Regional variations in the nematode worm populations of breeding ewes in New Zealand

AIM: To determine whether the generic composition of nematode parasites in lactating ewes varies between geographic regions in New Zealand and whether age and fecundity of ewes affect nematode egg output. METHODS: Four ram breeding properties in each of the northern (NNI) and southern (SNI) North Island and the northern South Island (NSI) regions, together with six properties in the southern South Island (SSI) were investigated. Faecal samples were obtained on one occasion, 2-6 weeks after lambing, from at least 60 ewes on each property, stratified according to age and reproductive status. Nematode eggs were counted and coprocultures prepared to identify genera present. Information on the history of anthelmintic use on each property was also collected. RESULTS: Highest faecal egg counts (FEC) were observed from ewes in the NNI and SSI regions. Lambed hoggets and twin-rearing two-tooth ewes had higher FEC than their unlambed or single-lamb-rearing contemporaries, respectively. However, no significant effect of reproductive effort on FEC was demonstrated in mixed-aged ewes. Significant regional differences in generic composition of nematode parasites were observed: Teladorsagia spp (also referred to as Ostertagia spp) eggs made up 56% of total eggs shed from sheep in the SSI compared with14% in the NNI, and values for Haemonchus spp were 1%and 24% for these same regions, respectively. Trichostrongylus colubriformis and T. vitrinus together made up 7, 15, 13 and15% of eggs counted from sheep in the SSI, NSI, SNI and NNI, respectively. CONCLUSIONS: More comprehensive epidemiological information may suggest regional-specific approaches to the management of nematode parasites in ewes should be devised in the future.     

Angularis oris axial pattern buccal flap for reconstruction of recurrent fistulae of the palate

OBJECTIVE: To describe the use of an axial pattern flap based on the angularis oris artery and vein for reconstruction of palate defects. STUDY DESIGN: Clinical case report ANIMALS: Two dogs with recurrent oronasal fistulae. METHODS: Oronasal fistulae previously treated by buccal mucosal random pattern flaps that subsequently dehisced were repaired using an angularis oris-based buccal tissue axial pattern flap. This flap was developed by full thickness incision of the cheek tissue, excluding the skin, about the angularis oris vascular pedicle resulting in a vascularized flap covered by oral mucosa on one side. RESULTS: In one dog, the repair was intact and healed 6 months after surgery. In the second dog with a fistula that resulted because of radiation necrosis, approximately 95% of the defect healed with a small (<1.0 cm(2)) area of dehiscence. Repair of this persistent fistula with a random pattern buccal flap failed and this small fistula remained with minimal clinical signs. CONCLUSION: An axial pattern flap based on the angularis oris artery and vein can be used to repair difficult or recurrent palate defects. CLINICAL RELEVANCE: Angularis oris axial pattern flaps provide an additional effective option for repair of defects in the hard and soft palate to the distal gingival margin of the canine tooth or beyond, depending on skull conformation. Advantages of this flap include its highly vascular and robust character, high degree of mobility and a surface of tough buccal mucosa.     

Use of intraluminal nitinol stents in the treatment of tracheal collapse in a dog

Tracheal collapse is a common problem that is typically observed in middle-aged and older small-breed dogs. It is a structural, obstructive airway disease with a dynamic component that can affect the intra- and extrathoracic portions of the trachea and mainstem bronchi. Many methods of treatment have been suggested, including medical management and provision of extraluminal and intraluminal support. All techniques used to treat intrathoracic and mainstem bronchial collapse have been associated with major complications or limitations. This report describes the implantation of intraluminal nitinol stents to successfully treat intrathoracic as well as extrathoracic tracheal collapse in a dog. The stents are composed of material that has characteristics similar to those of the trachea; nitinol stents may provide a method of supporting intrathoracic tracheal and mainstem bronchial collapse in dogs.     

Current distribution of sarcoptic mange in wombats

Objective To determine the distribution and prevalence of sarcoptic mange in wombats, particularly the common wombat ( Vombatus ursinus ).
Design Questionnaire survey in two parts.
Procedure Questionnaires were distributed to biologists, rangers, animal carers and naturalists. Part 1 of the questionnaire aimed to determine the present distribution of sarcoptic mange in wombats (103 responses). Part 2 invited respondents to assess the prevalence of sarcoptic mange in wombats over a 3 month period (four responses). Information on wombats from 66 localities was received. Each locality represented an area of about 2500 km².
Results Mange was observed at 93% of localities surveyed and Sarcoptes scabiei was present in common wombats at 52% of localities. Sarcoptic mange was highly prevalent (22%) in two common wombat populations in Victoria. Anecdotal evidence suggested that mange epizootics are sporadic, cause significant morbidity and mortality and have a substantial effect on local abundance. The respondents did not report sarcoptic mange in either northern hairy-nosed wombats ( Lasiorhinus krefftii ) or southern hairy-nosed wombats ( Lasiorhinus latifrons ).
Conclusions Sarcoptic mange occurs in common wombat populations throughout the range of the common wombat including Tasmania and Flinders Island. While mange epizootics are sporadic, they have the potential to threaten the long-term survival of small, remnant populations.     

Confirmation of spatial patterns and temperature effects in Bluetongue virus serotype-8 transmission in NW-Europe from the 2007 reported case data

Two separate analyses were carried out to understand the epidemiology of Bluetongue virus serotype 8 (BTV-8) in 2007 in North West Europe: First, the temporal change in transmission rates was compared to the evolution of temperature during that season. Second, we evaluated the spatio-temporal dynamics of newly reported outbreaks, to estimate a spatial transmission kernel. For both analyses, the approach as used before in analysing the 2006 BTV-8 epidemic had to be adapted in order to take into account the fact that the 2007 epidemic was not a newly arising epidemic, but one advancing from whereto it had already spread in 2006. We found that within the area already affected by the 2006 outbreak, the pattern of newly infected farms in 2007 cannot be explained by between-farm transmission, but rather by local re-emergence of the virus throughout that region. This indicates that persistence through winter was ubiquitous for BTV-8. Just like in 2006, we also found that the temperature at which the infection starts to spread lies close to 15 °C. Finally, we found that the shape of the transmission kernel is in line with the one from the 2006 epidemic. In conclusion, despite the substantial differences between 2006 and 2007 in temperature patterns (2006 featured a heat wave in July, whereas 2007 was more regular) and spatial epidemic extent, both the minimum temperature required for transmission and the transmission kernel were similar to those estimated for the 2006 outbreak, indicating that they are robust properties, suitable for extrapolation to other years and similar regions.     

Spatial Variability of Turbulent Mixing in the Abyssal Ocean

Ocean microstructure data show that turbulent mixing in the deep Brazil Basin of the South Atlantic Ocean is weak at all depths above smooth abyssal plains and the South American Continental Rise. The diapycnal diffusivity there was estimated to be less than or approximately equal to 0.1 x 10(-4) meters squared per second. In contrast, mixing rates are large throughout the water column above the rough Mid-Atlantic Ridge, and the diffusivity deduced for the bottom-most 150 meters exceeds 5 x 10(-4) meters squared per second. Such patterns in vertical mixing imply that abyssal circulations have complex spatial structures that are linked to the underlying bathymetry.     

BOOK REVIEW

ECG Interpretation in Dogs and Cats, Video produced by Provet for the Unit of Veterinary Continuing Education of the Royal Veterinary College     

Outcome of accelerated radiotherapy alone or accelerated radiotherapy followed by exenteration of the nasal cavity in dogs with intranasal neoplasia: 53 cases (1990-2002)

OBJECTIVE: To compare long-term results of radiotherapy alone versus radiotherapy followed by exenteration of the nasal cavity in dogs with malignant intranasal neoplasia. DESIGN: Retrospective study. ANIMALS: 53 dogs with malignant intranasal neoplasia. PROCEDURE: All dogs underwent radiotherapy consisting of administration of 10 fractions of 4.2 Gy each on consecutive weekdays. For dogs in the surgery group (n=13), follow-up computed tomography was performed, and dogs were scheduled for surgery if persistent or recurrent tumor was seen. RESULTS: Perioperative complications for dogs that underwent surgery included hemorrhage requiring transfusion (2 dogs) and subcutaneous emphysema (8). Rhinitis and osteomyelitis-osteonecrosis occurred significantly more frequently in dogs in the radiotherapy and surgery group (9 and 4 dogs, respectively) than in dogs in the radiotherapy-only group (4 and 3 dogs, respectively). Two- and 3-year survival rates were 44% and 24%, respectively, for dogs in the radiotherapy group and 69% and 58%, respectively, for dogs in the surgery group. Overall median survival time for dogs in the radiotherapy and surgery group (477 months) was significantly longer than time for dogs in the radiotherapy-only group (19.7 months). CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that exenteration of the nasal cavity significantly prolongs survival time in dogs with intranasal neoplasia that have undergone radiotherapy. Exenteration after radiotherapy may increase the risk of chronic complications.     

The effect of cisterna chyli ablation combined with thoracic duct ligation on abdominal lymphatic drainage

OBJECTIVE: To evaluate the effect of cisterna chyli ablation (CCA) and thoracic duct ligation (TDL) on abdominal lymphatic drainage in normal dogs. STUDY DESIGN: Experimental study. ANIMALS: Nine female beagle dogs. METHODS: TDL was performed in 3 dogs and was combined with CCA (CCA-TDL) and local omentalization in 6 dogs. Contrast lymphangiography was attempted in all dogs immediately before and after TDL. Dogs were reanesthetized at 31-37 days for lymphatic studies by new methylene blue (NMB) injection into a mesenteric lymph node and by contrast lymphangiography. RESULTS: In 6 CCA-TDL dogs, 2 had direct shunting of contrast from the lymphatic system into major abdominal veins, 3 had contrast material that dissipated into abdominal vessels within the mesenteric root, and 1 had shunting into the azygous vein. NMB was not observed within the omental pedicle after CCA-TDL. Chylous drainage was by the azygous vein in all 3 TDL dogs. CONCLUSIONS: CCA-TDL disrupted chylous drainage to the thoracic duct and resulted in direct intraabdominal lymphaticovenous anastomoses identified by shunting of lymphatic flow directly into the abdominal vasculature in 5 of 6 CCA-TDL dogs. Omentalization of the cisternal ablation site was not beneficial in augmenting extrathoracic lymphatic drainage and is not recommended with CCA-TDL. CLINICAL RELEVANCE: CCA-TDL represents a novel approach to surgical redirection of chylous drainage to the venous circulation outside of the thorax and may be useful in the treatment of spontaneous chylothorax in the dog.