Marcin Mickiewicz

Seroprevalence of Toxoplasma gondii in wild boars, red deer and roe deer in Poland

Little is known about the prevalence of Toxoplasma gondii in wild life, particularly game animals in Poland. Meat juice collected during the 2009/2010 and 2010/2011 hunting seasons from 552 red deer (Cervus elaphus), 367 wild boars (Sus scrofa) and 92 roe deer (Capreolus capreolus) was tested for T. gondii antibodies using the multi-species ID Screen Toxoplasmosis Indirect kit (IDvet, Montpellier, France). Antibodies to T. gondii were detected in 24.1% of red deer (95% CI: 20.7%, 27.8%), 37.6% of wild boar (95% CI: 32.8%, 42.7%) and 30.4% of roe deer (95% CI: 22.0%, 40.5%). To the authors’ best knowledge, this is the first epidemiological report of T. gondii prevalence in red deer, roe deer and wild boars in Poland. T. gondii is present in wildlife animal tissues and consumption of the game may be a potential source of infection for humans.

Reference intervals of echocardiographic measurements in healthy adult dairy goats

Objectives To determine references intervals for echocardiographic measurements in adult dairy goats. Animals 125 clinically healthy, adult dairy goats aged 2–9 years, belonging to two breeds–Polish Fawn Improved (PFI, n = 64, weight range from 46 to 73, median of 58.5kg) and Polish White Improved (PWI, n = 61, weight range from 48 to 80 kg, median of 67.9kg), closely related to French Alpine and Saanen, respectively. Methods Non-invasive transthoracic echocardiography examination was performed in unsedated goats in a standing position. Two-dimensional, M-mode and pulsed wave Doppler measurements were obtained. A non-parametric method was applied for determination of reference intervals. Measurements for the two breeds were compared using an analysis of covariance to control for their body weight. Repeatability was assessed using a between-day coefficient of variation and a coefficient of repeatability. Results Following reference intervals were determined: aortic diameter in diastole 2.2–3.3, left atrial diameter in systole 2.5–4.3cm cm, the ratio of the left atrial diameter to the aortic diameter 0.96–1.5, right ventricular internal diameter in diastole 0.4–1.7cm, left ventricular internal diameter in systole and diastole 1.8–3.2 and 3.2–5.6 cm, respectively, inter-ventricular septum thickness in systole and diastole 0.7–1.5 and 0.5–1.1cm, respectively, left ventricular posterior-wall in systole and diastole 0.8–1.6 and 0.5–1.2cm, respectively, E-point to septal separation 0.3–0.8cm, left ventricular fractional shortening 28–54%, left ventricular ejection fraction 55–86%, maximum Left and Right Ventricular Outflow Tract velocity 80–140 cm/s and 70–130 cm/s, respectively Left and Right Ventricular Outflow Tract pressure gradient 2.5–8.9mmHg and 1.9–6.5mmHg, respectively. Most of the differences between the two breeds could be attributed to different body weight. Conclusions The study provides echocardiographic reference intervals determined on the highest sample of apparently healthy goats so far enrolled.

Acute-phase proteins in pregnant goats: a longitudinal study

We documented changes in serum amyloid A (SAA) and haptoglobin (Hp) concentration in goats during pregnancy, as measured by competitive ELISAs. Fifteen does (pregnant group) and 20 castrated males (control group) were enrolled in the study. Blood samples were collected on the same day from all 35 goats, 7 times throughout the study period: at mating, then once every month, during the week preceding kidding, and 1 mo after kidding. Baseline SAA and Hp concentrations at mating were identical in the 2 groups. In the pregnant group, SAA concentration rose significantly in the second month and remained elevated until the end of pregnancy, with the peak concentration at kidding. In the control group, SAA concentration remained unchanged compared to the baseline concentration throughout the study. SAA concentration was significantly higher in the pregnant than control group only at the end of the fourth month of pregnancy and at kidding. Hp concentration did not change during pregnancy or between groups. SAA concentration at kidding was affected only by parity of does – it was highest in does in the third and fourth pregnancy and gradually lower in older does.

Change of heart dimensions and function during pregnancy in goats

The study aimed to evaluate the effect of pregnancy on heart diameters and function in goats. Transthoracic echocardiography of 12 female dairy goats of two Polish regional breeds was performed. A Mindray M7 diagnostic ultrasound system with Phased Array transducer was used. Simultaneously, electrocardiography was recorded. All animals were examined four times - at mating season, at the end of the first trimester, at the end of the second trimester and just before kidding. Eleven measurements were taken each time: aortic and left atrial diameter (AoD and LAD), right and left ventricular internal diameter in diastole (RVIDd and LVIDd), left ventricular internal diameter in systole (LVIDs), inter-ventricular septum thickness in diastole and systole (IVSd and IVSd) and left ventricular posterior wall in diastole and systole (LVPWd and LVPWs), maximum left and right ventricular outflow tract velocity (RVOT Vmax and LVOT Vmax). Nine consecutive measurements were derived: the ratio of the left atrial diameter to the aortic diameter (AoD/LAD), left ventricular fractional shortening (FS%), left ventricular ejection fraction (EF%), maximum outflow tract pressure gradients (RVOT PGmax and LVOT PGmax), left ventricular end-diastolic volume (LVEDV) and left ventricular end-systolic volume (LVESV), stroke volume (SV) and cardiac output (CO). HR, LAD, LVPWs, IVSs increased significantly in the first trimester. AoD and RVIDd were significantly higher around parturition. LVIDd, FS%, EF%, SV and CO rose both in the first and third trimester. No measurement decreased during pregnancy. The study confirms that pregnancy causes changes in the heart size and functioning.

Relationship between the dissemination of small ruminant lentivirus infection in goat herds and opinion of farmers on the occurrence of arthritis

Small ruminant lentivirus (SRLV) infection manifests itself mainly with chronic progressive arthritis affecting mainly carpal joints. The data from serological and questionnaire surveys were retrospectively analyzed to determine how the dissemination of SRLV infection in the herd influenced farmer’s subjective opinion on the occurrence of swelling of carpal joints (considered as a proxy of arthritis). Between 1996 and 2017 153 different Polish dairy goat herds counting at least 20 adult goats were serologically screened for CAE and their owners were asked about their opinion on the occurrence of arthritis (never, rarely, often). Of them 73 SRLV-seropositive herds, in which true seroprevalence had been estimated, were included in the analysis. The ordinal logistic regression model was developed to determine the relationship between the true within-herd seroprevalence and the probability that the farmer would observe arthritis in the herd never, rarely or often. True within-herd seroprevalence ranged from 0.2% to 100% with the median of 34.6%. Farmers declared not to have observed arthritis in 40 (54.8%) herds, to have seen it rarely in 9 (12.3%) of herds, and to have observed it often in 24 (32.9%) of herds. The model proved that the probability of observing goats with carpal arthritis in the herd was significantly linked to the true within-herd seroprevalence (OR = 1.058, CI 95% from 1.037 to 1.078; p<0.001), but this relationship was not linear and SRLV infection proved to remain unapparent to farmers even when a considerable part of the herd had already become infected. Concluding, the study shows that when the farmer realizes that goats in the herd suffer from arthritis, SRLV infection is almost certainly already widespread in the herd.

Comparison of oscillometric, Doppler and invasive blood pressure measurement in anesthetized goats

Arterial blood pressure (BP) can be measured directly using an invasive intra-arterial method. This method is considered a gold standard, however it is potentially hazardous and requires expensive equipment and professional skills. Therefore, two non-invasive methods–Doppler ultrasonic sphygmomanometry and oscillometry–have been introduced in veterinary medicine. Their accuracy has so far been reliably evaluated in various animal species, however only one study included a small group of goats. Therefore, we carried out a large-scale study which aimed to evaluate agreement between the two non-invasive methods and invasive intra-arterial BP measurement in anesthetized goats at various age. The study included 122 goats of two Polish local breeds (Polish White Improved and Polish Fawn Improved): 67 adult females, 35 adult males, and 20 two-month-old female kids. Goats were anesthetized with the intravenous mixture of xylazine and ketamine. BP was measured simultaneously with the three methods in each goat with 7 measurements on average taken. The study showed that according to the criteria of the American College of Veterinary Internal Medicine (ACVIM) oscillometric method yielded BP measurements sufficiently consistent with invasive intra-arterial method in anesthetized adult goats– 95% of oscillometric BP measurements were expected to differ from invasive BP measurements by at most ±20–25 mmHg. The agreement was worse in goat kids–oscillometry significantly overestimated invasive BP measurements, which resulted in highly asymmetrical 95% limits of agreement. Doppler systolic BP very poorly conformed to invasive systolic BP both in adult goats and in kids and all the ACVIM criteria were violated. Concluding, oscillometry, but not Doppler ultrasonic sphygmomanometry, may be regarded as an alternative to invasive BP measurement in large-scale scientific studies involving adult goats, however, individual oscillometric BP measurements should be treated with caution as estimated 95% limits of agreement were wide.

Use of two commercial caprine arthritis-encephalitis immunoenzymatic assays for screening of arthritic goats

Roughly one-fourth of goats infected with small ruminant lentivirus (SRLV) develop caprine arthritis-encephalitis (CAE). We compared the profile of antibody response to surface glycoprotein (SU), and combined transmembrane glycoprotein and capsid protein (TM/CA) in SRLV-infected arthritic and asymptomatic goats, and determined the ability of 2 commercial ELISAs to distinguish between arthritic and asymptomatic goats. We used sera from 312 SRLV-seropositive dairy goats in a whole-virus ELISA; 222 were collected from arthritic goats and 90 from apparently healthy goats. Sera were screened with a competitive inhibition ELISA based on SU antigen (SU-ELISA) and an indirect ELISA based on TM and CA antigens (TM/CA-ELISA). Receiver operating characteristic (ROC) curves were prepared for both ELISAs, and areas under the ROC curves (AUC) were compared. The proportion of goats with antibody response stronger to SU antigen than to TM/CA antigen was significantly higher among arthritic than asymptomatic goats (58.1% vs. 28.9%; p < 0.001). Antibody response to SU antigen was a good predictor of the arthritic form of CAE: AUC for SU-ELISA was 89.7% (95% CI: 85.2%, 94.2%), compared to 59.3% (95% CI: 51.9%, 66.8%) for TM/CA-ELISA (p < 0.001). With the cutoff set at percentage of inhibition of 56%, SU-ELISA had sensitivity of 86.9% (95% CI: 81.9%, 90.7%) and specificity of 84.4% (95% CI: 75.6%, 90.5%) in discriminating between arthritic and asymptomatic goats.

MLST and RAPD molecular analysis of Staphylococcus aureus subsp. anaerobius isolated from goats in Poland

Staphylococcus aureus subsp. anaerobius is an etiological agent of Morel’s disease in small ruminants. The infection results in superficial abscesses located near lymph nodes. In the study, molecular analysis based on multilocus sequence typing (MLST) of seven housekeeping genes (arcC, aroE, glp, gmk, pta, tpi, yqiL) and random amplified polymorphic DNA (RAPD) was carried out on 19 S. aureus subsp. anaerobius strains isolated from two different goat herds from Poland. All of the 19 S. aureus subsp. anaerobius strains were found to belong to single MLST and RAPD types which support the high clonality level of this agent. However, the results obtained show clearly that the S. aureus subsp. anaerobius clone found in goats in Poland is different from those previously described. However, it is identical to the ATCC 38844 strain isolated from sheep in Spain, which has not been so far genotyped using MLST.

Influence of true within-herd prevalence of small ruminant lentivirus infection in goats on agreement between serological immunoenzymatic tests

The study was conducted to evaluate influence of the true within-herd prevalence of small ruminant lentivirus (SRLV) infection on agreement beyond chance between three different types of commercial serological ELISAs. Blood samples were collected from 865 goats from 12 dairy goat herds. Serum samples were tested using three commercial ELISA kits: whole-virus indirect ELISA (wELISA), indirect ELISA based on recombined TM and CA antigens (TM/CA-ELISA), and competitive-inhibition ELISA based on SU antigen (SU-ELISA). Herds were classed into three prevalence strata of high (>50%), moderate (10-50%) and low (<10%) true within-herd prevalence of SRLV infection. The latter was estimated on the basis of results of wELISA adjusted by its sensitivity and specificity. Agreement beyond chance between the three ELISAs was assessed at two levels. First, the general agreement was determined using two coefficients corrected for chance-agreement: Cohens kappa and Gwets AC1. Then, agreement between tests was evaluated using Gwets AC1 separately in the three prevalence strata and compared between them by computing 95% confidence intervals for differences with a Bonferroni correction for multiple comparisons. The general agreement between the three tests was very good: wELISA and TM/CA-ELISA - Cohens kappa of 81.8% (CI 95%: 77.9% to 85.7%), Gwets AC1 of 82.7% (CI 95%: 79.0% to 86.4%); wELISA and SU-ELISA - Cohens kappa of 83.2% (CI 95%: 79.4% to 86.9%), Gwets AC1 of 83.9% (CI 95%: 80.4% to 87.5%); TM/CA-ELISA and SU-ELISA - Cohens kappa of 86.0% (CI 95%: 82.6% to 89.5%), Gwets AC1 of 86.9% (CI 95%: 83.6% to 90.1%). However, agreement between ELISAs was significantly related to the within-herd true prevalence - it was significantly lower (although still high) when within-herd true prevalence was moderate (Gwets AC1 between 67.2% and 78.7%), whereas remained very high, when true within-herd prevalence was either >50% (Gwets AC1 between 91.9% and 98.8%) or <10% (Gwets AC1 between 94.7% and 98.4%). Concluding, the three different commercial ELISAs for SRLV infection in goats available on the market yield highly consistent results. However, their agreement is affected by the true within-herd prevalence in a tested population, and the worse (although still high) agreement should be expected, when the percentage of infected goats is moderate.