Scoring tail damage in pigs: an evaluation based on recordings at Swedish slaughterhouses

Background

There is increasing interest in recording tail damage in pigs at slaughter to identify problem farms for advisory purposes, but also for benchmarking within and between countries as part of systematic monitoring of animal welfare. However, it is difficult to draw conclusions when comparing prevalence’s between studies and countries partly due to differences in management (e.g. differences in tail docking and enrichment routines) and partly due to differences in the definition of tail damage.

Methods

Tail damage and tail length was recorded for 15,068 pigs slaughtered during three and four consecutive days at two slaughterhouses in Sweden. Tail damage was visually scored according to a 6-point scale and tail length was both visually scored according to a 5-point scale and recorded as tail length in centimetres for pigs with injured or shortened tails.

Results

The total prevalence of injury or shortening of the tail was 7.0% and 7.2% in slaughterhouse A and B, respectively. When only considering pigs with half or less of the tail left, these percentages were 1.5% and 1.9%, which is in line with the prevalence estimated from the routine recordings at slaughter in Sweden. A higher percentage of males had injured and/or shortened tails, and males had more severely bitten tails than females.

Conclusions

While the current method to record tail damage in Sweden was found to be reliable as a method to identify problem farms, it clearly underestimates the actual prevalence of tail damage. For monitoring and benchmarking purposes, both in Sweden and internationally, we propose that a three graded scale including both old and new tail damage would be more appropriate. The scale consists of one class for no tail damage, one for mild tail damage (injured or shortened tail with more than half of the tail remaining) and one for severe tail damage (half or less of the tail remaining).     

基于激振理论的玉米多棱摘穗辊设计与试验

针对当前纵卧辊式玉米收获机作业存在籽粒啃伤严重和落粒损失大的问题,以激振理论为指导,以玉米果穗与茎秆分离为条件,建立了适于玉米机械化收获的玉米激振摘穗理论模型;以该激振摘穗模型为指导,构建并优化了适于玉米激振运动的摘穗辊外形结构和配置方式,开发了相应的激振摘穗试验台;采用Box-Behnken试验设计方法,研究了激振摘穗辊棱边数、振幅、摘穗辊转速对果穗摘穗过程籽粒破损率和落粒损失率的影响规律,建立了试验因素与考察指标之间的回归方程,并生成了相应的响应曲面。结果表明,激振摘穗装置中棱边数、振幅和摘穗辊转速对收获过程果穗籽粒破损率和落粒损失率有显著的影响。以非线性规划理论为指导,确定了最佳组合为摘穗辊转速950 r/min、棱边数8、振幅0. 75 cm,在该条件下进行了试验验证,得出平均籽粒破损率为0. 124%,平均落粒损失率为0. 228%,均低于国家玉米收获机械技术标准要求。     

Crib‐biting in US horses: Breed predispositions and owner perceptions of aetiology

Reasons for performing study: Crib‐biting is an equine stereotypy that may result in diseases such as colic. Certain breeds and management factors have been associated. Objectives: To determine: breed prevalence of crib‐biting in US horses; the likelihood that one horse learns to crib‐bite from another; and owner perceptions of causal factors. Methods: An initial postal survey queried the number and breed of crib‐biting horses and if a horse began after being exposed to a horse with this habit. In a follow‐up survey, a volunteer subset of owners was asked the number of affected and nonaffected horses of each breed and the extent of conspecific contact. The likelihood of crib‐biting given breed and extent of contact was quantified using odds ratio (OR) and significance of the association was assessed using the Chi‐squared test. Results: Overall prevalence was 4.4%. Thoroughbreds were the breed most affected (13.3%). Approximately half of owners believed environmental factors predominantly cause the condition (54.4%) and crib‐biting is learned by observation (48.8%). However, only 1.0% of horses became affected after being exposed to a crib‐biter. The majority (86%) of horses was turned out in the same pasture with other horses and extent of contact with conspecifics was not statistically related to risk. Conclusion: This is the first study to report breed prevalence for crib‐biting in US horses. Thoroughbreds were the breed more likely to be affected. More owners believed either environmental conditions were a predominant cause or a combination of genetic and environmental factors contributes to the behaviour. Only a small number of horses reportedly began to crib‐bite after being exposed to an affected individual, but approximately half of owners considered it to be a learned behaviour; most owners did not isolate affected horses. Potential relevance: Genetic predisposition, not just intensive management conditions and surroundings, may be a factor in the high crib‐biting prevalence in some breeds, and warrants further investigation. Little evidence exists to suggest horses learn the behaviour from other horses, and isolation may cause unnecessary stress.     

基于线粒体COⅠ基因序列的吸血蠓近似种鉴定

为了快速、准确地鉴别吸血蠓近似种,弥补传统形态学鉴定方法在种类鉴定中存在的操作繁琐、难度大等不足,提出了基于线粒体CO Ⅰ基因序列的吸血蠓近似种鉴定方法。以二囊亚属中的黑色库蠓(Culicoides pelius)、无害库蠓(Culicoides innoxius)、白带库蠓(Culicoides albifascia)、不显库蠓(Culicoides obsoletus)、东方库蠓(Culicoides orientalis)、苏格兰库蠓(Culicoides scoticus)和琉球库蠓(Culicoides actoni)等7种库蠓近似种的部分线粒体CO Ⅰ基因序列作为分析对象,基于Kimura 2-parameter模型分析遗传距离,同时应用MEGA 6.0软件以荒川库蠓(Culicoides arakawai)为外群构建系统发育树(邻接法和最大似然法)。经过Clustal X序列比对及人工校对、编辑后, 7种吸血蠓CO Ⅰ基因长度为494 bp,遗传距离在种内和种间具显著差异(P<0.05),系统发育树中不同库蠓种类各自构成单系(群),同种类不同地理种群聚为一支。本研究初步证实了线粒体CO Ⅰ基因序列可用于吸血蠓近似种的分子鉴定。     

异物特征和断尾处理对断奶仔猪啃咬行为及其生产性能的影响

本文通过在猪栏内添加不同物理特征异物和断尾处理，对断奶仔猪的啃咬行为及其生产性能的影响进行了研究。试验中选择35～40日龄大白猪及长白猪断奶仔猪各6窝，从每窝选出健康均匀仔猪6头，转群后放入一栏，公母各占一半。其中两个品种各有2窝在出生后进行了断尾。试验分三个处理组T1，断尾组；T2，异物组一，在猪栏内放置篮球；T3，异物组二，在猪栏栅栏近地面处拴系三角皮带。每个试验组包括两个品种各两窝仔猪。试验使用摄像机，采取即时性观察方法进行观察。记录每日的采食量和仔猪试验前后的体重以计算日增重和饲料效率。试验结果表明，在猪栏内放置异物增加仔猪对添加异物进行探求和啃咬的时间。异物在栏内的位置不同对断奶仔猪咬尾行为、咬耳行为、咬蹄行为和啃栏行为等行为的影响不同。断尾也可以避免咬尾行为的发生，且有利于日增重和饲料效率的提高。     

异物特征和断尾处理对断奶仔猪啃咬行为及其生产性能的影响

本文通过在猪栏内添加不同物理特征异物和断尾处理 ,对断奶仔猪的啃咬行为及其生产性能的影响进行了研究。试验中选择 35～ 40日龄大白猪及长白猪断奶仔猪各 6窝 ,从每窝选出健康均匀仔猪 6头 ,转群后放入一栏 ,公母各占一半。其中两个品种各有 2窝在出生后进行了断尾。试验分三个处理组 :T1 ,断尾组 ;T2 ,异物组一 ,在猪栏内放置篮球 ;T3,异物组二 ,在猪栏栅栏近地面处拴系三角皮带。每个试验组包括两个品种各两窝仔猪。试验使用摄像机 ,采取即时性观察方法进行观察。记录每日的采食量和仔猪试验前后的体重以计算日增重和饲料效率。试验结果表明 ,在猪栏内放置异物增加仔猪对添加异物进行探求和啃咬的时间。异物在栏内的位置不同对断奶仔猪咬尾行为、咬耳行为、咬蹄行为和啃栏行为等行为的影响不同。断尾也可以避免咬尾行为的发生 ,且有利于日增重和饲料效率的提高。     

Gradients in fracture force and grazing resistance across canopy layers in seven tropical grass species

In reproductive swards, stems can act as a barrier that affects the grazing behaviour of ruminant livestock. The barrier effect of stems is closely associated with both the force required to fracture the stems and the density of these stems (in combination, these make up grazing resistance), and these factors need to be considered when making predictions about the forage intake of ruminants grazing reproductive pastures. Differences in grazing resistance between sward canopy layers of different grass species are thought to affect bite dimensions, but data are scarce. In this study, we assessed the grazing resistance for three canopy layers of seven tropical grass species. Species differed significantly in grazing resistance for every canopy layer, with a general ranking order for grazing resistance, in ascending order: Cenchrus ciliaris (‘American' buffel), Digitaria milanjiana (‘Jarra’ finger grass), Setaria surgens (annual pigeon grass), Setaria sphacelata (‘Narok’ setaria), Dichanthium sericeum (Queensland bluegrass), Chloris gayana (‘Callide’ Rhodes grass). In the top canopy layer, grazing resistance did not appear to create a barrier for any of the species, but in the bottom canopy layer, it did for all species. Species also differed in the relative contribution of fracture force and density to grazing resistance. The results highlight the importance of managing the grazing systems to minimize the barrier effect of the stems, which can be done by controlling the phenological stage of the pasture and the grass species and animal size used in the system.     

Influence of feed type and its effect on repressing wool‐biting behavior in housed sheep

Sheep sometimes develop an abnormal behavior termed as wool‐biting when kept in an indoor system; however, little is known about this behavior. As the provided feed type may affect the foraging behavior and repress abnormal behavior in animals, we tested the effect of feed type on repressing wool‐biting behavior in this study. We used hay prepared in three forms, that is hay bales, rolls and cubes. The wool‐biting frequency associated with hay bales was significantly higher than that associated with rolls (P < 0.05) and cubes (P < 0.05); however, there was no significant difference between rolls and cubes. For hay rolls, wool‐biting significantly decreased after feeding (P < 0.05), suggesting that rolls may provide sheep with appropriate oral stimulation; thus, decreasing the post‐feeding oral abnormal behavior. An individual difference of wool‐biting behavior between sheep was also detected, and an unexpected bed‐eating behavior was found in the hay cube treatment. We suggest that sheep performing movements that are similar to their natural foraging behavior while grazing would repress wool‐biting behavior, which happened in hay roll and hay cube treatments. Considering sanitation and animal welfare, providing sheep with hay rolls may provide an easier method to control wool‐biting behavior in housed sheep.     

Morphology of the leather defect light flecks and spots.

The skin histology and the scanning electron microscope morphology of the hide defect light flecks and spots after tanning were studied in 11 steers infested with biting lice (Damalinia bovis). Nine steers from herds free of lice were used as controls. Skin biopsies from 6 of the animals in the lice infested group showed mild to moderate hyperkeratosis and moderate perivascular to diffuse dermatitis with infiltration of mainly mononuclear cells and some eosinophilic granulocytes. The steers were slaughtered at an age of 18 to 23 months. Light flecks and spots occurred on all examined hides from the infested group after tanning. No examined hides from the control group demonstrated similar damage. Both light microscopic examination of sections of tanned hide with light flecks and spots and scanning electron microscopy of the same defects showed superficial grain loss and craters with a irregular fibre base encircled by smooth and intact grain. The association between louse infestation at an early age and damage of hides following slaughter 6 to 15 months later, suggested that louse infestations lead to a prolonged or lifelong weakening in the dermis. This weakening may cause superficial grain loss during the tanning process.     

麦红吸浆虫保幼激素含量测定

用气相色谱法对麦红吸浆虫Sitodiplosis mosellna(Gehin)成虫、麦穗幼虫、秋季滞育幼虫、冬季滞育幼虫和翌年春季活动幼虫保幼激素滴度进行了检测。结果显示,在麦红吸浆虫成虫和幼虫的不同阶段,都可检测到保幼激素Ⅲ的存在。比较而言,成虫保幼激素Ⅲ的滴度高于麦穗幼虫和秋季滞育幼虫,但明显低于冬季滞育幼虫和翌年出土幼虫。