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31.
为满足生产批量化要求,用牦牛睾丸细胞代替犊牛睾丸细胞,接种G0-BT弱毒株,收获,加适当保护剂,经冷冻真空干燥制备羊传染性脓疱皮炎疫苗。结果半成品及成品检验均符合《规程》标准,取得了良好的效果。  相似文献   
32.
This study aimed to evaluate sex, the number of lambs per birth, and the family effects on production traits in the Santa Ines breed of sheep by estimating the least square means and coefficient of variance for those traits. A total of 484 lambs were evaluated for the following traits: weight at birth, at weaning, and at 240 days of age; weight gain during the pre-weaning and post-weaning periods; height, width, and length of different body regions; and rib eye area and fat thickness between the 12th and 13th ribs. We observed coefficients of variation higher than 10 % for several traits. Generally, males were larger than females (P?P?P?ANOVA.  相似文献   
33.
Testicular vitrification is an alternative to preserve the genetic material of pre-pubertal animals. However, there are few studies on post-vitrification warming. Hence, the aim was to compare the influence of different warming temperatures on vitrified testicular fragments from pre-pubertal cats. The testicles were fragmented and divided into a control group (non-vitrified) and vitrified, using an association between dimethylsulphoxide and glycerol. The vitrified fragments were warmed at 50, 55 and 60°C/5 s. Morphological and morphometric evaluations were carried out using classical histology. Afterwards, the mitochondrial activity was evaluated using Rhodamine 123. The data were expressed in mean and standard error. The differences were considered significant when p < .05. In the histomorphological analysis, the testicular fragment presented seminiferous tubules with poorly developed germinal epithelium, compatible with pre-pubertal animals. The group warmed at 50°C presented similar to the control regarding the maintenance of the integrity of the tubules and cells, without stromal rupture and lamina propria alteration, as well as regarding the maintenance of the junctions between the cells. The group warmed at 55°C showed reduction of the cell junctions, and the one warmed at 60°C had increased detachment of the basement membrane (p < .05). The warming caused a reduction in the tubular diameter inversely proportional and progressive to the increase in temperature, with the highest diameter in the control group and the lowest in the 60°C group. The control group showed a lower incidence of Rhodamine 123, followed in ascending order of the warmings at 55 and 60°C. The higher mitochondrial activity was obtained with 50°C, showing an increase of the metabolic cell function at this temperature. It was concluded that the testicular fragment of pre-pubertal cats presents a better preserved morphology, morphometry and viability when warmed at 50°C.  相似文献   
34.
We tested FSHp, eCG and FSHp + eCG to establish ovum pick-up (OPU) and in vitro maturation method in spotted paca. Eight healthy adult females were subjected to each of four treatments to stimulate ovarian follicular growth. All females were subjected to a hormonal protocol using a single dose of 45 mg of injectable progesterone and single intramuscular injection of 0.075 mg d-cloprostenol on day 6. Ovarian stimulation was carried out as follows: in Group TFE (FSHp and eCG), animals were treated with a single dose of 80 mg of FSHp and 200 IU of eCG intramuscularly on day 6 after the application of progesterone; in Group TF (FSHp), they were treated with a single dose of 80 mg of FSHp intramuscularly on day 6 after application of progesterone; in Group treatment eCG, they were treated with 200 IU of eCG intramuscularly on day 6 after application of progesterone; and in Group TC (saline solution), 1 ml of saline solution was administered to control does. The OPU was performed between 22 and 26 hr after gonadotropin treatments. All recovered oocytes were placed into maturation media and incubated for 24 hr. There were no differences among the mean number of observed follicles, aspirated follicles and oocytes recovered per treatment. Oocyte maturation rates did not differ among groups, except, TF and treatment eCG oocytes had greater maturation rates than TC oocytes. In this study, gonadotropin administration failed to superovulate treated does and increase oocyte retrieval efficiency. Despite the feasibility of the procedure, further studies are needed to develop and refine hormonal protocols for oocyte recovery and in vitro maturation in this species.  相似文献   
35.
During the initiation of neonatal pulmonary respiration, there is an exponential increase in reactive oxygen species that must be scavenged by antioxidant defences. However, neonate and preterm newborns are known to possess immature antioxidant mechanisms to neutralize these toxic effects. The purposes of this study were to compare the development of antioxidant system between preterm and term canine neonates and to evaluate the magnitude of acid–base balance during the initial 4 h of life. A prospective study was conducted involving 18 neonatal puppies assigned to Term Group (63 days of gestation; n = 5), Preterm‐57 Group (57 days of gestation; n = 8) and Preterm‐55 Group (55 days of gestation; n = 5). Neonates were physically examined through Apgar score and venous haemogasometry within 5 min, 2 and 4 h after birth. No difference on amniotic fluid and serum superoxide dismutase (SOD), glutathione peroxidase (GPx) and the marker of oxidative stress (thiobarbituric acid reactive substances; TBARS) was verified. Irrespective of prematurity, all neonates presented low vitality, hypothermia, acidosis, hypoxaemia and hypercapnia at birth. However, term puppies clinically evolved more rapidly than preterm newborns. During the course of the study, premature neonates presented more severe complications, such as prolonged hypoxaemia and even death. In conclusion, premature puppies have no signs of immature enzymatic mechanisms for controlling oxidative stress, although SOD and GPx may participate in achieving acid–base balance. Aside from initial unremarkable symptoms, premature puppies should be carefully followed up, as they are at high risk of succumbing to odds of prematurity.  相似文献   
36.
Cystic ovarian disease (COD) is one of the main causes of infertility in dairy cattle. It has been shown that intra‐ovarian factors, such as members of the insulin‐like growth factor (IGF) system, may contribute to follicular persistence. The bioavailability of IGF to initiate its response by binding to specific receptors (IGFRs) depends on interactions with related compounds, such as pregnancy‐associated plasma protein A (PAPP‐A). The aim of this study was to determine IGFR1 and PAPP‐A expression both in follicles at different stages of development and in cysts, to evaluate the roles in the etiopathogenesis of COD in cattle. The mRNA expression of PAPP‐A was higher in granulosa cells of large tertiary follicles than in cysts, whereas the protein PAPP‐A present in the follicular fluid from these follicles showed no differences. Although no PAPP‐A mRNA expression was detected in smaller tertiary follicles, in their follicular fluid, this protease was detected in lesser concentration than in cysts. The mRNA expression of IGFR1 was lower in granulosa cells from cystic follicles than in those from tertiary ones. However, the protein expression of this receptor presented the highest levels in cystic structures, probably to increase the possibility of IGF response. The data obtained would indicate that animals with COD have an altered regulation of the IGF system in the ovary, which could be involved in the pathogenesis of this disease in cattle.  相似文献   
37.
Genetic Resources and Crop Evolution - Annona coriacea Mart. is a native tree to the savannas of Brazil that produces fruits that have economic, ecological, and dietary potential for use by local...  相似文献   
38.
The objective of the present study was to evaluate the phytotoxic effect of aluminum (Al) in corn plants in nutrient solution under high ionic strength (0.0094 uM) and low ionic strength (0.00001 uM). Regarding the low ionic strengths, nutrient solution was added daily until the end of the experimental period. The findings showed that the pH of the nutrient solution reduced with the increase in Al concentration, under both high and low ionic strengths solutions. Electrical conductivity of the nutrient solution increased with Al concentrations only in the solution with low ionic strength, demonstrating that the plant was more sensible to the element toxicity, thus reducing its growth and absorption of nutrients. The production of the total dry mass of corn was affected by the increase of Al concentration in the solution only under low ionic strengths, which reinforces the greater activity and absorption of the element under such condition.  相似文献   
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40.
Illegal wildlife trade is a widespread activity with direct impacts on biodiversity and street markets are frequently pointed out as hotspots in the wildlife trade route. However, due to its illegal character, it is difficult to accurately estimate how many individuals and how much money are handled by traders. Precise data on the number of individuals and species involved, and the drivers behind the illegal wildlife trade are essential for fighting it. We use the example of the metropolitan area of Recife, in northeastern Brazil, a well-known route of illegal wildlife in the country, to access the extent and impact street markets may have on biodiversity. We present quantitative and qualitative information on the illegal trade of wild birds in eight street markets in the area, indicating which species are preferred and why, estimating the number of animals and the volume of money involved, and quantifying the impact that the removal of those animals may have. We observed a high and diversified species offer, biased towards adult male songbirds, with birds of 15 families and 55 species on sale. Birds are kept in poor conditions and some individuals are sold for as little as US$ 1.00. However, we projected that up to 50,000 wild birds may be sold annually in the markets surveyed, including possibly 16,800 individuals of Sporophila nigricollis (the yellow-bellied seedeater), the most frequently observed species. The activity is profitable and may deal with significant amounts of money (up to nearly US$ 630,000.00/year). The numbers involved indicate that street markets are significant wildlife sinks, with a large and frequently ignored impact that must be taken into account in the control and conservation of the biodiversity, not just in Brazil but elsewhere.  相似文献   
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