An anatomical and histological study of the sciatic nerve, relating to peripheral nerve injuries in the dog and cat

The gross anatomical and histological features of the sciatic, peroneal and tibial nerves in the dog and cat are described with a view to explaining the vulnerability of these nerves to trauma.     

Penile prolapse and urethral obstruction secondary to lymphosarcoma of the penis in a dog

A 5-year-old Chihuahua presented for clinical signs of dysuria and penile prolapse. Radiographic studies identified a urethral obstruction distal to the junction of the proximal and middle third of the os penis that appeared to be secondary to swelling of the penis. Penile resection combined with a scrotal urethrostomy was performed. Histopathological examinations of tissue samples of the body of the penis revealed lymphosarcoma. Lymphosarcoma of the penis is a rare finding in all species. It can occur as a primary tumor of the penis in dogs. Penile lymphosarcoma should be considered in the differential diagnosis of dogs affected with penile prolapse and dysuria.     

Infestation in the dog by the paralysis tick Ixodes holocyclus 1. Clinical and histological findings

Under laboratory conditions 8 dogs were infested with Ixodes holocyclus and the clinical signs and histological findings were recorded. Seven of the dogs developed clinical signs of the disease, died and were subjected to a post-mortem examination, while the eighth dog remained normal. The clinical signs were consistent between animals and enabled the course of the disease to be subdivided into 5 stages to facilitate analysis of data in future experiments. The most prominent feature of the disease was dysfunction of the efferent motor system although some disturbance of the afferent pathways and involvement of the autonomic nervous system did occur. The period elapsing between attachment of the ticks and onset of signs varied from 5.5 to 7 days, while the mean duration of the disease was 23.3 h. The histopathology demonstrated moderate to severe congestion of the liver, kidney and lungs, and in some lung sections pulmonary oedema was present.     

Hypertrophic scar in a dog: histological and clinical features

An adult male bullmastiff dog was treated for paraparesis and ataxia due to discospondylitis and disc herniation. At this time, the dog had a nonhealing ulcer between the pads of the left hindfoot. At re-evaluation, the dog had developed a large exophitic mass in the previously ulcerated area. Cytological examination revealed occasional spindle cells with mild atypia, and a soft tissue tumour was suspected. The mass was excised and submitted for histology. The lesion was characterized by superficial ulceration, an intermediate layer of granulation tissue and a deep portion containing vertically orientated capillaries and perpendicularly arranged fibroblasts and collagen. The histological features led to a diagnosis of hypertrophic scar. Eight weeks after surgery, the lesion recurred and was treated with an intralesional injection of methylprednisolone acetate. The lesion regressed in 10 days, but recurred after 3 months following severe self-trauma. Hypertrophic scars and keloids are two types of exuberant scarring reported in human beings, the pathogenesis of which is still unclear but seems to involve several cytokines, growth factors and inflammatory cells. The histological features identified in this case paralleled those reported in hypertrophic scars in humans. In this case, intralesional corticosteroid therapy was useful in the management of the lesion, but the severe self-trauma could have influenced the recurrence. Even if uncommon, hypertrophic scar should be included among the differential diagnoses of spindle cell tumours in dogs.     

Angiokeratoma: A benign vascular tumour of the dog

The angiokeratoma (AK) is a rare neoplasm of the nictitans and the conjunctiva of dogs. This report adds eight further cases to the two reported in the literature. The majority involved the nictitans of mature dogs of either sex with a possible predisposition in the English setter breed. Two occurred in the skin. In both locations, the AK had, as its characteristic feature, large dilated sinusoidal spaces abutting and infiltrating a hyperplastic epidermis. Compared to classical dermal haemangioendotheliomas, AKs are rare. In most cases, excision is curative.     

Comparative histological study of the reproductive system of the female llama (Lama guanicoe glama). I. Ovary]

In the present study a cytological, histological and morphometrical comparison between the ovaries of the llama, the cow and the sheep is presented, at two phases of the ovarian cycle. There were found differences in the amount of primordial and primary follicles, the size of secondary follicles and follicular cells, and type and distribution of the connective tissue inside the stroma of the ovary. It would be necessary to study the fine structure of the ovary and the so-called "embryological remnants", for its permanent appearance in most (50%) of the ovaries.     

Rectal hemorrhage associated with vascular ectasia in a young dog.

Rectal bleeding in a 7-month-old 13-kg sexually intact female mixed-breed dog was determined to be associated with vascular ectasia of the small intestine, descending colon, rectum, and anus. Microscopically, the telangiectasia was associated with lymphangiectasia and focal ulceration. Surgical intervention resulted in incomplete resection of the lesion and only temporary amelioration of clinical signs. The dog's age was compatible with a congenital origin for the defect, but an acquired cause could not be excluded.     

Penile self-mutilation as an unusual sign of a separation-related problem in a crossbreed dog

A two-year-old, male, crossbreed dog was presented for evaluation of licking, biting and severe self-mutilation of its penis, which resulted in ulcers and haemorrhagic preputial discharge. History revealed signs of separation anxiety such as active greeting behaviour, excessive vocalisation and intermittent episodes of licking of the penis when the dog was left alone. The owner reported that he had been hospitalised after a car accident, and he had no chance of seeing the dog. During that time, the behaviour progressed to frequent episodes of licking and biting of the penis. Three weeks of treatment with clomipramine in addition to the presence of the dog's brother, who was brought into the dog's living environment, appeared to produce a considerable degree of improvement. The purpose of this report is to contribute to an increased awareness within veterinary practice of unusual signs of separation anxiety such as penile self-mutilation.     

犬呼吸系统寄生虫

犬呼吸道系统的寄生虫大多不被人们了解,因而往往被忽视,常常耽误了治疗,本文对寄生于犬呼吸道而引起犬呼吸系统疾病的寄生虫作一介绍。一、寄生于犬鼻粘膜和鼻窦的寄生虫1、波姆氏优鞘线虫成虫仅几毫米长,呈线状寄生于鼻窦粘膜。从尸体粘膜取出时看上去象细线。虫卵卵壳表面有