Idiopathic detrusor-urethral dyssynergia in dogs: a retrospective analysis of 22 cases

Results of a retrospective study of 22 dogs with signs of dysuria and/or stranguria in which a diagnosis of idiopathic detrusorurethral dyssynergia was made are presented. The diagnosis was based on the exclusion of detectable pathological conditions which could also cause urine outflow obstruction. The affected cases were 22 middle-aged male dogs (mean age 4·9 years) of large and giant breeds (mean bodyweight 36·7 kg). Nine dogs had had periodic clinical signs for longer than one year, one for seven months and eight for two to five weeks, while in four dogs signs had begun four to five days before referral. All dogs received the α-sympatholytic agent prazosin as an initial treatment and in 11 it remained the only therapy. There was a good effect in seven and a moderate response in the other four dogs. In one dog, prazosin was ineffective and was replaced by diazepam, which markedly reduced the signs. Three other dogs required frequent catheterisation and antibiotics were administered. These dogs responded favourably. Another three dogs with evidence of impaired bladder contractility were also treated with the parasympathomimetic agent carbachol. One did not improve and was euthanased. Four dogs developed bladder paralysis and severe infectious cystitis. Only one of these could be managed satisfactorily by long-term administration of prazosin, carbachol and antibiotics, and the others had to be euthanased.     

Hydrocolpos in dogs: surgical treatment in two cases

Two young female dogs were diagnosed with hydrocolpos as a result of a congenital vaginal obstruction. In one dog, hydrocolpos had led to faecal tenesmus; in the other, the condition was an incidental finding during laparotomy. Diagnostic tests included vaginoscopy, ultrasonography and retrograde vagino-urethrocystography. In both dogs, the obstruction was located at the junction between the caudal vagina and the vaginal vestibule. Anastomosis of the caudal vagina and vestibule through an episiotomy was successful in both cases.     

Transplacental Transfer of Iron in the Water Buffalo (Bubalus bubalis): Uteroferrin and Erythrophagocytosis

The objectives of this investigation were to understand transplacental transport of iron by secreted uteroferrin (UF) and haemophagous areas of water buffalo placenta and clarify the role(s) of blood extravasation at the placental‐maternal interface. Placentomes and interplacentomal region of 51 placentae at various stages of gestation were fixed, processed for light and transmission electron microscopy, histochemistry and immunohistochemistry. Haemophagous areas were present in placentomes collected between 4 and 10 months of pregnancy. Perl’s reaction for ferric iron was negative in placentomes, but positive in endometrial glands. Positive staining for UF indicated areas in which it was being taken up by phagocytosis and/or fluid phase pinocytosis in areolae of the interplacentomal mesenchyme, with little staining in endometrial stroma. Imunohistochemistry detected UF in trophectoderm of haemophagous regions of placentomes and in other parts of the foetal villous tree, but the strongest immunostaining was in the epithelial cells and lumen of uterine glands. Ultrastructural analyses indicated that erythrophagocytosis was occurring and that erythrocytes were present inside cells of the chorion that also contained endocytic vesicles and caveolae. Results of this study indicate that both the haemophagous areas of placentomes and the areolae at the interface between chorion and endometrial glands are important sites for iron transfer from mother to foetal‐placental tissues in buffalo throughout pregnancy.     

Electrical conductivity in the precambrian lithosphere of western canada

The subcrustal lithosphere underlying the southern Archean Churchill Province (ACP) in western Canada is at least one order of magnitude more electrically conductive than the lithosphere beneath adjacent Paleoproterozoic crust. The measured electrical properties of the lithosphere underlying most of the Paleoproterozoic crust can be explained by the conductivity of olivine. Mantle xenolith and geological mapping evidence indicate that the lithosphere beneath the southern ACP was substantially modified as a result of being trapped between two nearly synchronous Paleoproterozoic subduction zones. Tectonically induced metasomatism thus may have enhanced the subcrustal lithosphere conductivity of the southern ACP.     

Inherited disorders: the comparative picture

When confronted with a novel familial disorder, veterinarians should consult McKusick's catalogue of inherited disorders in humans, called Mendelian Inheritance in Man (MIM), or its online version (OMIM), to see whether a similar disorder has been reported in humans. They should also consult the other readily available sources of comparative information on mice and domesticated species. Increasingly, such consultations can be conducted on the Internet via the World Wide Web. If it is thought that an animal disorder is homologous with a human disorder, publications describing the animal disorder should include the MIM number(s) for that disorder. Future research can then test the hypothesis of homology, until a consensus is reached.     

Chondrodysplasia in Australian Dexter cattle

Objective To describe the occurrence of chondrodysplasia in Australian Dexter cattle.
Design A pathological and genetic case report.
Procedure Congenital lethal chondrodysplasia was studied in two female Dexter foetuses aborted mid to late gestation. Clinicopathological findings including histological changes in limb bones, and analysis of pedigree information were evaluated.
Results Characteristic features of congenital lethal chon-drodysplasia (Dexter bulldog) include abortion, disproportionate dwarfism, a short vertebral column, marked micromelia, a relatively large head with retruded muzzle, cleft palate and protruding tongue and a large abdominal hernia. Histological changes in limb bones are consistent with failure of endochondral ossification. Dexter chondrodysplasia is considered to be inherited in an incompletely dominant manner with the homozygous form producing the congenital lethal condition. A preliminary minimum estimate of heterozy-gote frequency is 19% within the registered Australian Dexter herd, based on analysis of the contribution of three obligate heterozygotes whose semen has been widely used by artificial insemination in Australia.
Conclusion Dexter chondrodysplasia is present in Australian cattle and further cases of the homozygous form, congenital lethal chondrodysplasia, are likely to occur.
Recommendation It is requested that spleen and liver tissue from bulldog foetuses and blood from their parents be collected to assist research into Dexter chondrodysplasia.     

En bloc ligation of the thoracic duct in twelve dogs with idiopathic chylothorax

Twelve dogs with idiopathic chylothorax were treated by en bloc ligation of the thoracic duct. Six dogs recovered completely. Minimal follow-up in this group was 12 months. Five dogs were euthanized within 5 months of surgery because of persisting liquothorax: two with chylous and three with non-chylous effusions. One dog was euthanized 2 months after surgery because of a recurrence of dyspnoea. It is concluded that the results are comparable with those of a previously described surgical treatment; however, the technique described here is less complicated because it does not require mesenteric lymphangiography.