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861.
862.
根据统计资料,利用剩余产量模型专家系统(CLIMPROD)对东海鲐鲹鱼类最大持续产量(MSY)作了评估分析。结果表明:东海鲐鲹鱼类合计分析时的MSY在34.5~44.2万吨之间,接种类分别评估时,鲐鱼的MSY为16.1万吨,蓝圆鲹为22.2万吨;按区域分析时,鲐鲹鱼东海北部群的MSY为12.5~13.2万吨,福建沿海群为20.1万吨。 相似文献
863.
本文阐述了我国对虾养殖生产的基本情况及对虾养殖生产面临的潜在威胁。从科研,生产和销售三个方面提出了一些急待解决的问题和对策,并对我国养虾业发展的前途做了展望。 相似文献
864.
Misa HOSOE Nao YOSHIDA Yutaka HASHIYADA Hidetoshi TERAMOTO Toru TAKAHASHI Sueo NIIMURA 《The Journal of reproduction and development》2014,60(4):268-273
Fetal bovine serum (FBS) has been widely used as a supplement in the maturation medium of bovine oocytes in
vitro. However, serum contains many undefined factors and is potentially infectious to humans and animals. As a serum
replacement, we evaluated the feasibility of using the silk protein, sericin, derived from the cocoons of silkworm. To examine the
rates of oocyte maturation and fertilization, cumulus-oocyte complexes were cultured in TCM-199 supplemented with 0.01%, 0.05%,
0.1% or 0.15% sericin or 5% FBS. The sizes of the perivitelline space that might relate to polyspermy, the expressions of
Has2 and CD44 mRNA, the amount of hyaluronan (hyaluronic acid: HA) contained in the oocytes
and the rates of blastocyst formation following insemination were then compared between the oocytes cultured with 0.05% sericin
and 5% FBS, because the polyspermy rates in oocytes cultured with 0.05% sericin were significantly lower than in those cultured
with 5% FBS. After in vitro maturation (IVM), the mean size of the perivitelline space was significantly greater
in oocytes cultured with sericin than in those cultured with FBS, although the rates of nuclear maturation, fertilization and
blastocyst formation of oocytes under both IVM conditions were not significantly different. The expression of HAS2 and
CD44 mRNA and the amount of HA in the denuded oocytes cultured with 0.05% sericin were significantly greater than in
those cultured with FBS. These results indicate the feasibility of sericin as an alternative protein supplement for IVM in bovine
oocytes. 相似文献
865.
This study explores the chemical composition, buffer N solubility, in vitro ruminal N degradability and in vitro ruminal biological activity of tannins in leaves from Gliricidia sepium, Leucaena leucocephala, Morus alba and Trichanthera gigantea trees. These tree leaves are a potential protein source for ruminants, but their site‐influenced nutritive value is largely unknown. Leucaena leucocephala leaves had the highest N content (42.1 g/kg DM), while T. gigantea leaves had the least (26.1 g/kg DM). Leucaena leucocephala had the highest buffer solubility index (20%), while 10% of the total N in leaves of the other three species was soluble. The rapidly fermentable N fraction ‘a’ was highest in M. alba leaves (734.9 g/kg DM) and least in T. gigantea leaves (139.5 g/kg DM). The rate of fermentation (c) was highest for M. alba (7%/hours) leaves. No significant correlations were recorded between buffer solubility index of N and in vitro ruminal N degradability parameters: a, b, and c. The highest response to tannin inactivation using polyethylene glycol, in terms of percentage increase in 36‐hours cumulative gas production, was recorded in M. alba (39%) and T. gigantea (38%) leaves. It was concluded that buffer solubility of N is not a good indicator of ruminal N degradation in the leaves of these tree species. Leaves of M. alba could be more valuable as a source of rapidly fermentable N when animals are offered low‐protein, high‐fibre diets compared with other tree species evaluated in the current study. However, when feeding M. alba leaves, the role of tannins must be considered because these secondary plant compounds showed significant in vitro ruminal biological activity. 相似文献
866.
D. I. Ayoade E. Kiarie B. A. Slominski C. M. Nyachoti 《Journal of animal physiology and animal nutrition》2014,98(3):569-577
Gaining a detailed knowledge on the impact of a feedstuff on pig growth and physiological responses is critical for its effective utilization. Thus, the purpose of this study was to investigate the effect of distillers dried grains with solubles derived from co‐fermentation of wheat and corn (wcDDGS) on performance, carcass and visceral organ weights, whole‐body O2 consumption and heat production (HP) in growing barrows. The experimental diets were as follows: corn–soybean meal diet (Control), Control + 15% wcDDGS and Control + 30% wcDDGS. In Exp. 1, 48 pair‐housed pigs of average BW 18.6 ± 1.5 kg (mean ± SD) were allotted to the 3 diets (n = 8). Pigs had free access to water and feed for a 28‐day period during which ADG and ADFI were calculated weekly. Thereafter, 1 pig/pen was killed to measure carcass and visceral organ weights. Overall, wcDDGS linearly decreased (p < 0.05) ADFI and ADG but had no effect on G:F (p > 0.10). The ADFI was 1.55, 1.45 and 1.36 kg/day for diets containing 0, 15 and 30% wcDDGS respectively; corresponding values for ADG were 0.79, 0.75 and 0.67 kg/day respectively. A linear decline (p = 0.01) in eviscerated hot carcass weight was observed as dietary wcDDGS increased. In Exp. 2, 18 pigs of average BW 20.4 ± 2.4 kg (mean ± SD) were individually housed in metabolism crates and fed the 3 diets (n = 6) at 550 kcal ME kg BW?0.60day for a 16‐day period followed by measurement of O2 consumption using an indirect calorimeter. Diet had no effect (p > 0.10) on whole‐body O2 consumption and HP. In conclusion, increasing wcDDGS content in growing pig diets linearly reduced ADFI, ADG and eviscerated hot carcass weight but had no effect on G:F, visceral organ weights or HP. 相似文献
867.
采取现场调查和排污系数推算相结合的方法。研究区域内规模养牛粪便和污物的区域分布、污染类型、产生量、排放量及其综合利用情况。表明:区域内牛粪尿年排放总量100.85×104 t,其中:规模养牛粪尿年排放总量29.47×104 t,养牛小区、场和大户各占21.41%、24.49%和54.10%。COD 年排放668.07×104 kg,BOD 年排放432.72×104 kg, NH 3-N 年排放总量为67.79×104 kg,N 年排放量在为65.01×104 kg,P 年排放量为27.50×104 kg。粪便负荷量7.83 t/hm2,占总负荷量21.53 t/hm2的36.37%。年流失量2.38×104 t,占8.08%。进行臭源监测和臭气评价,牛舍内 H2S 0.15 mg/m3,NH 32.77 mg/m3。综合利用率91.92%。 相似文献
868.
青肯泡浮游生物及鱼产潜力 总被引:1,自引:0,他引:1
青肯泡浮游生物共计1 1 3个种属,其中浮游植物63个种属,浮游动物5 0个种属,浮游植物数量2 37 .2 8×1 0 4 ind /L ,生物量2 5 0 0mg/L ,浮游动物数量5 5 0 5 .4ind /L ,生物量6 .692mg/L ,全库总鱼产潜力5 2 7760kg ,总放养量2 80 4 80 0尾。 相似文献
869.
鱼鳞制胶及其综合利用 总被引:16,自引:0,他引:16
鱼鳞很适合提取优质胶。通过酸碱水解和酶促水解的比较,得出酶解工艺更适合鱼鳞制胶,并确定了酶解的最佳条件。鱼鳞胶的应用非常广泛,其副产品也可以利用。 相似文献
870.