- 0.03 and 0.24 +/- 0.04 for AFC, BCI1, LONG and ACP respectively. Correlations between ACP and the other features were moderate to high and favorable. Conclusions. ACP can be included in breeding programs for Brahman, and used as selection criteria for its moderate heritability and genetic correlation with reproductive traits.

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This study aimed to verify the preference and infestation level of Anastrepha fraterculus (Diptera: Tephritidae) [South American fruit fly] in fruits of guava cultivars and to correlate them to variables such as peel coloration, soluble solids and pH of fruit cultivars. The following cultivars were used: Pedro Sato, Paluma, Casco and S,culo XXI. The infestation was evaluated in cages, considering two scenarios: no-choice and multiple choice. In both tests, evaluations of the fruit attraction to insects were conducted for a period of 1', 3', 5', 10', 20', 30', 1 h, 2 h, 6 h, 12 h and 24 h. The visit of A. fraterculus on the assayed cultivars in relation to the time was studied by logistic regression. After 10 days, the number of larvae in each fruit was recorded. In the multiple choice test, the visit proportions were significantly higher in the fruits of cvs. S,culo XXI and Pedro Sato than in those of cvs. Paluma and Casco. In the no-choice test, the visit proportions were significantly lower in the Paluma fruits. In both tests, the rate of fruit infestation by A. fraterculus did not differ among cvs. Pedro Sato, Paluma and Casco, whereas the fruits of cv. S,culo XXI were more infested. The indexes of pH did not interfere with the infestation of A. fraterculus, whereas a high rate of soluble solids and low color angle appear to be crucial for discriminating the fruits of the most susceptible cultivars. Infestation rate of S,culo XXI fruits displayed significant correlations with: A degrees Brix (r= 0.7078) and color angle (h) (r= -0.9499) of guava fruits under the multiple choice conditions.

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Population parameters of the shrimp Xiphopenaeus kroyeri (Heller, 1862) (sex ratio, length-frequency distributions (carapace length, CL), growth, lifespan, size of sexual maturity, spawning and recruitment) were analyzed in a long-term study from January 1998 through June 2003. The data on these parameters were collected and analyzed to test the hypothesis that the main period of juvenile recruitment in the bay coincides with the period of fishery closures currently designated by the Brazilian Institute of Environment and Renewable Natural Resources. Monthly collections were conducted along the southeastern Brazilian coast, using a shrimp fishing boat with “double-rig” nets sampling at stations up to 40 m depth. Sex ratios were female-biased only in zones with high reproductive activity such as in stations deeper than 15 m (χ2 test, p<0.05). The mean size of males and females was 15.3 ± 3.1 mm CL and 16.2 ± 4.7 mm CL, respectively, with size at sexual maturity estimates (CL50) of 14.8 mm for males and 15.5 mm for females. Mean growth curves provided estimates of CL∞ = 29.31 mm, k = 0.009/day, t0=−0.25 and CL∞ = 35.33 mm, k = 0.006/day, t0=−0.23 for males and females, respectively, and average lifespans of 1.35 for males and 2.12 years for females. Recruitment and abundances of reproductive females were highly correlated with the environmental factors such as higher water temperature and finer-grained bottom sediment (canonical correlation, r=0.63, p<0.001). The reproductive peaks in February-April 1998, March-May 1999 and February-May 2002 were followed by recruitment peaks in May-July 1998, July-September 1999 and April-June 2002, respectively. Thus, the proposed period of fisheries closure (March to May) does not coincide with the main recruitment periods observed for X. kroyeri.

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

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

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

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

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Ethnopharmacological relevance: Trichilia catigua is broadly used in folk medicine due to its mental and physical tonic activities and stimulant effects. In animal models, its antidepressant-like effects have been associated with the dopaminergic (DA) system modulation, which has an important role on maternal behavior and male offspring reproductive development.Aim of the study: Since little is known about the adverse effects of the exposure to T. catigua crude extract (CAT) in rats, specially regarding maternal homeostasis and offspring development, the aim of the present study was to evaluate whether CAT exposure may influence maternal toxicity parameters and behavior or disrupt male offspring physical and reproductive development.Material and methods: Dams were treated daily (by gavage) with 400 mg/kg of CAT or vehicle (control=CTR) throughout pregnancy and lactation. Fertility and maternal behavior tests were conducted in dams. Male offspring reproductive and behavioral parameters were analyzed.Results: Dams exposed to CAT showed increased pre- and post-implantation losses rates when compared to CTR group. No significant changes regarding maternal behavior or male offspring parameters were observed.Conclusion: In conclusion, maternal exposure to CAT interfered with implantation during the initial phases of pregnancy but did not induce changes on maternal behavior or male offspring reproductive and behavioral parameters.

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Eight reproductive rams with no prior reproductive disease were distributed into three groups of infection with T. gondii: GI, 3 rams, 2.0 x 10(5) P strain oocysts; GII, 3 rams, 1.0 x 10(6) RH strain tachyzoites; GIII, 2 control rams. Clinical parameters were measured and serological evaluations (IIF) were performed. Presence of the parasite in the semen was investigated by PCR and bioassay techniques. The rams presented clinical alterations (hyperthermia and apathy) related to toxoplasmosis in both groups infected with Toxoplasma gondii. All the inoculated rams responded to antigenic stimulus, producing antibodies against T. gondii from postinoculation day 5 onwards. In ovine groups I and II, the greatest titers observed were 1 : 4096 and 1 : 8192, respectively. In semen samples collected from these two groups, the presence of T. gondii was detected by bioassay and PCR. This coccidian was isolated (bioassay and PCR) in tissue pools (testicles, epididymis, seminal vesicle, and prostrate) from two rams infected presenting oocysts and in one presenting tachyzoites.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Interferon-alpha (IFN- α ), a type I IFN, is a protein with antiviral, antiproliferative, and immunoregulatory activities, widely used in the treatment of several types of cancers as well as hepatitis B and C. Decrease of libido and erectile dysfunction are commonly reported by male patients during treatment of chronic hepatitis C with IFN- α . However, IFN therapy-associated underlying factors attributed to sexual dysfunction are still not well defined. Currently, there are few studies investigating the effects of IFN on male reproductive system functions. Given that, the aim of the present investigation was to examine effects of subchronic exposure to IFN- α (5 × 10(4) U/kg and 10 × 10(4) U/kg, 30 d) on serum hormones, sperm parameters, fertility, and testicular and epididymal hystopathology and morphometry in adult male Wistar rats. None of the evaluated parameters was markedly altered by IFN- α . Thus, our results suggest that exposure to IFN- α , in this experimental design, did not adversely affect sperm quality and fertile capacity of male rats.

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Objectives: The objective of this study was to evaluate physical and sexual development and reproductive physiology in female rat offspring that developed in hyperglycemia conditions in utero and during lactation. Materials and methods: Maternal diabetes was induced in female rats by a single IV injection of streptozotocin before mating. Female offspring development was evaluated by means of the following parameters: physical development; age of vaginal opening and first estrus; weight and histological evaluation of uterus and ovaries; duration of the estrous cycle, sexual behavior, and fertility after natural mating. Results: In the female offspring, maternal diabetes caused delays in initial physical development; diminution in ovary weight and number of follicles; and inferior reproductive performance compared with the control group. Conclusions: The exposure to hyperglycemia in uterus and during lactation caused delays in physical and sexual development, and affected the reproductive physiology of female rats negatively.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)