Valentina Busin

Production impact of a targeted selective treatment system based on liveweight gain in a commercial flock

The sustainability of sheep production is hindered by anthelmintic resistance. Options to slow down or prevent resistance have been widely studied but their application in the field is still limited. In this study, the practical application and effect of a targeted selective treatment (TST) approach for the treatment of parasitic gastroenteritis was investigated in lambs (n = 385) over a 2 year period. At 14-day intervals during the grazing season, liveweight, breech soiling and anthelmintic treatments were individually recorded. Selection of lambs for anthelmintic treatment in the TST group was based on pre-calculated individual growth rates, with a matched cohort routinely treated (RT) with anthelmintic drug every 6 weeks. The adoption of a TST approach had no negative effect on the liveweight gains of the lambs, time to finishing or breech soiling measures compared to RT lambs; however a 50% decrease in anthelmintic treatment was observed in the TST group. The time to implement this system averaged 2 min per lamb. It is concluded that the TST could be suitable for commercial sheep farms, in association with automated weighing systems, potentially reducing selection for anthelmintic resistance, while having no negative effect on production.

Hepatogenous photosensitisation in Scottish sheep casued by Dicrocoelium dendriticum.

Dicrocoeliosis was identified as the probable predisposing cause of weight loss and hepatogenous photosensitisation affecting half of a group of 14 month-old ewe lambs on a farm on the Inner Hebridean island of Coll. Oral dosing of the ewe lambs with 15 mg/kg albendazole only achieved a 79.2% reduction in Dicrocoelium dendriticum egg count, 21 day post treatment. Thus, this report of dicrocoeliosis differs from the disease that occurs elsewhere, both in the severity and nature of its clinical signs, and in the response of the parasite to anthelmintic drug treatment. These differences could indicate the existence of a genetically divergent D. dendriticum population, which may have evolved within the unique and isolated biotope afforded by the machair on the island of Coll. Better understanding of these factors is a prerequisite for effective and sustainable disease control.

Opportunities and challenges for the application of microfluidic technologies in point-of-care veterinary diagnostics

There is a growing need for low-cost, rapid and reliable diagnostic results in veterinary medicine. Point-of-care (POC) tests have tremendous advantages over existing laboratory-based tests, due to their intrinsic low-cost and rapidity. A considerable number of POC tests are presently available, mostly in dipstick or lateral flow formats, allowing cost-effective and decentralised diagnosis of a wide range of infectious diseases and public health related threats. Although, extremely useful, these tests come with some limitations. Recent advances in the field of microfluidics have brought about new and exciting opportunities for human health diagnostics, and there is now great potential for these new technologies to be applied in the field of veterinary diagnostics. This review appraises currently available POC tests in veterinary medicine, taking into consideration their usefulness and limitations, whilst exploring possible applications for new and emerging technologies, in order to widen and improve the range of POC tests available.

Black-pigmented anaerobic bacteria associated with ovine periodontitis

Periodontitis is a polymicrobial infectious disease that causes occlusion change, tooth loss, difficulty in rumination, and premature culling of animals. This study aimed to detect species of the genera Porphyromonas and Prevotella present in the periodontal pocket of sheep with lesions deeper than 5mm (n=14) and in the gingival sulcus of animals considered periodontally healthy (n=20). The presence of microorganisms was evaluated by polymerase chain reaction (PCR) using specific primers for Porphyromonas asaccharolytica, Porphyromonas endodontalis, Porphyromonas gingivalis, Porphyromonas gulae, Prevotella buccae, Prevotella intermedia, Prevotella loescheii, Prevotella melaninogenica, Prevotella nigrescens, Prevotella oralis, and Prevotella tannerae. Prevalence and risk analysis were performed using Students t-test and Spearmans correlation. Among the Prevotella and Porphyromonas species detected in the periodontal lesions of sheep, P. melaninogenica (85.7%), P. buccae (64.3%), P. gingivalis (50%), and P. endodontalis (50%) were most prevalent. P. gingivalis (15%) and P. oralis (10%) prevailed in the gingival sulcus. P. gulae and P. tannerae were not detected in the 34 samples studied. Data evaluation by t-test verified that occurrence of P. asaccharolytica, P. endodontalis, P. gingivalis, P. buccae, P. intermedia, P. melalinogenica, and P. nigrescens correlated with sheep periodontitis. The findings of this study will be an important contribution to research on pathogenesis of sheep periodontitis and development of its control measures.

Treatment of sheep scab in the UK: preventing the spread of resistant mites

Sheep scab is a parasitic allergic dermatitis that affects sheep worldwide and is caused by the non-burrowing mite, Psoroptes ovis . It has serious welfare implications for animals affected (Fig 1) and a huge economic impact on the sheep farming industry. The disease is estimated to cost the UK sheep industry £8 million annually, with prevention accounting largely for this figure.1 FIG 1: An advanced case of sheep scab, where the lesions have spread across the entire body of the animal and there is evidence of poor body condition What you need to know As with any other …

Boer goats appear to lack a functional IgA and eosinophil response against natural nematode infection

Gastrointestinal nematode infection is one of the major diseases affecting small ruminants. Although some breeds of goats are quite resistant, many breeds of goats are relatively susceptible. This study used a combined parasitological, immunological, bioinformatic and statistical approach to examine the role of goat IgA and eosinophils in protection against Teladorsagia circumcincta. Molecular modelling suggested that the transmembrane domain of the high affinity IgA receptor was dysfunctional in goats. Statistical analyses failed to find any association in naturally infected goats between high IgA or eosinophil responses and low faecal egg counts. Together these results indicate that IgA and eosinophil responses against T. circumcincta are less effective in goats than sheep.

Global challenges for sustainable food production

Small ruminants are important globally in industrialised agriculture and subsistence farming systems. Small ruminant production is inherently inefficient, typically resulting in dependence upon subsidy support to protect economic returns, or failure to alleviate poverty in resource-deprived lower and middle income countries. Improving the efficiency of small ruminant production integrated with whole agricultural systems is vital to tackling global challenges of food and environmental security arising from population growth and climate change. an recent editorial in Veterinary Record described the immediate efficiency savings to be made through improvements in basic animal husbandry and health management (mcNeilly 2017). The editorial was accompanied by an image of transhumance sheep farming in southern India, in which sheep were being folded overnight on arable land, providing a sustainable source of manure. The image showed the impact of rapid urbanisation, whereby new buildings threaten a historically efficient method of food production by blocking daily access to water, while the affluence of their occupants creates an increased demand for sheep meat. The image depicted an individual recumbent and pyrexic ewe and another sick animal being caught for symptomatic treatment with generic flunixin, oxytetracycline and fluoroquinolone drugs. In all probability the animal health problem was caused by peste des petits ruminants (PPR). In October 2016, an announcement was made by the Food and agriculture Organization of the United Nations (FaO) and the World Organisation for animal Health (OIE) of an ambitious global plan to eradicate PPR by 2030 (VR, November 5, 2016, vol 179, p 447). However, the aforementioned scenario raises questions about how to instigate a rational disease control programme without access to veterinary diagnostic or vaccine distribution infrastructures. Consideration of PPR in the context of transhumance sheep farming raises concerns over responsible medicines use, biosecurity and the spread of other unrecognised production limiting diseases. Furthermore, the close contact between shepherds and their animals highlights the potential to improve human health standards through the control of zoonotic diseases. The theme of the 9th International Sheep Veterinary Congress will be opportunities for improvement in small ruminant production efficiency to sustainably meet the needs of the world’s growing human population for food. The complex agricultural, animal health, environmental, economic, political, cultural and behavioural dimensions surrounding food security challenges will be explored through plenary, keynote and proffered talks and posters, alongside a clinical strand focused on health challenges facing the UK sheep sector. There will be a series of structured interactive workshops aimed at sharing opinions and expertise to identify solutions to specific challenges, such as those outlined in the transhumance sheep case study, including a plenary workshop aimed at informing global control and eradication of PPR. The congress will conclude with a summary discussion, bringing together all of the aforementioned strands to format clear recommendations and guidelines to allow small ruminant health and production to meet the needs of the world’s growing human population. The congress will be held in Harrogate, from may 22 to 26, 2017. Details are available from www.sheepvetsoc.org.uk/ isvc2017.