Exposure to ecotourism reduces survival and affects stress response in hoatzin chicks (Opisthocomus hoazin)

Ecotourism helps to protect many habitats, but may also have negative impacts on wildlife. We investigated effects of ecotourists on reproductive success of hoatzins (Opisthocomus hoazin) and on hormonal status of their chicks in Amazonian rainforest lakes by comparing birds from undisturbed and from tourist-exposed nests. Hatching success was similar in both groups but chick survival was much lower at tourist-exposed nests than at undisturbed nests. This effect was due to an increased mortality of juveniles prior to fledging whereas small nestlings seemed largely unaffected. Juveniles, but not nestlings, living at tourist-exposed sites had a lower body mass and showed a stronger hormonal response to experimental stress compared to individuals at undisturbed sites. These data suggest that juvenile hoatzins were susceptible to tourist-induced stress which in turn may be responsible for the lower survival. In contrast, adult hoatzins that were incubating had apparently habituated to tourist presence because their flush distances at tourist-exposed nests were 50% lower than at undisturbed sites. Our findings demonstrate that individuals in different life stages show different susceptibilities to tourism. We suggest that even just watching animals during breeding can threaten their survival, but a proper scientific management of off-limit zones and area-specific guidelines for wildlife observation could reduce harmful effects.     

花生子叶不定芽的诱导和组织细胞学观察

以MS＋6.79μmol/L2,4-D＋22.19μmol/L6-BA为诱导培养基,以花生成熟种子子叶为外植体,诱导出大量丛生芽和少量体细胞胚;组织细胞学观察发现,子叶外植体不经过愈伤组织,直接诱导分化出丛生芽和体细胞胚,属于直接发生途径;并且子叶丛生芽和体细胞胚起源于外植体表皮或皮层细胞,为外起源方式。     

促进动物医学专业学生临床诊断实践能力提高的探讨

兽医临床诊断实践能力是动物医学专业学生得以发展和创新的坚实基础。从兽医临床诊断实践教学的角度,对促进动物医学专业学生临床诊断实践能力提高的策略进行了探讨。     

犬用益生菌研究进展

随着宠物饲养观念的改变,犬用益生菌的市场也在不断扩大。在犬的临床诊疗中,益生菌常用于调节肠道菌群、增强免疫力、提高幼犬生长性能、调节炎性反应、预防草酸钙结石和增强抗氧化性能等方面。就以上方面的应用进行阐述,分析犬用益生菌可能的作用机理和目前存在的问题,并探讨其未来发展前景和方向,以期为犬用益生菌的进一步合理开发和有效应用提供参考。     

中药复方颗粒剂对断奶腹泻仔猪小肠黏膜超微结构的影响

为研究中药颗粒剂对断奶腹泻仔猪小肠黏膜超微结构的影响,选择（28±1）d、体重10.04 kg左右的杜长大三元杂种断奶腹泻仔猪18头,随机分为抗生素治疗组和中药复方颗粒剂治疗组,每组3个重复,每个重复3头猪。两组分别于用药后14 d每组随机抽取3头猪颈动脉放血处死,腹腔解剖观察病理变化,无菌采集小肠黏膜进行细胞学观察。结果显示,中药复方颗粒剂治疗组小肠黏膜除有少量出血外,未发现明显病理变化。抗生素治疗组小肠黏膜脱落,有广泛充血、出血;黏膜上皮细胞变性坏死;嗜酸性粒细胞浸润,有大量以淋巴细胞（LELs）、杯状细胞（GSs）为主的炎性细胞浸润;微绒毛排列紊乱,脱落;细胞受损严重,线粒体等细胞器结构异常。表明抗生素治疗仔猪腹泻造成小肠黏膜显著的病理变化和功能障碍,而中药复方颗粒剂治疗有利于仔猪小肠黏膜结构的修复。     

绵羊痘的诊断

绵羊痘是由绵羊痘病毒引起绵羊的疾病,其特征为发热、全身皮肤痘疹,内脏(特别是肺脏)黏膜结节,是危害养羊业最为严重的传染病之一。该病经常引起绵羊的大批感染或死亡,病死率可达50%以上,羔羊可达100%,不仅给养羊业带来巨大的经济损失,还严重阻碍了养羊业的发展。文章针对2011年1月份新疆某地区部分养羊户饲养的卡拉库尔羊发生的羊痘疫情进行了流行病学调查、临床症状、病理变化观察和实验室诊断,结果确诊为绵羊痘。     

Predictive equations of maintenance energy requirement for healthy and chronically ill adult dogs

Maintenance energy requirement (MER) is the energy amount necessary for dogs to maintain their weight and body condition. Some factors can influence the MER, such as gender, age, neutering status and also diseases. The present retrospective study aimed to evaluate MER of adult dogs with several diseases and compare with the MER of healthy adult dogs, observing the influence of parameters such as body condition score (BCS), neutering status, gender, age, diagnosis and type of food on MER of these dogs. A total of 165 adult dogs with weight changes of ≤5% were included and divided in groups according to diagnosis. Mean MER for healthy dogs was 86.09 kcal/BW^0.75, which differed from NRC and FEDIAF recommendations for inactive adult dogs (p = .047). Lowest MERs were of the endocrinopathies (78.52 ± 19.32 kcal/BW^0.75), orthopaedic diseases (59.71 ± 19.30 kcal/BW^0.75) and neurologic diseases (78.83 ± 32.66 kcal/BW^0.75) groups. Gastrointestinal diseases (99.59 ± 20.36 kcal/BW^0.75), orthopaedic diseases (59.71 ± 19.30 kcal/BW^0.75) and neoplasia (95.61 ± 21.02 kcal/BW^0.75) groups were the only groups that differed from the mean MER of healthy adult dogs. Regarding BCS, for each increasing point in a 9-point scale, there was a decrease of 9.8 kcal/BW^0.75 on MER, independent of diagnosis (p < .0001; r² = .55). There was no difference regarding breed size gender and age, but neutered dogs presented lower MER (p = .031). Based on data obtained from the present study, it can be concluded that it is necessary to consider BCS, age, neutering status and diagnosis when calculating MER, both in healthy dogs and chronically ill dogs.     

湘西自治州烟叶品质影响因子分析

[目的]分析烟叶品质及其影响因子,以有效利用影响因子来提高烟叶品质。[方法]利用湘西自治州7个县20个乡镇烤烟种植区的烟叶样品资料和相应的区域自动气象观测站资料,分析影响烟叶品质的生态因子。[结果]烤烟的大田平均气温对烤烟的品质指数、感官质量指数影响较大;成熟期日最高温度t〉35℃的天数和海拔高度也是影响烟叶品质指数的主要因子;烤烟成熟期的平均气温对烟叶的化学成分影响不明显。[结论]该研究可为湘西州烟叶生产、烤烟种植布局和特色优质烟叶开发提供有意义的指导。     

长江刀鲚性腺的细胞学观察

在长江南通如皋江段和安徽安庆江段分两个时期野外采集刀鲚样本，通过对其性腺发育的观察发现：长江刀鲚种群无论是从体长还是体重方面都呈下降趋势，越靠近上游的个体越小。刀鲚性腺成熟程度与体长、体重等生物学指标没有必然联系，与所处长江江段关系不大，而与洄游时间及水温度密切相关，4月洄游群体性腺发育程度分别为Ⅱ、Ⅲ期，6月上旬洄游群体的性腺发育程度为Ⅳ、Ⅴ期。越晚洄游进入长江的刀鲚，其产卵场可能越处于下游，越接近长江口。     

Tiludronate infusion in the treatment of bone spavin: A double blind placebo‐controlled trial

Reasons for performing study: Tiludronate regulates bone remodelling through a decrease of the resorptive process and should therefore ameliorate the remodelling processes active in osteoarthritis of the distal tarsal joints (‘bone spavin’) and alleviate pain associated with abnormal bone lysis. Objective: To confirm the efficacy of tiludronate, administered as a single infusion at a dose of 1 mg/kg bwt, in the treatment of bone spavin in the horse. Methods: A double blind placebo controlled trial on 108 clinical cases of bone spavin was undertaken. The lameness score of the lamest limb was assessed following distal tarsal analgesia of the contralateral limb and followed‐up using the same procedure throughout the study. Bone spavin in the lamest limb was confirmed by distal tarsal analgesia and radiography. Horses were treated at Day 0 and reassessed 60 days later after controlled exercise. A second nonblinded treatment was given to unresponsive horses and all horses were re‐examined at Day 120. Exercise levels were recorded at each examination. Results: Eighty‐seven horses completed the trial as per the protocol. The tiludronate horses were significantly less lame than the placebo horses (P = 0.0318). Horses treated at Day 60 with tiludronate showed further improvement in lameness at Day 120 (P = 0.0096 and P = 0.0034 for horses treated with tiludronate and placebo at Day 0, respectively). The only significant difference in radiographic findings between tiludronate and placebo was for presence of periarticular osteophytes (P = 0.006). Conclusions: Tiludronate treatment is proven to be effective in bone spavin in horses in association with a controlled exercise programme. Clinical relevance: Tiludronate in combination with controlled exercise offers an alternate medical treatment for bone spavin.