Evaluation of the present breeding programme against copper toxicosis in Danish Bedlington terriers

A breeding programme to eradicate copper toxicosis in Danish Bedlington terriers has been established based on a DNA marker test. Genotyping of both parents is compulsory and after 1 January 2000, only homozygous non-carriers are used for breeding. In this study, two groups of Bedlington terriers were genotyped at 18 microsatellite loci. One group represented the original population of Bedlington terriers before introducing the breeding programme (n = 23); the other represented a group of homozygous non-carriers (n = 24) available for breeding after year 2000. Allele numbers, allele frequencies, observed heterozygosities (Ho), expected heterozygosities (He), locus-specific coefficients of inbreeding (Fl) and Nei's genetic distance (D) was calculated. Individual coefficients of inbreeding (Fi) were calculated from the pedigrees and an assignment test was performed. Four rare alleles were lost in the group of homozygous non-carriers. No significant differences were observed between the mean values of allele numbers, Ho, He, Fl and Fi of the two populations of dogs. Nei's genetic distance between the two populations was 0.06 and 88% of the homozygous non-carriers were assigned correctly in the assignment test. The overall diversity of the breed was low (Ho = 0.41) and the breeders were advised to include the heterozygous carriers again.     

Exclusion of the PDE6A gene for generalised progressive retinal atrophy in 11 breeds of dog

The cyclic guanosine monophosphate specific phosphodiesterase (cGMP-specific PDE) is a key enzyme in the phototransduction cascade of the vertebrate retina. This enzyme consists of two catalytic alpha and beta subunits, two identical inhibitory gamma subunits as well as a delta subunit. Mutations in PDE6A and the PDE6B genes lead to autosomal recessive (ar) forms of retinitis pigmentosa (RP) in human and to the homologous disease in dogs, designated generalised progressive retinal atrophy (gPRA). We investigated the PDE6A gene in 13 gPRA-affected dog breeds including healthy animals, obligate gPRA carriers and gPRA-affected dogs. In the coding region of PDE6A only a rare sequence variation (G103A; Asp35Asn) was found in exon 1 of two healthy Tibet Terriers and one affected Cocker Spaniel. Using single-stranded conformation polymorphism (SSCP) analyses we detected several sequence variations in eight of the PDE6A introns in different investigated breeds. Most informative for excluding the PDE6A gene as a cause for gPRA was a polymorphic microsatellite ((GT)10CG(GT)2CG(GT)12) in intron 14 and four sequence variations in intron 18 for almost all breeds investigated. The sequence variations of PDE6A did not segregate together with gPRA in 11 breeds. Since diseased animals were heterozygous for the polymorphisms, the PDE6A gene is unlikely to harbour the critical mutation causing gPRA in the following breeds: Chesapeake Bay Retriever. Entlebucher Sennenhund, Labrador Retriever. Tibet Mastiff, Dachshund (long- and wire-haired), Tibetan Terrier, Miniature Poodle. Australian Cattle Dog, Cocker Spaniel, Saarloos/Wolfshound, Sloughi.     

Further evidence that deltamethrin-impregnated collars protect domestic dogs from sandfly bites

In many foci of zoonotic visceral leishmaniasis (ZVL), domestic dogs are important reservoir hosts of the causative Leishmania parasites transmitted by phlebotomine sandflies (Diptera: Psychodidae). We tested the protective value of impregnated dog collars (20 g plastic containing deltamethrin 800 mg ai) against Phlebotomus papatasi (Scopoli) sandflies in Iran. For each assay, the dog was sedated and caged in a net with 70-100 wild-caught sandflies overnight (23.30-06.30 hours). Dogs wearing the collars were bitten by approximately 80% fewer sandflies than before collars were fitted, i.e. 51% vs. 11% of hungry female flies exposed. Sandfly mortality rates following 20 h exposure to dogs with collars (18%) or without collars (17%) were not significantly different. Effects of collars were tested when dogs had been wearing them for 8 days. A previous trial against the sandfly P. perniciosus Newstead in France, using smaller dogs, showed that effects of such collars were not fully realized until they had been worn for 2 weeks or more; they remained effective for at least 8 months and killed significant proportions of the sandflies exposed. Present results with P. papatasi, confirming that this simple device provides effective protection against sandflies, are considered sufficiently encouraging to justify a community-wide field trial of deltamethrin-impregnated dog collars against ZVL vector sandflies in Iran.     

Distinguishing kinds of prior dominance and subordination experiences in males of green swordtail fish (Xiphophorus helleri)

In experiments, there are usually two general ways of obtaining dominants and subordinates to test for the effect of recent experience upon ulterior behavior and dominance. One is to ‘impose’ such an experience on the contestants by a priori deciding which individual of the pair will become the dominant and which will become the subordinate through the use of rigged contests. The second technique is to let contestants ‘self-select’ the winner and loser by waiting for the spontaneous outcome of dyadic encounters between two usually well matched opponents. These two techniques of obtaining dominants and subordinates probably represent extreme cases on a single continuum of investment made by animals to settle dominance. To test this, we compared dominants and subordinates obtained from these two techniques in Xiphophorus fish males. It was found that pairs obtained through rigged contest (R) were much more aggressive in subsequent encounters than pairs in which the dominant and subordinate could self-select (S). They recuperated more rapidly from handling, initiated contact earlier, took more time to assess each other, and fought for a longer period of time. Prior-winners and prior-losers of the R condition more frequently relied on aggressive behavior during contest than that of the S condition. As a consequence, prior-winners and prior-losers of the R condition won equally the subsequent contest. On the contrary, prior-winners of the S condition defeated their prior-loser opponent in a majority of cases. These results can be tentatively explained by the following principle, winning or losing against a well matched opponent would leave more ‘experience’ than winning over a much weaker opponent, or losing to a much stronger one. This reinforces the hypothesis that prior-experiences are not qualitative states but come in various degrees.     

Factors affecting the outcome of territorial contests between hatchery and naturally reared coho salmon parr in the laboratory

In aquarium experiments using coho salmon as a model species, prior residents dominated intruders of the same size but intruders with a 6% length advantage were equally matched against prior residents. Prior winning experience (distinct from individual recognition) also strongly influenced competitive success and overcame a prior residence effect. Coho salmon reared in a hatchery dominated size-matched fish from the same parental population reared in a stream. Hatchery-reared salmon also dominated naturally spawned salmon, even when the wild salmon were prior residents. Thus the combined effects of greater size and rearing experience of hatchery-produced salmon were sufficient to overcome a wild salmon's advantage of prior residence. Efforts to rehabilitate salmonid populations must consider such behavioural interactions if displacement of wild fish is to be prevented.     

Early behavioral development and temperamental traits in mother- vs peer-reared rhesus monkeys

Behavioral characteristics (“traits”) of 24 mother-reared and 24 nursery/peer-reared rhesus monkey infants were assessed via rating scales from the third through the seventh month of life while housed with their rearing partners, and from months 8–10 after all animals had been placed in novel peer groups. The animals were also tested at 8 months of age on the Bayley Scales of Infant Development adapted for nonhuman primates. During the early period effects noted were primarily developmental. Peer-reared animals were rated as increasingly less cautious and more attentive to the outside environment over time, while mother-reared infants declined in ratings of dependence on their mothers. All animals were rated as increasingly active and excitable, and less fearful, over time. For the period of months 8–10, peer-reared animals showed higher confidence ratings in month 10, and all animals showed a decline in attachment to cagemates. Mother-reared animals showed more hostility to the examiner during Bayley testing, whereas peer-reared animals showed more fear. Sex effects included greater ratings for independence from mothers, greater activity over both the early and later periods, greater excitability, greater attentiveness to the extra-cage environment, less cautiousness, and better performance on one Bayley problem for females.     

复杂性眼外伤患者玻璃体切割围手术期护理体会

目的:玻璃体切割术是眼科手术中比较复杂精细显手术,主要应用于治疗眼外伤导致的玻璃体出血,玻璃体浑浊,复杂性视网膜脱离以及增殖性玻璃体视网膜病变。本文主要探讨玻璃体切割术治疗复杂性眼外伤患者的围手术期护理的临床效应。方法:总结作者所在科室多年来护理眼外伤患者的临床经验,对2013年3月至2013年7月入院的75例(75只眼)复杂性眼外伤患者进行悉心的术前心理护理,完善的用药指导,充分的术前准备,术后特殊卧位的指导,预防并发症的护理及出院指导。结果:术后视力提高57例(76.0%),视力不变13(17.3%)例,视力下降5例(6.7%),28例眼内异物患者均经手术顺利取出异物。相关手术并发症经医护人员的对症治疗后均得到有效控制。患者术后满意度达98%以上,医生满意度达100%。结论:复杂性眼外伤患者玻璃体切割手术围手术期进行全方位的护理服务,对促进病人康复起到至关重要的作用。     

海水浸泡开放性犬颅脑爆震伤影像学模型的建立

目的:建立海水浸泡开放性犬颅脑爆震伤影像学模型。方法:本实验采用新型球形爆炸源。狗颅中线向左(右)1cm,眶上缘向上1cm交界处为爆炸中心位置。爆炸距离(爆炸源最低点距爆炸点的距离)分别为3mm,3.5mm,4mm。比较各个距离的爆炸效果,选出最适的爆炸距离。在动物最适爆炸距离致伤后用吊瓶装满海水(秋季福建沿海距岸边200米深部海水),用皮管固定于伤口空洞中,使受伤脑组织始终浸泡于海水环境中。分别于3h,5h,8h行颅脑CT检查。观察海水浸泡开放性颅脑爆震伤的CT动态变化。结果:爆炸距离3.5mm为最适爆炸距离,此距离爆炸致伤后犬存活率高,能够炸开颅骨,使脑组织暴露,海水浸泡爆震伤口8小时,脑水肿逐渐出现。结论:本实验所建立的动物模型可模拟真实海战下冲击波致伤,且重复性和稳定性好,易操作,适用于海战情况下颅脑爆震伤的实验研究。