High‐oil residue camelina meal,a viable source of protein at low levels in diets for juvenile salmonids

The oilseed Camelina sativa has been studied as a lipid source for farmed salmonids, but recommended inclusion as a protein source has not been determined. This study evaluated low inclusion of camelina high‐oil residue meal (HORM) at 20, 40 and 60 g/kg of the diet, to determine an adequate level for Atlantic salmon parr (Salmo salar) and rainbow trout (Oncorhynchus mykiss). Salmon and trout were fed experimental diets containing up to 60 g/kg HORM for 16 weeks. At 40 g/kg HORM, trout and salmon growth performance were similar to those fed a control diet. However, at 60 g/kg HORM, trout showed lower final weight, weight gain and feed intake than those fed the control diet. Rainbow trout fed 40 and 60 g/kg HORM showed significantly lower whole body ash (p = .005), slightly lower whole body protein levels and higher fat than the control. In salmon fed 60 g/kg HORM diets, whole body ash (p = .024), and the submucosal layer of the intestine was thicker than the control (p = .007). Current results indicate that up to 40 g/kg HORM can be included in diets for rainbow trout and salmon juveniles.     

春季低温对小麦颖果发育的影响

为了探明春季低温（倒春寒）导致小麦减产的细胞学机理，以扬麦15为材料，在小麦幼穗处于雌雄蕊分化期至药隔期之间时，设置-3 ℃低温处理，通过树脂半薄切片对颖果不同发育时期的形态结构进行观察。结果表明：（1）在颖果发育早期，低温促进了颖果的长度生长，抑制了宽度生长；与对照相比，低温处理组小麦颖果发育进程缩短；（2）低温处理组颖果果皮发育早，中果皮降解速度快；（3）低温处理增加了胚乳淀粉体的积累量，降低了蛋白体的积累量，发育后期胚乳充实度显著低于对照组；（4）与对照相比，低温处理后颖果韧皮部面积和珠心突起传递细胞面积增大。以上结果表明，春季低温处理更有利于养分运输组织的发育，使得灌浆时间缩短，最终导致淀粉积累量增加及颖果早熟。     

环境与摄食对山东省近海鱼礁区不同体长许氏平鲉分布的影响

为研究环境与摄食因素对人工鱼礁区不同体长许氏平鲉分布的影响,采用2017—2018年山东省近岸3处鱼礁区环境和渔业资源的调查数据,利用变异系数CV均值将样本的体长分为10组,每组体长间隔为33 mm,并使用Bray-Curtis相似性指数比较不同海域许氏平鲉体长组成的相似性;运用去趋势对应分析(DCA)、典范对应分析(CCA)分析各环境要素对不同体长组许氏平鲉分布的影响;运用胃含物分析法分析许氏平鲉的食物组成。结果显示,西霞口与长岛鱼礁区样本体长组成相似性指数为70.66%,前三岛鱼礁区与西霞口鱼礁区、长岛鱼礁区的相似性指数较低,分别为54.94%和59.46%;大体长(299～365mm)许氏平鲉的分布与水深、水质指数(WQI)和化学需氧量(COD)相关性较大,喜好水深较深、营养丰富的水域;小体长(35～200 mm)许氏平鲉喜好水深较浅,水质好的水域。大体长(200～365 mm),高龄(2～3龄)的个体主要摄食鱼类、虾类和蟹类,优势饵料为鱼类(IRI为65.94%);小体长(35～200 mm),低龄(0～1龄)的个体主要摄食虾类和蟹类,优势饵料为虾类(IRI为45.69%)。研究表明,在浅水区域投放幼鱼保护型鱼礁,为幼鱼提供庇护所;将捕捞作业集中在深水区,减少对许氏平鲉小体长个体的兼捕,可以达到针对性增殖、保护许氏平鲉资源的目的。     

福瑞鲤选育家系不同养殖阶段的生长差异分析

为了进一步观察最佳线性无偏预测(best linear unbiased prediction,BLUP)家系选育方法在福瑞鲤(Cyprinus carpio)继代选育中的潜力,该研究测量了继续选育第2代家系群体不同养殖阶段的体质量和形态性状。结果表明,生长快速家系群福瑞鲤早期(4月龄)生长速度较慢,到后期则生长加快,其体质量增长表现出明显的优势。在体型方面,随着养殖时间的延长,福瑞鲤各选育家系群的体厚/体长增加,体高/体长降低,逐渐呈现其体型修长的特征;同时2个越冬期的成活率均达到了94%以上。结果表明通过BLUP家系选育对福瑞鲤长期选育是可行的。在此基础上,通过主成分分析发现,福瑞鲤生长性状第一主成分是体质量;对不同生长时期的体质量进行相关性分析,发现9月龄、14月龄、21月龄鱼的体质量与24月龄的相关系数均达到极显著水平(P0.01),分别为0.851、0.897和0.957。因此,在福瑞鲤继续选育过程中,进行早期个体选择值得尝试。     

Long-Term and Immediate Effects of Whole Body Vibration on Chronic Lameness in the Horse: A Pilot Study

The effects of whole body vibration (WBV) in horses with chronic lameness were evaluated in an experimental, single subject, repeated measure design. To assess the long-term effect of WBV, eight horses not previously exposed to WBV were subject to WBV, 30 minutes twice daily, five days a week, for 60 days in addition to their regular exercise routine. Lameness was assessed subjectively and objectively 30 days before the start, at the start and 30 and 60 days after the start of the treatment (WBV). The immediate effect of WBV was assessed in four horses accustomed to WBV, by comparing lameness before and within 30 minutes of a single 30-minute WBV session at four different time intervals. Change in lameness was sought using paired t tests on the kinematic data. A P-value of <.05 was considered statistically significant. Intraindividual change was sought using a subjective and objective scoring system. No statistically significant change in lameness was seen after 30 or 60 days of WBV, respectively, in the chronically lame horses not previously exposed to WBV. However, a trend toward improvement was observed after the first 30 days of WBV, but this improvement appeared to be lost during the second 30 days of WBV. Although a statistically significant worsening of front limb lameness was seen immediately after a single 30-minute WBV session in the chronically lame horses accustomed to WBV, this result was largely attributed to a very significant worsening of the front limb lameness in one horse within that group.     

Comparative study on dietary protein requirements for juvenile and pre‐adult gibel carp (Carassius auratus gibelio var. CAS III)

Two 8‐week growth trials were conducted in indoor recirculation system to evaluate the protein requirements for juvenile (3.70 ± 0.20 g) and pre‐adult (85.2 ± 0.70 g) gibel carp, Carassius auratus gibelio var. CAS III. Six isoenergetic diets were formulated for each trial using fish meal and casein as protein sources, and protein level was 250–450 g kg^?1 in Trial 1 and 200–450 g kg^?1 in Trial 2. With the increasing dietary protein, feeding rate (FR) and feed conversion ratio (FCR) significantly decreased (P < 0.05). Weight gain (WG) increased first and then reached a plateau in 330–450 g kg^?1 in Trial 1 (P > 0.05), while decreased after the maximum value in 350 g kg^?1 in Trial 2 (P < 0.05). Productive protein values (PPVs) were lower in 370–450 g kg^?1 in Trial 1 and 400–450 g kg^?1 in Trial 2 (P < 0.05). Increasing dietary protein level increased protein content and decreased lipid content in whole fish body and white muscle (P < 0.05). Apparent digestibility coefficient of dry matters (ADC_d) decreased, while apparent digestibility coefficient of protein (ADC_p) increased in 370–450 g kg^?1 in Trial 1 and 250–450 g kg^?1 in Trial 2 (P < 0.05). Trypsin activity significantly increased in 370–450 g kg^?1 in Trial 1 (P < 0.05) and was not affected in Trial 2 (P > 0.05). Hepatic alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities in both trials increased when dietary protein was above 400 g kg^?1 (P < 0.05). Based on quadratic regression of WG, it was estimated that dietary protein requirement for maximum growth was 414 g kg^?1 (digestible protein of 376 g kg^?1) and 365 g kg^?1 (digestible protein of 324 g kg^?1) for juvenile (3.70 g) and pre‐adult gibel carp (85.2 g).     

Removal of a metallic foreign body from the tongue of three horses

The objective of this case report is to describe the diagnostic and surgical techniques for removal of a metallic foreign body in the tongue of three adult horses. The three horses were presented for evaluation and treatment of dysphagia and marked hypersalivation of 3–5 days duration. Radiographs of the head revealed the presence of a metallic foreign body in the tongue of each horse. The foreign bodies could be precisely localised under general anaesthesia using palpation and lingual ultrasonography and/or lingual radiography in combination with a forceps as a marker. The foreign bodies were successfully removed using laparoscopic instruments creating minimal soft tissue trauma. The use of long (43 cm) small laparoscopic (5 mm) instruments enabled good visualisation of the surgical field, providing optimal conditions for successful minimally invasive surgical treatment of horses with foreign bodies in the tongue. The three horses made uneventful recoveries and 12 months after surgery were eating normally and could be ridden with a bit as per usual routine. It was concluded that using long laparoscopic instruments in combination with palpation, ultrasonography and/or radiography allowed removal of the foreign body creating minimal soft tissue trauma and allowing optimal conditions for a fast recovery.     

略阳乌鸡体重和产蛋数性状遗传参数估计

【目的】略阳乌鸡是陕西省特有的家禽品种,该品种具有体型大、肉质好、氨基酸含量丰富、对林地散养适应性强的优点,但也存在生长缓慢,产蛋性能差的不足。为此,在系统测定略阳乌鸡生产性能的基础上,开展对体重和产蛋性状遗传参数的估计,阐明遗传效应对上述性状的调控作用及性状间的遗传关系,期望为这些性状的选育奠定理论基础。【方法】对略阳乌鸡蛋用系一世代71个半同胞家系799只公鸡和804只母鸡6、10、14、20周龄和开产日龄体重进行测定,以个体为单位记录从开产到31、35和40周龄产蛋数,以四分位数±1.5倍四分位距为界删除异常值,更正性别记录错误。以性别为固定效应,育种值为随机效应用单变量动物模型估计各性状遗传力,用双变量动物模型估计性状间遗传相关,用逆伽玛分布指定育种值和残差项方差先验分布,用贝叶斯算法执行130 000次迭代,弃去前30 000次迭代结果,以100为间隔抽取1 000个估计值获得方差和协方差后验分布,计算各性状遗传力和性状间遗传相关。用R语言PerformanceAnalytics软件包chart.Correlation命令计算性状间表型相关。【结果】略阳乌鸡6、10、14、20周龄公鸡体重为（0.56±0.07）、（1.07±0.13）、（1.56±0.19）、（1.97±0.21）kg,母鸡体重为（0.47±0.06）、（0.86±0.12）、（1.18±0.16）、（1.48±0.19）kg,开产体重为（1.68±0.23）kg;31、35和40周产蛋数为（31.2±11.5）、（42.5±16.7）和（54.7±20.4）枚。体重遗传力随年龄逐渐减小,分别为0.74、0.76、0.63、0.54和0.52,置信区间在0.25—0.33之间。产蛋数遗传力为0.27、0.25和0.26,置信区间在0.35—0.42之间。10、14、20周龄体重间维持中等偏上（0.52—0.68）的遗传相关性,但6周龄体重（0.21—0.52）和开产体重（0.21—0.46）与各时间点体重遗传相关性较弱。体重间遗传相关系数置信区间在0.13—0.34之间。在3个时间点产蛋数间遗传相关系数趋近于1,置信区间在0.03—0.06之间。体重和产蛋数间遗传相关系数均不显著。在时间维度上,各体重性状间表型相关系数在0.43—0.90之间（P<0.001）,产蛋数性状间表型相关系数在0.79—0.94之间（P<0.001）。6—20周龄体重与产蛋数间维持了弱（0.023—0.15）正相关关系,但开产体重与产蛋数存在弱负相关关系（-0.17—-0.14）。【结论】首次估计了略阳乌鸡品种特异性的遗传参数,发现略阳乌鸡体重性状主要受遗传效应调控,而产蛋数性状受环境影响更大,阐明了早期与晚期性状间、体重与产蛋数间的遗传关系,为早期选种和多性状育种奠定了理论基础。这些结果建议在略阳乌鸡群体中对体重性状表型选择有望取得良好效果,但对产蛋数性状应建立纯系利用杂种优势;体重和产蛋数间不存在负遗传相关关系,可同时对两个性状选育提高。     

黑斑侧褶蛙变态前后身体大小的变化 及对植物血凝素的反应模式

为了解不同发育阶段黑斑侧褶蛙（Pelophylax nigromaculatus）身体大小和对植物血凝素（Phytohemagglutinin-P，PHA-P）溶液的反应，在室温为（25±2）℃条件下，戈斯纳37、38～39、40～41、42～43、44～45和46期蝌蚪被取样，测定了体重、体长、尾长、体全长和重长比，以及注射PHA-P溶液前（0 h）和注射后3，6，9和12 h被注射部位皮肤组织的增厚程度的变化。不同发育阶段蝌蚪的体重无显著差异（P>0.05），体长、尾长和体全长均随发育进程推进而缩短（P<0.05），但重长比在登陆前后明显增大（P<0.05）。登陆前（37～43期）蝌蚪对PHA-P的反应的峰值出现于注射后3 h（P<0.05），登陆后（44～45期和46期）出现于注射后6 h（P<0.05），但不同发育阶段的最大PHA-P反应无明显的组间差异（P>0.05）。黑斑侧褶蛙登陆后尾部萎缩，重长比明显增加，这些特征有利于提高其对陆生环境的适应性，但对PHA-P的反应的峰值被延迟，这可能是造成蝌蚪登陆后存活率低的主要原因之一。     

褐飞虱自噬相关基因NlATG4的表达与功能

ATG4是一种半胱氨酸蛋白酶,负责ATG8蛋白羧基末端的切割,在自噬体形成过程中发挥重要作用。本研究克隆得到褐飞虱ATG4基因（NlATG4）的cDNA全长序列（GenBank登录号:MF062502.1）。RT-qPCR分析结果表明,NlATG4基因在褐飞虱的若虫和成虫时期均有表达,1～2龄若虫的表达量最高,在其他发育阶段的表达量稍低。RNAi结果显示,在dsRNA注射后的第4 d,靶标基因NlATG4的表达量显著下降（仅为dsGFP对照组的22%）,同时,NlATG4的RNA干扰导致虫体ATP含量显著降低,仅为1.0 μmol/(L·mg蛋白^-1),为对照组的25%;在注射后的第6 d,dsNlATG4处理组的褐飞虱存活率出现显著降低,其脂肪体组织变得松散,大型脂滴（直径≥5.0 μm）数量增多,类酵母共生菌周围泡状结构的界限基本消失;在注射后的第8 d,dsNlATG4处理的褐飞虱的存活率下降为36.7%,比dsGFP对照组的存活率下降53.3%。本研究表明靶向NlATG4基因的RNA干扰会破坏褐飞虱脂肪体的结构完整性和类酵母共生菌的微环境,影响脂类物质代谢和ATP含量,并导致褐飞虱存活率降低。因此,NlATG4基因在褐飞虱正常生长发育中发挥重要作用,在褐飞虱防治中具有一定的潜力。