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.     

A preliminary equine abuse policy with potential application to veterinary practice

An equine abuse policy was developed as an adjunct to an equine management survey. If at least 3 of 5 categories caused concern, a report to the authorities was indicated. The policy was not used but, in the absence of other guidelines, it might assist veterinarians considering potential abuse cases.     

The Sustainability of Quinoa Production in Southern Bolivia: from Misrepresentations to Questionable Solutions. Comments on Jacobsen (2011, J. Agron. Crop Sci. 197: 390–399)

Reviewing the situation of quinoa production in southern Bolivia, Jacobsen (2011, J. Agron. Crop Sci. 197: 390) argues that the booming export market has a negative effect on the environment and on the home consumption of quinoa, thereby leading to an environmental disaster in the region. In view of the scarcity of scientific knowledge on the rapid social and environmental dynamics in the region, we consider that Jacobsen’s review misrepresents the situation of quinoa production in southern Bolivia. Specifically, we argue that (i) the data presented by Jacobsen (2011, J. Agron. Crop Sci. 197: 390) do not support any drop in quinoa crop yield supposed to reflect soil degradation and (ii) his demonstration regarding home consumption of quinoa is ill‐founded from both a nutritional and a cultural point of view. We suggest that the diffusion of the arguments exposed by Jacobsen (2011, J. Agron. Crop Sci. 197: 390), because of their flaws, might have strong negative impacts on those concerned with sustainable food production and fair‐trade with developing countries. We conclude that, rather than reinforced agro‐technical controls on local farmers, the rising competition in the international quinoa market requires a shift towards an ethical economy and ethical research cooperation with quinoa producers.     

The Advantages of Combining Low‐Density Lipoproteins with Glutamine for Cryopreservation of Canine Semen

Twenty sperm samples from five dogs were frozen in liquid nitrogen at ?196°C in 16 different media, two control media containing 20% egg yolk and 6% low‐density lipoproteins (LDL); 10 test media containing 6% LDL (the active cryoprotective ingredient of chicken egg yolk) combined with 10, 20, 30, 40, 50, 60, 70, 80, 90, and 100 mmol of glutamine respectively at 4%, 5%, 7%, and 8% LDL. Following thawing, sperm mobility was assessed using an image analyser, HAMILTON THORN CERROS 12. The percentage of mobile spermatozoa was 62.05% in the 6% LDL + 20 mmol glutamine medium compared with 48.90% in the egg yolk‐based medium (p < 0.05) or 57.55% for the 6% LDL medium (p < 0.05). Furthermore, in most cases, the motility parameters (average path velocity, curvilinear velocity, straight line velocity) in the 6% LDL + 20 mmol glutamine medium, were superior, to a statistically significant extent, to those in the control media. Finally, the 6% LDL + 20 mmol glutamine combination provides spermatozoa with better protection during freezing than egg yolk or the 6% LDL medium alone in terms of acrosome integrity (fluorescein isothiocyanate–Pisum sativum agglutinin test: p < 0.05), the flagellar plasma membrane (hypo‐osmotic test: p < 0.05 for 6% LDL), the DNA (acridine orange test; no significant difference) and the integrity of the acrosome (Spermac^® test: no significant difference).     

Centuries-old logging legacy on spatial and temporal patterns in understory herb communities

Understory herb communities in the Southern Appalachians are among the highest biodiversity plant communities in North America. In the mid-1990s, a debate began over whether understory herb communities recover to their pre-disturbance states following logging. Studies showing reduced herb-layer diversity in previously logged forests were criticized for not accounting for intersite environmental heterogeneity. More recent studies have addressed environmental heterogeneity, but have neglected long-term recovery by using “mature forests” as young as 80 years old as the benchmark for diversity comparison, even though old growth stands have disturbance return intervals exceeding 500 years. Here we address concerns clouding previous studies of high-diversity Appalachian herb communities and investigate their long-term recovery by comparing paired sites of old growth forest and forest logged 100–150 years ago. We found that species richness and individual abundance is greater in old growth forests than mature forests and that species composition differed significantly between the two. Turnover in species among old growth and mature forests accounted for 11% of the total species richness and was significantly greater than expected. Species turnover at intermediate (5–50 m) and landscape-scales (>10 km) contributed the most towards total species richness. Herb communities in rich cove forests have successional trajectories that exceed 150 years, with important community changes still occurring long after the forest returns to what has been previously termed a “mature” state. To conserve the diverse herb layer, we conclude that mature forest stands are too young to serve as baselines for recovery, landscape-scale preservation of multiple forest stands is needed to maximize species richness, and maintaining 100–150-year logging rotations will likely lead to loss of biodiversity.     

Surgical correction of double-chambered right ventricle in dogs

Double-chambered right ventricle (DCRV) is possibly an emerging congenital cardiac anomaly in dogs. The defect causes clinical and pathophysiologic signs similar to those of congenital pulmonic stenosis in dogs but has distinct diagnostic features, breed predilections, and implications for treatment. The defect is often associated with clinical signs early in life. Surgical correction of DCRV can be undertaken with the aid of cardiopulmonary bypass and offers the prospect of an improved clinical outcome.     

Comparison of one-layer (continuous Lembert) versus two-layer (simple continuous/Cushing) hand-sewn end-to-end anastomosis in equine jejunum

OBJECTIVE: To evaluate single and double layer end-to-end anastomosis in equine jejunum. STUDY DESIGN: Experimental in vitro study. ANIMALS: Mid-jejunal sections from 12 adult horses without gastrointestinal disease. METHODS: Jejunal end-to-end anastomoses were performed by a continuous Lembert pattern or a simple continuous pattern oversewn with a Cushing pattern. Jejunal segments were distended with fluid at 1 L/min, and intraluminal pressure at failure, and mode of failure were recorded. Bursting pressure and bursting wall tension were calculated. Anastomosis construction time and degree of luminal reduction were recorded. Results- Single layer anastomoses were constructed in less time than 2-layer anastomoses. Both anastomotic techniques resulted in luminal reduction compared with control tissue; however, the reduction was smaller with a 1-layer continuous Lembert anastomosis. No differences were noted in bursting pressure or bursting wall tension between groups. CONCLUSIONS: Anastomosis using a 1-layer continuous Lembert pattern resulted in a larger stoma, was faster to perform, and as strong as a 2-layer anastomosis. CLINICAL RELEVANCE: Use of a 1-layer continuous Lembert pattern for jejunojejunosotomy may be beneficial by decreasing anastomosis time and produce a larger stoma than a 2-layer anastomosis.