Evaluation of the Cranial Rectus Abdominus Muscle Pedicle Flap as a Blood Supply for the Caudal Superficial Epigastric Skin Flap in Dogs

This study evaluates the cranial rectus abdominus muscle pedicle flap as the sole blood supply for the caudal superficial epigastric skin flap. This flap was composed of a cranially based rectus abdominus muscle pedicle flap that was attached to the caudal superficial epigastric island skin flap (including mammary glands 2 to 5) via the pudendoepigastric trunk. Selective angiography of the cranial epigastric artery in eight cadaver dogs proved that the arterial vasculature in the cranial rectus abdominus was contiguous with that in the caudal superficial epigastric skin flap. In the live dog study, three of six of the flaps failed because of venous insufficiency. Necrosis of mammary gland 2 occurred in two of six flaps. One of six flaps survived with the exception of the cranial most aspect of mammary gland 2. Angiography of the cranial epigastric artery proved that arterial blood supply to these flaps was intact. Histological evaluation of the failed flaps showed full-thickness necrosis of the skin and subcutaneous tissues, the presence of severe congestion, and venous thrombosis. Retrograde venous blood flow through the flap was inconsistent, and hence resulted in failure of this myocutaneous flap. Use of this flap for clinical wound reconstruction cannot be recommended.     

Autologous Platelet Concentrates as a Treatment of Horses with Osteoarthritis: A Preliminary Pilot Clinical Study

The clinical effect of the intra-articular injection of an autologous platelet concentrate (PC) in four horses with osteoarthritis was evaluated. The degree of lameness and joint effusion and clinical follow-up were recorded. Three injections of PC were performed at 2-week intervals. Horses were evaluated before each injection and two months after the last treatment. Clinical follow-up was conducted for 1 year. Count of platelets, leukocytes, and determination of transforming growth factor beta-1 (TGF-β₁) levels per milliliter PC were performed, as well as leukocyte count, cytology, and protein levels in synovial fluid. PC produced a statistically significant improvement in both the degree of lameness and joint effusion (P < .05). The most marked improvement was observed 2 months after the last treatment and apparently persisted for 8 months. A mean of 250 ± 71.8 × 10⁶ platelets, 8.68 ± 3.78 leukocytes × 10⁶, and 12,515 ± 2,443 pg of TGF-β₁ per milliliter PC were obtained. The evaluated synovial fluid parameters remained between normal values. No adverse clinical signs resulted from this treatment. Despite the seemingly positive effects of this substance, the clinical use of PC cannot be recommended until further studies with higher numbers of cases and longer follow-up can be undertaken.     

扬子鳄胚胎背部皮肤及鳞甲的发生

本文观察了１６例不同时间的扬子鳄（Ａｌｌｉｇａｔｏｒｓｉｎｅｎｓｉｓ）胚胎背部皮肤及鳞甲的形态及组织发生过程。孵化第２０天，来自胚胎中胚层生皮节的间充质细胞开始向原始表皮下迁移，表皮仅具周皮层与生发层两层细胞。第２８天背部鳞片开始明显，左右鳞片之间出现很浅的鳞间沟，前后鳞片交界处的原始表皮、真皮层开始向外突出形成鳞甲原基。第３４天鳞甲原基突出伸长，第４０天背鳞的纵崤明显。第３４～５０天中，鳞甲后缘基部的表皮层向鳞甲前缘基部的真皮层不断内陷，鳞甲显著伸长并向体后方水平伸出。背部表皮在孵化第３４天出现三层细胞，第４０天周皮细胞中开始出现色素沉集。第５０天表皮具四层细胞，周皮层细胞中出现大量色素沉集。第６０天表皮分层与成体时相似，周皮层已退化。孵化第３４天真皮层细胞形态出现多样化，第４０天真皮可分上、下两层。第５０天真皮上层中形成交织的胶原纤维网，下层中形成平行走向的胶原纤维。本文简要讨论了扬子鳄鳞甲的形态发生特点。     

Retroversion of the Epiglottis as a Complication of Endotracheal Intubation in the Horse A Pilot Study

As part of a study of possible causes of postoperative pulmonary complications of general anesthesia in the horse, lateral cervical radiographs were taken after endotracheal intubation in nine randomly selected horses. The epiglottis was found to be retroverted in three. Subsequently, the effects of epiglottic retroversion during anesthesia on postoperative laryngeal function were investigated experimentally in three horses by fluoroscopy. No untoward sequelae were observed. Prophylaxis and potential adverse effects of this previously unreported complication of endotracheal intubation in the horse are discussed.     

Suitability of biocompost as a bedding material for stabled horses: respiratory hygiene and management practicalities

REASONS FOR PERFORMING STUDY: Bedding material in stables has an important influence on air hygiene and information on the suitability of biocompost and wood shavings is incomplete. OBJECTIVES: To compare the suitability and benefit of biocompost and wood shavings as bedding in horse stables and to determine key air factors for the evaluation of the potential impact of these materials on respiratory health. METHODS: The study was conducted in a naturally ventilated stable with 4 horses. Air hygiene parameters were measured 24 h/day for 7 days with each bedding type: ammonia (NH3), inhalable and respirable dust, endotoxins, colony forming units (CFU) of total mesophilic bacteria, fungi, actinomycetes and thermophilic actinomycetes. Both bedding materials were analysed for general chemical composition, particle size distribution and natural microbial content. The animals' behaviour was monitored by video cameras, and their health and cleanliness status determined by clinical and visual examination. RESULTS: Concentrations of NH3, dust, endoxins and fungi were significantly higher during the monitoring period with wood shavings than with biocompost. In contrast concentrations of mesophilic bacteria, mesophilic actinomycetes and thermophilic actinomycetes microbial pollutants were highest with biocompost. The water content of bulk biocompost was considerably higher than that of wood shavings. Particles < or = 0.4 mm were not detectable in bulk wood shavings. The concentration of thermophilic actinomycetes by weight in raw biocompost was 639 times higher than in raw wood shavings. No significant differences were observed in the time spent by the horses lying down. The biocompost material tended to adhere more intensively to the animals' hair coat. Horses showed no clinical signs indicating any adverse effects of the biocompost material during the trials. CONCLUSIONS: Biocompost cannot be recommended as bedding material for horses in stables, because the concentration of thermophilic actinomycetes and other agents that elicit and maintain recurrent airway obstructions was significantly higher with biocompost than with wood shavings. To ensure the well-being of horses, any new bedding material must be tested very carefully before it is introduced to the market.     

The Intercondylar Fossa of the Normal Canine Stifle: An Anatomic and Radiographic Study

The intercondylar fossa (ICF) in dogs consists of a cranial outlet, intercondylar shelf, caudal arch, caudal outlet, a medial wall, and a lateral wall. The normal cranial outlet is bell-shape and, in mixed-breed dogs (mean body weight 19.2 kg, N = 21), measured 5.8 mm cranially, 8.1 mm centrally, and 10.3 mm caudally. The ICF is oriented 12° from the dorsal plane of the femoral diaphysis and obliqued 7°, proximolateral to distomedial, in the sagittal plane. To adjust for dog size, a fossa width index (FWI) was calculated by dividing the cranial outlet width by the distance between epicondyles. The normal FWI as determined in this study was 0.18 cranially, 0.25 centrally, and 0.32 caudally. The fossa height index was 0.31. Contact between the ICF and the cranial cruciate ligament began at about 115° of extension. The contact area moved cranially in the intercondylar fossa as the stifle was extended. Evaluation of the ICF can be performed radiographically but positioning is critical.     

大雁生殖系统的解剖学和组织学研究

实验对生殖季节与非生殖季节的大雁生殖系统进行了组织学研究。大雁雌性生殖系统左侧发育，右侧退化。生殖系统由卵巢、输卵管、交际器组成。输卵管包括漏斗部、蛋白分泌部、峡部、子宫与阴道五个部分。卵巢表面无浆膜覆盖，覆以单层生殖上皮，由浅部的皮质和深部髓质组成，皮质内含各级卵泡。雄性生殖系统由精巢、输精管、睾丸旁导管系统和交接器组成。精巢的基本结构单位为曲精细管，外层包被着浆膜，其下是白膜，白膜结缔组织伸入精巢实质部，呈网状分布，繁殖季节的睾丸实质内充满曲细精管。     

Evaluation of Recombinant Canine Granulocyte Colony-Stimulating Factor as an Inducer of Granulopoiesis: A Pilot Study

Five healthy young adult dogs were given recombinant canine granulocyte colony-stimulating factor (rcG-CSF) at a dosage of 5 micrograms/kg/day subcutaneously for 4 weeks to evaluate the effect on complete blood cell counts. The mean neutrophil counts +/- standard deviation (SD) increased significantly (P less than 0.01) from 6,537/microliters +/- 1,726 (range, 4,950-9,512/microliters) to 26,330/microliters +/- 7,066 (range, 15,368-35,785/microliters) within 24 hours after the first injection of rcG-CSF. Mean monocyte counts +/- SD were significantly increased (P less than 0.05) from baseline values of 751/microliters +/- 168 (range, 444-891/microliters) to 2,514/microliters +/- 878 (range, 1,740-3,752/microliters) on day 5 of rcG-CSF administration. Mean neutrophil and monocyte counts (+/- SD) continued to increase reaching a maximum of 72,125/microliters +/- 15,073 (range, 50,915-96,278/microliters) and 3,972/microliters +/- 2,621 (range, 685-8,030/microliters), respectively by day 19. These increased neutrophil and monocyte counts were maintained until the administration of rcG-CSF was stopped. Blood counts returned to normal within 5 days after discontinuing the rcG-CSF. One week after discontinuing treatment, rcG-CSF was started again at 5 micrograms/kg/day subcutaneously. Within 48 hours following administration of rcG-CSF, mean neutrophil counts +/- SD increased from 5,860/microliters +/- 1,819 (range, 3,720-8,650/microliters) to 57,444/microliters +/- 8,173 (range, 43,983-68,278/microliters). Myeloid:erythroid ratios increased from a mean of 1.63:1 on day 1 prior to administration of rcG-CSF to 3.3:1 on day 10 in three dogs for which bone marrow samples were evaluated. Recombinant canine G-CSF did not cause clinically significant toxicosis in any of the dogs.     

Collateral Ligaments of the Tarsocrural Joint An Anatomic and Functional Study

Forty canine hock joints were used to study the anatomy and function of the medial and lateral tarsocrural collateral ligament complexes. Dissection of the ligaments was used to describe the anatomic arrangement, and location and tenseness in various positions. The component parts of the ligament complexes were evaluated for their contribution to stability of the tarsocrural joint. The medial and lateral tarsocrural collateral ligament complexes were composed of several components. The medial tibiotalar and lateral calcaneofibular short component parts were important static joint stabilizers in both flexion and extension. The long medial and lateral ligaments and the medial tibiocentral short component were less important in maintaining joint stability in flexion but were important in extension. The stability of the joint as a whole did not depend on any individual ligament component, but rather all components of the ligament complex, including the joint capsule and malleoli, acted together to stabilize the joint.     

Superficial Osteitis and Sequestrum Formation as a Result of Skin Avulsion in the Horse

Metatarsal injuries with exposed bone are described in seven horses. Superficial osteitis and sequestrum formation occurred in six of the seven horses. The basic pathophysiology includes local vascular stasis leading to ischemic necrosis of osteocytes and establishment of bacterial infection within dead bone. Radiographic features of superficial osteitis and sequestrum formation include reactive periosteal new bone formation, an area of radiodense necrotic bone (sequestrum) surrounded by a radiolucent zone of granulation tissue, which in turn, is surrounded by an area of increased radiodensity (involucrum). The presence of a sequestrum may usually be confirmed radiographically by 12–14 days after injury. Surgical management included wound debridement, wound irrigation, bandaging or casting, sequestrectomy and skin grafting. Five of the seven patients required sequestrectomy, in one the sequestrum disappeared without removal. Mixed bacterial populations were commonly found in the wounds. No specific etiologic agent was associated with sequestrum formation.     

Vascular hamartoma as the cause of hind limb lameness in a horse

We report a 5-year-old gelding with a rare benign tumour of 2-month duration in the subcutis of the hind limb that presented with lameness. Physical examination revealed normal vital signs. Laboratory findings were within normal ranges. No bone abnormalities were detected on radiographic examination of the affected area. Bloody fluid was obtained by aspiration. Through an I-shape skin incision the tumour was excised en-block. Microscopic study showed a vascular hamartoma characterized by cavernous haemangiomatous tissue and proliferation of multiple vessels of variable diameter. This report highlights the importance of limb vascular hamartoma, as an infrequent lesion, in the differential diagnosis of lameness in the horse.     

Muscle Fibre Composition of the Bovine Tail: A Pilot Study

A bovine tail was cross-sectioned at four vertebrae, to expose its muscles - dorsal extensors, ventral flexors and the lateral flexors that pass between the transverse processes. Muscle cross-sectional areas were measured at these faces and muscle sections were stained to distinguish slow and fast fibre types. From the muscle and fibre area data and fibre type occurrences, preliminary conclusions are drawn about the role of different muscles. The tail as a model for muscle studies is briefly discussed.