Assessing the risks of SARS-CoV-2 in wildlife

The novel coronavirus SARS-CoV-2 likely emerged from a wildlife source with transmission to humans followed by rapid geographic spread throughout the globe and severe impacts on both human health and the global economy. Since the onset of the pandemic, there have been many instances of human-to-animal transmission involving companion, farmed and zoo animals, and limited evidence for spread into free-living wildlife. The establishment of reservoirs of infection in wild animals would create significant challenges to infection control in humans and could pose a threat to the welfare and conservation status of wildlife. We discuss the potential for exposure, onward transmission and persistence of SARS-CoV-2 in an initial selection of wild mammals (bats, canids, felids, mustelids, great apes, rodents and cervids). Dynamic risk assessment and targeted surveillance are important tools for the early detection of infection in wildlife, and here we describe a framework for collating and synthesising emerging information to inform targeted surveillance for SARS-CoV-2 in wildlife. Surveillance efforts should be integrated with information from public and veterinary health initiatives to provide insights into the potential role of wild mammals in the epidemiology of SARS-CoV-2.

Factors associated with sepsis development in 606 Spanish adult patients with cellulitis

Background

Cellulitis, a frequent cause of admission of adult patients to medical wards, occasionally evolves to sepsis. In this study we analyze the factors related to sepsis development.

Methods

Prospective and observational study of 606 adult patients with cellulitis admitted to several Spanish hospitals. Comorbidities, microbiological, clinical, lab, diagnostic, and treatment data were analyzed. Sepsis was diagnosed according to the criteria of the 2016 International Sepsis Definitions Conference. Multiple logistic regression modelling was performed to determine the variables independently associated with sepsis development.

Results

Mean age was 63.4 years and 51.8% were men. Overall 65 (10.7%) patients developed sepsis, 7 (10.8%) of whom died, but only 4 (6.2%) due to cellulitis. Drawing of blood (P < 0.0001) or any (P < 0.0001) culture, and identification of the agent (P = 0.005) were more likely among patients with sepsis. These patients had also a longer duration of symptoms (P = 0.04), higher temperature (P = 0.03), more extensive cellulitis (P = 0.02), higher leukocyte (P < 0.0001) and neutrophil (P < 0.0001) counts, serum creatinine (P = 0.001), and CRP (P = 0.008) than patients without sepsis. Regarding therapy, patients with sepsis were more likely to undergo changes in the initial antimicrobial regimen (P < 0.0001), received more antimicrobials (P < 0.0001), received longer intravenous treatment (P = 0.03), and underwent surgery more commonly (P = 0.01) than patients without sepsis. Leukocyte counts (P = 0.002), serum creatinine (P = 0.003), drawing of blood cultures (P = 0.004), change of the initial antimicrobial regimen (P = 0.007) and length of cellulitis (P = 0.009) were independently associated with sepsis development in the multivariate analysis.

Conclusions

Increased blood leukocytes and serum creatinine, blood culture drawn, modification of the initial antimicrobial regimen, and maximum length of cellulitis were associated with sepsis in these patients.

Stability of clinically relevant depression symptoms in old-age across 11 cohorts: a multi-state study

AIMS

To study the temporal dynamics of depression symptom episodes in old-age and the related influence of risk factors.

METHODS

Data from 41 362 old adults (54.61% women; mean age = 75.30, SD = 6.20) from the Ageing Trajectories of Health - Longitudinal Opportunities and Synergies (ATHLOS) project were used. Depressive symptoms were followed over an 18-year period. A multi-state model, comprising three statuses (no depression, new clinically relevant episode of symptoms and episode persistence), was fitted. Multinomial regression was used to study the role of risk factors in status transition.

RESULTS

Almost 85% of participants showed no depression, but prevalence became lower over time (B = -0.25, P < 0.001). New episode point prevalence was over 5.30% with a significant probability of moving to persistence status (transition probability = 0.27). Episode persistence became evident in 9.86% of episode status transitions, with increasing rate over time (B = 0.54, P < 0.01). Loneliness was proven to be the strongest predictor of episode emergence (OR = 17.76) and persistence (OR = 5.93).

CONCLUSIONS

The course of depression tends to become chronic and unremitting in old-age. This study may help to plan interventions to tackle symptom escalation and risk factor influence.

Biotic and abiotic factors shape the microbiota of wild-caught populations of the arbovirus vector Culicoides imicola

Biting midges of the genus Culicoides are known vectors of arboviruses affecting human and animal health. However, little is known about Culicoides imicola microbiota and its influence on this insect's biology. In this study, the impact of biotic and abiotic factors on C. imicola microbiota was characterized using shotgun-metagenomic sequencing of whole-body DNA samples. Wild-caught C. imicola adult nulliparous females were sampled in two locations from Sicily, Italy. The climatic variables of temperature and soil moisture from both localities were recorded together with potential host bloodmeal sources. Shared core microbiome among C. imicola populations included Pseudomonas, Escherichia, Halomonas, Candidatus Zinderia, Propionibacterium, and Schizosaccharomyces. Specific and unique taxa were also found in C. imicola from each location, highlighting similarities and differences in microbiome composition between the two populations. DNA and protein identification showed differences in host preferences between the two populations, with Homo sapiens and Canis lupus familiaris L. being the preferred bloodmeal source in both locations. A principal component analysis showed that the combined effect of host preferences (H. sapiens) and local soil moisture factors shape the microbiome composition of wild-caught populations of C. imicola. These results contribute to characterizing the role of the microbiome in insect adaptation and its utility in predicting geographic expansion of Culicoides species with potential implications for the control of vector-borne diseases.

[Integral approach to the acute exacerbation of chronic obstructive pulmonary disease]

Chronic obstructive pulmonary disease is a set of clinical processes that have in common a chronic and progressive obstruction to airflow, with episodes of exacerbation. These exacerbations are more frequent and severe over time, deteriorating the lung function. The main cause of exacerbations is bacterial infection. There are multiple guidelines and documents that statement the management of this pathology. However, they focus primarily on the treatment during the stable phase. This document addresses the problem of acute exacerbation due to an infection from a multidisciplinary perspective, focusing on the integral approach to the process, and including etiology, microbiological studies, resistance to antimicrobials, risk stratification and initial empirical therapeutic management (antibiotic and concomitant). In addition, it includes an approach to more complex aspects such as the management of special populations (elderly and immunosuppressed) or therapeutic failure. Finally, more controversial topics such as prophylaxis of infection or palliative treatment are specifically discussed.

The Anopheles gambiae transcriptome - a turning point for malaria control

Mosquitoes are important vectors of several pathogens and thereby contribute to the spread of diseases, with social, economic and public health impacts. Amongst the approximately 450 species of Anopheles, about 60 are recognized as vectors of human malaria, the most important parasitic disease. In Africa, Anopheles gambiae is the main malaria vector mosquito. Current malaria control strategies are largely focused on drugs and vector control measures such as insecticides and bed-nets. Improvement of current, and the development of new, mosquito-targeted malaria control methods rely on a better understanding of mosquito vector biology. An organism's transcriptome is a reflection of its physiological state and transcriptomic analyses of different conditions that are relevant to mosquito vector competence can therefore yield important information. Transcriptomic analyses have contributed significant information on processes such as blood-feeding parasite-vector interaction, insecticide resistance, and tissue- and stage-specific gene regulation, thereby facilitating the path towards the development of new malaria control methods. Here, we discuss the main applications of transcriptomic analyses in An. gambiae that have led to a better understanding of mosquito vector competence.

Species diversity and spatial distribution of ixodid ticks on small ruminants in Greece

A cross sectional field study on the distribution of Ixodidae ticks was carried out over two consecutive tick seasons (2012 and 2013) in small ruminants (309 farms) located in mainland and five islands of Greece. A total of 2108 ticks (1199 females, 908 males, and 1 nymph) were collected from sheep and goats. Two species of Rhipicephalus, two of Ixodes, five of Hyalomma, three of Haemaphysalis, and one of Dermacentor were detected. The species with the widest distribution were Rhipicephalus sanguineus s.l. (64.8 %), R. bursa (25.9 %), and Dermacentor marginatus (4.1 %), whereas the least frequently collected species were Ixodes ricinus, I. gibbosus, Haemaphysalis parva, H. sulcata, H. punctata, Hyalomma marginatum, H. excavatum, H. dromedarii, H. rufipes, and H. impeltatum representing together less than 5.3 % of the collections. R. sanguineus s.l. was the predominant species, while D. marginatus and I. gibbosus were restricted to the northeastern Aegean Sea islands. This is the first survey on tick fauna from mainland and islands in Greece.

Strategies for new and improved vaccines against ticks and tick-borne diseases

Ticks infest a variety of animal species and transmit pathogens causing disease in both humans and animals worldwide. Tick-host-pathogen interactions have evolved through dynamic processes that accommodated the genetic traits of the hosts, pathogens transmitted and the vector tick species that mediate their development and survival. New approaches for tick control are dependent on defining molecular interactions between hosts, ticks and pathogens to allow for discovery of key molecules that could be tested in vaccines or new generation therapeutics for intervention of tick-pathogen cycles. Currently, tick vaccines constitute an effective and environmentally sound approach for the control of ticks and the transmission of the associated tick-borne diseases. New candidate protective antigens will most likely be identified by focusing on proteins with relevant biological function in the feeding, reproduction, development, immune response, subversion of host immunity of the tick vector and/or molecules vital for pathogen infection and transmission. This review addresses different approaches and strategies used for the discovery of protective antigens, including focusing on relevant tick biological functions and proteins, reverse genetics, vaccinomics and tick protein evolution and interactomics. New and improved tick vaccines will most likely contain multiple antigens to control tick infestations and pathogen infection and transmission.

Hemopoietic stem cell transplantation in thalassemia: a report from the European Society for Blood and Bone Marrow Transplantation Hemoglobinopathy Registry, 2000-2010

Allogeneic hemopoietic stem cell transplantation (HSCT) is the only method currently available to cure transfusion-dependent thalassemia major that has been widely used worldwide. To verify transplantation distribution, demography, activity, policies and outcomes inside the European Group for Blood and Marrow Transplantation (EBMT), we performed a retrospective non-interventional study, extracting data from the EBMT hemoglobinopathy prospective registry database. We included 1493 consecutive patients with thalassemia major transplanted between 1 January 2000 and 31 December 2010. In total, 1359 (91%) transplants were performed on patients <18 years old, 1061 were from a human leukocyte Ag-identical sibling donor. After a median observation time of 2 years, the 2-year overall survival (OS) and event-free survival (EFS; that is, thalassemia-free survival) were 88 ± 1% and 81 ± 1%, respectively. Transplantation from a human leukocyte Ag-identical sibling offered the best results, with OS and EFS of 91 ± 1% and 83 ± 1%, respectively. No significant differences in survival were reported between countries. The threshold age for optimal transplant outcomes was around 14 years, with an OS of 90-96% and an EFS of 83-93% when transplants were performed before this age. Allogeneic HSCT for thalassemia is a curative approach that is employed internationally and produces excellent results.

The genus Anaplasma: new challenges after reclassification

Summary The genus Anaplasmais one of four distinct genera in the family Anaplasmataceae, which are obligate intracellular pathogens vectored by ticks and found exclusively within parasitophorous vacuoles in the host cell cytoplasm. The 2001 reclassification of the order Rickettsiales expanded the genus Anaplasma, which previously contained pathogens that were host specific for ruminants (A. marginale, A. centrale and A. bovis), by adding A. phagocytophilum, a unification of three organisms previously classified as Ehrlichia (E. equi, E. phagocytophila and the unnamed agent of human granulocytic ehrlichiosis). Also included in the genus Anaplasma were A. bovis (formerly E. bovis), A. platys (formerly E. platys) and Aegyptianella pullorum. Despite the genomic relatedness of the regrouped organisms, many aspects of their biology are diverse, including their host specificity, host cell preferences, major surface proteins (MSPs) and tick vectors. This review focuses on the two most important pathogens: A. marginale, which causes bovine anaplasmosis, and A. phagocytophilum, the aetiologic agent of tick-borne fever in sheep and human granulocytic anaplasmosis, an emerging tick-borne disease of humans. For both pathogens, strain diversity is much greater than previously recognised. While MSPs were found to be useful in phylogenetic studies and strain identification, highly conserved MSPs were found to affect the specificity of serologic tests. Comparison of these two important pathogens highlights the challenges and insight derived from reclassification and molecular analysis, both of which have implications for the development and evaluation of diagnosis and control strategies.

Heterologous murine and bovine IVF using bottlenose dolphin (Tursiops truncatus) spermatozoa

Assisted reproductive technologies are of great importance for increasing the genetic diversity in captive animals. The use of bovine or murine oocytes in heterologous IVF provides advantages compared to homologous IVF in nondomestic animals, such as the accessibility to oocytes and the availability of well-developed in vitro maturation systems. The aim of this study was to determine the heterologous IVF parameters using cryopreserved dolphin spermatozoa and zona-intact bovine or murine oocytes and to examine the nuclear chromatin status of the dolphin spermatozoa. All the processes involved in the fertilization including embryo cleavage were observed by confocal microscopy and hybrid embryo formation was confirmed by polymerase chain reaction. Heterologous bovine IVF showed no polyspermy, lower percentages of pronuclear formation, and a lower cleavage rate compared to homologous IVF group (34.8% vs. 89.3%). Heterologous murine IVF showed a lower cleavage rate than homologous IVF (9.6% vs. 77.1%). With respect to dolphin sperm chromatin, it was more stable, i.e. more resistant to EDTA-SDS decondensation than the bovine sperm chromatin. This study revealed the stability of the dolphin sperm chromatin and the ability of the dolphin spermatozoa to penetrate zona-intact bovine and murine oocytes, leading to hybrid embryo formation.

The mental and subjective skin: Emotion, empathy, feelings and thermography

We applied thermography to investigate the cognitive neuropsychology of emotions, using it as a somatic marker of subjective experience during emotional tasks. We obtained results that showed significant correlations between changes in facial temperature and mental set. The main result was the change in the temperature of the nose, which tended to decrease with negative valence stimuli but to increase with positive emotions and arousal patterns. However, temperature change was identified not only in the nose, but also in the forehead, the oro-facial area, the cheeks and in the face taken as a whole. Nevertheless, thermic facial changes, mostly nasal temperature changes, correlated positively with participants' empathy scores and their performance. We found that temperature changes in the face may reveal maps of bodily sensations associated with different emotions and feelings like love.

Immunohistochemical characterisation of parasitic pneumonias of dolphins stranded in the Canary Islands

This is the first work that applies immunohistochemistry in the characterisation of the inflammatory infiltrate of verminous bronchopneumonia associated with lungworm parasites in stranded dolphins. Samples from three different species (Stenella coerulealba, Stenella frontalis and Delphinus delphis) stranded in the Canary Islands were used. The most common findings found in these animals varied from bronchitis to verminous bronchopneumonia with different degree of severity. The immunohistochemical study showed variable expressions of Lysozyme, MHC-II, iNOS and IgG. The main population presenting in the inflammatory infiltrates were CD3(+) lymphocytes. However, moderate number of Foxp3(+) lymphocytes was found in lymph nodes even though no Foxp3(+) cells were found in lung lesions in any of the samples analysed. This study revealed that lung lesions showed a chronic inflammatory infiltrate mainly composed by lymphocytes CD3(+). Deeper studies are needed in order to provide a more complete scope about the infiltrates involved in these types of lesions.

Effect of cryopreservation on the sperm DNA fragmentation dynamics of the bottlenose dolphin (Tursiops truncatus)

Sperm DNA fragmentation is one of the major causes of infertility; the sperm chromatin dispersion test (SCDt) evaluates this parameter and offers the advantage of species-specific validated protocol and ease of use under field conditions. The main purpose of this study was to evaluate sperm DNA fragmentation dynamics in both fresh and post-thaw bottlenose dolphin sperm using the SCDt following different cryopreservation protocols to gain new information about the post-thaw differential sperm DNA longevity in this species. Fresh and cryopreserved semen samples from five bottlenose dolphins were examined for sperm DNA fragmentation dynamics using the SCDt (Halomax(®)). Sperm DNA fragmentation was assessed immediately at collection and following cryopreservation (T0) and then after 0.5, 1, 4, 8, 24, 48 and 72 h incubation at 37°C. Serially collected ejaculates from four dolphins were frozen using different cryopreservation protocols in a TES-TRIS-fructose buffer (TTF), an egg-yolk-free vegetable lipid LP1 buffer (LP1) and human sperm preservation medium (HSPM). Fresh ejaculated spermatozoa initially showed low levels of DNA fragmentation for up to 48 h. Lower Sperm DNA fragmentation (SDF) was found in the second fresh ejaculate compared to the first when more than one sample was collected on the same day (p < 0.05); this difference was not apparent in any other seminal characteristic. While there was no difference observed in SDF between fresh and frozen-thawed sperm using the different cryopreservation protocols immediately after thawing (T0), frozen-thawed spermatozoa incubated at 37°C showed an increase in the rate of SDF after 24 h. Sperm frozen in the LP1(℗) buffer had higher levels (p < 0.05) of DNA fragmentation after 24- and 48-h incubation than those frozen in TTF or HSPM. No correlation was found between any seminal characteristic and DNA fragmentation in either fresh and/or frozen-thawed samples.

Effect of microsatellite selection on individual and population genetic inferences: an empirical study using cross-specific and species-specific amplifications

Although whole-genome sequencing is becoming more accessible and feasible for nonmodel organisms, microsatellites have remained the markers of choice for various population and conservation genetic studies. However, the criteria for choosing microsatellites are still controversial due to ascertainment bias that may be introduced into the genetic inference. An empirical study of red deer (Cervus elaphus) populations, in which cross-specific and species-specific microsatellites developed through pyrosequencing of enriched libraries, was performed for this study. Two different strategies were used to select the species-specific panels: randomly vs. highly polymorphic markers. The results suggest that reliable and accurate estimations of genetic diversity can be obtained using random microsatellites distributed throughout the genome. In addition, the results reinforce previous evidence that selecting the most polymorphic markers leads to an ascertainment bias in estimates of genetic diversity, when compared with randomly selected microsatellites. Analyses of population differentiation and clustering seem less influenced by the approach of microsatellite selection, whereas assigning individuals to populations might be affected by a random selection of a small number of microsatellites. Individual multilocus heterozygosity measures produced various discordant results, which in turn had impacts on the heterozygosity-fitness correlation test. Finally, we argue that picking the appropriate microsatellite set should primarily take into account the ecological and evolutionary questions studied. Selecting the most polymorphic markers will generally overestimate genetic diversity parameters, leading to misinterpretations of the real genetic diversity, which is particularly important in managed and threatened populations.

Demonstration of transplacental transmission of a human isolate of Anaplasma phagocytophilum in an experimentally infected sheep

Anaplasma phagocytophilum, first identified as a pathogen of sheep in Europe, more recently has been recognized as an emerging tick-borne pathogen of humans in the U.S. and Europe. Transmission of A. phagocytophilum is reported to be by ticks, primarily of the genus Ixodes. While mechanical and transplacental transmission of the type genus organism, A. marginale, occur in addition to tick transmission, these modes of transmission have not been considered for A. phagocytophilum. Recently, we developed a sheep model for studying host-tick-pathogen interactions of the human NY-18 A. phagocytophilum isolate. Sheep were susceptible to infection with this human isolate and served as a source of infection for I. scapularis ticks, but they did not display clinical signs of disease, and the pathogen was not apparent in stained blood smears. In the course of these experiments, one sheep unexpectedly gave birth to a lamb 5 weeks after being experimentally infected by inoculation with the pathogen propagated in HL-60 cells. The lamb was depressed and not feeding and was subsequently euthanized 18 h after birth. Tissues were collected at necropsy for microscopic examination and PCR to confirm A. phagocytophilum infection. At necropsy, the stomach contained colostrum, the spleen was moderately enlarged and thickened with conspicuous lymphoid follicles, and mesenteric lymph nodes were mildly enlarged and contained moderate infiltrates of eosinophils and neutrophils. Blood, spleen, heart, skin and cervical and mesenteric lymph nodes tested positive for A. phagocytophilum by PCR, and sequence analysis confirmed that the lamb was infected with the NY-18 isolate. Transplacental transmission should therefore be considered as a means of A. phagocytophilum transmission and may likely contribute to the epidemiology of tick-borne fever in sheep and other mammals, including humans.

Prevalence of tick-borne pathogens in adult Dermacentor spp. ticks from nine collection sites in France

The importance of Dermacentor spp. in the transmission of tick-borne pathogens is not well recognized in Europe. To investigate the role of Dermacentor spp. in the transmission of tick-borne pathogens, questing ticks were collected in 9 sites from southern to northwestern France (Camargue Delta to Eastern Brittany) where Dermacentor spp. exist and tick-borne diseases had occurred previously. Three tick species were collected during the spring and autumn of 2009. Collected ticks (both males and females) included D. marginatus (n=377), D. reticulatus (n=74), and I. ricinus (n=45). All ticks were analyzed by PCR or reverse line blot for the presence of pathogens' DNA. Pathogens analyzed were based on veterinarian reports and included Anaplasma phagocytophilum, Coxiella burnetii, Anaplasma marginale, Borrelia burgdorferi, Bartonella spp., Babesia spp., Theileria spp., and Francisella sp. Francisella tularensis was not detected in any of the analyzed ticks. In D. marginatus, infection prevalence for A. phagocytophilum (3%) was similar to that found in I. ricinus in Europe. Other pathogens present in D. marginatus included A. marginale (0.5%), Bartonella spp. (9%), C. burnetii (12%), F. philomiragia (1.3%), and Theileria annulata/Babesia bovis (0.3%), which were detected for the first time in France. Pathogens detected in D. reticulatus included A. marginale (1%), Bartonella spp. (12%), C. burnetii (16%), Borrelia spp. (1.5%), and F. philomiragia (19%). Pathogens detected in I. ricinus included A. phagocytophilum (41%), Bartonella spp. (9%), C. burnetii (18%), A. marginale (1%), Borrelia spp. (4.5%), and Babesia sp. (7%). This study represents the first epidemiological approach to characterize tick-borne pathogens infecting Dermacentor spp. in France and that may be transmitted by ticks from this genus. Further experiments using experimental infections and transmission may be now conducted to analyze vector competency of Dermacentor spp. for these pathogens and to validate such hypothesis.

154 EMBRYO RESPONSE OF SUPEROVULATED HOLSTEIN HEIFERS INSEMINATED WITH X-SORTED FROZEN SPERM

A study was conducted within a commercial embryo transfer program to assess the appropriateness of X-sorted semen in superovulated heifers. Commercial X-sorted semen frozen at a dose of 2 million sperm/straw and unsorted semen frozen at a dose of 20 to 30 million sperm/straw was used in donors according to the owner’s genetic criteria. One-hundred 15- to 18-month-old Holstein heifers were superovulated as follows: Animals received a CIDR device (Pfizer Animal Health, New York, NY, USA) for 13 days. At the time of CIDR insertion and 5 days later, heifers received 2 mL (0.15 mg) of d-cloprostenol (Veteglan, Laboratorios Calier, Spain). Gonadotropin-releasing hormone (GnRH), 200 mcg IM (Gonasyl, SIVA, Spain) was administered twice, 36 hours after the second prostaglandin (PGF) and 24 hours after CIDR removal. Superovulatory treatments with commercial FSH (Pluset, Laboratorios Calier) were initiated 36 hours after the first GnRH, with a total dose of 11.5 mL (575 IU), given twice daily in 10 daily decreasing-dose injections. Luteolysis was induced with 0.15 mg PGF given twice, 12 h before and at the time of CIDR removal. Heifers were randomly assigned to two groups for insemination in the uterine body: Group A (n = 31) heifers were inseminated with 5 straws of X-sorted semen in three inseminations (2 straws at 12 h, 2 straws at 18 h, and 1 straw at 24 h after the last GnRH); Group B (n = 69) heifers were inseminated twice with unsorted semen (one straw at each of 12 and 24 h after the last GnRH). A total of 614 embryos (153 in Group A and 461 in Group B) were collected and frozen. There were no significant differences between groups (Mann–Whitney rank sum test, SigmaStat, Systat Software Inc., San Jose, CA, USA) in the embryo production obtained (Table 1). Eighty-four embryos frozen with ethylene glycol were thawed and transferred; 34 from Group A, where all births were females and 50 from Group B with a 0.54 sex ratio. Pregnancy rates were 55 and 54% in Groups A and B, respectively. In conclusion, with the superovulation and AI schedule utilized in this experiment, the use of X-sorted semen in heifers can achieve reproductive outcomes similar to those obtained with unsexed semen, with the benefit of an increase in females offspring. Table 1.Mean number of recovered ova/embryos, transferable embryos, and unfertilized ova obtained in superovulated Holstein heifers inseminated with X-sorted (Group A) and unsorted (Group B) semen

170 ASSESSMENT OF FRESH AND FROZEN - THAWED BOTTLENOSE DOLPHIN (TURSIOPS TRUNCATUS) SPERM DNA FRAGMENTATION USING THE SPERM CHROMATIN DISPERSION TEST

There has been significant development over the last 20 years to improve genetic management of the captive bottlenose dolphin (Tursiops truncatus) by means of genome resource banking and assisted reproduction. Although standard semen parameters have been analysed in some detail, very little is known about sperm DNA fragmentation (SDF) in this species. The aim of this study was to develop a sperm chromatin dispersion test (SCDt) for the bottlenose dolphin to establish the baseline level of SDF immediately after ejaculation and cryopreservation and to determine the dynamic loss of sperm DNA quality after ex vivo handing and incubation in conditions that mimic the female reproductive tract. Semen from 8 bottlenose dolphins was collected by manual stimulation. Initial validation of the SCDt was conducted by means of in situ nick translation and neutral comet assay using a proven fertile male. To investigate the dynamic loss of sperm chromatin (rate of sDF loss), thawed sperm samples were incubated at 37.9°C for up to 48 h, and aliquots of spermatozoa were assessed after 1, 4, 8, 24, and 48 h. Dolphin sperm nuclei with fragmented DNA exhibited large halos of dispersed DNA fragments, whereas those with nonfragmented DNA displayed small halos of nondispersed DNA. A high correlation (r2 = 0.82; P ≤ 0.01) was found between the respective assessments of the SCDt and the neutral comet assay. All nucleoids resulting in a large halo of dispersed chromatin were intensely positive to in situ nick translation. The level of sDF fragmentation observed immediately after ejaculation in fresh and frozen samples was relatively low (1–5%). After comparing different ejaculates of the same individual, differences were found. Chromatin stability was high during the first 48 h of ejaculation or post-thawing and incubation. Evaluation of the sDF dynamics of fresh and frozen–thawed spermatozoa revealed no significant increase in the baseline level of sDF or in the relative increase of DNA damage after 48 h of incubation. Our data suggest that cryopreservation does not induce a dramatic increase in sperm chromatin damage. Interestingly, sperm samples derived from aged animals resulted in an increased rate of DNA loss, which was observed after 60 min post-incubation.

Factors driving the circulation and possible expansion of Crimean-Congo haemorrhagic fever virus in the western Palearctic

AIMS

To produce a spatial risk map regarding spread of Crimean-Congo haemorrhagic fever virus (CCHFV) in the western Palearctic by linking a process-driven model of the main tick vector, Hyalomma marginatum, to a Next Generation Matrix.

METHODS AND RESULTS

Process-driven model was composed of deterministic equations that simulate developmental and mortality rates of different tick stages by using temperature and atmospheric water vapour data. The model used climate data at 10-day intervals at a spatial resolution of 10 min over western Palearctic. The model estimated the basic reproduction number, R0, for CCHFV transmission by H. marginatum ticks and evaluated how changes in temperature and biological parameters may alter the geographical range of CCHFV. In particular, variation in the rate of transovarial transmission of CCHFV in the tick produced the greatest change in CCHFV circulation in the tick population. Parameters affecting the rates of tick bite, non-systemic transmission and efficiency of tick-to-tick transmission had little effect on R0. Temperature changes that affect tick development, survival and activity rates increased the suitable area for CCHFV transmission at higher latitudes in the western Palearctic.

CONCLUSIONS

Non-systemic transmission had little impact on virus transmission under all scenarios. In the area studied, increase of temperature has no impact on the routes of transmission of CCHFV. However, climate conditions favouring tick survival, which increase infected adult tick populations, together with large numbers of hosts for adults were predicted as the most likely scenario for the spread of the virus in the studied area.

SIGNIFICANCE AND IMPACT OF THE STUDY

The proposed framework is able to capture the dynamics and the relative contribution of the different routes (hosts, ticks) in the transmission and spread of an important pathogen affecting human health. The high contribution of the transovarial transmission route makes the process highly dependent upon suitable hosts for adult ticks, like large domestic and wild ungulates. Climate seems to have a very reduced effect on such spread.

Effects of culling Eurasian wild boar on the prevalence of Mycobacterium bovis and Aujeszky's disease virus

Worldwide, failure to eradicate a disease in livestock has sometimes been related to wildlife reservoirs of infection. We describe the effects of Eurasian wild boar (Sus scrofa) abundance reduction through increased culling on the prevalence of two chronic infectious diseases, tuberculosis (TB) and Aujeszky's disease (AD), in a region of South-central Spain (SCS). The two infections studied responded differently to an approximately 50% reduction of wild boar abundance. Wild boar TB prevalence remained stable in control sites, whereas it decreased by 21-48% in treatment sites. In one treatment site, the annual wild boar abundance was positively correlated with the annual percentage of skin test reactor cattle. In another treatment site, red deer (Cervus elaphus) M. bovis infection prevalence decreased after culling wild boar. No significant effect of wild boar culling on wild boar ADV seroprevalence was found. The reduction in wild boar TB was achieved despite no alternative M. bovis host being included in the culling strategy. We advocate that culling could become a part of integrated control strategies including habitat and game management changes and vaccination, contributing to increase their success likelihood, or reducing the total expenses.

Expression of heat shock proteins and subolesin affects stress responses, Anaplasma phagocytophilum infection and questing behaviour in the tick, Ixodes scapularis

We characterized the effects of subolesin and heat shock protein (HSP) expression on Ixodes scapularis Say (Acari: Ixodidae) stress responses to heat shock and feeding, questing behaviour and Anaplasma phagocytophilum (Rickettsiales: Anaplasmataceae) infection. Ticks and cultured tick cells were analysed before and after subolesin, hsp20 and hsp70 gene knock-down by RNA interference. The results of these studies confirm that HSPs are involved in the tick cell response to heat stress and that subolesin and HSPs are both involved in the tick response to blood-feeding stress and A. phagocytophilum infection. Subolesin and hsp20 are involved in the tick protective response to A. phagocytophilum infection and hsp70 expression may be manipulated by the pathogen to increase infectivity. Importantly, these results demonstrate that subolesin, hsp20 and hsp70 expression also affect tick questing behaviour. Overall, this research demonstrates a relationship between hsp and subolesin expression and tick stress responses to heat shock and blood feeding, A. phagocytophilum infection and questing behaviour, thereby extending our understanding of the tick-host-pathogen interface.

119 HETEROLOGOUS BOVINE IN VITRO FERTILIZATION USING CRYOPRESERVED BOTTLENOSE DOLPHIN SPERMATOZOA

Assisted reproductive technologies are of great importance for increasing genetic diversity in captive animals without displacing them. The development and improvement of these techniques require accurate methods to assess sperm function. The ability of the sperm to bind the zona pellucida and the formation of a male pronucleus have been shown to have a high predictive value for fertilization outcome. The use of zona-intact bovine in vitro–matured oocytes in heterologous fertilization with dolphin spermatozoa could provide valuable information on its fertilizing ability. The aim of the present study was to evaluate male pronuclear formation in zona-intact bovine oocytes after coincubation with frozen-thawed bottlenose dolphin spermatozoa. A total of 1546 immature cumulus oocytes complexes (COC) were obtained from bovine ovaries collected at slaughter. The COC were matured for 24 h in TCM-199 supplemented with 10 ng mL–1 of epidermal growth factor and 10% FCS. Matured COC were inseminated with frozen-thawed Bovi-pure (Nidacon International, Mölndal, Sweden) separated bovine (control) or dolphin spermatozoa. At 18, 20, 22, 24, 26 and 28 h post-insemination (hpi), half of the presumptive zygotes from each group were fixed and stained with Hoechst 33342 to examine sperm penetration, polyspermy and pronuclear formation and the remainder were cultured in synthetic oviduct fluid supplemented with 5% FCS for evaluating fertilization rates by cleavage on Days 2 and 4 (Day 0 = day of IVF). As expected, in the control a higher percentage of 2 pronuclear formation was observed at 18 hpi (74.5%), with a decrease at 20 and 22 hpi (57.4 and 43.2%, respectively) and was significantly lower (P ≤ 0.001) at 24 hpi (13.3%), reaching the lowest values at 26 and 28 hpi. However, in the heterologous group significantly less oocytes with both pronuclear formed (P ≤ 0.001) were observed at 18, 20 and 22 hpi (1.2, 3.4 and 3.0%, respectively) compared with 24, 26 and 28 hpi (22.5, 11.4 and 8.9%, respectively). No polyspermy was detected in oocytes coincubated with dolphin spermatozoa. Moreover, the cleavage rate at Day 2 and 4 in heterologous fertilization was 13.0 and 34.8%, respectively, whereas for the control it was 90.0%. In conclusion, these results indicate that dolphin spermatozoa can penetrate bovine oocytes and induce the block to polyspermy and the differences found regarding pronuclear formation times between the 2 species could be due to distinct sperm chromatin organisation or condensation. In conclusion, our preliminary results show that heterologous fertilization using bovine oocytes is useful for characterising the viability of dolphin thawed spermatozoa, which also could be helpful in performing a more complete sperm evaluation. Further studies are necessary to provide more consistent evidence of the efficiency of this test. The authors thank the staff at Zoo Aquarium Madrid for their dedicated work toward dolphin semen collection.

[Clinical usefulness of the reticulocyte hemoglobin equivalent in chronic hemodialysis patients]

BACKGROUND

Iron deficiency is the main cause of failure to respond to erythropoietin (EPO) in haemodialysis patients. Several laboratory tests to detect the deficiency, ferritin and transferrin saturation (TSat) are the most commonly used but its limitations in this patient population are necessary to find other parameters to improve the identification of iron-deficient state.

OBJECTIVE

To evaluate the ability of Reticulocyte Hemoglobin Equivalent (RET-He) to predict iron deficiency, taking as a reference standard to the increase of hemoglobin in response to iron intake.

MATERIALS AND METHODS

44 patients on chronic hemodialysis and fixed-dose EPO received 400 mg of intravenous iron. Were measured Hb, Ret-He, IRF, and ferritin prior to iron administration. After 20 to 30 days of completion of loading the patients were classified as responders if hemoglobin increased by at least 0.8 g / L and non-responders if this increase did not occur.

RESULT

25 patients were responders, the ROC curves analysis showed the Ret-He with the largest AUC of 0.862 similar to the AUC of 0.833 that showed the IST, but the first is more sensitive (72% CI 95%: 51-88% vs 52% 95% CI 31-72%) and similar specificity (94.7% CI 95%: 74-100% vs 100% 95% CI 82-100%). Ferritin AUC was 0.772 and finally the IRF AUC was 0.7. The Ret-He, to a cutoff of 29.5 pg was the best combination of sensitivity and specificity (72 and 94.7 respectively), and the sensitivity of the combination Ret-He/IST rose to 80% specificity 94.7%.

CONCLUSIONS

According to these results it could consider to Ret-He and the Ret-He/IST combination of clinical utility for the identification of the iron deficit in patients in chronic haemodialysis.

Immunization of rabbits with recombinant serine protease inhibitor reduces the performance of adult female Rhipicephalus microplus

Molecules secreted from the tick salivary gland modulate the vertebrate host immune response, thus representing potential targets for novel tick control measures. Tick salivary gland serine protease inhibitor (Serpin) is one such molecule that may facilitate tick feeding, blood meal digestion and pathogen transmission. The objective of this study was to determine the immunogenicity and protection of recombinant Rhipicephalus (Boophilus) microplus salivary gland Serpin (rSerpin) in rabbits. Rabbits were injected with rSerpin, adjuvant or phosphate-buffered saline (PBS) alone, and challenge infested with 500 R. microplus larvae that were allowed to continuously feed and moult through the adult stage. All immunized rabbits generated antibodies to rSerpin in the second week after immunization. Ticks fed on immunized rabbits resulted in 83% reduction in adult engorgement and 34% reduction in egg mass weight compared with the PBS control. These results indicated that this tick Serpin is immunogenic to rabbits, and suggested that this vaccine candidate antigen can confer protective immunity against cattle ticks in this experimental model.

Humoral immune response of dairy cattle immunized with rBm95 (KU-VAC1) derived from Thai Rhipicephalus microplus

Rhipicephalus (Boophilus) microplus is an important cause of economic losses in Thailand through direct effects of feeding on cattle and pathogen transmission. Current tick control methods rely on expensive chemical acaricides that result in environmental contamination, residues in food animal products and acaricide-resistant ticks. Anti-tick vaccines based on concealed antigens have shown promising results in the control of cattle tick. Thus, recombinant Bm95 (rBm95) from Thai R. microplus (KU-VAC1) was cloned and expressed to test as an anti-tick vaccine in Thailand. The objective of this study was to compare antibody responses induced by KU-VAC1 to that obtained after vaccination with Gavac that is based on the Bm86 homologue. Four groups of six cattle each were immunized with KU-VAC1, Gavac, adjuvant or phosphate-buffered saline, and boosted three times at 21-day intervals. Enzyme-linked-immunosorbent serologic assay were used to measure the humoral antibody responses specific to Thai rBm95. Cattle immunized with either KU-VAC1 or Gavac showed significantly greater antibody production than the controls. Antibody titres were detected after the first immunization and peaked after the seventh week. These results indicated that KU-VAC1 and Gavac are similarly immunogenic, and that further studies are warranted to compare performance parameters of ticks fed on immunized cattle.

Thrombophilic mutations: no association with thrombotic events in renal transplant recipients

Factor V Leiden and mutation of prothrombin gene G20210A have been associated with poor results in the early post-kidney transplantation period. Its long-term importance in stable patients has yet to be evaluated. We studied the prevalence of these inherited mutations and their relationship to thrombotic events in 82 Argentine renal transplant recipients with adequate long-term kidney function. In aggregate, 7.2% of patients were carriers of these mutations; however, their presence did not show any association with thrombotic events or renal function alterations. The routine evaluation for these mutations does not seem to be cost-effective in renal transplant patients.

Experimental infection of Eurasian wild boar with Mycobacterium avium subsp. avium

The Eurasian wild boar (Sus scrofa) is increasingly relevant as a host for several pathogenic mycobacteria. We aimed to characterize the first experimental Mycobacterium avium subsp. avium (MAA) infection in wild boar in order to describe the lesions and the immune response as compared to uninfected controls. Twelve 1-4-month-old wild boar piglets were housed in class III bio-containment facilities. Four concentrations of MAA suspension were used: 10, 10(2) and 10(4) mycobacteria (2 animals each, oropharyngeal route) and 2.5 x 10(6) mycobacteria (2 animals each by the oropharyngeal and nasal routes). No clinical signs were observed and pathology evidenced a low pathogenicity of this MAA strain for this particular host. Bacteriological and pathological evidence of successful infection after experimental inoculation was found for the group challenged with 2.5 x 10(6) mycobacteria. These four wild boar showed a positive IFN-gamma response to the avian PPD and the real-time RT-PCR data revealed that three genes, complement component C3, IFN-gamma and RANTES, were significantly down regulated in infected animals. These results were similar to those found in naturally and experimentally M. bovis-infected wild boar and may constitute biomarkers of mycobacterial infection in this species.

233 DIFFERENTIAL GENE EXPRESSION IN BOVINE BLASTOCYSTS AND ELONGATING CONCEPTUSES DERIVED IN VIVO OR IN VITRO

The majority of embryonic mortality in cattle occurs before maternal recognition of pregnancy at Day 16 postconception. In vitro-derived embryos exhibit a greater incidence of loss than their in vivo-derived counterparts. To better understand the causes of such embryonic loss, the aim of the current study was to compare transcript profiles of Days 7 and 13 bovine embryos derived in vitro or in vivo using the bovine Affymetrix microarray. We wanted to answer 3 questions: (1) what genes differ on Day 7 between blastocysts derived in vivo or in vitro, (2) what genes differ between Day 13 embryos derived from in vitro or in vivo embryos, and (3) what genes change between the blastocyst stage (Day 7) and the initiation of elongation (Day 13) and how are these temporal changes affected by the origin of the embryo. Day 7 bovine blastocysts were produced either in vitro by maturation, fertilization, and culture or in vivo by superovulation, AI, and nonsurgical embryo recovery. Half of the Day 7 blastocysts were snap frozen in liquid nitrogen in pools of 25 (microarray) or 10 (quantitative RT-PCR), and the other half were transferred in groups of 10 to synchronized heifers (10 recipients per group) ipsilateral to the corpus luteum and recovered on Day 13 by flushing the uterus after slaughter. Day 13 conceptuses were snap frozen individually. Three replicate pools of 25 Day 7 blastocysts and 5 Day 13 conceptuses were used for microarray analysis. Of the 24 128 probe-sets on the array, approximately 9500 genes were actively expressed in Days 7 and 13 embryos, irrespective of source. In Day 7 blastocysts, 50 genes were found to be differentially expressed (≥ 1.5-fold; P ≤ 0.05), of which 19 were up-regulated and 31 down-regulated in the in vivo compared with in vitro embryos. In Day 13 conceptuses, 288 genes were found to be differentially expressed (≥1.5-fold; P ≤ 0.05), of which 133 were up-regulated and 155 down-regulated in the in vivo compared with in vitro embryos. The comparison between Days 7 and 13 embryos revealed significant temporal changes in transcript profile, with 1806 and 909 transcripts differentially expressed in in vitro and in vivo-derived embryos, respectively. Across the 3 array comparisons between Days 7 and 13 embryos, 444 genes were consistently exclusively present in in vivo embryos, whereas 1341 were exclusively present in in vitro embryos. Array validation was done by quantitative RT-PCR analysis of fatty acid desaturase 1 (FADS1), cytochrome P450, family 51, subfamily A, polypeptide I (CYP51), and hyaluronan binding protein 2 (HABP2) genes. In conclusion, these results indicate that the origin of the blastocyst can have a significant effect on the transcript profile of the conceptus at the initiation of elongation and might be associated with the likelihood of embryo survival/loss subsequently. Further hierarchical clustering analysis and quantitative RT-PCR data will address the functional roles for certain known genes and novel candidate genes related to embryonic mortality. This work was supported by a grant (AGL2006-05616) from the Spanish Ministry of Science and Technology.

408 HOLSTEIN DONORS RESPONSE USING OR NOT USING ESTRADIOL 17-β IN THE SUPEROVULATORY TREATMENT

Because of new regulations banning the use of estradiol in the European Union and other countries, the present study was designed to determine the efficacy of an alternative to the use of estradiol 17-β in superovulation of Holstein cows and heifers. A total of 61 lactating cows and 49 heifers (15-18 months old) were divided into 2 groups: Group A (32 cows and 22 heifers) and Group B (29 cows and 27 heifers). Animals in Group A received a CIDR device (Pfizer, Madrid, Spain) for 13 days. At the same time of CIDR insertion and 5 days later, all animals received 2 mL (0.15 mg) of d-cloprostenol (PGF; Veteglan®, Calier, Spain). Gonadotropin-releasing hormone (0.5 mg of gonadorelin; Fertagyl®, Schering-Plough, Carbajosa de la Sagrada, Spain) was administered twice, 36 h after the second PGF and 24 h after CIDR removal. Superovulation treatments were initiated 36 h after the first GnRH, with a total dose of 15 mL (750 IU) of FSH (Pluset®, Calier, Spain) for cows and 11.5 mL (575 IU) for heifers, given in 10 twice-daily injections that decreased in dose. Luteolysis was induced with 0.15 mg of PGF given twice, 12 h before and also at the time of CIDR removal. Animals in Group B received a CIDR device for 7 days. Twenty-four hours after CIDR insertion, all animals received 100 mg of progesterone (Smithkline, Tres Cantos, Spain) and 5 mg of estradiol 17-β (Sigma, St. Louis, MO, USA). Beginning on Day 5, animals were superovulated with similar doses of FSH to those used in Group A. Luteolysis was induced with 0.15 mg of PGF given twice, 12 h before CIDR removal and also at the time of removal. Gonadotropin-releasing hormone (0.5 mg) was administered at the time of AI. Animals from both groups were inseminated with frozen-thawed semen at 12 and 24 h after the onset of standing estrus. Embryos were recovered nonsurgically 7 days later. A total of 299 frozen-thawed embryos (Freeze Control® CL5500, Bioniche, Belleville, Ontario, Canada) from both groups were transferred in synchronized Holstein heifers. Pregnancy was confirmed by rectal palpation on Day 40 to 45 of gestation. Data were analyzed by two-way ANOVA and results are shown in the table. No significant differences were found between cows and heifers, nor was there a difference between groups. These results showed that the previous superovulatory treatment using progesterone and estradiol can be successfully replaced with the treatment protocol described herein. Table 1.Mean number of recovered ova/embryos, transferable embryos, and pregnancy rates after embryo transfer (ET) in Holstein cows and heifers superovulated with 2 treatment protocols

First data on Eurasian wild boar response to oral immunization with BCG and challenge with a Mycobacterium bovis field strain

The Eurasian wild boar (Sus scrofa) is considered a reservoir for bovine tuberculosis (bTB) caused by Mycobacterium bovis and closely related members of the Mycobacterium tuberculosis complex in south-central Spain. The vaccination of wildlife with BCG offers an alternative to culling and to movement restriction for the control of bTB among wildlife reservoirs. In this study, we hypothesized that oral BCG immunization of wild boar would affect the expression of immunoregulatory genes and confer protection against M. bovis. Three groups were used to describe the infection, pathological findings and gene expression profiles in wild boar: BCG-vaccinated and M. bovis-challenged (vaccinated challenged group; N=6), non-vaccinated and M. bovis-challenged (non-vaccinated challenged group; N=4), and non-vaccinated and mock-infected (control group; N=2) animals. M. bovis was isolated from 50% (3/6) and 75% (3/4) of vaccinated challenged and non-vaccinated challenged animals, respectively. All four wild boar from the non-vaccinated challenged group developed bTB-compatible lesions 114 days after challenge. In contrast, only 50% of vaccinated challenged wild boar developed lesions. The PBMC mRNA levels of IL4, RANTES, C3, IFN-gamma and methylmalonyl-CoA mutase (MUT) were analyzed at several days post-vaccination (dpi). When vaccinated challenged animals were compared to controls, all five genes were significantly upregulated at the time of M. bovis infection at 186dpi but IFN-gamma levels were also upregulated at 11 and 46dpi. The C3 and MUT mRNA levels were higher at 46dpi, and 11 and 186dpi, respectively, in vaccinated protected wild boar when compared to non-vaccinated challenged animals. At the end of the experiment (300dpi), the mRNA levels of selected genes were lower in non-vaccinated challenged animals when compared to control wild boar. Exposing wild boar to a dose of 10(4)cfu of M. bovis by the oropharyngeal route is an adequate protocol to produce an infection model in this species. Our results suggested that oral BCG immunization of wild boar results in the upregulation of immunoregulatory genes that may be associated with protective response to M. bovis infection in this species. More studies on vaccine efficacy, delivery, and safety will be needed to confirm if oral vaccination with BCG could be used in bTB control programs for reducing M. bovis infection and clinical disease in wild boar.

Characterization of anaplasma infections in Sicily, Italy

This study aimed to characterize infection with Anaplasma marginale, A. phagocytophilum, A. ovis, and A. platys in humans, animals, and ticks in Sicily, Italy, during 2003-2006. Serologic (competitive ELISA [cELISA]) and indirect immunofluorescence antibody [IFA]; N= 1990) and DNA (polymerase chain reaction [PCR]; N= 2788) tests were conducted on horse, donkey, cattle, sheep, goat, pig, dog, cat, roe deer, wild boar, human, and tick samples. The results reported herein suggested that in Sicily cattle are a major reservoir for A. marginale, dogs for A. platys, and sheep and goats for A. ovis. Domestic animals, such as cattle, horses, donkeys, sheep, dogs, and cats, may serve as reservoir for A. phagocytophilum, but different strains may infect ruminants and humans. All Anaplasma spp. characterized in Sicily had some distinctive genotypes for this region. Low genetic diversity was observed in A. ovis and A. platys, whereas A. marginale and A. phagocytophilum strains showed high genetic diversity. These results expanded our knowledge about the prevalence of Anaplasma spp. in Sicily and provided information to understand the epidemiology of these infections and implement measures to diagnose, treat, and control transmission to humans and animals in this region.

Influence of methylmalonyl-CoA mutase alleles on resistance to bovine tuberculosis in the European wild boar (Sus scrofa)

An association study was carried out to examine the influence of methylmalonyl-CoA mutase (MUT) polymorphisms on the susceptibility of a well-studied wild boar population from southern Spain to develop bovine tuberculosis (bTB). To this end, we examined polymorphisms at a closely linked dinucleotide microsatellite flanking exon 2 of the MUT gene in 37 wild boars with bTB and 36 non-infected individuals. The microsatellite showed low polymorphism in the studied population, with only three alleles (MUTm-A, MUTm-B and MUTm-C) found, in contrast to the 11 alleles previously reported for domestic pigs. Our case-control study showed that the MUTm-B allele was associated with disease in a dominant pattern (odds ratio = 3.36; 95% CI = 1.05-10.72; P = 0.04), while the MUTm AA genotype appeared to have a protective effect against bTB infection (odds ratio = 4.33; 95% CI = 1.20-14.96; P = 0.02). Interestingly, infected wild boars heterozygous for MUTm AB are at an advantage (11-fold) to contain the systemic spread of the disease when compared to other genotypes, implying that a balanced polymorphism may be present in the population. These results strengthen previous observations regarding the importance of the MUT gene on bTB resistance in wild boars and indicate that polymorphisms at this locus will influence the risk of acquiring and maintaining bTB in the studied population.