Evaluation of wraps covering the distal aspect of pelvic limbs for prevention of bacterial strike-through in an ex vivo canine model

Objective— To determine differences in bacterial strike-through for materials commonly used to cover the distal aspect of the pelvic limb during operative site preparation.
Study Design— Randomized block design; ex vivo model.
Animals— Canine cadaveric pelvic limbs (n=40).
Methods— Pelvic limbs (n=40) were randomly assigned to 4 treatment groups: Group 1=Vetrap^™+sterile Coban^™; Group 2=latex glove+Vetrap^™+sterile Coban^™; Group 3=latex glove+Vetrap^™+sterile Coban^™+sterile latex glove+sterile Coban^™; and Group 4=latex glove+Vetrap^™+sterile disposable drape+sterile Coban^™. Limbs were contaminated with a standardized bacterial solution and routinely prepared using the assigned distal leg wrap. Bandages were fluid challenged with a saline (0.9% NaCl) solution-soaked laparotomy sponge for 30 seconds. The wrap surface was sampled for microbial culture before surgical preparation, immediately after, and 60 minutes after applying a sterile leg wrap.
Results— Bacterial growth occurred in all Group 1 cultures, 90% of Group 2 cultures, and none of the Group 3 and 4 cultures, 60 minutes after applying the sterile wrap.
Conclusion— A distal leg wrap of Vetrap^™+sterile Coban^™ is not effective in preventing bacterial strike-through.
Clinical Relevance— If similar results occur in the live animal, then a sterile impermeable barrier must be incorporated into the distal leg wrap to prevent bacterial strike-through.     

Evaluation of the recognition of Theileria parva vaccine candidate antigens by cytotoxic T lymphocytes from Zebu cattle

East Coast fever (ECF) is a highly fatal lymphoproliferative disease of cattle caused by Theileria parva, a tick-borne intracellular apicomplexan parasite. Parasite antigens that are targets of protective cytotoxic T lymphocyte (CTL) responses are required to formulate a sub-unit vaccine against ECF. A number of CTL target antigens have recently been identified and initial evaluation has shown their vaccine potential. This study aimed to evaluate whether these antigens were recognised by CTL obtained from six genetically diverse Zebu cattle immunized with a cocktail of T. parva stocks. T. parva Muguga specific polyclonal CD8(+) CTL lines were generated and confirmed to specifically lyse autologous infected cells. CTL recognition of autologous skin fibroblasts (iSF) transduced with recombinant modified vaccinia virus Ankara strain (MVA) expressing previously identified T. parva Muguga vaccine candidate antigens was evaluated using an IFN-gamma ELISpot assay. CTL lines from one of the four calves, BY120, responded specifically to cells infected with MVA expressing the antigen Tp2 and synthetic peptides were employed to map a new CTL epitope on this antigen. Immunoscreening of the T. parva genome with these CTL lines should identify novel antigens that will constitute valuable additions to the vaccine candidates currently being evaluated.     

Body temperature,activity patterns and hunting in free‐living cheetah: biologging reveals new insights

As one of the few felids that is predominantly diurnal, cheetahs (Acinonyx jubatus) can be exposed to high heat loads in their natural habitat. Little is known about long‐term patterns of body temperature and activity (including hunting) in cheetahs because long‐term concurrent measurements of body temperature and activity have never been reported for cheetahs, or, indeed, for any free‐living felid. We report here body temperature and locomotor activity measured with implanted data loggers over 7 months in 5 free‐living cheetahs in Namibia. Air temperature ranged from a maximum of 39 °C in summer to ?2 °C in winter. Cheetahs had higher (～0.4 °C) maximum 24‐h body temperatures, later acrophase (～1 h), with larger fluctuations in the range of the 24‐h body temperature rhythm (approximately 0.4 °C) during a hot‐dry period than during a cool‐dry period, but maintained homeothermy irrespective of the climatic conditions. As ambient temperatures increased, the cheetahs shifted from a diurnal to a crepuscular activity pattern, with reduced activity between 900 and 1500 hours and increased nocturnal activity. The timing of hunts followed the general pattern of activity; the cheetahs hunted when they were on the move. Cheetahs hunted if an opportunity presented itself; on occasion they hunted in the midday heat or in total darkness (new moon). Biologging revealed insights into cheetah biology that are not accessible by traditional observer‐based techniques.     

Assessing the impacts of domesticated versus wild ungulates on terrestrial small mammal assemblages at Telperion Nature Reserve,South Africa

Grazing by large mammals alters vegetation physiognomy, consequently changing habitat suitability for small mammal communities. We investigated the response of terrestrial small mammals to grazing by wild and domesticated ungulates at the boundary of a protected area (Telperion Nature Reserve) and surrounding cattle ranches in Mpumalanga, South Africa over two seasons. Fifteen paired grids were set on either side of the boundary fence at which small mammals were trapped in Sherman live traps placed flat on the ground. A total of 11 760 trap nights resulted in the capture of 187 animals belonging to 14 species (11 rodents, two shrews and one elephant shrew). The small mammal communities in grasslands grazed by domesticated or wild ungulates were similar in abundance, species richness, diversity and demographic parameters, likely due to the fact that vegetation structure of the two grazing systems was also similar. We used generalised linear models to show that rock and grass cover were plausible predictors of small mammal abundance in this system. Rock cover showed a positive relationship with small mammal abundance whilst grass cover showed a negative relationship. Our observations suggest that at the scale of our study and with the current stocking densities, wild and domesticated ungulates have similar impacts on the small mammal community.     

Triple antimicrobial therapy and acid suppression in dogs with chronic vomiting and gastric Helicobacter spp

BACKGROUND: Helicobacter pylori is a common cause of gastritis and peptic ulcers in humans. Many dogs, including those with gastritis and chronic vomiting, are infected with Helicobacter spp. HYPOTHESIS: Triple antimicrobial therapy will eradicate Helicobacter infection, improve gastritis, and reduce clinical signs. The addition of acid suppression medication will not improve results. ANIMALS: Twenty-four pet dogs with chronic vomiting and gastric Helicobacter spp. METHODS: Dogs were randomly assigned to triple antimicrobial therapy with or without famotidine. Gastroduodenoscopy was performed 4 weeks and 6 months after therapy. Helicobacter spp status was determined by histologic assessment of gastric mucosal biopsy specimens. RESULTS: Eradication rates for each treatment were not significantly different and combined were 75 and 42.9% at 4 weeks and 6 months, respectively. A greater improvement in gastritis scores occurred in dogs that became Helicobacter spp negative. Overall, the frequency of vomiting was reduced by 86.4%, but there were no differences between treatments. CONCLUSIONS AND CLINICAL IMPORTANCE: Eradication rates of Helicobacter spp with both treatments were not significantly different. Eradication rates at 6 months were modest, and more effective treatments should be developed. Acid suppression is not a necessary component of treatment protocols for dogs. Eradication of gastric Helicobacter spp was associated with improvement in gastritis scores. Dramatic reduction of the vomiting frequency occurred with both treatment protocols. Gastric Helicobacter spp may cause or contribute to chronic vomiting and gastritis in some dogs.     

DEVELOPMENT OF REFERENCE INTERVALS FOR THE LARGE INTESTINAL TRANSIT OF RADIOPAQUE MARKERS IN DOGS

Ten healthy dogs were fed 30 1.5 mm and 10 5 mm radiopaque markers (BIPS, MedID, Grand Rapids) mixed with sufficient quantities of a high fibre diet to meet 25% of their estimated daily caloric requirements. Abdominal radiographs were made at two hour intervals until 90% of the small and large markers had left the colon. The mean residence times (MRT) of each size of marker in the proximal, distal and total colon were calculated using kinetic analysis. The MRT's of the small markers were 4.9 hours (SD 4.4), 7.1 hours (SD 3.3) and 12.0 hours (SD 7.1) respectively. The MRT's of the large markers were not significantly different from the small markers except in the proximal colon where they were significantly shorter (3.2 hours, SD 2.3). Reference colonic filling and colonic transit curves for both sizes of markers were constructed. These may be useful to detect abnormal colonic transit in dogs.