Status of prooxidant and antioxidant systems in the sperm and seminal plasma of breeding boars of large white breed and SS23 synthetic line.

The indicators of pro- and antioxidant systems in sperm and sperm plasma of breeding boars of Large White breed and SS23 synthetic line were studied. Measurements of antioxidant enzyme activity, determination of lipid peroxidation (LPO) product content, and antioxidant factor were performed. Lipid peroxidation in the semen of healthy breeding boars was characterized by a stable level of activity, which is necessary to ensure normal reproductive functions. Additionally, there was a high content of low molecular weight thiols and proteins. The concentration of SH-groups in spermatozoa was higher (P≤0.05) compared to sperm plasma. The number of total, protein, and free SH-groups in the semen of boars of the synthetic line was higher (P<0.05) in relation to animals of the Large White breed. Low catalase (CAT) activity in the sperm was compensated by glutathione peroxidase (GPX). The content of ceruloplasmin (CP) in the sperm of boars was almost twice as high as that of sperm plasma. In spermatozoa, high content of reduced glutathione (GTH) was recorded, which was more than 3 times higher than in the seminal fluid. The main antioxidants of spermatozoa were superoxide dismutase (SOD), CP, SH-groups of proteins, and reduced content of GTH. We revealed that CAT is a key enzyme that neutralizes excess hydrogen peroxide in boar semen. In contrast, in sperm, hydrogen peroxide was inactivated mainly by GPX. Further research on the mechanisms of action of reactive oxygen species on boar semen will help to develop effective methods for sperm storage and successful fertilization of oocytes.

The meaning of non-classical estrogen receptors and peroxisome proliferator-activated receptor for boar Leydig cell of immature testis.

Communication in biological systems involves diverse-types of cell-cell interaction including cross-talk between receptors expressed by the target cells. Recently, novel sort of estrogen receptors (G protein - coupled estrogen receptor; GPER and estrogen-related receptor; ERR) that signal directly via estrogen binding and/or via mutual interaction-regulated estrogen signaling were reported in various organs including testis. Peroxisome proliferator - activated receptor (PPAR) is responsible for maintaining of lipid homeostasis that is critical for sex steroid production in the testis. Here, we investigated the role of interaction between GPER, ERRß and PPARγ in steroidogenic Leydig cells of immature boar testis. Testicular fragments cultured ex vivo were treated with GPER or PPARγ antagonists. Then, cell ultrastructure, expression and localization of GPER, ERRß, PPARγ together with the molecular receptor mechanism, through cyclic AMP and Raf/Ras/extracellular signal activated kinases (ERK), in the control of cholesterol concentration and estrogen production by Leydig cells were studied. In the ultrastructure of antagonist-treated Leydig cells, mitochondria were not branched and not bifurcated as they were found in control. Additionally, in PPARγ-blocked Leydig cells changes in the number of lipid droplets were revealed. Independent of used antagonist, western blot revealed decreased co-expression of GPER, ERRß, PPARγ with exception of increased expression of ERRß after PPARγ blockage. Immunohistochemistry confirmed presence of all receptors partially located in the nucleus or cytoplasm of Leydig cells of both control and treated testes. Changes in receptor expression, decreased cholesterol and increased estradiol tissue concentrations occurred through decreased cAMP level (with exception after GPER blockage) as well as Raf/Ras/ERK pathway expression. These all findings indicate that GPER-ERRß-PPARγ interaction exists in immature boar testis and regulates Leydig cell function. Further detailed studies and considerations on GPER-ERRß-PPARγ as possible diagnosis/therapy target in disturbances of testis steroidogenic function are needed.

Expression of goose parvovirus whole VP3 protein and its epitopes in Escherichia coli cells.

The aim of this study was the expression of goose parvovirus capsid protein (VP3) and its epitopes in Escherichia coli cells. Expression of the whole VP3 protein provided an insufficient amount of protein. In contrast, the expression of two VP3 epitopes (VP3ep4, VP3ep6) in E. coli, resulted in very high expression levels. This may suggest that smaller parts of the GPV antigenic determinants are more efficiently expressed than the complete VP3 gene.

Incidence of parvoviruses in chickens infected with Marek's disease virus.

The aim of the study was to determine co-occurrence of Marek's disease virus (MDV) and chicken parvovirus (ChPV) co-occurrence in field chicken flocks. The materials for the study derived from 115 broiler chickens or layer hens originated from 23 farms with suspicion of Marek's disease (MD). Dual infection with MDV and ChPV was found in 23 (20%) examined chickens. The results obtained suggest a possibility of influence of ChPV infection on efficacy of the MD vaccines.

Canine intestinal spirochetes consist of Serpulina pilosicoli and a newly identified group provisionally designated "Serpulina canis" sp. nov.

The spirochetes inhabiting the large intestines of humans and animals consist of a diverse group of related organisms. Intestinal spirochetosis caused by Serpulina pilosicoli is a newly recognized enteric disease of human beings and animals with potential public health significance. The purpose of this study was to determine the species identity of canine intestinal spirochetes by comparing 30 isolates obtained from dogs in Australia (n = 25) and the United States (n = 5) with reference strains representing Serpulina species and Brachyspira aalborgi, by phenotypic and genetically based typing methods. All of the canine isolates were indole negative and produced a weak beta-hemolysis when cultured anaerobically on agar medium containing blood. Four isolates were identified as S. pilosicoli by 16S rRNA-specific PCR assays, rRNA gene restriction fragment length polymorphism or ribotyping, and multilocus enzyme electrophoresis. The remaining 26 isolates formed a cluster related to porcine Serpulina innocens as determined by multilocus enzyme electrophoresis but had a unique ribotype pattern. The data suggested the existence of a novel Serpulina species, provisionally designated "Serpulina canis," colonizing the intestines of dogs.

Chromosome sizes and phylogenetic relationships between serotypes of Actinobacillus pleuropneumoniae.

The genome size of Actinobacillus pleuropneumoniae was determined by pulsed field gel electrophoresis of AscI and ApaI digested chromosomal DNA. The genome size of the type strain 4074T (serotype 1) was determined to be 2404 +/- 40 kb. The chromosome sizes for the reference strains of the other serotypes range between 2.3 and 2.4 Mb. The restriction pattern profiles of AscI, ApaI and NheI digested chromosomes showed a high degree of polymorphism among the different serotype reference strains and allowed their discrimination. The analysis of the macrorestriction pattern polymorphism revealed phylogenetic relationships between the different serotype reference strains which reflect to some extent groups of serotypes known to cross-react serologically. In addition, different pulsed fields gel electrophoresis patterns also revealed heterogeneity in the chromosomal structure among different field strains of serotypes 1, 5a, and 5b, while strains of serotype 9 originating from most distant geographical places showed homogeneous ApaI patterns in pulsed field gel electrophoresis.

Evaluation of different vaccines to control of pig colibacillosis under large-scale farm conditions.

The aim of the study was to evaluate, under large-scale farm conditions, the prophylactic effect of various inactivated E. coli vaccines in the control of pig colibacillosis. The investigations were carried out with 2472 pregnant sows, immunized with 8 different vaccines containing E. coli fimbrial adhesins and adjuvants. Efficacy of the biologicals used was tested by evaluation of the health state of the newborn piglets, i.e. number of born and weaned piglets, percentage of piglets with diarrhea and dead piglets, and mean body weight gain of weaned piglets. It was also intended to check the influence of immunization on the number of pathogenic E. coli strains in the faeces of piglets originating from the vaccinated sows. The vaccines used in the study differed in their protective effect but all of them had a positive influence on the health status of the newborn piglets as well as on the reduction in the faeces of the number of pathogenic E. coli isolates. The best results were obtained when pregnant sows were immunized with a vaccine containing purified K88, K99, and 987P fimbriae and B subunit of LT enterotoxin. It seems that the determination of the number of pathogenic E. coli strains in the faeces of piglets originated from dams vaccinated against colibacillosis can be helpful in the evaluation of the vaccine efficacy.

Efficacy of an Actinobacillus pleuropneumoniae bacterin against serotypes 1, 3, 5 and 9.

A trial was performed in a swine research facility to ascertain the protection provided by a polyvalent Actinobacillus pleuropneumoniae (APP) bacterin containing serotypes 1, 3, 5 and 9. The test animals consisted of 60, eight-week-old, piglets, which were randomly divided into four main groups. The four main groups were further divided into three sub-groups (I, II, III) of five pigs each. Subgroup I was vaccinated intramuscularly, sub-group II was vaccinated subcutaneously, and sub-group III served as the unvaccinated control group. Each main group was challenged with a single APP serotype (1, 3, 5 or 9). Criteria for evaluation of the bacterin efficacy were mortality, lung lesions, pleural adhesions, and isolation of APP from tonsil or lung. Significant effects of vaccination over nonvaccination were reduced mortality, lung lesions, pleural adhesions, and isolations of APP from tonsil and lung. There were no significant differences between the intramuscular and subcutaneous routes of vaccination. It was concluded that the four-way APP bacterin used in this study provided satisfactory protection against homologous challenge. Evidence of protection was lower mortality and lung lesions and increased daily weight gains in vaccinates as compared with controls.

The occurrence of endotoxin in sows with coliform mastitis.

The purpose of this study was to determine the role of endotoxins in the etiology of coliform mastitis /CM/ in sows under field conditions, by using the Limulus amebocyte lysate /LAL/ test for the detection of endotoxins in the blood of pigs. For this purpose, blood samples from 40 healthy sows and 46 sows with clinical signs of CM were drawn once between 24 and 72 h post partum and tested accordingly. Only one clinically healthy sow 2.5% showed the presence of endotoxins in the serum. In sows clinically affected with one or more symptoms of the CM, the bacterial toxins were detected in 15 cases /32.5%/. The results of these studies support the observation that in only a certain percentage of all CM cases the occurrence of endotoxin in blood can be shown. Sampling time in relation to the occurrence of clinical symptoms and sampling frequency may have had an influence on the detectability of circulating endotoxins. Consequently, not all cases with endotoxemia may have been identified. The usefulness of the LAL test for endotoxin detection in the blood of pigs was confirmed.