鱼粉和动物副产品引起肉鸡肌胃糜烂和肠道病变

从发生肉鸡肌胃糜烂的鸡场中采集厄瓜多尔鱼粉样品进行试验,添加3％时引起50％的肌胃糜烂发生率,添加量为9％时基本上引起100％发生率。本研究中肌胃糜烂的严重程度和发生率都大于肠道病变。碳酸氢钠(0.5％)加入日粮亦未防止鱼粉引起肌胃糜烂和12指肠病变。以玉米筛渣代替玉米亦未影响肌胃糜烂发生率。第二个研究中使用了海洋和动物副产品,结果肠道病变严重。作者认为需要作更多的研究以测定究竟是饲料中的什么物质引起肉鸡肠道病变。看来需要采取措施以在加工和贮存过程中稳定动物性和海产饲料从而防止产生有害物质如过氧化物。

Effects of Different Microbes on Fermenting Feed for Sea Cucumber(Apostichopus japonicus)

The effects of different microbes on fermenting feed for sea cucumber （Apostichopus japonicus） were compared to select the optimal fermentation strain in this study. Saccharomgces cerevisae, Candida utilis, Bacillus subtilis and Geotrichum candidum were independently added into the experimental compound feed, while only saline was mixed with the control feed. The fermentation treatments were inoculated with 10% seed solution under the condition of 25 ~C and 70% water content, which lasted for 5 days to elucidate the optimal microbe strain for fermenting effect. Physicochemical indexes and sensorial characteristics were measured per day during the fermentation. The indexes included dry matter recovery （DMR）, crude protein （CP）, the percentage of amino acid nitrogen to total nitrogen （AA-N/tN）, the percentage of ammonia nitrogen to total nitrogen （NH3-N/tN）, and the ratio of fermentation strains and vibrios to the total microbes, color, smell and viscosity. The results showed that DMR, CP and AA-N/tN of the S. cerevisae group reached the highest level on day 3, but the ratio of fermentation strain was second to C. utilis group. In addition, its NH3-N/tN and the ratio of vibrios were maintained at low levels, and the sensory evaluation score including smell, color and viscosity was the highest in S. cerevisae group on day 3. Therefore, S. cerevisae could be the optimal strain for the feed fermentation for sea cucumber. This research developed a new production method of fermentation feed for sea cucumber.

Pond culture of seaweed Sargassum hemiphyllum in southern China

The seaweed Sargassum hemiphyllum is widely distributed throughout the coastal waters of Asia and has high commercial value. In recent years, its natural biomass has declined due to over-exploitation and environmental pollution. To seek for a feasible way to culture this seaweed efficiently, we designed a simple long-line system in a shrimp pond for the culture during winter, and the growth and nutritional composition of the seaweed were examined. Results show that the cul^re system was durable and flexible allowing S. hemiphyllum to grow vertically offthe muddy bottom of the pond. Although the length of pond- cultured S. hemiphyllum was inhibited by water depth, the weight-specific growth rate （（1.65±0.17）%/d） was nearly three times higher than that of wild plants （（0.62±0.19）%/d）. The crude protein （6.92%±0.88%） and ash content （21.52%±0.07%） of the pond-cultured seaweed were significantly lower than those of the wild plants （9.38%±-0.43% and 26.93%±0.07%, respectively）; however, crude fat （1.01%±0.04%） was significantly higher than that of the wild plants （0.87%±0.02%）. In addition, the nutritional composition of both pond-cultured and wild S. hemiphyllum was comparable to or even higher than those of other common seaweeds being used as food and/or aquaculture fodder. Future studies shall be focused on the impact of environmental parameters on its growth and nutritional composition.

Muscle Aerobic Capacity and Filleting Yield of Farmed Fish Species in the Mediterranean Sea

In the present work, we compared indices of metabolism and feed conversion efficiency of a semi benthic and two pelagic mari-cultured fish species in the Mediterranean Sea. The metabolism of fish species varies according to habitat and ecophysiological adaptations. For example, with increasing depth, some species may exhibit adaptations to lower temperature and hypoxic conditions with a reduction in mass specific metabolic rate. Meagre （Argyrosomus regius） is a semi-benthic fish found at depths between 30 m and 300 m. Sea bass （Dicentrarhus labrax） and gilthead sea bream （Sparus auratus） are semi-pelagic fish species widely cultivated in the Mediteranean Sea. The aerobic metabolic potential and feed conversion efficiency of meagre were very different from the sea bass and gilthead sea bream. Compared to these two semic-pelagic fish species, meagre exhibited less efficient feed conversion rate, fillet yield. The results provide an estimate of the quantity of fish required to produce 1 kg of fillet weight, an estimation which is required for the operational management of fish processing companies and for estimating the wastes of fish processing factories during filleting.