Use of physical examination, electrocardiography, radiography, and biomarkers to predict echocardiographic stage B2 myxomatous mitral valve disease in preclinical Cavalier King Charles Spaniels

INTRODUCTION

Cavalier King Charles Spaniels (CKCS) are predisposed to developing myxomatous mitral valve disease (MMVD). Dogs with stage B2 MMVD benefit from medication.

OBJECTIVES

To develop (1) breed-specific cut-offs for individual screening tests and (2) predictive models utilizing physical examination (PE), ECG, radiograph, and blood-based biomarker variables in combination for identification of echocardiographic stage B2 MMVD in preclinical CKCS.

ANIMALS

Adult, preclinical CKCS not receiving cardiac medications (N = 226).

MATERIALS AND METHODS

Prospective, cross-sectional study. Enrolled CKCS underwent PE, ECG, radiography, Doppler blood pressure measurement, echocardiography, and biomarker testing. Dogs were grouped by MMVD stage using echocardiography only. The discriminatory ability of individual tests to identify stage B2 was assessed, and prediction models were developed using variables derived from four 'tests' (PE, ECG, radiography, and biomarkers).

RESULTS

N-terminal pro-B-type natriuretic peptide (NT-proBNP) and radiographic vertebral heart size (VHS) had the best discriminatory ability of individual diagnostic tests to differentiate stage A/B1 CKCS from stage B2, with an area under the curve (AUC) of 0.855 and 0.843, respectively. An NT-proBNP ≥1138 pmol/L or a VHS ≥11.5 had high specificity for predicting stage B2 (90.1% and 90.6%, respectively). Prediction models incorporating variables from multiple tests had better discriminatory ability than single tests. The four-test prediction model had an AUC of 0.971. Three and two-test models had AUCs ranging between 0.925-0.959 and 0.895-0.949, respectively.

CONCLUSIONS

Both NT-proBNP and VHS have good utility for predicting echocardiographic stage B2 MMVD in CKCS as individual tests. Prediction models incorporating multiple test variables have superior discriminatory ability.

Pacemaker-lead-associated thrombosis in dogs: a multicenter retrospective study

INTRODUCTION

Pacemaker implantation is the treatment of choice for clinically relevant bradyarrhythmias. Pacemaker-lead-associated thrombosis (PLAT) occurs in 23.0-45.0% of people with permanent transvenous pacemakers. Serious thromboembolic complications are reported in 0.6-3.5%. The incidence of PLAT in dogs is unknown.

ANIMALS, MATERIALS AND METHODS

multicenter retrospective study of seven centers with 606 client-owned dogs undergoing permanent pacemaker implantation between 2012 and 2019. 260 dogs with a transvenous pacemaker with echocardiographic follow-up, 268 dogs with a transvenous pacemaker without echocardiographic follow-up and 78 dogs with an epicardial pacemaker.

RESULTS

10.4% (27/260) of dogs with transvenous pacemakers and echocardiographic follow-up had PLAT identified. The median time to diagnosis was 175 days (6-1853 days). Pacemaker-lead-associated thrombosis was an incidental finding in 15/27 (55.6%) dogs. Of dogs with a urine protein:creatinine ratio measured at pacemaker implantation, dogs with PLAT were more likely to have proteinuria at pacemaker implantation vs. dogs without PLAT (6/6 (100.0%) vs. 21/52 (40.4%), P=0.007). Urine protein:creatinine ratio was measured in 12/27 (44.4%) dogs at PLAT diagnosis, with proteinuria identified in 10/12 (83.3%) dogs. Anti-thrombotic drugs were used following the identification of PLAT in 22/27 (81.5%) dogs. The thrombus resolved in 9/15 (60.0%) dogs in which follow-up echocardiography was performed. Dogs with PLAT had shorter survival times from implantation compared to those without PLAT (677 days [9-1988 days] vs. 1105 days [1-2661 days], P=0.003).

CONCLUSIONS

Pacemaker-lead-associated thrombosis is identified in 10.4% (27/260) of dogs following transvenous pacing, is associated with proteinuria, can cause significant morbidity, and is associated with reduced survival times.

Deletion of porcine BOLL is associated with defective acrosomes and subfertility in Yorkshire boars

A recessive sperm defect of Yorkshire boars was detected more than a decade ago. Affected boars produce ejaculates that contain spermatozoa with defective acrosomes, resulting in low fertility. The acrosome defect was mapped to porcine chromosome 15 but the causal mutation has not been identified. We re-analyzed microarray-derived genotypes of affected boars and confirmed that the acrosome defect maps to a 12.24 Mb segment of porcine chromosome 15. To detect the mutation causing defective acrosomes, we sequenced the genomes of two affected and three unaffected boars to an average coverage of 11-fold. Read depth analysis revealed a 55 kb deletion that is associated with the acrosome defect. The deletion encompasses the BOLL gene encoding the boule homolog, an RNA binding protein which is an evolutionarily conserved member of the DAZ (Deleted in AZoospermia) gene family. Lack of BOLL expression causes spermatogenic arrest and sperm maturation failure in many species. Boars that carry the deletion in the homozygous state produce sperm but their acrosomes are defective, suggesting that lack of porcine BOLL compromises acrosome formation. Our findings warrant further research to investigate the role of BOLL during spermatogenesis and sperm maturation in pigs.

Zinc Deficiency-Like Syndrome in Fleckvieh Calves: Clinical and Pathological Findings and Differentiation from Bovine Hereditary Zinc Deficiency

Background

Zinc deficiency‐like (ZDL) syndrome is an inherited defect of Fleckvieh calves, with striking similarity to bovine hereditary zinc deficiency (BHZD). However, the causative mutation in a phospholipase D4 encoding gene (PLD4) shows no connection to zinc metabolism.

Objectives

To describe clinical signs, laboratory variables, and pathological findings of ZDL syndrome and their utility to differentiate ZDL from BHZD and infectious diseases with similar phenotype.

Animals

Nine hospitalized calves with crusting dermatitis and confirmed mutation in PLD4 and medical records from 25 calves with crusting dermatitis or suspected zinc deficiency.

Methods

Prospective and retrospective case series.

Results

The 9 calves (age: 5–53 weeks) displayed a moderate to severe crusting dermatitis mainly on the head, ventrum, and joints. Respiratory and digestive tract inflammations were frequently observed. Zinc supplementation did not lead to remission of clinical signs in 4 calves. Laboratory variables revealed slight anemia in 8 calves, hypoalbuminemia in 6 calves, but reduced serum zinc concentrations in only 3 calves. Mucosal erosions/ulcerations were present in 7 calves and thymus atrophy or reduced thymic weights in 8 calves. Histologically, skin lesions were indistinguishable from BHZD. Retrospective analysis of medical records revealed the presence of this phenotype since 1988 and pedigree analysis revealed a common ancestor of several affected calves.

Conclusions and Clinical Importance

ZDL syndrome should be suspected in Fleckvieh calves with crusting dermatitis together with diarrhea or respiratory tract inflammations without response to oral zinc supplementation. Definite diagnosis requires molecular genetic confirmation of the PLD4 mutation.

Asian horses deepen the MSY phylogeny

Humans have shaped the population history of the horse ever since domestication about 5500 years ago. Comparative analyses of the Y chromosome can illuminate the paternal origin of modern horse breeds. This may also reveal different breeding strategies that led to the formation of extant breeds. Recently, a horse Y-chromosomal phylogeny of modern horses based on 1.46 Mb of the male-specific Y (MSY) was generated. We extended this dataset with 52 samples from five European, two American and seven Asian breeds. As in the previous study, almost all modern European horses fall into a crown group, connected via a few autochthonous Northern European lineages to the outgroup, the Przewalski's Horse. In total, we now distinguish 42 MSY haplotypes determined by 158 variants within domestic horses. Asian horses show much higher diversity than previously found in European breeds. The Asian breeds also introduce a deep split to the phylogeny, preliminarily dated to 5527 ± 872 years. We conclude that the deep splitting Asian Y haplotypes are remnants of a far more diverse ancient horse population, whose haplotypes were lost in other lineages.

Identification of a haplotype associated with cholesterol deficiency and increased juvenile mortality in Holstein cattle

Over the last decades, several genetic disorders have been discovered in cattle. However, the genetic background of disorders in calves is less reported. Recently, German cattle farmers reported on calves from specific matings with chronic diarrhea and retarded growth of unknown etiology. Affected calves did not respond to any medical treatment and died within the first months of life. These calves were underdeveloped in weight and showed progressive and severe emaciation despite of normal feed intake. Hallmark findings of the blood biochemical analysis were pronounced hypocholesterolemia and deficiency of fat-soluble vitamins. Results of the clinical and blood biochemical examination had striking similarities with findings reported in human hypobetalipoproteinemia. Postmortem examination revealed near-complete atrophy of the body fat reserves including the spinal canal and bone marrow. To identify the causal region, we performed a genome-wide association study with 9 affected and 21,077 control animals genotyped with the Illumina BovineSNP50 BeadChip (Illumina Inc., San Diego, CA), revealing a strong association signal on BTA 11. Subsequent autozygosity mapping identified a disease-associated haplotype encompassing 1.01 Mb. The segment of extended homozygosity contains 6 transcripts, among them the gene APOB, which is causal for cholesterol disorders in humans. However, results from multi-sample variant calling of 1 affected and 47 unaffected animals did not detect any putative causal mutation. The disease-associated haplotype has an important adverse effect on calf mortality in the homozygous state when comparing survival rates of risk matings vs. non-risk matings. Blood cholesterol values of animals are significantly associated with the carrier status indicating a codominant inheritance. The frequency of the haplotype in the current Holstein population was estimated to be 4.2%. This study describes the identification and phenotypic manifestation of a new Holstein haplotype characterized by pronounced hypocholesterolemia, chronic emaciation, growth retardation, and increased mortality in young cattle, denominated as cholesterol deficiency haplotype. Our genomic investigations and phenotypic examinations provide additional evidence for a mutation within the APOB gene causing cholesterol deficiency in Holstein cattle.

138 DEVELOPMENTAL COMPETENCE OF BIOPSIED AND SPLIT BOVINE EMBRYOS

The aim of the present study was to develop a reliable method to simultaneously split and biopsy valuable bovine embryos for a complete genomic evaluation (gender, polledness, and hereditary abnormalities) and to estimate the breeding value of progeny for traits of economic importance immediately after embryo recovery. A total of 208 good quality embryos collected from superovulated German Simmental animals were biopsied immediately after recovery using an inverse microscope (Zeiss, Germany) at 50× magnification with a single-use steel blade mounted on a holder (Bausch & Lomb, Germany) attached to a micromanipulator (Eppendorf, Germany). Biopsy was performed either by splitting the embryo and cutting of one-third of a half [G1: morulae (M), n = 50; early blastocysts (EB), n = 24; blastocysts (B), n = 16], by just splitting in equal halves (G2: M, n = 16; B, n = 2), or by cutting of just a small biopsy of the embryo (G3: M, n = 53) or of the trophoblast (G3: EB, n = 19; B, n = 28). Biopsied cells were immediately used for DNA amplification. Biopsied embryos (E) and demi-embryos (DE) were in vitro cultured in SOF, under mineral oil, at 39°C and 5% CO2, 5% O2, 90% N2 for 24 h, after which survival was recorded. Survival rate of G1 (survival of at least 1 DE: M, 98.0%; EB, 100.0%; B, 93.8%), G2 (survival of DE: M, 75.0%; B, 100.0%), and G3 (embryo survival: M, 96.3%; EB, 100.0%; B, 96.4%) were similar, but in relation to the number of original embryo the highest ratio of DE was obtained in G1 (1.67) v. G2 (0.88) and G3 (0.97; G1:G2/G3; P < 0.01). Within G1, the highest ration to the original number of embryos was by using M (1.78), followed by EB (1.75) and B (1.19; M/EB:B; P < 0.05). To verify the viability of biopsied embryos some DE from G1 (1, the nonbiopsied DE, n = 7, or 2, the biopsied and the nonbiopsied DE per recipient, n = 21), G2 (1 DE per recipient, n = 13), and G3 (1 E per recipient, n = 8) were transferred after 24 h of culture. Overall pregnancy rate (Day 42) of G1, G2, and G3 was 64.3, 23.1, and 50.0%, respectively (G1 : G2; P < 0.05). In G1, pregnancy rates (Day 42) of biopsied embryos differed significantly if either 1 or 2 DE were transferred per recipient (28.6 v. 76.2%, respectively; P < 0.05). A twin pregnancy rate of 38.9% was observed by ultrasonography in recipients when 2 DE were transferred. The results suggest that high survival rates can be obtained with the G1 technique, and splitting during biopsy can increase productivity in programs aimed to evaluate the genomic constitution of early stage embryos. Funded by the Bayerische Forschungsstiftung (AZ-1031-12).

84 PAIRS OF BLASTOMERES FROM BOVINE DAY 5 MORULAE ARE ABLE TO CONTRIBUTE TO INNER CELL MASS AND TROPHECTODERM IN CHIMERIC EMBRYOS GENERATED BY AGGREGATION WITH TWO DAY 4 MORULAE

The multiplication of high-value embryos by chimera formation using asynchronic aggregation is a promising alternative to embryonic cell nuclear transfer. Single blastomeres from a donor embryo are aggregated with 2 host embryos, thus several chimeras can be constructed per donor embryo. Due to the advanced developmental stage, the donor blastomeres are likely to contribute to the inner cell mass (ICM) and later give rise to the embryo proper, whereas the host embryos form extra-embryonic tissues. To test if pairs of blastomeres from Day 5 morulae are able to form the ICM when aggregated with 2 Day 4 host embryos, we produced transgenic donor embryos carrying a fluorescent reporter gene (enhanced green fluorescent protein, eGFP) by using semen from an eGFP transgenic bull (Reichenbach et al. 2010 Transgenic Res. 19, 549–556) for in vitro fertilization and in vitro host embryos produced by a standard procedure. The zona pellucida of all embryos was removed by treatment with 1 mg mL–1 pronase. Donor embryos were assessed for eGFP expression by fluorescence microscopy and disaggregated by gentle pipetting after incubation in Mg2+- and Ca2+-free medium. Pairs of blastomeres were then placed between 2 host embryos and cultured individually in a well-of-the-well culture dish. On Day 6 after aggregation, fully developed blastocysts were assessed for eGFP fluorescence. In 3 replicates, n = 30 chimeras were produced by aggregation; 13 (43%) developed to blastocysts, of which 2 (15%) showed local eGFP expression in the ICM and 7 (54%) showed a generalized expression. From the results of this study we conclude that Day 5 morulae may be multiplied in an efficient manner by using the chimera formation technique, which makes this approach applicable to ex vivo-derived embryos. In future investigations we will study the effect of using donor blastomeres from either the inside or outside of the donor morula and test the use of tetraploid host embryos to increase the rate of blastocysts with the desired genotype in the ICM. Finally, we aim to introduce this multiplication approach to the production of genotyped embryos with a genomic estimated breeding value (gEBV) and intend to produce calves with identical gEBV.Funded by the Bavarian Research Foundation (AZ-1031–1).

316 GENOMIC EVALUATION OF BOVINE EMBRYOS WITHIN 24 HOURS

The aim of this study was to develop a reliable procedure for genomic evaluation of bovine embryos to determine gender, polled status, and hereditary defects within 24 h after collection. German Simmental animals (n = 15) were superovulated (n = 25) using a standard protocol. Embryos were recovered on Day 7 (Day 0 = oestrus). A total of 217 embryos (morula, n = 130; early blastocyst, n = 43; blastocyst, n = 44) were biopsied with a steel blade attached to a micromanipulator. Biopsied cells were immediately transferred into 1 µL TE buffer to a 500 µL reaction tube and embryos were in vitro cultured until genomic results were available. For commonly used molecular genetic methods (e.g. 5′-exonuclease genotyping, PCR or high density genotyping) DNA amounts of 2–200 ng are required. However, the DNA quantity of a single diploid cell amounts to 6 pg only. The embryo biopsies used, usually consists of 10–30 cells, necessitating an artificial amplification of the embryonic genome. Taking all vital measures to avoid external DNA contamination, isothermal whole genome amplification was performed with the REPLI-g Mini Kit (Qiagen, Valencia, CA, USA) using random hexamers and Phi29-Polymerase. Depending on the number of cells, a total DNA amount of 4–7 µg was achieved. Polled status and gender was determined using PCR with subsequent gel-electrophoresis. 5′-exonuclease assays were used to obtain genotypes for the detection of genetic defects. At present, eight, mostly Simmental-specific genetic disorders can be examined: three traits associated with severe growth retardation, dwarfism (DW), Braunvieh-haplotype 2 (BH2) and stunted growth (FH2), the lethal skin disorder zinc deficiency-like syndrome (ZDL), a fertility trait bovine male subfertility (BMS), embryonic death Fleckvieh-haplotype 4 (FH4), a bleeding disorder thrombopathia (TP) and arachnomelia (A), within 24 h. On average, 8.7 embryos were biopsied per embryo recovery, i.e. 93.9% of the total number of transferable embryos. Fourteen embryo samples (6.5%) totally failed during analysis, possibly due to the loss of samples. In successful analyses, gender was undetermined in two embryos; remaining embryos were 52.2% female and 47.8% male. Polled status could be analysed in 92.6% of the embryos. The analyses of embryos for possible inherited genetic disorders (healthy, heterozygote, or homozygote; n = 578) were successful in 90.1%. The transfer of biopsied embryos (n = 30) led to 63.3% pregnancies (Day 42). A validation of the present results has to be done as soon as the produced calves are born, demonstrating the reliability of the procedure.Research was funded by the Bayerische Forschungsstiftung (AZ-1031-12).

Quantification of water as a potential risk factor for cross-contamination with Salmonella, Campylobacter and Listeria in a poultry abattoir

Water used in a modern poultry processing line was tested from October 2005 to June 2006 to determine the level of bacteria in an abattoir in Germany. A total of 420 water samples were taken from 14 processing sites (PSs), at 10 times, and from three different hours of the working shift at three sampling hours (SHs) at 5:00 a.m. (SH 1), 9:00 a.m. (SH 2) and 12:00 a.m. (SH 3). Each sample was assessed for the aerobic plate count (APC) and the prevalence of Salmonella, Campylobacter, Listeria and Yersinia over 30 sampling weeks. The APC numbers of each PS from three SHs were compared, and the prevalence of Salmonella, Campylobacter, Listeria and Yersinia from each PS of three SHs was determined as well as change from the initial PS to the end of the processing line. A total of 46 water samples were positive for Salmonella, 120 positive for Campylobacter and 4 positive for Listeria. None of the water samples was found to be positive for Yersinia. During the course of the day, the APC increased. Salmonella was mostly found during SH 1 (5 a.m.) in water from all PSs. A high number of Campylobacter were observed at SH 2 (9 a.m.) and SH 3 (12 a.m.) from all PSs. The results show that water, which is still used in substantial amounts in present poultry processing technology, can serve as a carrier for Salmonella and Campylobacter. The findings indicate that birds might progressively contaminate the equipment and become contaminated via the same equipment, that water at every processing position of the line constitutes a risk and that more attention should be paid to effective water management in the processing plan.

Assessing the relationship between farming practices, laboratory analyses and post-mortem findings: a case study in pig fattening

European Union legislation on animal production associated with food safety requires the collection and management of information and data about the farm, the herd and the individual animal. This paper describes the technical steps of the generation, collection and interpretation of data from 296 pig-fattening farms, belonging to two farming associations and using indoor production systems (56 management parameters). The paper also describes post-mortem findings and the results of enzyme-linked immunosorbent assays (ELISA) for antibodies to salmonellae, Trichinella spp. and Yersinia spp. A total of nearly 30 million data points were collected and analysed for this study. The results of the ELISA were negative for Trichinella spp.; for salmonellae and Yersinia spp., both negative and positive results were obtained. Analysis of the farm management parameters showed no significant differences; therefore, the cut-off levels for salmonellae and Yersinia spp. were increased, in order to identify farms with a greater hygiene burden. Post-mortem findings, possibly related to 'farm hygiene', were used in the analysis. As a result, three farms with particular management decisions were identified as potentially having contributed to the high burden of pathogens detected using ELISA. A relationship between laboratory results and farm management parameters assessed from yes/no answers could not be established in this study without further work on the available data set.

Higher precision level at individual laying performance tests in noncage housing systems

With the Weihenstephan funnel nest box, 12 laying hen flocks were tested for their individual laying performance, egg quality, and nesting behavior in a noncage environment. During the whole observation period of 8 yr, a transponder-based data recording system was continuously improved and resulted in a recording accuracy of 97%. At peak production, heritabilities for the number of eggs laid are in some flocks higher than expected. With improved data accuracy, heritability estimates on individual egg weights are more stable. Heritabilities for nesting behavior traits range between a low to moderate level, providing very useful information for laying hen selection to help improve traits that cannot be recorded in cages. Over the years, the benefits of the Weihenstephan funnel nest box for laying hen breeders have grown. This is due to higher data recording accuracies and extended testing capacities, which result in more reliable genetic parameters.

On the limited increase in validation reliability using high-density genotypes in genomic best linear unbiased prediction: observations from Fleckvieh cattle

This study investigated reliability of genomic predictions using medium-density (40,089; 50K) or high-density (HD; 388,951) marker sets. We developed an approximate method to test differences in validation reliability for significance. Model-based reliability and the effect of HD genotypes on inflation of predictions were analyzed additionally. Genomic breeding values were predicted for at least 1,321 validation bulls based on phenotypes and genotypes of at least 5,324 calibration bulls by means of a linear model in milk, fat, and protein yield; somatic cell score; milkability; muscling; udder, feet, and legs score as well as stature. In total, 1,485 bulls were actually HD genotyped and HD genotypes of the other animals were imputed from 50K genotypes using FImpute software. Validation reliability was measured as the coefficient of determination of the weighted regression of daughter yield deviations on predicted breeding values divided by the reliability of daughter yield deviations and inflation was evaluated by the slope of this regression. Model-based reliability was calculated from the model. Distributions for validation reliability of 50K markers were derived by repeated sampling of 50,000-marker samples from HD to test differences in validation reliability statistically. Additionally, the benefit of HD genotypes in validation reliability was tested by repeated sampling of validation groups and calculation of the difference in validation reliability between HD and 50K genotypes for the sampled groups of bulls. The mean benefit in validation reliability of HD genotypes was 0.015 compared with real 50K genotypes and 0.028 compared with 50K samples from HD affected by imputation error and was significant for all traits. The model-based reliability was, on average, 0.036 lower and the regression coefficient was 0.036 closer to the expected value with HD genotypes. The observed gain in validation reliability with HD genotypes was similar to expectations based on the number of markers and the effective number of segregating chromosome segments. Sampling error in the marker-based relationship coefficients causing overestimation of the model-based reliability was smaller with HD genotypes. Inflation of the genomic predictions was reduced with HD genotypes, accordingly. Similar effects on model-based reliability and inflation, but not on the validation reliability, were obtained by shrinkage estimation of the realized relationship matrix from 50K genotypes.

Efficacy of knife disinfection techniques in meat processing

EU Regulation 853/2004 requires that knives used in meat processing be disinfected by submerging them in hot water (+82°C). Alternative procedures are permitted if the efficacy is proved to be equivalent. In the present study, various time-temperature combinations together with pure water, water with lactic acid (2 %), and the use of ultrasound with and without lactic acid (2%) were investigated. Steel plates were covered with fat and protein and then inoculated with a standardized bacterial contamination assembled according to the composition of bacterial contamination found in a previous field trial conducted with regard to the slaughter of pigs. Several combinations with diverse temperatures and time intervals were tested until no microbial load was detectable by using a wet-dry-swab technique that had previously been tested to ensure maximum bacterial recovery. The following were effective in bringing the tested bacterial flora below the detection limit: • 70 °C water bath for 10 s • 60 °C water bath + ultrasound for 5 s • 40 °C water bath + lactic acid (2%) for 10 s • 40 °C water bath + ultrasound + lactic acid (2%) for 5 s In particular, the use of lactic acid permitted a relevant reduction of the temperature, while providing effective sterilization. The use of such non-hazardous food-safe additives is particularly suitable for successful disinfection at lower temperatures.

Short communication: evaluation of bovine milk residues from routine milk testing programs as DNA source for genotyping

Genome-wide association studies and genomic evaluation using a dense set of genetic markers both require a large number of genotyped individuals. Collection of the respective samples contributes substantially to the cost of the approach. In dairy cattle research, the use of residues from routine milk recording would be a cost-saving alternative to obtain samples for an appropriate number of individuals with specific phenotypes in a very short time. To assess the suitability of milk recording residues, we concurrently investigated milk residues obtained after standardized milk recording procedures and blood samples from 115 cows originating from 3 farms with different milking systems by genotyping 15 microsatellite markers. We found that 4% of the milk samples were possibly assigned to the wrong animal (i.e., conflicts) and that at least 27% of the milk residues were contaminated, as indicated by an extra allele not present in the blood sample. These additional alleles primarily originated from a sample with a higher somatic cell score that went through the milk sample analyzer in the milk laboratory before the target sample. Furthermore, additional allele carryover was observed across more than one sample, when the difference in somatic cell count between samples exceeded 100,000 cells/mL. Finally, in several samples, the extra allele could not be traced back to previous samples passing through the milk sample analyzer. One source of those contaminations might be sample collection on-farm due to milk traces from the previously milked cow in the hose. No correlation was found between the farm management and conflicts or contaminations. We conclude that residues from routine milk recording are not suitable for genomic evaluation or genome-wide association studies because of the high prevalence of contamination generated at several steps during the collection and processing of milk residual samples.

Blood parameters and corneal-reflex of finishing pigs with and without lung affections observed post mortem in two abattoirs stunning with CO₂

In two pig abattoirs of different slaughter capacities, the stunning efficacy of CO2 on finishing pigs with and without pneumonic lesions (observed post mortem) was reflected against the corneal-reflex and blood parameters (blood pH, pCO2 and pO2) from individual finishers. Stunning duration was 120 s (abattoir A) and 90 s (abattoir B), respectively. Pneumonia in finisher pigs is frequently observed during post mortem inspection, which may raise concerns about a delay of unconsciousness because of hampered gas exchange in the lungs. The aim of this study was to examine possible pneumonia consequences for stunning efficacy under commercial conditions. For that, corneal reflex, O2 and CO2 partial pressure in the blood as well as blood pH were measured in 2650 finishers from abattoir A and 2100 from abattoir B. The partial pressure of O2 after stunning accounted to about 3 kPa, the partial pressure of CO2 was found at levels of about 24 kPa in abattoir A (after 120 s CO2 exposure) and 17.5 kPa in abattoir B (after 90 s CO2 exposure). In abattoir A, the blood pH was at 6.9, and at 7.0 in abattoir B. The corneal reflex was observed in 6.2% of pigs in abattoir A and 17.1% of pigs in abattoir B. A correlation between pneumonic lesions and blood status was not observed. However, for some individual farms, a significant correlation between pneumonia and corneal reflex was observed.

Antibiotic resistance in Salmonella isolates from imported chicken carcasses in Bhutan and from pig carcasses in Vietnam

The antibiotic resistance in Salmonella isolates from 400 imported chicken carcasses in Bhutan and from 178 pig carcasses in Vietnam were analyzed on a random basis against 14 antimicrobial agents. Among the poultry samples tested, 13% were positive for Salmonella. Salmonella Enteritidis dominated with a prevalence of 80.7%, and 40 of the 42 isolates harbored two or more resistance determinants. For the 178 pigs investigated, 49.4% of the swabs and 34.8% of the lymph nodes were Salmonella positive. The most prevalent serotypes in lymph nodes were Salmonella Derby (50.0%) and Salmonella Typhimurium (27.4%). From the Salmonella isolates from pigs, only 6% were sensitive to the antimicrobial agents tested. The high resistance level of Salmonella isolates from pigs and chicken carcasses to different classes of antimicrobials should be emphasized and encourage a prudent use of these agents in animal farming, especially in pig production.

Tentative chromosomal localization of the bovine major histocompatibility complex by in situ hybridization

A genetic region, most likely the major histocompatibility complex, was assigned to bands q13-23 of cattle chromosome 23 by in situ hybridization using a cloned DNA sequence of a class I gene of the pig major histocompatibility complex.

The bovine gene map

The present status of the bovine gene map as well as some of the methods and strategies important for future efforts in completing the gene map of cattle are reviewed.

Assignment of the HOX2 and HOX3 gene clusters to the bovine chromosome regions 19q17-qter and 5q14-23

The homeobox 2 (HOX2) and homeobox 3 (HOX3) clusters have been chromosomally assigned in cattle by in situ hybridization. The probes employed were a murine probe for the mapping of HOX2 to 19q17-qter and human probes for the mapping of HOX3 to 5q14-q23. These assignments confirm the chromosomal assignment of two syntenic groups, consisting of loci located on human chromosome 12 (bovine chromosome 5) and the long arm of human chromosome 17 (bovine chromosome 19).

Porcine malignant hyperthermia carrier detection and chromosomal assignment using a linked probe

In pigs, the gene for glucosephosphate isomerase (GPI) is linked to the halothane (HAL) gene which is responsible for malignant hyperthermia (MH). A single copy DNA probe, designated GPI8R, has been isolated from a pig genomic library using a porcine GPI cDNA probe. This probe detects, as was the case for the cDNA probe, a five allele polymorphism in SacI and PvuII digested pig DNA. Family studies show that this polymorphism is linked to the HAL locus and hence can be used in carrier detection. In situ hybridization with GPI8R assigned the GPI locus to bands p12-q22 of chromosome 6. We conclude that the HAL linkage group resides on chromosome 6.

Assignment of the porcine tumour necrosis factor alpha and beta genes to the chromosome region 7p11-q11 by in situ hybridization

The loci of the porcine tumour necrosis factor genes, alpha (TNFA) and beta (TNFB), have been chromosomally assigned by radioactive in situ hybridization. The genomic probes for TNFA and TNFB yielded signals above 7p11-q11, a region that has been shown earlier to carry the porcine major histocompatibility locus (SLA). These mapping data along with preliminary molecular studies suggest a genomic organization of the SLA that is similar to that of human and murine major histocompatibility complexes.

Mapping of the gene for G blood group antigens to chromosome 15 in swine

Linkage analysis between size variants of the centromeric region of chromosome 15 and G blood group alleles produced a lod score of 5.03. The maximum likelihood estimate of the recombination fraction is theta = 0.24 with a 95% confidence interval of 0.08 less than theta less than 0.40. Since this is the second time that linkage between a chromosome 15 marker and the G blood group locus has been shown, the assignment of the G blood group locus to chromosome 15 is confirmed.

Factors influencing heart rate variability in patients with severe aortic valve disease

BACKGROUND AND HYPOTHESIS

Heart rate variability (HRV) is an accepted tool for the assessment of cardiovascular autonomic tone. There are no sufficient data concerning its application to patients with severe aortic valve disease (AVD) requiring cardiac surgery.

METHODS

It was the aim of this study to examine HRV and its physiologic correlates in patients with severe aortic valve disease requiring cardiac surgery. The correlates of time domain indices of HRV obtained from 24-h Holter electrocardiographic recordings were analyzed in 36 consecutive patients (23 men and 13 women, mean age 62 +/- 11 years) with AVD prior to cardiac surgery (aortic stenosis: 17 patients, aortic valve regurgitation: 3 patients, combined aortic valve disease: 16 patients).

RESULTS

Low values of HRV were found in the entire study group: SDNN 96.8 +/- 30.9 ms, SDNNI 39.3 +/- 14.4 ms, SDANN 86 +/- 28.9 ms, and RMSSD 30 +/- 18.1 ms. In a univariate analysis, there was no significant correlation between the time domain measures of HRV and age, gender, medication, left ventricular ejection fraction, peak aortic pressure gradient, fraction of aortic valve regurgitation, and left ventricular mass assessed by echocardiography. Patients in advanced functional classes of heart failure [New York Heart Association (NYHA) III or IV] had significantly lower values for SDNN (83.8 +/- 33.6 vs. 107.3 +/- 24.7 ms; p < 0.05) and SDANN (72.7 +/- 29.4 vs. 96.6 +/- 24.3 ms; p < 0.05) than patients in NYHA class I or II. Reassessment of HRV 1 week after aortic valve replacement was performed in 17 patients and showed a significant further decrease of SDNN (102.4 +/- 29.7 vs. 61.5 +/- 23.5 ms; p < 0.001), SDNNI (40.7 +/- 13.6 vs. 23.4 +/- 12.4 ms; p < 0.001) and SDANN (91.8 +/- 29.2 vs. 54.2 +/- 22.8 ms; p < 0.001).

CONCLUSION

Patients with AVD requiring cardiac surgery reveal reduced time domain indices of HRV. This observation is pronounced in patients with a progressed clinical class of heart failure, whereas hemodynamic and echocardiographic parameters seem to have no significant influence on HRV parameters in this population. In addition, there is evidence of a further reduction of HRV time domain indices 1 week after uncomplicated aortic valve replacement.

Incision of the heart during meat inspection of fattening pigs - A risk-profile approach

Meat inspection in the EU is based on Regulation (EC) 854/2004. Accordingly a risk based meat inspection should be implemented. In this paper, the incision of the heart in pig meat inspection is discussed with respect to efficacy. The incision especially can reveal the presence of endocarditis. Here, Erysipelothrixrhusiopathiae (E. rhusiopathiae) and/or Streptococcussuis (S. suis) are of particular concern. Both agents are regarded to be zoonotic agents. There is some evidence for infection of humans via an alimentary pathway. Hence, the occurrence of E. rhusiopathiae and S. suis is a concern of public health (PH) as well as veterinary public health (VPH). However, other measures, including on-farm disease prevention and diagnosis, seem to be more important for food safety. It is concluded that the incision and inspection of the heart is not justifiable with respect to PH aspects.

Variation in neighbouring genes of the dopaminergic and serotonergic systems affects feather pecking behaviour of laying hens

Feather pecking is a behavioural disorder of laying hens and has serious animal welfare and economic implications. One of the several aetiological hypotheses proposes that the disorder results from redirected exploratory behaviour. Variation in the gene encoding the dopamine D4 receptor (DRD4) has been shown to be associated with exploratory behaviour in several species, including in a passerine bird species. We therefore considered DRD4 as a candidate gene for feather pecking. We have annotated DRD4 in the chicken genome and have re-sequenced it in 140 animals belonging to: experimental layer lines divergently selected for high and low propensity to feather pecking; the unselected founder population; and two commercial lines with low and high propensity to feather pecking. We have identified two sub-haplotypes of DRD4 that are highly significantly associated with feather pecking behaviour in the experimental (P = 7.30 x 10(-7)) as well as in the commercial lines (P = 2.78 x 10(-6)). Linkage disequilibrium (LD) extends into a neighbouring gene encoding deformed epidermal autoregulatory factor 1 (DEAF1). The product of DEAF1 regulates the transcription of the gene encoding the serotonin (5-hydroxytryptamine) 1A receptor. Thus, DEAF1 represents another candidate gene for feather pecking. Re-sequencing of five animals homozygous for the 'low-pecking' sub-haplotype and of six animals homozygous for the 'high-pecking' sub-haplotype delineated an LD block of 14 833 bases spanning the two genes. None of the variants in the LD block is obviously functional. However, the haplotype information will be useful to select against the propensity to feather pecking in chicken and to elucidate the functional implications of the variants.

Characterization of a 320-kb region containing the HEXA gene on bovine chromosome 10 and analysis of its association with BSE susceptibility

Bovine spongiform encephalopathy (BSE) belongs to a group of neurodegenerative diseases known as transmissible prion diseases. Recently, variants in the promoter region of the prion protein (PRNP) gene have been shown to have a considerable effect on the susceptibility to BSE. However, a previous genome scan revealed other putative BSE-susceptibility loci. Here, we analysed such a region on BTA10, which contains the functional candidate gene HEXA. Three hundred and twenty kilobases that, besides HEXA, also contain ARIH1, BRUNOL6 and PARP6 were characterized and screened for polymorphisms. Genotyping of 38 SNPs in Holstein-Friesian animals from the UK (350 diseased and 270 controls) revealed two intronic SNPs that were associated with BSE incidence, with experiment-wise P-values of 3.5 x 10(-3) and 7.7 x 10(-3) respectively. Both SNPs were in strong linkage disequilibrium and the rare alleles had a protective effect. These alleles were contained in a haplotype dubbed 'UK-protective' that was significantly overrepresented in the controls with a permuted P-value of 2 x 10(-3). An association study in German Holstein animals (73 diseased and 627 controls) revealed an opposite effect of the 'UK-protective' haplotype in this population, i.e. it was overrepresented in the diseased animals, although not significant after correction for multiple testing. These findings indicate a causal variant for BSE susceptibility on BTA10 in linkage disequilibrium with the markers studied. Candidate gene analyses of the surrounding region and additional association studies will help to clarify the origin of the protective effects and to identify causal variants for BSE susceptibility on BTA10.

Fate of sympathetic trunk ganglia after cutting in German meat plants

To minimize risks from pathogenic prion proteins, particular tissues from bovines and other ruminants have been declared specified risk materials (SRMs), which are required to be removed from the food chain. However, in particular for the sympathetic trunk (ST) as a part of the autonomous nervous system (ANS), which represents a potential transfer route for abnormal prion proteins (PrP(Sc)), this is not the case. Consequently, its destination during cutting procedures deserves attention. In this survey, the handling of the ST in beef cutting plants was recorded during ongoing work. To ease these observations, the ST was separated into five parts, and eight destinations for cuts were identified. By means of an observation sheet, the destination of the respective tissue was recorded. About one-third of the ST went into human consumption, another one-third was disposed of as SRMs, and the last one-third was used for nonfood purposes or disposed of. The rear thoracic and sacral ganglia primarily remained naturally connected to the bones going as SRMs. The stellate, front thoracic, and lumbar ganglia went in a different percent into the food chain. Frequently, workers in the same plant decided differently, even from case to case, on the destination of the tissue, which indicates a lack of standardization.

Microflora of two different types of poultry litter

1. The microbiological composition of litter (straw and wood shavings) was sampled, prior to placing 1-d-old chicks, during housing of the birds and after depopulation. Two independent trials were conducted. 2. The total aerobic plate count (APC) was determined and the predominant microflora of the samples was identified using flow charts. 3. Before chick placement, the APC of wood shavings (about 4.0 log/g) was lower than the APC of straw (about log 7.5/g). With stocking, in both types of litter the APC increased to about log 9.76/g straw-litter and log 9.89/g wood shavings, respectively. After depopulation, the APC remained high (> log 9 in both types of litter) within the period of observation. 4. From both experiments, 1981 isolates were collected and identified, most of them were Gram-positive. During stocking the birds, the number of Gram-positive isolates (in particular Gram-positive irregular rods and Micrococcaceae) increased; after depopulation it stayed at that high value, whereas the number of Gram-negative isolates remained low. In both types of litter the isolates were obtained in a comparable proportion.

Association of the melanocortin 4 receptor with feed intake and daily gain in F2 Mangalitsa x Pietrain pigs

The melanocortin 4 receptor (MC4R) is a key factor in the regulation of energy balance and body weight. Hence it is a candidate for feed intake and energy homeostasis-related traits. Studies in humans and swine have revealed several sequence variants in the gene that are associated with some of these traits. In pigs the coding non-synonymous missense variant Asp298Asn in MC4R has been associated with feed intake, fatness and growth. Here we confirm the association of this Piétrain-derived polymorphism with feed intake and daily gain in the F2 generation of a Mangalitsa x Piétrain cross. In one Piétrain founder animal, we detected an additional non-synonymous missense variant Arg236His. Thus, the MC4R gene could be a useful marker for increased growth in the relatively slow-growing Piétrain breed.

Valve Repair in Aortic Regurgitation without Root Dilatation - Aortic Valve Repair

BACKGROUND

Aortic valve repair was established in the context of aortic root remodeling. Variable results have been reported for isolated valve repair. We analyzed our experience with isolated valve repair and compared the results with those of aortic root remodeling.

METHODS

Between October 1995 and August 2003, isolated repair of the aortic valve was performed in 83 patients (REP), remodeling of the aortic valve in 175 patients (REMO). The demographics of the two groups were comparable (REP: mean age 54.4 +/- 20.7 yrs, male-female ratio 2.1 : 1; REMO: mean age 60.8 +/- 13.6 yrs, male-female ratio 2.4 : 1; p = ns). In both groups the number of bicuspid valves was comparable (REP: 41 %, REMO: 32 %; p = ns). All patients were followed by echocardiography for a cumulative follow-up of 8204 patient months (mean 32 +/- 23 months).

RESULTS

Overall in-hospital mortality was 2.4 % in REP and 4.6 % in REMO ( p = 0.62). Systolic gradients were comparable in both groups (REP: 5.8 +/- 2.2, REMO: 6.5 +/- 3.1 mm Hg, p = 0.09). The mean degree of aortic regurgitation 12 months postoperatively was 0.8 +/- 0.7 after REP and 0.7 +/- 0.7 after REMO ( p = 0.29). Freedom from significant regurgitation (> or = II degrees ) after 5 years was 86 % in REP and 89 % in REMO ( p = 0.17). Freedom from re-operation after 5 years was 94.4 % in REP and 98.2 % in REMO ( p = 0.33).

CONCLUSIONS

Aortic regurgitation without concomitant root dilatation can be treated effectively by aortic valve repair. The functional results are equivalent to those obtained with valve-preserving root replacement. Aortic valve repair appears to be an alternative to valve replacement in aortic regurgitation.

Validation of sperm sexing in the cattle (Bos taurus) by dual colour fluorescence in situ hybridization

Separation of X- and Y-bearing sperm cells, together with artificial insemination using sex-specific semen, makes it possible to pre-determine the sex of calves. This has the potential to considerably improve cattle breeding, genetic resource management and particularly the efficiency of dairy and meat production. However, the broad use of sexed semen will depend on availability, price, fertilizability and in particular the actual sorting purity of sperm doses. To validate the accuracy of sperm sexing in Bos taurus, we have developed a simple, fast and reliable dual colour fluorescence in situ hybridization (FISH) test, where Y-bearing spermatozoa are identified by a DNA fragment hybridizing to a large pericentromeric repetitive DNA block on the bovine Y chromosome (locus DYZI, Yp13-q12). To avoid an underestimation of Y signals, we used a second DNA probe identifying a large subcentromeric block of complex repetitive DNA on the bovine autosome 6 (locus D6Z1, 6q12-15) as a positive control. Bovine sperm were fixed with methanol:acetic acid and denatured by simply immersing in 3 M NaOH, yielding consistent hybridization results and good preservation of sperm morphology. The FISH protocol was evaluated on unsorted sperm as well as on sperm samples sexed using the Beltsville technology, which separates X- and Y-bearing spermatozoa by staining with Hoechst 33342 and flow sorting according to their DNA content (Johnson et al. 1987).

Heating and humidifying of carbon dioxide during pneumoperitoneum is not indicated

BACKGROUND

Carbon dioxide (CO2) pneumoperitoneum usually is created by a compressed gas source. This exposes the patient to cool dry gas delivered at room temperature (21 degrees C) with 0% relative humidity. Various delivery methods are available for humidifying and heating CO2 gas. This study was designed to determine the effects of heating and humidifying gas for the intraabdominal environment.

METHODS

For this study, 44 patients undergoing laparoscopic Roux-en-Y gastric bypass were randomly assigned to one of four arms in a prospective, randomized, single-blinded fashion: raw CO2 (group 1), heated CO2 (group 2), humidified CO2 (group 3), and heated and humidified CO2 (group 4). A commercially available CO2 heater-humidifier was used. Core temperatures, intraabdominal humidity, perioperative data, and postoperative outcomes were monitored. Peritoneal biopsies were taken in each group at the beginning and end of the case. Biopsies were subjected staining protocols designed to identify structural damage and macrophage activity. Postoperative narcotic use, pain scale scores, recovery room time, and length of hospital stay were recorded. One-way analysis of variance (ANOVA) and the nonparametric Kruskal-Wallis test were used to compare the groups.

RESULTS

Demographics, volume of CO2 used, intraabdominal humidity, bladder temperatures, lens fogging, and operative times were not significantly different between the groups. Core temperatures were stable, and intraabdominal humidity measurements approached 100% for all the patients over the entire procedure. Total narcotic dosage and pain scale scores were not statistically different. Recovery room times and length of hospital stay were similar in all the groups. Only one biopsy in the heated-humidified group showed an increase in macrophage activity.

CONCLUSIONS

The intraabdominal environment in terms of temperature and humidity was similar in all the groups. There was no significant difference in the intraoperative body temperatures or the postoperative variable measured. No histologic changes were identified. Heating or humidifying of CO2 is not justified for patients undergoing laparoscopic bariatric surgery.

Conclusions and activities of previous expert groups: the Scientific Steering Committee of the EU

In 1998, the EU Commission consulted its Scientific Steering Committee (SSC) to give advice on actions against anti-microbial resistance based on scientific evidence. The SSC set up a working group and adopted in 1999 an Opinion on Antimicrobial Resistance. Statements given in the well-structured document are clear, and precise recommendations were proposed. Summarizing, the Committee stated: There is evidence to suppose a continuous flow of resistance genes between pathogenic and commensal bacteria and of transfer of these bacteria between different compartments of the biosphere, thus changing the genetic resources continuously. There exist numerous factors which influence the emergence and spread of anti-bacterial resistance. However, it is likely that restriction in the use of anti-microbials will lead to a containment or a reduction of the drug resistance problem. Actions should be taken promptly to reduce the overall use of anti-microbials in a balanced way in all areas: human medicine, veterinary medicine, animal production and plant protection.

[The perception of veterinary medicine in the print media]

Between January 2000 and October 2003, a print media data bank on published contributions was screened for the German key words "Tierarzt/Tierärztin" and "Veterinär/Veterinärin" (veterinary surgeon) and related items. 267 articles have been found. Regarding the contents, the articles were characterised according to the content (VPH, surgeons, other), and the cause of the article. Regarding the surgeon part, mostly companion animals are dealt with. If it comes to VPH, primarily so called scandals such as misuse of therapeuticals or epidemics (BSE, FMD) have been reported. In the first instance these articles reflect only a temporary interest, and they do not give real insight into the daily work of the profession. As a consequence, public intelligence on veterinary medicine may be misled by such press articles, possibly generating wrong expectations in young people who might start with veterinary medicine. Institutional bodies should provide information, which covers the subject in a more realistic way in order to prevent a wrong understanding of the profession and to offer the whole scope of the public functions of veterinary medicine.

Influence of methods for Trichinella detection in pigs from endemic and non-endemic European region

A total of 1401 German and 226 Croatian pigs raised either indoors or outdoors were tested for Trichinella infection by direct and indirect detection methods. A 10 g sample of diaphragm were examined for muscle larvae by the artificial digestion method; the species was determined by multiplex polymerase chain reaction (PCR). For detection of anti-Trichinella IgG, serum samples diluted 1:100, and meat juice samples diluted 1:10, were tested by enzyme-linked immunosorbent assay. All German pigs and those Croatian pigs raised indoors proved to be Trichinella-negative by all methods. Muscle larvae were detected in a total of eleven of the Croatian pigs, which were raised on small outdoor farms. For eight isolates, PCR results demonstrated that recovered larvae were Trichinella spiralis. Anti-Trichinella-IgG was detected in serum and meat juice of digestion positive animals when the worm burdens exceeded 0.38 larvae per gram of muscle. Positive results in Croatian pigs indicate a higher risk of infection for outdoor farming in areas where Trichinella is endemic. Results of direct and indirect detection were compared and are discussed with special regard to specificity and sensitivity of methods.