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1.
The objective of this study was to examine the effect of donor breed on pronuclear‐stage embryo yield to be used for DNA microinjection in a transgenesis goat program. Twelve Canindé and twelve Saanen goats were heat synchronized using a progestagen‐cloprostenol treatment. Forty‐eight hours before the sponge removal, superovulation was induced with a total administration of 4.4 mg/kg bodyweight NIH‐FSH‐P1, given twice daily in decreasing doses over 3 days. In addition, goats received 100 μg of GnRH and they were hand‐mated at 36 and 48 h after progestagen removal. Embryo recovery was performed by oviduct flushing at 72 h after sponge removal. Embryos were microinjected with a DNA construct and noticeable swelling of the nuclei was the criterion for successful microinjection. The total diameter, cytoplasm diameter, zona pellucida thickness and pronuclei diameter were measured for each microinjected embryo. A higher (p < 0.05) percentage of fertilized ova was observed in Canindé (89.9%) than Saanen (36.2%) goats. In addition, Canindé donors produced a higher percentage of pronuclear embryos when compared with Saanen: 72.5% vs 20.6% (p < 0.05), respectively. Successful microinjection was verified in 96.7% and 73.3% of times in Canindé and Saanen embryos, respectively (p < 0.05). Significant differences were observed for all morphometric parameters except for cytoplasm diameter. In conclusion, under our study experimental conditions, Canindé were more efficient than Saanen goats concerning the pronuclear embryo yield and manipulation. The use of Canindé goats in transgenesis programs could be increase the interest in their breeding and could be contribute to saving them from extinction.  相似文献   
2.
This study examined germination and dormancy in Galeopsis speciosa (Lamiaceae), a common summer annual weed in cold‐temperate areas. Seeds collected in southern Sweden were subjected to several experiments. The seeds were dormant at maturity. Seeds sown outdoors after collection produced a small number of seedlings that emerged early in the spring. After long cold stratification or stratification outdoors over two winters, the maximum germination was 40–50%; germination occurring over a wide range of temperatures. Warm stratification preceding cold stratification had no effect on germination, but repeated warm and cold periods seemed to promote germination. Gibberellic acid (GA) stimulated germination, but full germination was only achieved after more than 2 months of incubation at the most suitable temperature regime tested. Excised embryos grew and developed into normal seedlings. With these results, the species does not fit into the currently used system for seed dormancy classifications. The response to GA and the growth of excised embryos indicate non‐deep or intermediate physiological dormancy, but dormancy alleviation by stratification was not in line with the guiding principles for these classifications. Galeopsis speciosa has a strong dormancy that is sufficiently alleviated during the winter to allow germination of only part of a seed batch each year; hence a stepwise germination pattern occurs over a period of several years.  相似文献   
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A massive unilateral scrotal pyocele caused by Staphylococcus capitis in a 6‐year‐old ram is reported. Ultrasound examination of the right hemiscrotum showed an irregular hyperechoic mass in an anechoic fluid. A dense exudate was collected from the scrotum for microbiological analysis. Grossly, there was an extensive greenish purulent exudate and a completely atrophied right testis. Coagulase‐negative S. capitis was isolated in pure culture. To the authors' knowledge, this is the first report of genital infection by S. capitis in rams. This microorganism should be included in the differential diagnosis of ovine genital infections.  相似文献   
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Protozoological and physicochemical analyses were performed in a waste stabilization pond at Sto. Tomas Atzingo, a small town near Mexico City, in order to discern the internal dynamics of the pond water through the study of the spatial distribution pattern of flagellates and the parallel water volume distribution pattern of some selected physicochemical determined parameters. The statistical method applied to the data obtained was by cluster analysis. The results showed a slight trend to heterogeneity in the system, when it was evaluated through the physicochemically determined parameters. On the other hand, the spatial distribution pattern of the flagellates pointed out a remarkable heterogeneity in the pond. In systems like the one studied where the main feature is an organic matter overload, such a difference in findings indicates a low correlation between the biological parameters, in this case the flagellates, and the physicochemical variables, that should be considered when evaluating the water quality of such systems, either through the physicochemical, the biological or both scopes.  相似文献   
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A protozoological survey was performed on a waste-stabilization pond to isolate, identify, and determine the incidence of ciliates present in these waters. The correlation between the species found and the physicochemical parameters was investigated. One hundred and eighty samples were analyzed from February 1983 to February 1984. Free-living ciliates isolated include:Carchesium polypinum Linnaeus,Vorticella microstoma Ehrenberg,Vorticella convallaria Linnaeus,Didinium balbiani Fabré-Domergue,Amphileptus claparedei Stein,Spathidium spathula Müller,Litonotus fasciola Ehrenberg,Paramecium caudatum Müller,Paramecium aurelia Ehrenberg,Tetrahymena vorax Kidder,Tetrahymena pyriformis Ehrenberg,Cyclidium glaucoma Müller,Aspidisca costata Ehrenberg, andStylonychia putrina Stokes. The performance of the pond was predominantly anaerobic. The temperature, total alkalinity, and nitrate concentration were the most variable parameters in the system studied.  相似文献   
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Three terrestrial leaf meals, Carica papaya, Leucaena leucocephala, Moringa oliefera and a freshwater aquatic fern, Azolla pinnata were evaluated as potential ingredients for farmed abalone diet. All diets were formulated to contain 27% crude protein, 13% of which was contributed by the various leaf meals. Fresh seaweed Gracilariopsis bailinae served as the control feed. Juvenile Haliotis asinina (mean body weight=13.4±1.6 g, mean shell length= 38.8±1.4 mm) were fed the diets at 2–3% of the body weight day–1. Seaweed was given at 30% of body weight day–1. After 120 days of feeding, abalone fed M. oliefera, A. pinnata‐based diets, and fresh G. bailinae had significantly higher (P<0.01) specific growth rates (SGR%) than abalone fed the L. leucocephala‐based diet. Abalone fed the M. oliefera‐based diet had a better growth rate in terms of shell length (P<0.05) compared with those fed the L. leucocephala‐based diet but not with those in other treatments. Furthermore, protein productive value (PPV) of H. asinina was significantly higher when fed the M. oliefera‐based diet compared with all other treatments (P<0.002). Survival was generally high (80–100%) with no significant differences among treatments. Abalone fed the M. oliefera‐based diet showed significantly higher carcass protein (70% dry weight) and lipid (5%) than the other treatments. Moringa oliefera leaf meal and freshwater aquatic fern (A. pinnata) are promising alternative feed ingredients for practical diet for farmed abalone as these are locally available year‐round in the Philippines.  相似文献   
10.
Chronic enteropathy (CE) in dogs is common worldwide, but little data is available from Australia. The aim of this study was to describe treatment response and long‐term outcome in a cohort of dogs with CE. Dogs were prospectively enrolled at Murdoch University and the University of Melbourne. After diagnostic investigation to rule out diseases other than CE, dogs underwent sequential therapeutic trials until achieving a clinical response (diet then antibiotics, and finally immunosuppressants). Success was defined as 75% reduction of clinical severity for a minimum of five weeks. A total of 21 dogs were enrolled, and 19 completed the study. One dog was euthanised for lack of response to treatment and one excluded for lack of owner compliance. Most dogs responded to diet (n = 10), followed by antibiotics (n = 7) and immunosuppressants (n = 2). Long‐term remission (median 21.1 months, [3.0‐44.7]) was achieved in eight out of ten dietary responders without additional treatment. In contrast, only two dogs with antibiotic response remained in long‐term remission, of which one needed on‐going antibiotic treatment. Longer term remission was achieved in the two dogs treated with immunosuppressants with on‐going low dose therapy. This study concludes that most dogs referred for CE in Australia respond to dietary treatment (even after previous dietary interventions), and remission is long‐term compared to dogs treated with an antibiotic. Furthermore, the need for long‐term antibiotics in some dogs to maintain response may lead to antibiotic resistance. This study supports adequate dietary trials for CE in dogs, and a need for alternative second‐line treatments.  相似文献   
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