Surveillance of Sarcoptic Mange in Iberian Ibexes (Capra pyrenaica) and Domestic Goats (Capra hircus) in Southern Spain

Sarcoptic mange is a highly contagious skin disease caused by Sarcoptes scabiei. Sera were collected from 411 Iberian ibexes, comprising 157 individuals with sarcoptic mange skin lesions and 254 clinically healthy animals, in 13 population nuclei across Andalusia (southern Spain) between 2015 and 2021. Skin samples from 88 of the 157 animals with mange-compatible lesions were also obtained. Moreover, 392 serum samples from domestic goats (Capra hircus) were collected in the same region and study period. Antibodies against S. scabiei were tested using an in-house indirect ELISA, while the presence of mites of S. scabiei was evaluated in the skin samples by potassium hydroxide digestion. Seropositivity was found in eight (3.1%) of the clinically healthy ibexes and in 104 (66.2%) of the animals with mange-compatible lesions. The presence of S. scabiei was confirmed in 57 (64.8%) out of the 88 skin samples analysed and anti-S. scabiei antibodies were found in 49 (86.0%) of these 57 mite-positive individuals. Seropositive animals were detected in population nuclei with previous records of sarcoptic mange, where S. scabiei mites were detected by potassium hydroxide digestion in individuals with sarcoptic mange-compatible external lesions. However, seropositivity was not observed in population nuclei that were historically free of this disease. None of the 392 domestic goats had antibodies against S. scabiei, suggesting an independent epidemiological cycle of sarcoptic mange in Iberian ibex populations in the study area, and a limited or null role of domestic goats in the transmission of the parasite to this wild species. Overall, our findings underscore the importance of maintaining and/or implementing integrated surveillance programs and control strategies in wildlife and livestock, to limit the risk of S. scabiei circulation in Iberian ibex populations.

Paratuberculosis, Animal Welfare and Biosecurity: A Survey in 33 Northern Italy Dairy Goat Farms

Paratuberculosis is a notable infectious disease of ruminants. Goats appear to be particularly susceptible. The survey aimed to investigate the spread of paratuberculosis in Italian goat farming and evaluate whether the presence of the disease could be influenced by welfare and biosecurity deficiencies. A serological survey for paratuberculosis in 33 dairy farms in northern Italy was conducted. Contextually, animal welfare and biosecurity were assessed, using a standardized protocol of 36 welfare indicators and 15 biosecurity indicators which assigns to each farm a welfare and biosecurity score from 0 (any application) to 100% (full application). An overall result of less than 60% was considered insufficient. Nineteen farms (58%) tested positive for paratuberculosis, with a mean intra-herd seroprevalence of 7.4%. Total welfare ranged from 39.56 to 90.7% (mean 68.64%). Biosecurity scores ranged from 10.04 to 90.01% (mean 57.57%). Eight farms (24%) showed poor welfare conditions (welfare score < 60%) and 19 (58%) an unsatisfactory biosecurity condition (biosecurity score < 60%). With respect to the explorative character of the study, an indicative association between seven welfare and biosecurity indicators and paratuberculosis seropositivity was identified. The presence of paratuberculosis in northern Italy dairy goat farms was confirmed. The welfare and biosecurity assessment protocol proved to be an accurate tool, capable of identifying critical points for managing health, welfare and productivity.

Antibiotic Use in Alpine Dairy Farms and Its Relation to Biosecurity and Animal Welfare

The quantification of antimicrobial usage (AMU) in food-producing animals can help identify AMU risk factors, thereby enhancing appropriate stewardship policies and strategies for a more rational use. AMU in a sample of 34 farms in the Province of Trento (north-eastern Italy) from 2018 to 2020 was expressed as defined daily doses for animals per population correction unit according to European Surveillance of Veterinary Antimicrobial Consumption guidelines (DDDvet) and according to Italian guidelines (DDDAit). A retrospective analysis was carried out to test the effects of several husbandry practices on AMU. Overall, the average AMU ranged between 6.5 DDDAit in 2018 and 5.2 DDDAit in 2020 (corresponding to 9 and 7 DDDvet, respectively), showing a significant trend of decrement (−21.3%). Usage of the highest priority critically important antimicrobials (HPCIA) was reduced by 83% from 2018 to 2020. Quarantine management, available space, water supply, animals’ cleanliness and somatic cell count had no significant association with AMU. Rather, farms with straw-bedded cubicles had lower AMU levels than those with mattresses and concrete floors (p < 0.05). In conclusion, this study evidenced a decrement in AMU, particularly regarding HPCIA, but only a few risk factors due to farm management.

Business intelligence tools to optimize the appropriateness of the diagnostic process for clinical and epidemiologic purposes in a multicenter veterinary pathology service

Laboratory tests provide essential support to the veterinary practitioner, and their use has grown exponentially. This growth is the result of several factors, such as the eradication of historical diseases, the occurrence of multifactorial diseases, and the obligation to control endemic and epidemic diseases. However, the introduction of novel techniques is counterbalanced by economic constraints, and the establishment of evidence- and consensus-based guidelines is essential to support the pathologist. Therefore, we developed standardized protocols, categorized by species, type of production, age, and syndrome at the Istituto Zooprofilattico Sperimentale delle Venezie (IZSVe), a multicenter institution for animal health and food safety. We have 72 protocols in use for livestock, poultry, and pets, categorized as, for example, "bovine enteric calf", "rabbit respiratory", "broiler articular". Each protocol consists of a panel of tests, divided into 'mandatory' and 'ancillary', to be selected by the pathologist in order to reach the final diagnosis. After autopsy, the case is categorized into a specific syndrome, subsequently referred to as a syndrome-specific panel of analyses. The activity of the laboratories is monitored through a web-based dynamic reporting system developed using a business intelligence product (QlikView) connected to the laboratory information management system (IZILAB). On a daily basis, reports become available at general, laboratory, and case levels, and are updated as needed. The reporting system highlights epidemiologic variations in the field and allows verification of compliance with the protocols within the organization. The diagnostic protocols are revised annually to increase system efficiency and to address stakeholder requests.

Echinococcus multilocularis and other cestodes in red foxes (Vulpes vulpes) of northeast Italy, 2012-2018

Background

Echinococcus multilocularis is a small tapeworm affecting wild and domestic carnivores and voles in a typical prey-predator life cycle. In Italy, there has been a focus of E. multilocularis since 1997 in the northern Italian Alps, later confirmed in red foxes collected from 2001 to 2005. In this study, we report the results of seven years of monitoring on E. multilocularis and other cestodes in foxes and describe the changes that occurred over time and among areas (eco-regions) showing different environmental and ecological features on a large scale.

Methods

Eggs of cestodes were isolated from feces of 2872 foxes with a sedimentation/filtration technique. The cestode species was determined through multiplex PCR, targeting and sequencing ND1 and 12S genes. Analyses were aimed to highlight variations among different eco-regions and trends in prevalence across the study years.

Results

Out of 2872 foxes, 217 (7.55%) samples resulted positive for cestode eggs at coproscopy, with differences of prevalence according to year, sampling area and age class. Eight species of cestodes were identified, with Taenia crassiceps (2.65%), Taenia polyacantha (1.98%) and E. multilocularis (1.04%) as the most represented. The other species, Mesocestoides litteratus, Taenia krabbei, T. serialis, T. taeniaeformis and Dipylidium caninum, accounted for < 1% altogether. Echinococcus multilocularis was identified in foxes from two out of six eco-regions, in 30 fecal samples, accounting for 1.04% within the cestode positives at coproscopy. All E. multilocularis isolates came from Bolzano province. Prevalence of cestodes, both collectively and for each of the three most represented species (T. crassiceps, T. polyacantha and E. multilocularis), varied based on the sampling year, and for E. multilocularis an apparent increasing trend across the last few years was evidenced.

Conclusions

Our study confirms the presence of a focus of E. multilocularis in red foxes of northeast Italy. Although this focus seems still spatially limited, given its persistence and apparent increasing prevalence through the years, we recommend research to be conducted in the future on the ecological factors that, on a smaller scale, allow this zoonotic species to persist. On the same scale, we recommend a health education campaign to inform on the measures to prevent this zoonosis, targeted at people living in the area, especially hunters, dog owners, forestry workers and other potentially exposed categories.

Two waves of canine distemper virus showing different spatio-temporal dynamics in Alpine wildlife (2006-2018)

Canine distemper virus (CDV) represents an important threat for both wild and domestic carnivores. Since 2006, the North-Eastern regions in Italy have been experiencing severe and widespread recurring outbreaks of CDV affecting the wild carnivore population. In this study we performed an extensive phylogeographic analysis of CDV strains belonging to the Wildlife-Europe genetic group identified between 2006 and 2018 in Veneto, Trentino Alto Adige and Friuli Venezia Giulia regions. Our analysis revealed that viruses from the first (2006-2009) and the second (2011-2018) epidemic wave cluster separately, suggesting the introduction of two distinct genetic variants. These two events were characterized by different diffusion rates and spatial distribution, thus suggesting the existence of a connection between infection spread and host population dynamics. We also report the first spillover event of this strain to a non-vaccinated dog in a rural area of Friuli Venezia Giulia. The increasing prevalence of the infection in wildlife population, the broad host range of CDV circulating in the Alpine wildlife and the first reported transmission of a wild-adapted strain to a domestic dog in this region raise concerns over the vulnerability of wildlife species and the exposure of our pets to new threatening strains. Understanding the dynamic of CDV epidemics will also improve preparedness for re-emerging diseases affecting carnivore species.

Sarcoptic Mange in Wild Caprinae of the Alps: Could Pathology Help in Filling the Gaps in Knowledge?

Sarcoptic mange represents the most severe disease for wild Caprinae individuals and populations in Europe, raising concerns for both conservation and management of these ungulates. To date, this disease has been investigated in different wild caprine species and under many different perspectives including diagnostics, epidemiology, impact on the host populations, and genetics of both hosts and parasite, with the aim to disentangle the host-Sarcoptes scabiei relationship. Notwithstanding, uncertainty remains and basic questions still need an answer. Among these are the effect of immune responses on mange severity at an individual level, the main drivers in host-parasite interactions for different clinical outcomes, and the role of the immune response in determining the shift from epidemic to endemic cycle. A deeper approach to the pathology of this disease seems therefore advisable, all the more reason considering that immune response to S. scabiei in wild Caprinae, generally classified as a hypersensitivity, remains poorly understood. In this paper, we reviewed the pathological features associated to sarcoptic mange in wildlife, exploring different kinds of hypersensitivity and outcomes, with the objective of highlighting the major drivers in the different responses to this disease at an individual level and proposing some key topics for future research, with a particular attention to Alps-dwelling wild caprines.

Evaluation of three enzyme-linked immunosorbent assays for sarcoptic mange diagnosis and assessment in the Iberian ibex, Capra pyrenaica

BACKGROUND

Sarcoptic mange is a contagious skin disease caused by the mite Sarcoptes scabiei, affecting different mammalian species worldwide including the Iberian ibex (Capra pyrenaica), in which mortalities over 90 % of the population have been reported. No efficient diagnostic methods are available for this disease, particularly when there are low mite numbers and mild or no clinical signs. In this study, three enzyme-linked immunosorbent assays (ELISA) developed for dog (ELISA A), Cantabrian chamois (Rupicapra pyrenaica parva) (ELISA B) and Alpine chamois (Rupicapra rupicapra) (ELISA C), were evaluated to detect specific antibodies (IgG) to sarcoptic mange in Iberian ibex sera.

METHODS

Serum samples from 131 Iberian ibexes (86 healthy and 45 scabietic) were collected from 2005 to 2012 in the Sierra Nevada Natural and National Parks (southern Spain). Based on visual inspection, ibexes were classified into one of three categories, namely healthy (without scabietic compatible lesions), mildly affected (skin lesions over less than 50 % of the body surface) and severely affected (skin lesions over more than 50 % of the body surface). The optimal cut-off point, specificity, sensitivity and the area under the curve (AUC) were calculated, and the agreement between tests was determined. Moreover, differences in the optical density (OD) related to scabies severity have been evaluated for the best test.

RESULTS

ELISA C showed better performance than the two other tests, reaching higher values of sensitivity (93.0 %) and specificity (93.5 %) against the visual estimation of the percentage of affected skin, chosen as the gold standard. Significantly higher concentrations of specific antibodies were observed with this test in the mildly and severely infested ibexes than in healthy ones.

CONCLUSIONS

Our results revealed that ELISA C was an optimal test to diagnose sarcoptic mange in the Iberian ibex. Further studies characterizing immune response during the course of the disease, including spontaneous or drug induced recovery, should follow in order to better understand sarcoptic mange in Iberian ibex populations.

The effects of antibiotic additions to extenders on fresh and frozen-thawed bull semen

Reproduction in dairy cows is based around the use of cryopreserved semen. Antibiotics are utilized to control bacterial contamination and growth in cryopreserved bull semen. The antibiotic resistance of some bacteria required the evaluation of new antibiotic combinations with a high level of antibacterial effectiveness and a negligible effect on spermatozoa. In this research, we studied the effect of the fluorinate carboxyquinolone ofloxacin and the combination of ceftiofur/tylosin on bull spermatozoa and in-field bacterial growth. In Experiment 1, the toxicity of different levels of ofloxacin and ceftiofur/tylosin was tested by the incubation of bull spermatozoa and the evaluation of sperm kinetic parameters, membranes and acrosome integrity after dilution, and at 60 and 120 min after incubation. The data reported in this study reveals that both antibiotic combinations, at all concentrations, seem to have a negligible effect on spermatozoa with respect to all of the parameters examined (p>0.05). Furthermore, progressive motility was significantly higher for sperm diluted with both antibiotic combinations compared with samples without antibiotics (p<0.01). In Experiment 2, the ability of ofloxacin or ceftiofur/tylosin to control bacterial growth during bovine semen cryopreservation was compared with the combination of gentamicin/tylosin/spectinomycin/lincomycin. A significant reduction in progressive motility was found in cooled semen with respect to all of the antibiotic treatments (p<0.05). However, the membrane integrity was found to significantly rise in frozen samples with, compared to samples without, antibiotics (p<0.05). In a bull, gentamicin, tylosin, spectinomycin, and lincomycin failed to control bacterial growth in the cryopreserved sample, while no such growth was found in samples extended with ceftiofur/tylosin or ofloxacin. In conclusion, both ceftiofur/tylosin and ofloxacin can be safely added to bull seminal extenders, and both can protect insemination doses from bacteria that are resistant to other antibiotic combinations.