Seroprevalence of six reproductive pathogens in European wild boar (Sus scrofa) from Spain: the effect on wild boar female reproductive performance

We studied the seroprevalence of six reproductive pathogens in Spanish hunter-harvested wild boar females. The sample was representative of the hunting harvest in the studied hunting estates. Mean antibody prevalences were: 60.6+/-0.06% for Aujeszky's disease virus (ADV), 56.6+/-0.09% for porcine parvovirus (PPV), 51.8+/-0.06% for porcine circovirus type 2 (PCV2), 29.7+/-0.09% for Brucella spp. and 36.3+/-0.1% for Toxoplasma gondii. We did not detect antibodies against porcine reproductive and respiratory syndrome virus (PRRSv). ADV seroprevalence was associated with PPV and PCV2 seroprevalence in Spanish wild boar females. Ovulation rate in the studied wild boar females was 4.41+/-0.16 (n=120), mean litter size was 3.91+/-0.16 (n=82) and the partial resorption index 0.92+/-0.17 (n=66). Ovulation rate and litter size were statistically associated with age. T. gondii seroprevalence was negatively related to ovulation rate and partial resorption index. Wild boars from managed fenced estates had antibodies against more pathogens than wild boars from open estates. Potential relations between management of wild boar populations and exposure of individuals to different reproductive pathogens are discussed.     

Seroprevalence of Anaplasma phagocytophilum in domestic and wild animals from central Italy

From January 2004 to July 2007, 2455 sera were collected from domestic and wild animals living in central Italy and tested by indirect immunofluorescence assay to detect antibodies against Anaplasma phagocytophilum. Considering sera with 1:40 antibody titers as positive, 336 (13.68%) animals scored positive. The percentages of seropositivity were: 46.26% (31/67) in fallow deer, 46.15% (24/52) in red deer, 16.89% (134/793) in horses, 16.78% (23/137) in cattle, 12.74% (13/102) in sheep, 8.76% (108/1232) in dogs, 4.16% (3/72) in goats. These data confirm the presence of A. phagocytophilum in wild ruminants and domestic animals, including pets, in central Italy.     

Diffuse multicentric large B-cell lymphoma invading the central nervous system in a European wild boar (Sus scrofa)

We describe a diffuse, multicentric, large B-cell lymphoma in a wild boar (Sus scrofa) involving the abdomen, head, and nose and invading the frontal leptomeninges. The tumor was predominantly composed of dense, basophilic, round-to-polygonal cells. Immunohistochemistry for CD79 and Ki-67 was positive in all masses.     

Mortality rates of wild boar Sus scrofa L. in central Europe

In many parts of Europe, wild boar Sus scrofa population increase, and thus, high densities and dispersal into new areas are accompanied by economic problems. Due to many factors like insufficient hunting strategies as well as underestimation of population densities and reproduction rates, harvest rates seem to be insufficient. Thus, we calculated mortality rates of several wild boar populations from 1998 to 2009, to show the efficiency of hunting within several studies distributed over eight European states. For calculating mortality rates, the daily probability of survival of radio telemetrically observed wild boar was analysed according to Mayfield (Wilson Bull 73:255-261, 1961) and with survival analysis in R for three age classes (0, 1, ≥2 years) and both sexes. The mortality rates of wild boar per annum, especially piglets, were comparably low (about 0.5 for piglets and similar for total population). About three third of all observed animals survived at least until the next period of reproduction. Mortality rates differed between some study areas, the sexes and age classes. The sex ratio of the shot piglets equals the sex ratio of captured piglets; there seems to be no sex-biased hunting in this age class, but in an older age. Shooting was the main cause of death; only very few animals died by natural causes, e.g. diseases. The comparative analysis of all studies reflects a low mortality of wild boar in highly productive populations. Our results certified the findings of several studies that predation, natural mortality, and road mortality have only small impact on wild boar populations, whereas especially, nutrition or hunting are mainly decisive. Assuming net reproduction rates of more than 200 % according to literature data, our results indicate that harvest rates are not sufficient at our study sites. In all our studies, mortality rates and, thus, harvest rates are less than the assumed total net reproduction. Especially, the harvest rate of piglets seems to be insufficient. Thus, the population will increase further. High reproduction has to be counteracted by regulating mainly the reproductive animals. For regulating a population, combined and effective hunting methods have to be conducted to harvest at least the net reproduction. Thus, we recommend higher hunting rates of piglets (80 % of the offspring should be harvested) and of adult females. Intensified hunting of piglets by drive hunts and at an early age as well as intensified single hunt on adult females might help regulating wild boar populations.     

Seroepidemiologic survey for Chlamydia suis in wild boar (Sus scrofa) populations in Italy

We used serology to estimate the prevalence of exposure to chlamydiae in Italian populations of wild boars (Sus scrofa). Sera from 173 hunter-killed wild boars harvested during the 2006-2009 hunting seasons in three Italian regions were tested for antibodies to Chlamydia suis, Chlamydophila pecorum, Chlamydophila abortus, and Chlamydophila psittaci by the microimmunofluorescence test. Antibody titers to chlamydiae ≥ 1:32 were detected in 110 of the 173 samples tested (63.6%). Specific reactivity could be assessed only in 44 sera with antibody titers to C. suis that were two- to threefold higher than antibody titers against the other chlamydial species; the other 66 sera had similar reactivity against all the chlamydia species tested. Antibody to C. suis was detected in sera from wild boar populations with rare or no known contact with domestic pigs. These results suggest that the wild boar could be a chlamydia reservoir and may acquire chlamydiae independent of contacts with the domestic pig.     

Epidemiological study of the intestinal helminths of wild boar (Sus scrofa) and mouflon (Ovis gmelini musimon) in central Italy

Since 1995 the population of wild ungulates increased significantly in the "Parco provinciale dei Monti Livornesi" (Livorno, Tuscany, Central Italy). We studied the intestinal macroparasites of two hosts, the wild boar (Sus scrofa) and the mouflon (Ovis gmelini musimon). In the case of wild boars we found a dominant parasite species, Globocephalus urosubulatus. For this parasite the frequency distribution of the number of parasites per host agrees with a negative binomial distribution. There is not a significant correlation between the age of the animals and the parasitosis. Furthermore the mean parasite burden of male and female wild boars does not differ significantly. In the case of mouflons we found a dominant parasite species Nematodirus filicollis with Trichuris ovis as codominant species.     

Genetic diversity in the European wild boar Sus scrofa: phylogeography,population structure and wild x domestic hybridization

• 1 Despite the vast literature on genetic variation in the domestic pig Sus scrofa, little is known about genetic differentiation in wild boar populations.
• 2 Here we present an up‐to‐date review of published data on the past and recent history of the European wild boar, its genetic diversity and the spatial distribution of genetic variation throughout the continent.
• 3 The phylogeography of the species seems to be shaped mostly by past large‐scale events (like postglacial recolonization) rather than by more recent human manipulation. Genetic differentiation is observed both on a continental and a regional scale, and non‐intuitive barriers to gene flow occur.
• 4 From an indirect estimate, hybridization between wild boar and domestic pigs is seemingly a minor source of genetic variation for wild boar populations, yet risks are still linked to the release of captive hybrids in some areas.
• 5 Finally, we present future perspectives concerning the development of powerful molecular tools and their possible application to the study and management of this species.

     

Tuberculous meningoencephalitis in a wild boar

Bovine tuberculosis, caused by Mycobacterium bovis, is a zoonotic disease that affects cattle and wildlife worldwide. These animal hosts can serve as reservoirs of infection, thus increasing the risk of human exposure and infection. Tuberculous meningoencephalitis complicating disseminated tuberculosis is described in a 7-mo-old wild boar (Sus scrofa).     

Udder preference in wild boar piglets

Competition to access the front teats in the domestic pig is strong during the first days of life, despite the fact that the number of piglets is fewer than the number of teats. Preference has been explained in terms of greater milk production (although it might also be the consequence rather than the cause), or reduced risk of crushing when the female lies down to begin a suckling session. Here, with the aim of determining whether one cause might be the body and reproductive modifications caused by artificial breeding, we analysed teat preferences of wild boar piglets in the wild. Fifty-one hunted females in lactation in the Western Iberian Peninsula were analysed. In contrast to domestic pigs, wild boar piglets showed a clear preference for rear udders. This preference was consistent for females of different ages and body characteristics, as well as for females hunted in different seasons. We suggest that the choice of rear udders in the wild boar may be related to the advantages of suckling at places offering higher protection from low temperatures and from predators, in contrast to domestic pigs, for which crushing is the main cause of mortality.     

Detection of porcine circovirus type 2 (PCV2) from wild boars in central Italy

The lesions observed in 16 wild boars, hunted in central Italy, led to the suspect that could be related to the infection by porcine circovirus type 2 (PCV2). The animals had macroscopic and histological lesions in the lungs, tonsils, and bronchial lymph nodes. PCV2 was detected in tissue samples by polymerase chain reaction (PCR) and immunohistochemistry and it was isolated in newborn swine kidney cell cultures. From the infected cell culture supernatant, the presence of PCV2 DNA was confirmed by real-time PCR whereas virus particles were observed by electron microscopy. These diagnostic data indicate that PCV2 can infect and cause disease in Sus scrofa subspecies other than domestic swine and it is present in the wild boar population in central Italy.     

Helminths of wild boar in Spain.

Forty-seven wild boars (Sus scrofa) collected from two areas in the province of Valencia (eastern Spain) were examined for digestive and respiratory helminth parasites. Helminth species and their prevalence were Taenia hydatigena cysticercus (19%), Ascarops strongylina (87%), Physocephalus sexalatus (6%), Ascaris suum (2%), Metastrongylus spp. (85%), Capillaria sp. (2%) and Macracanthorhynchus hirudinaceus (21%). Trichinella spp. were not found. Physocephalus sexalatus, A. suum, Capillaria sp. and M. hirudinaceus were found only in wild boars collected from one area (National Hunting Reserve of Cortes de Pallás). Macracanthorhynchus hirudinaceus did not occur in hogs < 1-yr-old, whereas the intensity of Metastrongylus spp. infection was the greatest in this age group.     

Microsatellite markers for identification and parentage analysis in the European wild boar (Sus scrofa)

ABSTRACT: BACKGROUND: The wild boar (Sus scrofa) is among the most widespread mammal species throughout the old world. Presently, studies concerning microsatellites in domestic pigs and wild boars have been carried out in order to investigate domestication, social behavior and general diversity patterns among either populations or breeds. The purpose of the current study is to develop a robust set of microsatellites markers for parentage analyses and individual identification. FINDINGS: A set of 14 previously reported microsatellites markers have been optimized and tested in three populations from Hungary, Portugal and Spain, in a total of 167 samples. The results indicate high probabilities of exclusion (0.99999), low probability of identity (2.0E-13 -- 2.5E-9) and a parentage assignment of 100%. CONCLUSIONS: Our results demonstrate that this set of markers is a useful and efficient tool for the individual identification and parentage assignment in wild boars.     

Cutaneous trematode Collyriclum faba in wild birds in the central European Carpathians

The occurrence of cutaneous trematode Collyriclum faba in wild birds was monitored in the central European Carpathians from 1996 to 2001. A total of 5,414 birds, representing 86 species, was examined. Collyriclum faba was found at 7 sites (5 in Slovakia, 1 in Poland, and 1 in the Czech Republic), and prevalences at the sites varied from 1 to 16%. Ten species of passerine birds were infected: blackcap (Sylvia atricapilla) (16 positive/622 tested, 2% prevalence), black redstart (Phoenicurus ochruros) (2/25, 8%), chaffinch (Fringilla coelebs) (7/113, 6%), common blackbird (Turdus merula) (1/143, 1%), common redstart (Phoenicurus phoenicurus) (1/30, 3%), dipper (Cinclus cinclus) (1/9, 11%), European robin (Erithacus rubecula) (103/838, 12%), goldcrest (Regulus regulus) (1/76, 1%), grey wagtail (Motacilla cinerea) (5/25, 20%), and yellowhammer (Emberiza citrinella) (1/73, 1%). Cutaneous cysts of C. faba were found in the birds from the end of May to mid-September, with the prevalence peaking in July and August. One to 21 cysts per bird were found. In black redstart, chaffinch, common redstart, European robin. and yellowhammer, cysts were most frequently observed on the legs, particularly in the crural region. In blackcap, common blackbird, dipper, and grey wagtail, almost all the cysts were found around the vent and on the abdomen. In goldcrest, the cyst was located above the coccygeal gland. Collyriclum faba is a common parasite in birds during summer in central European Carpathians. Collyriclum faba was observed for the first time in Poland. It appears that C. faba may be fatal for some of the bird hosts.     

The wild boar of Egypt]

The wild boar, Sus scrofa, is not a typical member of the Egyptian wild fauna, although it appears to have lived in the Nile Delta and other suitable regions in the north of the country. However, historic populations were probably of mixed origin, including feral domestic pigs. It is incorrect, as is sometimes still done, to include the wild boar in the iconographic bestiary of Ancient Egypt and assume that the domestic pigs of Ancient Egypt derive from local wild boars.     

Blood sampling by puncture in the cavernous sinus from hunted wild boar

A new method of sampling based on the extraction of blood from the cavernous sinus of the dura mater has been assessed in hunted wild boar. Blood from 139 animals was obtained by two different extraction methods: the harvesting from thoracic cavity (TC) and intracavernous venipuncture (IV). Sera obtained by the IV method had higher volume (mean 2.85 vs 1.85 ml), were less hemolytic (mean absorbance at 450 nm: 1.01 vs 2.41 nm). A higher number of samples and a higher proportion of sera collected by IV (90.6 %) compared to those obtained using the TC method (78.4 %), could be analyzed against Aujeszky’s disease using blocking ELISA. No statistically significant differences in seroprevalences between samples obtained using both extraction methods were observed. The results obtained indicate that the IV is an easy, fast, reliable, clean, and safe method to collect blood samples from hunted wild boar, proving a real alternative to the traditional collection method.