Canine Dimorphism and Interspecific Canine Form in Cebus

I investigated canine dimorphism and interspecific canine form in adult specimens from 4 capuchin species (Cebus albifrons, C. apella, C. capucinus, and C. olivaceus). I used various univariate and multivariate statistics, which are based on 6 variables, to test several hypotheses that are based upon the finding that canine dimorphism is strongly associated with intermale competition in platyrrhines (Kay et al., 1988), Greenfield (1992a), Plavcan and van Schaik (1992, 1994). Results from the indices of canine dimorphism and the unpaired t-tests corroborate the prediction that males of each species possess significantly larger canines than those of females. Large male canines are especially prominent in 2 variables, maxillary and mandibular canine height. Greene's t-test (1989) does not support the prediction that Cebus apella and C. olivaceus possess a larger degree of canine dimorphism relative to C. albifrons and C. capucinus. No interspecific differences in degree of canine dimorphism are indicated by this test. Results of the discriminant function analyses (DFA) do not find that Cebus apella and C. olivaceus possess different canine form relative to C. albifrons and C. capucinus as predicted. However, Cebus apella is differentiated from the untufted capuchins (C. albifrons, C. capucinus, and C. olivaceus) by the DFA. I suggest that intermale competition is the primary selective force underlying the observed morphological patterns; however, it does not explain all the variation associated with canine dimorphism in Cebus.     

Canine pyometra

Pyometra, literally meaning pus in the uterus, is a common disease entity of intact bitches. Similar conditions occur, including hydrometra and mucometra [De Bosschere H, Ducatelle R, Vermeirsch H, Van Den Broeck W, Coryn M. Cystic endometrial hyperplasia-pyometra complex in the bitch: should the two entities be disconnected? Theriogenology 2001;55:1509-19]. The exact etiology is unknown; however the repeated and prolonged response to estrogen followed by long intervals of progesterone dominance in the intact bitch leads to hormonally mediated changes in the endometrium. The endometrium changes when impacted by bacterial infiltration; changes in endometrial steroid receptors can result in the clinical syndrome described as pyometra. This paper will describe the signalment, risk factors, prevalence, proposed etiologic events, and both medical and surgical therapies. In addition, the prognosis for successful outcome and effects on future reproduction will also be described.     

Canine dimorphism

Canine dimorphism in many primates is exaggerated, with males possessing enormous, sharp canines that project far beyond the occlusal plane of the other teeth and females having smaller, less projecting canines. Ever since Darwin,¹ canine dimorphism generally has been attributed to sexual selection. However, recent analyses suggest that the evolution of canine dimorphism is complex and that the sexual selection hypothesis is only part of the story.     

犬布鲁氏菌病

目前,犬布鲁氏菌病在全球多个国家和地区都有发生,而且发病数量逐年上升,由犬布鲁氏菌病感染人的病例报道也日益增多。因此,犬布鲁氏菌病的控制和根除对人类健康和公共卫生安全具有重要的意义。据报道,我国多个省份存在犬布鲁氏菌病,而且感染和发病率有上升的趋势。由于我国养犬数量巨大,犬与人类接触密切,病犬作为人类布鲁氏菌病的传染源不容忽视。犬布鲁氏菌病的研究起步较晚,流行病学资料欠完善,公共卫生学意义有待阐明,诊断、免疫预防等诸多问题还没完全解决,加强犬布鲁氏菌病的研究和防控应引起足够的重视。本文就犬布鲁氏菌病的病原学、流行病学、病理学、临床症状、诊断、治疗、预防及公共卫生安全等分别做一阐述。     

Canine fibrinogen glycopeptides

Canine fibrinogen was digested by a complex of proteases from Streptomyces griseus. The degradation products were purified by gel-filtration, DEAE-cellulose chromatography and electrophoresis, resulting in nine glycopeptides, eight of which contained aspartic acid and one--serine. The other amino acids were found only in trace amounts. The glycopeptides were shown to contain hexoamines, mannose, galactose and sialic acid. The oligosaccharide chains form a sequence of structurally similar variants. The individual microheterogeneity of canine fibrinogen with respect to carbohydrate chains was detected. A comparison of the carbohydrate composition of fibrinogen and glycopeptides suggests the presence of four carbohydrate chains in the protein molecule.     

Canine epilepsy genetics

There has been much interest in utilizing the dog as a genetic model for common human diseases. Both dogs and humans suffer from naturally occurring epilepsies that share many clinical characteristics. Investigations of inherited human epilepsies have led to the discovery of several mutated genes involved in this disease; however, the vast majority of human epilepsies remain unexplained. Mouse models of epilepsy exist, including single-gene spontaneous and knockout models, but, similar to humans, other, polygenic models have been more difficult to discern. This appears to also be the case in canine epilepsy genetics. There are two forms of canine epilepsies for which gene mutations have been described to date: the progressive myoclonic epilepsies (PMEs) and idiopathic epilepsy (IE). Gene discovery in the PMEs has been more successful, with eight known genes; six of these are orthologous to corresponding human disorders, while two are novel genes that can now be used as candidates for human studies. Only one IE gene has been described in dogs, an LGI2 mutation in Lagotto Romagnolos with a focal, juvenile remitting epilepsy. This gene is also a novel candidate for human remitting childhood epilepsy studies. The majority of studies of dog breeds with IE, however, have either failed to identify any genes or loci of interest, or, as in complex mouse and human IEs, have identified multiple QTLs. There is still tremendous promise in the ongoing canine epilepsy studies, but if canine IEs prove to be as genetically complex as human and murine IEs, then deciphering the bases of these canine epilepsies will continue to be challenging.     

Continuous-Flow Ultracentrifugation of Canine Distemper Virus and Infectious Canine Hepatitis Virus

The use of a Spinco L-4 zonal centrifuge with the B-XVI continuous-flow rotor for the purification of canine distemper and infectious canine hepatitis viruses is described. Up to 68 liters of virus was processed at one time. Infectious canine hepatitis virus was found to band at 39% sucrose and canine distemper virus banded between 32 and 48% sucrose. The virus was concentrated 10-fold, and the purity of the virus, as measured by protein concentration, was increased by 99%.