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1.
Live hatchery feeds were assayed for fatty acids (FA), amino acids (AA), and their ability to support growth and survival of larval and postlarval mahimahi Coryphaena hippurus at two different hatchery stages. Euterpina acuritrons copepods (C), mahimahi yolk-sac larvae (YSL), Artemia parthenogenica brine shrimp nauplii (BSn), A. parthenogenica juveniles (BSj), and Brachionus plicatilis rotifers (R) were assayed, using several enrichment media. There was little difference in AAs among feeds.
Levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were about 10 times higher in YSL than in their feeds. This explains previous findings where first stage larval survival (0–9 days) was not affected by feed HUFA levels. Second stage survival was significantly higher when larvae were fed copepods. Enrichment with 100 ppm SuperSelco greatly improved the survival of larvae that were fed brine shrimp. The even higher omega-3 fatty acids found in copepods appear to be important for survival of larvae under more stressful conditions.
Brine shrimp juveniles enriched with SuperSelco are a good food for postlarval mahimahi. Yolksac larvae of mahimahi are an even better food, promoting faster growth at less cost, for large scale mahimahi aquaculturists. Different batches of yolksac mahimahi larvae varied by a factor of 10 in their concentration of DHA, but always had the highest level of DHA as much as 40% of total fatty acids (FAs). These "high HUFA" batches of YSL also had the highest levels of EPA and total fatty acids. The data suggest that climate and broodstock age may have considerable influence on larval nutrition.  相似文献   
2.
A high percentage (98.3%, N = 60) of the marbled grouper Epinephelus microdon individuals captured from spawning aggregations during July and August 1993 in the waters surrounding the island of Koror, Republic of Palau, Micronesia, were in the stage of maturity at which final maturation and spawning could be hormonally induced. The sex ratio of the captured fish was highly skewed towards males (4 male:1 female). Sexually immature females comprised the smallest size class, (<0.6 kg body weight (BW) or 33.0 cm total length (TL)), while sexually mature females were restricted to the 0.6–1.5 kg BW (33.0–46.4 cm TL) groups. Males predominated in size classes >0.6 kg BW, and individuals >1.5 kg BW (46.4 cm TL) were exclusively male. All females with oocytes that averaged ( N = 50) >400 μm in diameter were successfully induced to spawn by a two-injection protocol using human chorionic gonadotropin (HCG) at total dosages of 2,100–3,200 IU/kg fish. All males used in the spawning trials were administered a single injection of HCG at dosages of 500 or 1,000 IU/kg fish. Fecundity ranged between 7.96 × 105−1.24 × 106kg BW, average spawned egg diameters ranged between 769–832 μm, percent fertilization ranged between 32.6%–99.9%, and hatching percentages were >90.0%. Total fat content of eggs obtained from a pooled spawning event was 14.1 mg/100 mg dry weight. The data indicate that HCG is a suitable treatment for the induction of spawning in marbled grouper females that possess a mean oocyte diameter of 400 μm or greater.  相似文献   
3.
The present study aimed to determine the effects of different levels of marigold, Calendula officinalis, powder, 0 (control), 0.5% (M0.5), 1.5% (M1.5), and 2.5% (M2.5), on pigmentation and growth performance of the blue gourami after a 70‐day trial. At the end of the experiment, no significant differences (p > 0.05) were found in fish growth performance and body compositions. Color parameters (L*, a*, and b*) were weekly evaluated by examining a point posterior to the fish operculum. The marigold‐fed fish were darker than the control fish at Weeks 9 and 10. Yellowness intensity of the M2.5 was significantly higher than the other treatments at Week 9. Skin and caudal fin total carotenoids, astaxanthin, canthaxanthin, and β‐carotene contents of the treatment M2.5 were significantly different (p < 0.05) compared to the other treatments. Muscle total carotenoids, astaxanthin, and canthaxanthin contents of the marigold‐treated fish were significantly (p < 0.05) higher than the control group. Muscle β‐carotene contents of the treatments M1.5 and M2.5 were significantly (p < 0.05) higher than the control group. This study shows that marigold powder may be considered an efficient natural carotenoid source for pigmentation in blue gourami.  相似文献   
4.
We describe a 5-year-old castrated male dog suspected hypoglycemic encephalopathy that was evaluated by using diffusion-weighted imaging (DWI). The dog experienced hypoglycemia after prolonged generalized and continued partial seizures. In the acute phase, DWI showed hyperintensity in the left temporal lobe. After about a month, DWI maintained hyperintensity, and left middle cerebral artery dilation was noted on magnetic resonance angiography (MRA). In the chronic phase, the left temporal lobe lesion was replaced by cerebrospinal fluid. In humans, it was reported that cortical laminar necrosis (CLN) with hypoglycemic encephalopathy presents hyperintensity in the cerebral cortex on DWI and increased vascularity of the middle cerebral artery branches on MRA. In conclusion, DWI has detected CLN in a dog suspected hypoglycemic encephalopathy.  相似文献   
5.
Veterinary Research Communications - Ceramide (CER), an important component of the extracellular lamellar lipids in the stratum corneum (SC), plays a critical role in maintaining the cutaneous...  相似文献   
6.
Reliable data on the contribution of forests to the livelihoods of households in the Congo Basin are not always readily available to governments and decision-makers. This paper assesses the value of forest resources on livelihoods in Cameroon, Republic of Congo, Gabon, Central Africa Republic and the Democratic Republic of Congo. Data were collected using the Forest Poverty Linkages Toolkit, between 2012 and 2014 on stratified samples of 616 Bantu and indigenous people’s households in 15 villages. The study reveals that forest resources account for 48% to 63% of the total revenue of rural households. In Bantu households, estimates of the gross income from the forest per capita/day range from $US 0.18 to $US 1.3. This value is about double that received by indigenous people except in Congo. Non-cash income is about twice as high as cash income. On average, cash income reaches only about 23% of the World Bank $1.25 a day income level for chronic poverty. However, non-cash income - about twice as high as cash income – mitigates these profound poverty levels to some extent. The paper concludes by considering the importance of the findings for policy-making in Central Africa and the Congo Basin, and more widely. It is suggested that much more data of this kind is need to shape appropriate approaches to sustainable forest management, with a better understanding of the economic security and the livelihood resilience of the chronic poor increasingly kept in mind.  相似文献   
7.
Thirty five villages randomly selected across ethnic and agro-ecological zones of Benin were surveyed to document the indigenous knowledge associated with the domestication (bringing into cultivation), production and utilization of vegetable Gbolo (Crassocephalum spp.). The study revealed the existence of different morphotypes (1–4 per village) corresponding to two botanical species (Crassocephalum rubens (Juss. ex Jacq.) S. Moore) and (Crassocephalum crepidioides (Benth.) S. Moore) found unequally distributed throughout the country. The domestication (bringing into cultivation from the wild) of Gbolo was started in many villages and with some tribes in southern Benin, the vegetable is already being produced in sole cropping for commercial purposes. Regular consumption (49.90 % of responses) and scarcity (20.30 % of responses) were the two main reasons attributed by the interviewees for domestication of the vegetable. The cultural practices recorded were of five categories. The commonest cropping system found was mixed or inter-row cropping (92.31 % of producers) with either vegetable crops (53.85 % of producers) or non-vegetable crops (38.46 % of users). Sauce prepared with either fresh or dried leaves was the main type of preparation of Gbolo and the vegetable was reported to possess special nutritional and medicinal values. For further promotion, important researches directions are suggested.  相似文献   
8.
Limited water exchange production systems for freshwater ornamental fish   总被引:1,自引:0,他引:1  
Two biofilter designs and a control were tested in triplicate to determine if inexpensive bioremediation devices could increase production and decrease water use on ornamental fish farms in Hawaii. Koi (Cyprinus carpio L.) were used as the model species and the experiment was conducted outdoors in greenwater. When fish density was 9.7 kg per 2.08 m3 and they were eating 125 g day?1, the 20 L trickle filters were able to maintain acceptable water quality. Tanks with the same size submerged filters suffered significantly lower dissolved oxygen levels compared with tanks with trickle filters and control tanks with no biofilters exhibited significantly higher nitrite‐nitrogen (about 20 mg L–1) and nitrate levels (about 400 mg L–1). As typical ornamental fish weigh 3 g, the trickle biofilter system described here can produce 1.55 fish L?1 (compared with the industry standard 0.25 fish L?1) and use very little water other than the water originally in the tanks.  相似文献   
9.
This study was conducted to evaluate dietary protein and carbohydrate requirement of juvenile Hawaiian limpets Cellana sandwincensis. A total of 64 juvenile limpets (3.12 ± 0.86 g) were fed five different dietary protein levels ranging from 270 to 470 g kg?1 for 90 days. Carbohydrate and lipid levels were held constant at 180 and 49.7 g kg?1, respectively. Weight gain and growth rates of the animals did not differ significantly (P > 0.05) among the protein levels ranging from 270 g kg?1 (0.30 % day?1) to 470 g kg?1 (0.23 % day?1). Next, opihi were fed four diets with protein levels from 210 to 500 g kg?1 with a constant carbohydrate level at 120 g kg?1. Weight gain and specific growth rates of opihi increased with increasing dietary protein from 210 to 350 g kg?1, and significantly (P < 0.05) decreased at the 500 g kg?1 diet. Highest weight gain, growth rates, and protein efficiency ratio were achieved at 350 g kg?1. Elevated carbohydrate levels (180–370 g kg?1) produced a significant difference (P < 0.05) in growth. The fastest growth rates of animals were obtained with 270 g kg?1 (0.27 % day?1) and 320 g kg?1 (0.26 % day?1). The weight gain of animals fed 180 and 370 g kg?1 carbohydrate diets were significantly (P < 0.05) lower than those of animals fed 270 and 320 g kg?1. We conclude that about 350 g kg?1 protein and 320 g kg?1 carbohydrate levels could be used for opihi.  相似文献   
10.
This study investigated the effect of dietary arachidonic acid (ARA, 20:4n‐6) on final maturation, spawning performance and composition of the gonad of black sea urchin (Diadema setosum). Four different dietary ARA levels of 0.3 g/kg (Control diet), 1.4 g/kg (ARA 1.4), 2.5 g/kg (ARA 2.5) and 3.7 g/kg (ARA 3.7) were prepared and tested in this feeding trial for 90 days. The result showed that growth in terms of weight was not relatively affected by dietary ARA. Gonadosomatic Index (GSI) of animals were gradually increased in all the diets throughout the trial. The highest GSI level (25.7 ± 3.16%) was observed in animals fed with the diet ARA 1.4. ARA content in the gonad proportionally increased with dietary ARA levels. The highest larval survival rate (85.5 ± 5.67%) was found in diet ARA 2.5. The results of this study indicate that ARA plays an important role in the reproduction functions of black sea urchin and supplementing an appropriate level of ARA in the broodstock diet could induce the final maturation and improve reproduction of black sea urchin, but a higher level of ARA (3.7 g/kg) seems to have a negative effect on both growth rate and GSI.  相似文献   
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