Effect of bovine colostrum intake on growth,reproductive parameters and survival in red kids

The aim of this study is to evaluate the efficacy of frozen Azawak colostrum supplementation on body weight (BW), average daily gain (ADG), reproductive parameters (mean age at first parturition, fertility, fecundity, prolificacy) and mortality rate among red kids. The study was conducted at the goat farm secondary centre of Maradi in Niger from September 2010 to September 2011. The control animals (n = 20) were left with their mother, while the treatment animals (n = 20) received in addition 50 ml/animal/day of bovine colostrum at birth and 15 ml/animal/day from d2 to d15. Weight was measured weekly from birth to d365. Mortalities were also recorded over the same period. For reproductive parameters, observations began at weaning (d197). Growth rate was higher (p < 0.001) in supplemented animal, and the treatment effects on ADG were observed up to 150 day after the end of supplementation. A similar long‐lasting trend was also observed in relation to the mortality rate (25% for ColG vs. 55% for ConG; p = 0.05). The age at first kidding tended to be lower in the treated group (13.8 ± 0.7 vs. 14.1 ± 0.8 month; p < 0.1). In conclusion, mild bovine colostrum supplementation induces a long‐lasting positive impact on growth rate and to a lower extent on reproduction parameters and survival rate.     

日本对虾仔虾的温度适宜性实验研究

日本对虾 (Penaeusjaponicus)仔虾体全长 (11 7± 1 0 )mm ,分别置于 2 4,2 0 ,18,16 ,14 5 ,13℃水槽中培养 ,经 10d观察的结果 :仔虾成活率与水温呈负相关 ,依次为 0 12 ,0 2 8,0 39,0 5 3,0 5 3,0 6 0 ;长度增长率与水温呈正相关 ,依次为 0 2 7,0 19,0 12 ,0 0 9,0 0 4,0 0 1。认为仔虾放流海区水温应 >16℃。     

使樱花赏花期延长的日本引种品种的选育搭配研究

对武汉法雅园林集团有限公司从日本引进的39个樱花品种的成活率和花期进行了观测研究,筛选出了23个成活率在80%以上的花期不同的品种,为园林绿化工程中延长樱花赏花期的品种搭配设计提供参考依据。     

美国竹柳在临沧市的引种试验

从昭通市引进美国竹柳进行插条扦插育苗、营养袋苗上山造林试验。结果表明,扦插育苗未用药剂处理,成活率达100%。在保证水湿条件,只施一次肥的粗放管理条件下,7个月苗高达1.5~2.5 m,地径1~2 cm。在造林后只铲一次草的粗放管理条件下,裸根苗在洼子地造林的成活率较高,达90%,在干旱坡地造林的成活率低,仅为17%;组培营养袋苗在干旱坡地造林的成活率最低,仅为10%。造林1年后,组培营养袋苗在干旱坡地的年均树高和地径生长量为28.1 cm和0.32 cm;扦插裸根苗在洼子地的年均树高和地径生长量为74 cm和1.7 cm;扦插裸根苗在干旱坡地的年均树高和地径生长量为30 cm和0.4 cm。试验表明:水湿条件或灌溉条件是保证美国竹柳引种成功的关键。     

不同盐度海水对锯缘青蟹幼蟹生长变态的影响

实验室条件下比较了盐度为0、3.38‰、6.76‰、10.14‰、13.52‰、16.99‰条件下锯缘青蟹由二期幼蟹至六期幼蟹的生长变态情况。初步结果表明:青蟹幼蟹在变态为四期幼蟹之前,对环境盐度条件有较高的要求:盐度低于10‰,将延长其变态周期和降低成活率;四期幼蟹以后对盐度的适应能力明显增强,此阶段适当降低盐度,将有助于缩短其蜕壳周期。     

急性温度胁迫对大口黑鲈存活率及肝脏生化指标的影响

为了探究急性高温胁迫对大口黑鲈(Micropterus salmoides)“优鲈3号”存活率及肝脏生化指标的影响,将25℃(对照组)下暂养的大口黑鲈“优鲈3号”直接放入31、34、37℃水环境中,测定不同温度应激后鱼体的存活率及肝脏生化指标。结果表明:37℃组成活率低于31℃、34℃组,仅为50%。31℃和34℃组T-SOD、GSH-PX、CAT、LZM、AKP和ACP活力在48 h显著高于对照组。37℃组则与对照组无显著差异,且ACP活力在48 h显著低于对照组。结果表明,在培育大口黑鲈“优鲈3号”鱼苗时温度应该保持在34℃以下。     

酸碱度和干露对墨西哥湾扇贝幼虫和稚贝的影响

为探讨酸碱度和干露对墨西哥湾扇贝不同发育阶段的影响,2000年4月和2001年4月在浙江省玉环县抛西水产育苗场用实验生态的方法研究了酸碱度和干露对墨西哥湾扇贝浮游幼虫和稚贝生长和存活的影响。结果表明:pH值7～8存活率最高,生长最好。稚贝的耐干露能力低下。     

Ca^2＋、Mg^2＋对凡纳滨对虾存活及生长的影响

通过单因子静态急性毒性试验和正交设计法,研究水环境中Ca~(2 )、Mg~(2 )、Ca~(2 ) Mg~(2 )总量及Ca~(2 )/Mg~(2 )比值对凡纳滨对虾存活及生长的影响。结果表明:(1)凡纳滨对虾48h的Ca~(2 )的LC_50为407.38mg·L~(-1)、Mg~(2 )的LC_(50)为741.31mg·L~(-1)。(2)在Ca~(2 )/Mg~(2 )比值为1:10时,对凡纳滨对虾生存没有影响;(3)凡纳滨对虾的生长与Ca~(2 )浓度有密切关系,其值过高或过低均会影响凡纳滨对虾的生长;在Ca~(2 )/Mg~(2 )比值为1:3时,凡纳滨对虾生长和存活率随着Ca~(2 ) Mg~(2 )质量浓度的增加而上升,但达到一定质量浓度后,又随着Ca~(2 ) Mg~(2 )质量浓度的继续增加而下降。     

Preliminary observations on the tank and pond culture of the glass eels of the Australian shortfin eel, Anguilla australis Richardson

There is expanding interest in the culture of the Australian shortfin eel Anguilla australis Richardson; however, there is a lack of fundamental biology and husbandry information necessary to further develop an industry within Australia. The present study was undertaken to gain a preliminary understanding of basic husbandry requirements for rearing of juvenile A. australis (glass eels and elvers) in tanks and earthen ponds. Newly caught glass eels were successfully acclimated to culture conditions. During tank culture trials, specific growth rates (SGR) and survival rates ranged from ?2.1 to 2.8% day^?1 and 52% to 100% respectively. Glass eels weaned onto a commercial eel diet exhibited a significantly greater SGR and survival rate than those weaned onto a commercial trout diet. Glass eels weaned onto an eel diet over a 15‐day period grew slightly faster than eels weaned over a 5‐day period, but survival rates were not significantly different for each treatment. SGRs (up to 2.8% day^?1) were significantly higher for glass eels fed at 9 and 12% day^?1 than at 6% day^?1. Stocking densities between 2.5 kg m^?3 and 30 kg m^?3 did not influence either SGR or survival rates. SGRs were significantly higher for glass eels cultured at 25 °C than at lower temperatures. During pond culture trials, SGRs and survival rates ranged from 1.36 to 1.65% day^?1 and 39% to 77% respectively. The SGR and survival rates of juvenile eels stocked into ponds receiving supplementary feeding with a commercial eel diet were not significantly different to those of eels stocked into ponds that did not receive supplementary feeding.     

Spatial and temporal trends in abundance of Atlantic salmon, Salmo salar, in Newfoundland with emphasis on impacts of the 1992 closure of the commercial fishery

Closure of the Newfoundland commercial Atlantic salmon, Salmo salar L., fishery in 1992 was the most restrictive measure introduced to help rebuild depressed local stocks of salmon. Here, the effects of the closure are evaluated by analysing trends in abundance since 1984, and estimates of survival in both freshwater and marine environments derived from enumeration of salmon at fish counting facilities. While freshwater production of smolts generally has been maintained, marine survival rates remain low (2–10%), and highly variable. Overall, total stock size differs little from that prior to the closure of the commercial salmon fishery. Spawning escapements have increased by a factor of 2 or 3 in some rivers, but in other areas total returns are lower on average than those prior to the fishery closure. Factors other than exploitation are contributing to lack of stock recovery, resulting in continued conservation concerns.