Veterinary Sciences — Open Access Journal

The anthelminthic efficacy of the crude extracts of Hypoestes forskaolii (Vahl) R.Br (Acanthaceae) against gastrointestinal nematodes (GIN) in sheep was investigated using the in vitro egg hatch inhibition assay. Faecal samples were collected from sheep with naturally occurring infection of GIN (Trichostrongylus spp., Chabertia ovina, Cooperia spp., Haemonchus contortus and Teladorsagia spp.). Crude leaf extracts of H. forskaolii was obtained using increasing polarity solvents: n-hexane, chloroform, chloroform:methanol 9:1, methanol. Thiabendazole (0.2 µg/mL and 0.5 µg/mL) was used as a positive control and untreated GIN eggs in deionised water served as the negative control. All the extracts exhibited a weak ovicidal activity against GIN (less than 50% of egg hatch). Noteworthy, the n-hexane extract showed a percentage of inhibition of egg hatching greater than other extracts inhibiting the 30.8% at the concentration of 1 mg/mL showing a dose-dependent effect on nematode eggs hatching. Further studies are needed to investigate the effects of extracts used and to evaluate the ovicidal effects of other extracts of H. forskaolii. Full article

Shiga toxin-producing Escherichia coli, like E. coli O157:H7, are important human and animal pathogens. Naturally-acquired E. coli O157:H7 infections occur in numerous species but, particularly, cattle have been identified as a significant reservoir for human cases. E. coli O157:H7 are isolated from a number of domestic and wild animals, including rodents that share a living space with cattle. These Shiga toxin-producing E. coli O157:H7 strains can be highly virulent in humans, but little is known about the sequelae of interspecies transfer. In a group of neonatal calves, we determined the differences in colonization patterns and lesions associated with infection using either a wildlife or bovine E. coli O157:H7 strain. In calves challenged with the wildlife E. coli O157:H7 strain, the large (descending) colon was solely colonized, which differed substantially from the calves inoculated with the bovine E. coli O157:H7 strain, where the spiral colon was the principal target of infection. This study also demonstrated that while both interspecies- and intraspecies-derived E. coli O157:H7 can infect young calves, the distribution and severity differs. Full article

Canine cancer rates are similar to humans, though the therapeutic options might be limited. Inducing a patient’s own immune system to have an anti-tumor response is an attractive approach to cancer therapy. In this safety study, autologous tumor vaccines produced specifically for each canine patient were combined with Advax™, a novel non-inflammatory immunomodulator and vaccine adjuvant and were tested for safety in a diverse range of patient presentations alone or in combination with other treatments. Canine patients had their tumor biopsied, debulked or resected and the tumor antigens were processed into an autologous vaccine formulated with Advax™ adjuvant with or without rhizavidin as an additional immune stimulant. Patients treated early in the trial received two intramuscular (IM) doses, 2 weeks apart. As the study progressed and no issues of safety were observed, the protocol was changed to weekly vaccinations for 4 weeks followed by monthly booster shots. Over the 150 I.M injections delivered to date, the vaccine was found to be very safe and no significant adverse reactions were observed. These results justify ongoing development and future controlled studies of this autologous vaccine approach. Full article

In recent years, Brucella suis has been sporadically reported in Italy in domestic and wild swine. Since standard serological tests can determine false positive results, the development of alternative tests with improved sensitivity and specificity is rather essential. We analyzed 1212 sera collected at slaughterhouse from healthy pigs belonging to 62 farms of North-Central Italy. Sera were tested by Rose Bengal Test, Complement Fixation Test, and subsequently by a Dot Blot (DB) and Western Blot assays (WB). Only one serum resulted positive to all tests, indicating that swine brucellosis has a very limited spread. DB and WB could represent a support to the available serological tests; however, further studies to validate these tests are needed. In the presence of reemerging diseases, a prompt and continuous monitoring design is necessary to acquire epidemiological information for the subsequent application of specific health emergency plans. Full article

The 9th Tick and Tick-borne Pathogen (TTP9) Conference was held in conjunction with the first Asia Pacific Rickettsia Conference (APRC1) in Cairns, Australia from 27 August until 1 September in 2017. This MDPI Veterinary Sciences Special Issue has been dedicated to selected veterinary science articles from the conference associated with the control of animal diseases in the context of ticks and tick-borne pathogens, including Rickettsia species. The articles presented in this Special Issue include novel developments for the future control of ticks and tick-borne diseases. This editorial describes the meeting content, the plenaries, the TTP awards, the MDPI Veterinary Science Special Issue articles, and serves as a legacy report for TTP9APRC1. Full article

Clinical audit is a quality improvement tool used to assess and improve the clinical services provided to patients. This is the first study to investigate the extent to which clinical audit is understood and utilised in farm animal veterinary practice. A cross-sectional study to collect experiences and attitudes of farm animal veterinary surgeons in the UK towards clinical audit was conducted using an online nationwide survey. The survey revealed that whilst just under three-quarters (n = 237/325; 73%) of responding veterinary surgeons had heard of clinical audit, nearly 50% (n = 148/301) had never been involved in a clinical audit of any species. The participants’ knowledge of what a clinical audit was varied substantially, with many respondents reporting not receiving training on clinical audit at the undergraduate or postgraduate level. Respondents that had participated in a clinical audit suggested that protected time away from clinical work was required for the process to be completed successfully. This novel study suggests that clinical audit is undertaken to some extent in farm animal practice and that practitioner perception is that it can bring benefits, but was felt that more resources and support were needed for it to be implemented successfully on a wider scale. Full article

In a world where climate change, vector expansion, human activity, and pathogen dispersal do not respect boundaries, the human–animal–pathogen interface has become less defined. Consequently, a One Health approach to disease surveillance and control has generated much interest across several disciplines. This systematic review evaluates current global research on the use of domestic dogs as sentinels for human infectious disease, and critically appraises how this may be applied within Canada. Results highlighted a bias in research from high- and middle-income-economy countries, with 35% of the studies describing data from the Latin America/Caribbean region, 25% from North America, and 11% from the European/Central Asia region. Bacteria were the most studied type of infectious agent, followed by protozoa, viruses, helminths, and fungi. Only six out of 142 studies described disease in Canada: four researched a variety of pathogens within Indigenous communities, one researched Borrelia burgdorferi in British Columbia, and one researched arboviruses in Quebec. Results from this review suggest that dogs could provide excellent sentinels for certain infectious-disease pathogens in Canada, yet are currently overlooked. Further research into the use of dog-sentinel surveillance is specifically recommended for California serogroup viruses, Chikungunya virus, West Nile virus, Lyme borreliosis, Rickettsia spp., Ehrlichia spp., and Dirofilaria immitis. Full article

Poultry-adapted H9N2 avian influenza viruses (AIVs) are commonly found in many countries in Asia, the Middle East, Africa, and Europe, and although classified as low pathogenic viruses, they are an economically important disease. Besides the importance of the disease in the poultry industry, some H9N2 AIVs are also known to be zoonotic. The disease in humans appears to cause primarily a mild upper respiratory disease, and doesn’t cause or only rarely causes the severe pneumonia often seen with other zoonotic AIVs like H5N1 or H7N9. Serologic studies in humans, particularly in occupationally exposed workers, show a large number of people with antibodies to H9N2, suggesting infection is commonly occurring. Of the four defined H9N2 poultry lineages, only two lineages, the G1 and the Y280 lineages, are associated with human infections. Almost all of the viruses from humans have a leucine at position 226 (H3 numbering) of the hemagglutinin associated with a higher affinity of binding with α2,6 sialic acid, the host cell receptor most commonly found on glycoproteins in the human upper respiratory tract. For unknown reasons there has also been a shift in recent years of poultry viruses in the G1 and Y280 lineages to also having leucine instead of glutamine, the amino acid found in most avian viruses, at position 226. The G1 and Y280 poultry lineages because of their known ability to infect humans, the high prevalence of the virus in poultry in endemic countries, the lack of antibody in most humans, and the shift of poultry viruses to more human-like receptor binding makes these viruses a human pandemic threat. Increased efforts for control of the virus, including through effective vaccine use in poultry, is warranted for both poultry and public health goals. Full article

Brucella infections in wildlife have gained a lot of interest from the scientific community and different stakeholders. These interests are often different and sometimes conflicting. As a result, different management perspectives and aims have been implemented (One Health, public health, veterinary public health, maintenance of a brucellosis free status in livestock, sustainable wildlife harvesting by hunters, wildlife and environmental health). When addressing Brucella infection in wildlife, the most important features of Brucella infection should be considered and the following questions need to be answered: (1) Is Brucella infection a result of a spillover from livestock or is it a sustainable infection in one or more wildlife host species? (2) Did the epidemiological situation of Brucella infection in wildlife change over time and, if so, what are the main drivers of change and does it impact the wildlife population dynamics? (3) Does Brucella infection in wildlife represent a reservoir of Brucella strains for livestock? (4) Is Brucella infection in wildlife of zoonotic concern? These questions point to the fundamental biological question of how animal (domestic and wildlife)/Brucella spp. partnerships are established. Will we be able to decipher an evolutionary trajectory through a livestock-to-wildlife “host jump”? Whole genome sequencing and new “omics” techniques will help in deciphering the molecular basis of Brucella host preference and open new avenues in brucellosis management aimed at preventing opportunities for Brucella host jumps. Full article

Opuntia ficus-indica (L.) Mill. is a xerophylous plant that originated in tropical and subtropical America. This plant is popularly known in Brazil as “palma forrageira” (cactus pear) and plays a fundamental role in animal nutrition, mainly in the Northeastern semi-arid region of the country. The plant has several uses since it presents bioactive compounds that confer biological and pharmacological properties. In this context, the cactus pear can also be considered a potential product to combat parasite infections. The objective of this study was to chemically characterize the O. ficus-indica hydroalcoholic extract (OFIEOH) and to determine its efficacy against gastrointestinal parasites using in vitro tests. Initially, the hydroalcoholic extract from cladode peels of O. ficus-indica was produced by maceration for 21 days. For the chemical characterization, colorimetric dosages were performed for carbohydrates, proteins, phenols and condensed tannins. Liquid chromatography coupled to mass spectrometry/electron spray ionization (LC-MS/ESI) was used to characterize the polyphenolic profile of the OFIEOH extract. Fifteen compounds were identified in the OFIEOH extract, such as methyl, glycosylated and aglycone quercetin derivatives and aglycone and glycosylated kaempferol derivatives. Tri-glycosylated methyl quercetin derivatives were the main compounds identified. In vitro egg hatch (EHT) and larval migration tests (LMT) were used in a range of concentrations of OFIEOH from 12.5 to 100 mg/mL for EHT and 12.5 to 200 mg/mL for LMT. In addition, the LMT was used to test ivermectin (IVM) (from 11.4 to 57.1 µM), associated with the inhibitory concentration of 50% (IC₅₀) for OFIEOH. The combination of OFIEOH (12.5 to 200 mg/mL) plus the IC₅₀ of IVM was also tested. The efficacy of OFIEOH alone varied from 19.33 to 90.0% using the EHT. The LMT revealed an efficacy of 5.78 to 77.26% for the extract. Both tests showed a concentration-dependence inhibitory effect. We found a drug-extract antagonistic neutralizing effect when doses of IVM were added to OFIEOH (maximum efficacy of 73.78%), while a positive additive effect was observed when OFIEOH was added to the IC₅₀ of IVM (IC₅₀ of 82.79 for OFIEOH alone against an IC₅₀ of 55.08 of OFIEOH + IVM). The data from this work indicate that OFIEOH alone may be considered as a suitable ecofriendly product to control gastrointestinal parasites of sheep, offering a more holistic approach to improve animal farming and welfare. The drug-extract interaction is also a promising therapeutic alternative, reducing the final dose to the host, with an optimum combination effect. Full article

Levels of Japanese cedar pollen (Cryptomeria japonica) have increased in Japan and cedar pollinosis caused by Japanese cedar pollen has been reported in dogs. Serum levels of immunoglobulin E (IgE) against Cry j 1 and Cry j 2 in dogs raised in institutes and treated at veterinary hospitals in Japan were thus investigated. A total of 71 sera obtained from two institutes and 87 sera obtained from veterinary hospitals in the Hyogo and Kanagawa Prefectures were analyzed in this study. Serum levels of IgE were measured using the enzyme-linked immunosorbent assay with commercial purified Cry j 1 and Cry j 2. IgE against Cry j 1 and Cry j 2 in sera obtained from the two institutes were detected, despite the dogs being bred in enclosed areas. Moreover, significant differences were noted in the serum levels of IgE against Cry j 1 and Cry j 2 between the two institutes. The number of samples showing Cry j 1 or Cry j 2 levels above the cut-off values was greater in the Kanagawa Prefecture than in the Hyogo Prefecture. In total, 14 dogs showed Cry j 1 and Cry j 2 levels greater than the cut-off values in the Hyogo Prefecture, and only three such dogs were seen in the Kanagawa Prefecture. A significant correlation between serum levels against both allergens was observed (r² = 0.6931, p < 0.0001). Full article

By using the egg hatch test (EHT), the larval development test (LDT) and the larval mortality/paralysis test (LMT), the in vitro anthelmintic activity on sheep gastrointestinal strongyles (GIS) of four plant-derived pure compounds, mangiferin (at 0.25%, 0.125% and 0.0625%), rutin (at 1%, 0.75%, 0.5%), quercetin (at 1%), and β-sitosterol (at 1%, 0.75%, 0.5%), was investigated. For comparison, untreated and treated (0.1% thiabendazole, 0.1% TBZ) controls were used. Six repetitions were made throughout the experiment. Data were statistically elaborated using the χ² test. The concentration able to inhibit the development of the 50% of L1s to L3s and causing the mortality of the 50% of L3s (EC50) was also calculated. L3s recovered from untreated Petri dishes were identified at the genus level. In EHT, all tested compounds at all concentrations significantly (p < 0.01) inhibited the hatch of the eggs when compared to the untreated controls, but none of them was as effective as 0.1% TBZ. In LDT, rutin (at 1%, 0.75% and 0.5%), mangiferin (at 0.25% and 0.125%), β-sitosterol (at 1%) and 0.1% TBZ completely prevented the larval development from L1 to L3 in respect to the untreated controls (p < 0.01). In LMT, all tested compounds significantly (p < 0.01) increased the death of L3s compared to the untreated controls, except for β-sitosterol at 0.5%. However, only rutin at all concentrations and 0.25% and 0.125% mangiferin were as effective as 0.1% TBZ. Haemonchus, Trichostrongylus, Chabertia and Teladorsagia/Ostertagia GIS genera, were identified. Full article

Estimates of dog population sizes are a prerequisite for delivering effective canine rabies control. However, dog population sizes are generally unknown in most rabies-endemic areas. Several approaches have been used to estimate dog populations but without rigorous evaluation. We compare post-vaccination transects, household surveys, and school-based surveys to determine which most precisely estimates dog population sizes. These methods were implemented across 28 districts in southeast Tanzania, in conjunction with mass dog vaccinations, covering a range of settings, livelihoods, and religious backgrounds. Transects were the most precise method, revealing highly variable patterns of dog ownership, with human/dog ratios ranging from 12.4:1 to 181.3:1 across districts. Both household and school-based surveys generated imprecise and, sometimes, inaccurate estimates, due to small sample sizes in relation to the heterogeneity in patterns of dog ownership. Transect data were subsequently used to develop a predictive model for estimating dog populations in districts lacking transect data. We predicted a dog population of 2,316,000 (95% CI 1,573,000–3,122,000) in Tanzania and an average human/dog ratio of 20.7:1. Our modelling approach has the potential to be applied to predicting dog population sizes in other areas where mass dog vaccinations are planned, given census and livelihood data. Furthermore, we recommend post-vaccination transects as a rapid and effective method to refine dog population estimates across large geographic areas and to guide dog vaccination programmes in settings with mostly free roaming dog populations. Full article

The genomes of influenza A viruses (IAVs) comprise eight negative-sense single-stranded RNA segments. In addition to the protein-coding region, each segment possesses 5′ and 3′ non-coding regions (NCR) that are important for transcription, replication and packaging. The NCRs contain both conserved and segment-specific sequences, and the impacts of variability in the NCRs are not completely understood. Full NCRs have been determined from some viruses, but a detailed analysis of potential variability in these regions among viruses from different host groups and locations has not been performed. To evaluate the degree of conservation in NCRs among different viruses, we sequenced the NCRs of IAVs isolated from different wild bird host groups (ducks, gulls and seabirds). We then extended our study to include NCRs available from the National Center for Biotechnology Information (NCBI) Influenza Virus Database, which allowed us to analyze a wider variety of host species and more HA and NA subtypes. We found that the amount of variability within the NCRs varies among segments, with the greatest variation found in the HA and NA and the least in the M and NS segments. Overall, variability in NCR sequences was correlated with the coding region phylogeny, suggesting vertical coevolution of the (coding sequence) CDS and NCR regions. Full article

Prolapsed nictitans gland (PNG) is an important ocular condition of dogs. Various surgical interventions have been described, but effective technique is currently considered to be a matter of personal clinician preference. The aim of this rapid review was to evaluate existing peer-reviewed evidence of effectiveness for surgical techniques and their subsequent effects on quantitative and clinical lacrimal outcomes for PNG. We performed a structured bibliographic search of CAB Abstracts, PubMed, and Medline using terms relevant to dogs, nictitans gland, and surgery on 13 September 2017. Included studies were assessed for study design, reporting characteristics, surgical techniques, and surgical and lacrimal outcomes. Fifteen of three hundred fifteen identified studies were eligible for inclusion. Seven different replacement techniques were identified, along with gland excision. All studies were observational or descriptive, with the exception of a single crossover trial. Outcomes reporting was heterogeneous and provided limited detail on lacrimal outcomes or on breed propensity for recurrence. Insufficient data precluded comparison of techniques for either surgical failure rates or lacrimal outcomes, although proportional meta-analysis yielded an overall failure rate of 3% (95% CI 1–7%) for the Morgan’s pocket procedure. Improved reporting of veterinary surgical studies will improve evidence appraisal and synthesis, as well as reduce potential sources of bias. Full article

The cattle tick Rhipicephalus microplus is one of the most important ectoparasites causing significant economic losses for the cattle industry. The major tool of control is reducing the number of ticks, applying acaricides in cattle. However, overuse has led to selection of resistant populations of R. microplus to most of these products, some even to more than one active principle. Thus, exploration for new molecules with acaricidal activity in R. microplus has become necessary. Triosephosphate isomerase (TIM) is an essential enzyme in R. microplus metabolism and could be an interesting target for the development of new methods for tick control. In this work, we screened 227 compounds, from our in-house chemo-library, against TIM from R. microplus. Four compounds (50, 98, 14, and 161) selectively inhibited this enzyme with IC₅₀ values between 25 and 50 μM. They were also able to diminish cellular viability of BME26 embryonic cells by more than 50% at 50 μM. A molecular docking study showed that the compounds bind in different regions of the protein; compound 14 interacts with the dimer interface. Furthermore, compound 14 affected the survival of partially engorged females, fed artificially, using the capillary technique. This molecule is simple, easy to produce, and important biological data—including toxicological information—are available for it. Our results imply a promising role for compound 14 as a prototype for development of a new acaricidal involving selective TIM inhibition. Full article

A two-year-old, intact female Scottish Terrier presented with one-and-a-half-year history of erosive and ulcerative lesions affecting the nasal planum. Clinical appearance, history, histopathology, and response to therapy were suggestive of a rare vasculopathy of the nasal planum that has been previously described in Scottish Terrier dogs. In previously published reports, medical treatments of the disease had failed, leading to euthanasia of five dogs, while a short-term follow-up was available for one case that was controlled with prednisolone and ciclosporin. The dog reported herein was successfully treated with medical therapy consisting initially of a combination of ciclosporin and prednisolone and endonasal stents applied over the first six months. Stents were inserted in order to prevent abnormal scarring and nostril stenosis. More than one and a half years after diagnosis, the dog is still being administered ciclosporin once daily, breathes normally, and has an optimal quality of life. Full article

Feline oral squamous cell carcinoma (OSCC) is a highly invasive form of cancer in cats. In human OSCC, cluster of differentiation 147 (CD147) contributes to inflammation and tumor invasiveness. CD147 is a potential therapeutic target, but the expression of CD147 in feline OSCC has not been examined. Immunohistochemistry was used to determine if cyclooxygenase 2 (COX-2) and CD147 expression in feline OSCC biopsies was coordinated. Tumor cells were more likely to express COX-2 (22/43 cases or 51%) compared to stroma (8/43 or 19%) and adjacent oral epithelium (9/31 cases or 29%) (p < 0.05). CD147 was also more likely to occur in tumor cells compared to stroma and adjacent mucosa, with 21/43 (49%) of cases having >50% tumor cells with mild or moderate CD147 expression, compared to 9/28 (32%) in adjacent epithelium and only 5/43 (12%) in adjacent stroma (p < 0.05). In feline OSCC cell lines (SCCF1, SCCF2, and SCCF3), CD147 gene expression was more consistently expressed compared to COX-2, which was 60-fold higher in SCCF2 cells compared to SCCF1 cells (p < 0.05). CD147 expression did not correlate with COX-2 expression and prostaglandin E2 (PGE2) secretion, indicating that they may be independently regulated. CD147 potentially represents a novel therapeutic target for the treatment of feline OSCC and further study of CD147 is warranted. Full article

Influenza viruses are among the major infectious disease threats of animal and human health. This review examines the recent discovery of novel influenza viruses in bats and cattle, the evolving complexity of influenza virus host range including the ability to cross species barriers and geographic boundaries, and implications to animal and human health. Full article