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91.
The aim of this study was to investigate caesarean operation (CO) undertaken before the pre-partum decrease of progesterone but following administration of a progesterone receptor antagonist and to evaluate the innocuity of this procedure for the dam and pups. Thirty seven bitches of 15 different breeds, received an injection of 15 mg/kg aglepristone 59 or 60 days after the estimated day of ovulation, determined by progesterone quantitative assays, and caesarean section (CS) was performed between 20 and 24 h after administration. Progesterone remained above 6 nmol/l at the time of CS (mean = 15.75, SD = 3.84). No post-operative clinical complications were reported in any of the bitches. All bitches were able to nurse and feed their puppies in the first 24 h following surgery. No pups showed any signs of prematurity and 5 out of 188 pups (2.6) died in the first 2 weeks after delivery. This small study demonstrates that a CS may be safely and successfully performed an average of 2 days before the expected date of parturition following the administration of aglepristone, without any harmful consequence for the dam and her neonates. 相似文献
92.
Objective To determine the prevalence of mastitis pathogens in high‐producing intensive dairy herds in New South Wales. Design Field survey. Procedure Milk samples from the mastitis‐affected quarter were collected from cows on five high‐producing dairy farms in NSW. The 820 samples were cultured using standard microbiological culture techniques. Results Bacteria or fungi were isolated from 83.3% of samples (683/820). More than two colony types were isolated from 16.7% of samples (137/820), two types from 6.6% (54/820), and one type from 52.3% (429/820). No bacteria were isolated from 24.4% (200/820) of the primary cultures, but enrichment cultures of these samples yielded single colony type bacterial isolates from 36.5% (73/200) of samples. Environmental pathogens, including coliforms, environmental Streptococcus and Staphylococcus spp., made up 91% (555/610) of isolates and accounted for 33.6% (205/610), 41.6% (254/610) and 15.7% (96/610), respectively, of isolates. Escherichia coli accounted for 76.1% (156/205) of the coliform isolates, Streptococcus uberis and Streptococcus dysgalactiae accounted for 32.3% (82/254) and 28.0% (71/254), respectively, of the environmental streptococcal isolates. Contagious pathogens were uncommon, comprising only 2.5% (15/610) of the total isolates. Conclusion The incidence and causes of mastitis are largely influenced by farm management. The relatively high prevalence of coliform mastitis in the intensive high‐producing herds in this survey contrasts with the low incidence reported in surveys of pasture‐based herds in Victoria. If the Australian dairy industry continues its current trend of intensification, coliform intra‐mammary infections may emerge as an increasingly important cause of mastitis. 相似文献
93.
Levy E Mylonakis ME Saridomichelakis MN Polizopoulou ZS Psychogios V Koutinas AF 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2006,35(1):115-118
A 5-year-old, intact male, stray dog was presented in poor body condition, with pallor, muzzle deformity, multiple oozing fistulas with grass awns, bilateral sanguinopurulent nasal discharge and a fleshy friable mass occupying part of the hard palate. A friable mass occupying both nasal cavities was found on rhinoscopy. The dog had moderate nonregenerative normochromic-microcytic anemia, thrombocytopenia, hyperglobulinemia, and hypoalbuminemia. Cytologic preparations of the nasal and oral masses contained a neoplastic population of round cells with intracytoplasmic and extracellular vacuoles. Leishmania amastigotes also were observed, in the cytoplasm of macrophages and, occasionally, within neoplastic cells. A diagnosis of transmissible venereal tumor and concurrent leishmaniosis was made. Treatment with vincristine and allopurinol resulted in complete resolution of clinical signs and disappearance of the masses. The presence of amastigotes in neoplastic TVT cells may suggest an alternative mode of transmission of canine leishmaniosis where these diseases co-exist. 相似文献
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96.
Phosphorus,total ammonia nitrogen and chlorophyll a from fish cages in a tropical lake (Lake Palminhas,Espirito Santo,Brazil)
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Graciele P Venturoti Alexandra C Veronez Rômulo V Salla Levy C Gomes 《Aquaculture Research》2016,47(2):409-423
Cage fish farming in natural and artificial lakes has become increasingly popular in recent years in tropical countries. The most commonly farmed tropical fish species is the Nile tilapia (Oreochromis niloticus L.). The aim of this study was to characterize the concentration of phosphorus, total ammonia nitrogen and chlorophyll a from existing fish farms (FF) in Lake Palminhas, located in Linhares/ES, Brazil. Three transects were drawn from 0 to 500 m from each of the four FF (FF1 to FF4) in the lake during six trials (three in the rainy season and three in the dry season). The lake presented a monomictic‐hot pattern, with stratification during the rainy season. Dilution of the monitored parameters did not occur sufficient over a distance of up to 500 m from the FF. The location of the FF in the lake and the input of N and P were critical to ensure optimal mixing conditions because the worst results was observed for the fish farm (FF1) located on a finger of the lake, where the highest concentrations of total phosphorus and chlorophyll a occurred. It was also noted that there was possible total phosphorus interference between FF3 and FF4. The results of this study demonstrate that Lake Palminhas had a low dilution power, and these findings may inform environmental assessments of cage fish farming in this region, providing instruments that may support environmental control of cage fish farming. 相似文献
97.
D. Levy 《Potato Research》1983,26(4):315-321
Summary The effect of repeated short periods of water stress during the hot season on six potato cultivars was investigated. The number
of tubers per plant tended to decrease in response to water stress in cultivars which had more than 9.8 tubers per control
plant (Désirée, Alpha, Elvira). In the other cultivars, no consistent effect of water stress on tuber number per plant was
observed. Except for Spunta, the percentage of large tubers (>60 g/tuber) was reduced in the water-stressed plants. Consequently,
the average weight of these tubers was greater than that of tubers harvested from the unstressed plants, indicating that the
sink force of the individual tuber was not impaired by drought. However, tuber yield per plant was reduced due to drought
in all cultivars tested.
The smallest decrease in dry matter accumulation as well as the greatest lowering of the osmotic potential in the tuber tissue
was found in Alpha. No consistent effect of water stress on the percentage of misshapen and sprouting tubers was observed,
indicating the marked effect of the high temperature on these traits.
Contribution from the Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel, No 310-E, 1981 series. This
investigation was sponsored by a grant from the Ministry for Development Cooperation of the Netherlands. 相似文献
98.
Summary Diffusive leaf resistance and transpiration rate were assessed in various potato genotypes includingS. tuberosum cvs. Atlantic, Cara, Alpha and Désirée,S. phureja clone PP5, a hybrid of Atlantic X PP5, and two anther-derived tetraploids of PP5. Resistance and transpiration were assessed
with an LI-1600 steady state porometer on well-watered plants and differences in leaf resistance and transpiration rate among
genotypes were obtained. These results imply that water economy may be improved by genotypes exhibiting small water losses.
Transpiration rates calculated by dividing the weight of water transpirted per second by the area of the plant's leaflets,
were lower than transpiration rates of young expanding leaflets assessed with the porometer. Nevertheless, the relative differences
among genotypes were evident and a similar relationship among genotypes was maintained in the two measures. Cv. Alpha had
lower transpiration rates, compared to Cara and Désirée, corresponding with its greater stomatal resistance. 相似文献
99.
100.