Gastrointestinal parasites in an isolated Norwegian population of wild red deer (Cervus elaphus)

Background

Thirteen red deer (Cervus elaphus), culled from the isolated population at the Mongstad Oil Refinery, Norway, were investigated for gastrointestinal helminths. These animals, enclosed by the refinery fence, do not have contact with other ruminants and have a high population density considering the available browsing area (1 km²) within the refinery site (3 km²). The population was estimated to be 110-130 at the time of culling.

Results

The helminth fauna among these sampled red deer was enumerated and species were identified based on morphology. Ostertagia leptospicularis/O. kolchida was detected in 83% [CI 55 - 95%], Spiculopteragia spiculoptera/S. mathevossiani in 92% [CI 65 - 99%] and Trichostrongylus axei in 42%, [CI 19 - 68%] of the abomasa examined. Characterisation of the intestinal parasite fauna revealed Capillaria bovis, Cooperia oncophora, Oesophagostomum venulosum, Trichuris globulosa and tapeworm fragments (presumed anoplocephalids) in seven individuals. Only one calf had an infection with more than one intestinal helminth (tapeworm fragment and Trichuris globulosa). The remaining six deer had single species intestinal infections.No significant age related trends were seen, with the exception of higher intensity of infection of T. axei in yearlings relative to other age classes. Assessment of abomasal parasite burden and body condition revealed no significant trends. In calves, statistically non-significant correlation was seen between increased parasite burden and decreased slaughter weight, whilst the opposite was seen in adults with the heaviest adults exhibiting the higher burdens. Given the small sample size the trends that were seen need further investigation. The parasite burden was aggregated with three adult red deer harbouring 75% of the total abomasal parasite count.

Conclusion

This isolated population was parasitised by a reduced subset of gastrointestinal nematodes typical of this cervid across an extensive geographic range in Eurasia. The intensity and abundance of abomasal nematodes was higher in this isolated population than reported in similar studies of red deer populations across Europe.     

Mycoplasma Ovipneumoniae Demonstrated in Icelandic Sheep

For at least thirty years chronic pneumonia of suckling lambs has occurred in many sheep flocks in the north-eastern part of Iceland, Thingeyjarsýsla. Owing to the retarded growth rate of affected lambs, the farmers named it “kregda” which means “the poor eater”. A similar syndrome has also been observed in some areas of South Iceland (Gíslason 1963).     

Lack of cross-protection against Mycoplasma haemofelis infection and signs of enhancement in “Candidatus Mycoplasma turicensis”-recovered cats

“Mycoplasma haemofelis” and “Candidatus Mycoplasma turicensis” are feline hemoplasmas that induce hemolytic anemia. Protection from homologous re-challenge was recently demonstrated in cats recovered from primary infection. Here, we determined if cats recovered from “Cand. M. turicensis” infection were protected against infections with the more pathogenic M. haemofelis. Ten specified pathogen-free cats were exposed to M. haemofelis. Five of the ten cats had recovered from “Cand. M. turicensis” bacteremia (group A), and five cats were naïve controls (group B). No cross-protection was observed. By contrast, the “Cand. M. turicensis”-recovered cats displayed faster M. haemofelis infection onset (earlier PCR-positive and anemic) than the controls. No “Cand. M. turicensis” was detected in any cat. M. haemofelis shedding was observed in saliva, feces and urine. In both groups, evidence of a Th1 response was observed (high IFN-γ, low IL-4), but IL-10 levels were also high. In group A, total, CD4+ and CD8+ T cells increased within days after M. haemofelis exposure. At times of maximal bacteremia, macrocytic hypochromic anemia, neutropenia, monocytosis and a decrease in leukocyte, eosinophil, and lymphocyte counts and subsets thereof (B- and T-cells, CD4+, CD8+ and CD4+CD25+ cells) were particularly significant in group A. Moreover, an increase in protein concentrations, hypoalbuminemia and a polyclonal hypergammaglobulinemia were observed. Five of ten M. haemofelis-infected cats subsequently cleared bacteremia without antibiotic treatment. In conclusion, the study suggests that a previous hemoplasma infection, even when the cat has ostensibly recovered, may influence subsequent infections, lead to an enhancement phenomenon and other differences in infection kinetics.

Electronic supplementary material

The online version of this article (doi:10.1186/s13567-015-0240-x) contains supplementary material, which is available to authorized users.     

Glutathione Peroxidase Activity in Porcine Blood

Determination of the seleno-enzyme glutathione peroxidase (GSH-Px) in blood from Danish Landrace pigs was done using a quantitative, spectrophotometric method and a simple “spot test”. A close correlation between the net reaction rate measured spectrophotometrically (Δ A/min.) and time for defluores-cence (minutes) was obtained (r² = 0.72—0.77, P < 0.0005). From these results the factors used for a conversion of defluorescence time to u/g hemoglobin were evaluated. The results further showed that the “spot test” can be used as a screening method for detection of subnormal GSH-Px levels in pigs.While red cell GSH-Px seems independent of the sex, an elevation of both plasma and red cell GSH-Px was found with increasing age of pigs. The normal range of red cell GSH-Px activity was wide, contrasting the small variations observed in the individual pig. Some evidence that porcine red cell GSH-Px is under genetical control was found and discussed in relation to the possible use of GSH-Px as an indicator of the pig''s selenium status.     

Risk of tuberculosis cattle herd breakdowns in Ireland: effects of badger culling effort,density and historic large-scale interventions

Bovine tuberculosis (bTB) continues to be a problem in cattle herds in Ireland and Britain. It has been suggested that failure to eradicate this disease is related to the presence of a wildlife reservoir (the badger). A large-scale project was undertaken in the Republic of Ireland during 1997–2002 to assess whether badger removal could contribute to reducing risk of cattle herd breakdowns in four areas. During the period of that “four area” study, there was a significant decrease in risk in intensively culled (removal) areas relative to reference areas. In the present study, we revisit these areas to assess if there were any residual area effects of this former intervention a decade on (2007–2012). Over the study period there was an overall declining trend in bTB breakdown risk to cattle herds. Cattle herds within former removal areas experienced significantly reduced risk of breakdown relative to herds within former reference areas or herds within non-treatment areas (OR: 0.53; P < 0.001). Increased herd breakdown risk was associated with increasing herd size (OR: 1.92-2.03; P < 0.001) and herd bTB history (OR: 2.25-2.40; P < 0.001). There was increased risk of herd breakdowns in areas with higher badger densities, but this association was only significant early in the study (PD*YEAR interaction; P < 0.001). Badgers were culled in areas with higher cattle bTB risk (targeted culling). Risk tended to decline with cumulative culling effort only in three counties, but increased in the fourth (Donegal). Culling badgers is not seen as a viable long-term strategy. However, mixed policy options with biosecurity and badger vaccination, may help in managing cattle breakdown risk.

Electronic supplementary material

The online version of this article (doi:10.1186/s13567-014-0109-4) contains supplementary material, which is available to authorized users.     

Behavioral and stress responses to feeding time in pregnant sows under limit-fed regime

We investigated the effect of feeding time on behavior and stress responses in pregnant sows under isocaloric conditions. Twenty-four sows were balanced for parity and randomly assigned to 1 of 3 feeding times. Corn–soybean meal-based diet was fed once at: 0730 (Control, T1), 1130 (T2), and 1530 hours (T3). On average, sows received 7,062 kcal ME/d from 2.20 kg of diet formulated to contain SID Lys/ME of 1.71 g/Mcal. The study was conducted for 28 d (21 d acclimation to the feeding regime and 7 d data collection). Saliva samples were collected every 2 hr for 12 hr in stalls on day 52 of pregnancy. Behavior data were collected 24 hr for 7 d from day 53 of gestating by affixing a remote insights ear tag to each sow. Each sow had 120,960 data points categorized into: “Active,” “Feed,” or “Dormant”. Due to housing constraint, all sows were housed in individual stalls in the same barn presenting a potential limitation of the study. Data were analyzed using PROC MIXED and GLIMMIX procedures of SAS 9.4 for cortisol and behavior data, respectively. Sow was the experimental unit. The area under the curve (AUC) is quantitative evaluation of response as threshold varies over all possible values. A 12-hr cortisol total AUC for sows fed once daily at 1130 hours was reduced relative to sow group fed at 1530 hours (P = 0.046) but similar compared with the control sows (P = 0. 323). The control sows (0730 hours) had reduced total (P < 0.001) and feeding (P = 0.001) activity AUCs relative to sows on 1130 hours but did not differ compared with sows on 1530 hours feeding schedules (P > 0.100). Sows on 1130 hours feeding schedule had greater feed anticipatory activity, 24-hr total activity count, total (P < 0.001) and feeding (P < 0.001) activity AUC compared with sows fed daily at 1530 hours. In conclusion, feeding pregnant sows earlier in the morning (0730 hours) appears to minimize sows’ behavior but similar cortisol response. Sows on 1130 hours feeding schedule had greater activities but reduced cortisol concentration, suggesting that elevated sow activity might not necessarily indicate activation of hypothalamic–pituitary–adrenal axis.     

Behavioral and performance response associated with administration of intravenous flunixin meglumine or oral meloxicam immediately prior to surgical castration in bull calves

The objective of this study was to determine the effects of flunixin meglumine or meloxicam on behavioral response and performance characteristics associated with surgical castration in crossbred bulls. Intact male Bos taurus calves (n = 252; averaging 176 kg) were randomly allocated into one of three treatment groups within pen: control (CON), flunixin meglumine (FLU; 2.2 mg/kg intravenous injection), or meloxicam (MEL; 2.0 mg/kg per os). The individual animal was the experimental unit. Calves were individually weighed on days 0 and 14 of the trial to evaluate performance outcomes. On study day 0, treatments were administered, according to their random allocation, immediately prior to surgical castration using the Henderson tool method. Visual analog scale (VAS) assessment and categorical attitude score (CAS) were collected on days −1, 0 (6 h post-castration), 1, 2, 3, and 4 in the study. The VAS was assigned using a 100 mm horizontal line with “normal” labeled at one end of the line and “moribund” at the other end of the horizontal line. The masked observer assigned a mark on the horizontal line based upon the observed severity of pain exhibited by that individual animal. The CAS was assigned by the same observer using five different categories with a score of 0 being “normal”. Average daily gain tended (P = 0.09) to be associated with the treatment group, and MEL had a greater (P = 0.04) average daily gain through day 14 compared with CON. A significant (P < 0.01) treatment by day interaction was indicated for VAS score, and MEL had lower VAS scores on days 0, 1, 2, and 3 post-castration compared with CON; FLU had lower VAS scores on days 0 and 1 compared with CON. A significant treatment by day interaction was not present (P = 0.25) for CAS. The FLU had lesser percent CAS ≥1 (17.5%; P = 0.05) compared with CON (29.4%); MEL has lesser percent CAS ≥1 observations (14.9%; P = 0.01) compared with CON. The median VAS increased as CAS was more severe. Results indicated MEL and FLU calves temporally improved behavioral responses following surgical castration with positive numerical trends for a 14 d average daily gain (ADG). The VAS system appeared to be an effective method of subjective evaluation of pain in beef calves in this study. Route of administration, duration of therapy, and low relative cost make oral meloxicam a reasonable analgesic treatment in calves when administered at the time of surgical castration.     

Age changes in extramural digestive glands of sheep and rabbits in the postembryonic period

Background:The study of the peculiarities of the anatomy of sheep and rabbits’ digestive systems is an important way to improve the efficiency of these animals’ breeding.Aim:The aim of the presented research was to study structural changes of such digestive glands as the liver and the pancreas which occur in the process of ontogenesis in sheep and rabbits.Methods:Sheep of the “Kazakh fat-tailed semi-coarse-wooled” breed (n = 8) raised in the “Sayan” private peasant agriculture and rabbits of the “Grey Giant” breed (n = 8), raised on the mini rabbit farm of the Agriculture Faculty of Shakarim University were used in the research.Two experimental animal groups were formed (of sheep, “Kazakh fat-tailed semi-coarse-wooled” breed, n = 8; rabbits, “Grey Giant” breed, n = 8). The liver and pancreas’ ontogenesis development has been studied in these animals.Results:The study presents a holistic view of the macro-microscopic structure of the liver and the pancreas of animals in crucial age periods, stages, and phases of postembryonic ontogenesis (by the example of sheep and rabbits). The authors have traced age stages of adaptive change and structural-functional change of stromal-parenchymatous structures of the liver in sheep and rabbits taking into account stages and crucial phases of development.Conclusion:Development of the liver and the pancreas are characterized by discontinuous growth in the process of postnatal ontogenesis. A crucially important period is the first months after birth, during which the weight and functionality of these organs grow rapidly.     

Pampas deer (Ozotoceros bezoarticus) courtship and mating behavior

Background

Pampas deer, Ozotoceros bezoarticus (Linnaeus 1758), is a South American grazing deer categorized as "near threatened". However, knowledge about pampas deer behavior including courtship and mating is scarce and incomplete. The aim of this study was to characterize the courtship and mating behavior of the pampas deer (Ozotoceros bezoarticus), an endangered species from South America.

Methods

We performed focal observations of 5 males allocated at the Estación de Cría de Fauna Autóctona Cerro Pan de Azúcar, Uruguay, 4 times a day from 5 to 20 minutes each time on a daily basis from February to May. During that period we recorded all courtship and mating behaviors, as well as quantified the frequency of the specific behaviors shown. As mating were rarely observed, we recorded that behavior when it was observed in the context of other studies performed in the same population during the following 2 years.

Results

During the observation period we recorded 928 courtships and 5 mating periods. In addition, we recorded 10 more matings performed during other studies, totaling 15. The duration of each mating calculated from the 15 recordings was 3.9 ± 0.4 s, and the total period of female receptivity (from first to last mating acceptance) was 8.2 ± 1.1 min. Main observed courtship behaviors in males were “chase” and “ostentation”, while the most observed close to mating were “chinning”, “raised head” and “anogenital sniffing”. The most observed behaviors in females during the mating period were “vulva exhibition” and “move away”.

Conclusion

This is the first detailed report in pampas deer mating behavior. Estrus lasted only 8 min accepting only 3 short copulations per estrus. However, female behavior during courtship can be characterized as highly proceptive.     

A KCNJ10 mutation previously identified in the Russell group of terriers also occurs in Smooth-Haired Fox Terriers with hereditary ataxia and in related breeds

Background

Hereditary ataxias with similar phenotypes were reported in the Smooth-Haired Fox Terrier, the Jack Russell Terrier and the Parson Russell Terrier. However, segregation analyses showed differing inheritance modes in these breeds. Recently, molecular genetic studies on the Russell group of terriers found independent mutations in KCNJ10 and CAPN1, each associated with a specific clinical subtype of inherited ataxia. The aim of this study was to clarify whether or not Smooth-Haired Fox Terriers with hereditary ataxia and dogs of other related breeds harbor either of the same mutations. A sub goal was to update the results of KCNJ10 genotyping in Russell group terriers.

Findings

Three Smooth-Haired Fox Terriers with hereditary ataxia and two Toy Fox Terriers with a similar phenotype were all homozygous for the KCNJ10 mutation. The same mutation was also found in a heterozygous state in clinically unaffected Tenterfield Terriers (n = 5) and, in agreement with previous studies, in Jack Russell Terriers, Parson Russell Terriers, and Russell Terriers.

Conclusions

A KCNJ10 mutation, previously associated with an autosomal recessive spinocerebellar ataxia in Jack Russell Terriers, Parson Russell Terriers, and Russell Terriers segregates in at least three more breeds descended from British hunting terriers. Ataxic members of two of these breeds, the Smooth-Haired Fox Terrier and the Toy Fox Terrier, were homozygous for the mutation, strengthening the likelihood that this genetic defect is indeed the causative mutation for the disease known as “hereditary ataxia” in Fox Terriers and “spinocerebellar ataxia with myokymia, seizures or both” in the Russell group of terriers.     

Effects of Maropitant Citrate or Acepromazine on the Incidence of Adverse Events Associated with Hydromorphone Premedication in Dogs

Background

Vomiting is a common complication associated with the use of hydromorphine for pre‐emptive analgesia in dogs. The ideal anti‐emetic protocol for prevention of this complication has not been established.

Hypothesis

Maropitant administered concurrently or before hydromorphone would reduce the incidence of vomiting, signs of nausea, ptyalism, and increased panting compared to administration of acepromazine or a 0.9% saline control.

Animals

Sixty mixed‐breed female dogs scheduled for ovariohysterectomy.

Methods

Randomized, blinded, placebo‐controlled experimental study. Dogs were assigned to 4 experimental groups with 15 dogs per group. All groups received 0.2 mg/kg of hydromorphone IM. Group “Control” received 0.1 mL/kg saline SC 30–45 minutes before hydromorphone, group “Marop1” received 1 mg/kg maropitant SC 30–45 minutes before hydromorphone, group “Ace” received 0.02 mg/kg IM acepromazine 30–45 minutes before hydromorphone, and group “Marop2” received 1 mg/kg SC maropitant concurrently with hydromorphone. A trained and blinded observer documented adverse events from the time hydromorphone was administered until the time dogs were induced for surgery.

Results

Marop1 had significantly less vomiting (0%) compared to Control (87%; P < .01) and Ace (53%; P < .01). Marop2 had significantly less vomiting (27%) compared to Control (P < .01). Marop1 had significantly greater incidence of ptyalism (73%) compared to Ace (P < .01; 20%). Ace showed significantly less panting (33%) compared to Marop2 (93%; P < .01).

Conclusions and Clinical Importance

In healthy dogs, maropitant citrate administered before hydromorphone significantly decreases the incidence of vomiting in dogs but does not improve signs of nausea, ptyalism, or increased panting.     

Freeze-resistant Trichinella (Trichinella nativa) Established on the Scandinavian Peninsula

Until the 1970’s, Trichinella spiralis (Owen 1835) was considered the only species within the genus Trichinella. Then T. pseudospiralis (Garkavi 1972) was classified as a separate species on the basis of morphological and biological features. The remaining morphologically homogenous “T. spiralis-group” has been split into 4 different species (or subspecies) on the basis of their biological and biochemical characteristics; T. nativa (Britov & Boev 1972), T. nelsoni (Britov & Boev 1972), T. spiralis sensu stricto and T. britovi (Pozio et al. 1992).     

Sensitive diagnosis of bovine tuberculosis in a farmed cervid herd with use of an MPB70 protein fluorescence polarization assay

After histopathological examination of a lesion found in a herd member returned a diagnosis of mycobacteriosis, a farmed herd (n = 47) of elk (Cervus elaphus nelsoni) and red deer (C. elaphus elaphus) was investigated for bovine tuberculosis with a battery of antemortem and postmortem diagnostic tests. Every animal was tested with the mid-cervical tuberculin skin test; all 47 had negative results. All of the 16 adult animals and 15 of the 31 calves (approximately 2-years-old) were blood-tested with a lymphocyte stimulation test (LST) and a fluorescence polarization assay (FPA), which detects antibody to the MPB70 protein antigen. At necropsy of the 31 blood-tested animals, tissues were harvested for histopathological examination and culture of mycobacteria. Mycobacterium bovis was isolated from 16 of the 31 animals, and a scotochromogen was also isolated from 1 of the 16 whose tissues yielded M. bovis. Each of these 16 animals, 15 of which were calves, also received a histopathological diagnosis of mycobacteriosis. Other species of mycobacteria, including those belonging to the M. avium and M. terrae complexes, were isolated from an additional 7 animals. The FPA was scored “positive” or “suspect” for 16 animals, 13 (81%) of which were culture-positive for M. bovis. The other 3 animals that were culture-positive for M. bovis had negative FPA results. Of the 3 FPA-positive or FPA-suspect animals that were culture-negative, 2 were suspected to have mycobacteriosis on the basis of the histopathological examination. The 7 animals from which Mycobacterium species other than M. bovis were cultured were all FPA-negative. The only animal with positive LST results was also FPA-positive and culture-positive for M. bovis. The M. bovis isolates had an identical spoligotype pattern, with an octal code of 664073777777600. This is the first report of the isolation and identification of this strain type in Canada.     

Nitrofuran Production Efficiency In Chickens

Two nitrofuran feed additives, 0.011% nihydrazone and a combination of 0.0055% nitrofurazone and 0.0008% furazolidone, improved weight gains and feed conversions in chickens with “air sac infection.” Both nitrofurans caused a significant reduction in the total chickens condemned at the dressing plant from this disease, but nihydrazone gave the best results.

Nihydrazone^*, a new nitrofuran feed additive for chickens, was found by Wolfgang et al. (1) to be effective against coccidiosis due to Eimeria tenella and E. necatrix. In chickens nihydrazone was shown by Edgar et al. (2) to result in fewer chickens condemned from “air sac infection” than with any other drug used. Rosenberg et al. (3) found nihydrazone caused significant reduction in condemnations due to this disease. Cosgrove (4) showed that nihydrazone prevented an outbreak of cecal coccidiosis, reduced the incidence of “air sac infection,” improved weight gains, feed conversions and livability. Bierer (5) found nihydrazone active against fowl typhoid.

Harwood et al. (6) reported bifuran^** effective against E. tenella and E. necatrix coccidiosis and it has been used commercially for this purpose. Bierer (5) (7) found Bifuran^*** active in prevention of pullorum disease and fowl typhoid in chicks.

The mode of action of nihydrazone and nitrofurazone against E. tenella coccidiosis was shown by Johnson and Van Ryzin (8).

This production efficiency study was undertaken to evaluate nihydrazone and bifuran in the presence of “air sac infection” and concomitant diseases under field conditions. Camden (9) states that the only satisfactory test of a drug is the performance it gives under field conditions.

Nihydrazone (1) (5) and Bifuran (5) (6) have both antibacterial and antiprotozoal activity and under field conditions, normal densities of bacterial and other parasitic organisms are encountered (9). Thus a coccidiostat having antibacterial and antiprotozoal properties is desirable (7).

     

RNAi-mediated Knockdown of Xist Does Not Rescue the Impaired Development of Female Cloned Mouse Embryos

In mice, one of the major epigenetic errors associated with somatic cell nuclear transfer (SCNT) is ectopic expression of Xist during the preimplantation period in both sexes. We found that this aberrant Xist expression could be impeded by deletion of Xist from the putative active X chromosome in donor cells. In male clones, it was also found that prior injection of Xist-specific siRNA could significantly improve the postimplantation development of cloned embryos as a result of a significant repression of Xist at the morula stage. In this study, we examined whether the same knockdown strategy could work as well in female SCNT-derived embryos. Embryos were reconstructed with cumulus cell nuclei and injected with Xist-specific siRNA at 6–7 h after oocyte activation. RNA FISH analysis revealed that siRNA treatment successfully repressed Xist RNA at the morula stage, as shown by the significant decrease in the number of cloud-type Xist signals in the blastomere nuclei. However, blastomeres with different sizes (from “pinpoint” to “cloud”) and numbers of Xist RNA signals remained within single embryos. After implantation, the dysregulated Xist expression was normalized autonomously, as in male clones, to a state of monoallelic expression in both embryonic and extraembryonic tissues. However, at term there was no significant improvement in the survival of the siRNA-injected cloned embryos. Thus, siRNA injection was largely effective in repressing the Xist overexpression in female cloned embryos but failed to rescue them, probably because of an inability to mimic consistent monoallelic Xist expression in these embryos. This could only be achieved in female embryos by applying a gene knockout strategy rather than an siRNA approach.     

Safety and functional outcomes associated with short-term rehabilitation therapy in the post-operative management of tibial plateau leveling osteotomy

This retrospective cohort study using electronic questionnaires compared the perioperative complication rates of tibial plateau levelling osteotomy (TPLO) surgery and the 8-week, 6-month, and 1-year functional outcomes, between rehabilitation and traditional post-operative management. Dogs were placed into 1 of 2 cohort groups based on attending veterinarian’s selected management: i) “traditional” involving restriction to cage rest and leash walking, and ii) “rehabilitation” performed by a certified practitioner. There was no statistically significant difference in complication rates in the perioperative period between the 2 treatment cohorts (P > 0.1). The rehabilitation group was 1.9 times more likely to reach full function at 8 wk (P = 0.045). Conversely, the traditional group was 2.9 times more likely be categorized as having unacceptable function at 8 wk after surgery (P = 0.05). This study suggests that rehabilitation performed by a certified practitioner is safe and may improve short-term outcomes when used in the initial postoperative management for dogs treated with TPLO.     

Serological evidence of Anaplasma spp., Borrelia burgdorferi and Ehrlichia canis in dogs from the Republic of Korea by rapid diagnostic test kits

BackgroundEmergent and re-emergent canine tick-borne infections are attracting increasing attention worldwide. The rise in pet ownership and the close relationship between dogs and their owners are the most concerning factors because dogs may act as competent reservoirs for human tick-transmitted infectious agents.ObjectivesThis study contributes to the epidemiological surveillance of canine tick-transmitted infections with zoonotic risk in the Republic of Korea (ROK) by investigating the seroprevalence of the pathogens, Anaplasma spp., Borrelia burgdorferi, and Ehrlichia canis.MethodsFour hundred and thirty whole blood samples from domestic dogs were collected in seven metropolitan cities and nine provinces in the ROK and tested using SensPERT Ab test kits (VetAll Laboratories®) to detect seroreactive animals.ResultsThe seroprevalence rates identified were 9.8% (42/430) for Anaplasma spp., 2.8% (12/430) for B. burgdorferi, and 1.4% (6/430) for E. canis. The risk factors evaluated in this study that could be associated with the development of a humoral immune response, such as sex, age, and history of tick exposure, were similar. There was only one exception for dogs seroreactive to Anaplasma spp., where the risk factor “tick exposure” was statistically significant (p = 0.047).ConclusionsThis serological survey exhibited the widespread presence of Anaplasma spp., B. burgdorferi, and E. canis throughout the ROK. Hence, dogs may play a key role as the sentinel animals of multiple zoonotic infectious agents in the country.     

Immune and inflammatory responses in pigs infected with Trichuris suis and Oesophagostomum dentatum

The aim of the present study was to investigate parasite induced immune responses in pigs co-infected with Trichuris suis and Oesophagostomum dentatum as compared to mono-species infected pigs. T. suis is known to elicit a strong immune response leading to rapid expulsion, and a strong antagonistic effect on O. dentatum populations has been observed in co-infected pigs. Forty-eight helminth naïve pigs were allocated into 4 groups in a 2-factorial design. Two groups were trickle inoculated with either 10 T. suis eggs/kg/day (Group T) or 20 O. dentatum L3/kg/day (Group O). Group OT was infected with same levels of both T. suis and O. dentatum (Group OT) and Group C remained uninfected. In each group, six pigs were necropsied after 35 days and the remaining pigs after 71 days. Parasite E/S-antigen specific serum antibodies were quantified by an in-direct ELISA. qPCR was used to measure the expression of immune function related genes in the mucosa of proximal colon and the draining lymph node. Highly significant interactions were identified for O. dentatum specific IgG1 (p < 0.0001) and IgG2 (p < 0.0006) antibodies with a remarkable 2-fold higher antibody response in group OT pigs as compared to group O. These findings indicated that T. suis enhanced the antibody response against O. dentatum in Group OT. The gene expression data confirmed a strong Type 2 response to T. suis (e.g. marked increase in IL-13, ARG1 and CCL11) and clearly weaker in amplitude and/or delayed onset response to O. dentatum in the single infected group. Interactions were found between the two nematodes with regard to several cytokines, e.g. the increase in IL-13 observed in Group T was absent in Group OT (p = 0.06, proximal colon mucosa, 35 and 71 p.i.). Some of these immune response-related interactions may support, or even partially explain, the observed interactions between the two worm populations in co-infected pigs.     

Pathological findings of hemorrhagic bowel syndrome (HBS) in six dairy cattle cases

Six adult dairy cows clinically diagnosed as hemorrhagic bowel syndrome (HBS) were the subjects of this study. The involved intestinal lesions were fixed in formalin and examined macroscopically and histopathologically. Pathological examinations revealed large intramural hematomas with necrotic foci, resulting in luminal obstruction. The mucosal layer in the lesions was detached from the intestinal wall, and there were no hemorrhagic changes in the lumen. The intramural hematomas were sometimes covered with histologically intact mucosal layer. These pathological findings were not consistent with those of “intraluminal blood clots” reported previously. Gram-positive and anti-Clostridium antibody-positive short bacilli were found in hemorrhagic necrotic areas. However, the exact relationship between Clostridium spp. observed in the lesions and HBS remains unclear, because this bacterium is a normal inhabitant in cattle.     

Do stocking rate and a simple run management practice influence the infection of laying hens with gastrointestinal helminths?

The aim of this experiment conducted at four sites in Switzerland was to investigate the transmission and infectivity of the two main helminth parasite species of poultry (Ascaridia galli and Heterakis gallinarum) in outdoor runs with two different stocking rates. Additionally, the influence of a simple management practice (mowing of run) on helminth transmission was studied. Three run types were created on each site: runs C served as control (stocking rate 10 m²/hen, no management), runs B corresponded to runs C but were managed (10 m²/hen, management). In runs A stocking rates were doubled compared to control runs (5 m²/hen, no management). During two subsequent layer flocks, a set of parasitological parameters (faecal egg counts (FECs), prevalence, worm burdens in hens and in tracer animals, helminth eggs in soil) as well as parameters describing the run vegetation were determined. The increased stocking rate (runs A) led to a larger proportion of bare soil and to a reduction of the average vegetation height. In runs with a lower stocking rate (B and C), the proportion of bare soil did not increase during the experimental period. Irrespective of the run type, numbers of helminth eggs in the soil decreased significantly with an increasing distance to the hen houses, while the percentage of ground coverage as well as vegetation height increased. However, across runs the correlation between the percentage of ground cover and the values of eggs per gram soil between runs was very low (r² = 0.0007, P = 0.95) indicating a non-causal relationship. Significant differences in FEC were found in flock 2 (P < 0.001): FEC of hens in managed runs B were 24% lower (P < 0.05) than those of the control animals. Although not significant, the corresponding prevalence was lower (−9.7%) in hens from managed runs as well. Hens from runs with a high stocking rate (A) had significantly higher FEC than hens from control runs (C). In flock 2 management (n.s.) and higher stocking rates (−62%, P < 0.05) decreased the worm burdens. Tracer animals from runs with a high stocking rate (A) had significantly higher FEC than tracers from runs B and C in two tracer series. This was not reflected in the worm burdens. Overall, the stocking rate of hens in the outdoor run seemed not to influence the transmission patterns of A. galli and H. gallinarum and repeated mowing of runs did not reduce helminth infections. Lower stocking rates, however, led to a substantial improvement of the run vegetation.