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A corneo-conjunctival dermoid is reported in a blue-fronted Amazon parrot ( Amazona aestiva ). After laminar keratectomy, histology showed the epidermis with feather follicles and dermal connective tissue with lymph follicles and sebaceous glands.  相似文献   
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After preliminary six week experiments showed that shrimp pond effluent from an intensive culture growout pond had the capacity to nearly double shrimp growth in laboratory tanks, an 18 day experiment was designed to determine if similar results occurred in the presence of high quality feeds. The results presented here corroborate the hypothesis that autochthonous factors in shrimp pond water stimulate shrimp growth. These results revealed that performance of currently available shrimp feeds is greatly improved in the presence of pond effluent, regardless of feed quality. Increased feed performance did not appear to be an artifact of supplemental feed availability in pond effluent. The implications from these experiments are that, even in intensive culture systems (above 40 shrimp per m2), in-situ sources of nutrition play an important role in shrimp growth.  相似文献   
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Florida pompano has been identified as a promising candidate for commercial‐scale aquaculture production, but to date, little information is available regarding captive broodstock spawning characteristics. Genetic markers were tested for their power in monitoring mating outcomes and potential in analysing heritability of rapid growth trait in Trachinotus carolinus. A total of 20 unrelated adults (10 females and 10 males) were chosen for a hormone‐induced mass spawning event. The 515 fastest growing and 485 slowest growing fish of the total 4852 offspring were considered a selected progeny stock, and fish were collected at 45 days post hatch based on their growth traits. Parentage analyses based on the 20 breeders and 1,000 selected progeny were performed using a total of nine microsatellite markers, a 100% assignment rate was achieved, and a four‐marker set was the minimum number for the parentage assignment. The effective breeding number for the selected progeny was 11 (six females and five males), among which three females and two males were predominant contributors with the total contribution of 95.8% and 94.7% respectively. The proportion of fast‐growing offspring from broodfish and each mating cross (sire/dam) was used for detecting whether variation in growth of the offspring was related to parental stocks. Results showed that three adults and their mated combination exhibited the greatest fast‐growing offspring proportion (69.73% and 55.95%). This research provided new information regarding spawning performance and parental contribution during mass spawning events; both important first steps towards developing improved management strategies for captive Florida pompano broodstock.  相似文献   
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Efforts to reduce the cost of growout feeds for aquaculture have traditionally focused on the use of agricultural wastes as direct or indirect nutritional supplements to support semi-intensive production levels. The merits of a low cost, sugar cane bagasse-based feed for semi-intensive production of Penaeus vannarnei were evaluated. Shrimp averaging 0.24 g each were stocked into 200 m2 earthen ponds at 20/m2 and cultured for a 12 week period. Two bagasse-based feed treatments, a manure-based treatment and a no-feed input control, were compared in replicate ponds. One bagasse treatment (artificial manure) was designed to mimic manure and stimulate autotrophic and heterotrophic growth. The other bagasse treatment (bagasse alone plus inorganics) was designed to stimulate primarily autotrophic growth. Both bagasse treatments produced average growth rates of 0.78 g/wk, which were significantly greater than that of the manure treatment (0.57 g/wk). Lack of difference between the two bagasse treatments suggests that additional supplements used in making artificial manure probably were unnecessary to the nutrition of the shrimp. At harvest, bottom organics in the bagasse-fed ponds were at least twice as great as manure-fed ponds, and may have contributed to the lower survival associated with these treatments.  相似文献   
6.
The pharmacokinetic properties of indomethacin and its effects on aqueous protein values were studied in 15 clinically normal Beagles. The dogs were treated every 6 hours with 1% indomethacin suspension in 1 eye, with the other eye serving as a control. After 24 hours, the dogs were anesthetized and samples of aqueous humor (AH) were drawn by aqueocentesis at 0, 15, 30, 60, and 90 minutes after initial paracentesis. Additional samples were drawn at the time of euthanasia, 180 (6 dogs) and 360 minutes (9 dogs) minutes after initial paracentesis. Blood samples were obtained at each treatment and at each aqueocentesis. The eyes were enucleated after dogs were euthanatized. Aqueous protein concentrations and indomethacin concentrations in AH, plasma, and different ocular tissues were determined. Topical indomethacin administration had no effect on baseline protein concentrations of AH. It reduced protein concentrations in AH significantly at all times after initial aqueocentesis. This reduction was approximately 30%. Indomethacin in the AH is mostly protein-bound. Concentrations were 350 ng/ml in primary AH and 1,305 ng/ml in secondary AH, 90 minutes after initial aqueocentesis. Free-drug concentrations were relatively constant at about 220 ng/ml. Indomethacin administered topically is readily absorbed by the ocular adnexae, reaching a steady-state concentration of 25 ng/ml in blood plasma 18 hours after the start of treatment. Plasma concentrations were 50 times lower than therapeutically effective concentrations. High indomethacin concentrations were found in the cornea only. Low concentrations were found in the iris and ciliary body, the lens, and in the choroid.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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A tag-release-recapture study was conducted to evaluate size-at-release impacts upon recruitment of cultured, juvenile striped mullet, Mugil cepahlus released in inshore habitats of Oahu, Hawaii, USA. In June and July 1990, 85,848 juvenile mullet were graded into five size groups (ranging from 45 to 120 mm in length), identified with binary-coded wire tags, and released into two estuaries (2×5 factorial design). Of the tagged fish, 42,822 were released into Kaneohe Bay on the east (windward) coast of Oahu; 43,026 were released into Maunalua Bay on Oahu's dryer south shore. The fish were released into both bays simultaneously. Releases were blocked in time across 5 release lots. To evaluate growth and survival rates of released mullet, both bay systems were sampled monthly with cast nets over a ten-month period after release. Overall, 733 tagged M. cephalus were recaptured, 277 from Kaneohe Bay and 456 from Maunalua Bay. Overall proportions of tagged fish in samples declined from 33.4% (±25.2%) of the total M. cephalus catch at week 5 to 1.88% (±0.95%) by week 23. From week 23 on, tagged fish averaged 2.09% (±0.23%) of the striped mullet in monthly samples. Within 9 wk after releases, recapture frequencies were clearly skewed in favor of fish that were larger at the time of release. Fish smaller than 70 mm when released were rare or absent in collections within 18 wk after release. This confirms results of a smaller-scale pilot study in Maunalua Bay and shows that fish size-at-release can have a major impact on the success of hatchery releases in marine habitats. Pilot studies to identify minimum fish size-at-release should be conducted at all sites targeted for full-scale marine hatchery releases.  相似文献   
9.
A special form of keratitis in the cat is described on the basis of 8 clinical cases. The disease has been known in the United States and the United Kingdom for some time, however, it has, to our knowledge, never been described in Switzerland. This keratitis is characterized by chronicity and infiltration of the cornea by mast cells and eosinophils. It is usually an unilateral and painless condition. We describe the clinical features and diagnostic examinations of the disease. Cytology of a corneal scraping is usually diagnostic. As in the cases described in the literature the cats were successfully treated with oral megestrol acetate. The aetiology of the disease is unknown.  相似文献   
10.
The effects of continuous paddlewheel operation on shrimp growth, yield and crop value were studied in Hawaii. Six 0.4 ha earthen ponds were stocked with Penaeus vannamei at 25 postlarvae/m2. Three ponds served as controls with no mechanical aeration or mixing. Each of the other three ponds had two 1 hp paddlewheel aerators (3.7 kw/ha) running continuously throughout the five month trial (29 April-8 October 1986). All other management factors were applied uniformly.
Daily water temperature and use were significantly different between treatments. Paddlewheel ponds had lower water temperatures (28.3 vs. 28.5 C) and lower water use (0.8% exchange per day vs. 2.2% exchange per day) than control ponds.
Faster shrimp growth in paddlewheel ponds was evident in week 8. At week 14, mean shrimp body weights and growth rates were significantly greater. Shrimp at harvest were 21.2 ± 2.6 g in paddlewheel ponds versus 15.3 ± 2.6 g in control ponds. Mean shrimp production was 2,852 ± 222 kg/ha in paddlewheel ponds compared to only 2,061 ± 558 kg/ha in controls. Mean crop value was $13,719 per pond per crop for paddlewheel ponds versus $9,111 for control ponds. Hence, paddlewheels afforded an increase of 42% in net crop value after subtracting purchase and operating costs.  相似文献   
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