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Abstract

Introduction

Repeated incursions of highly pathogenic avian influenza virus (HPAIV) H5 subtype of Gs/GD lineage pose a serious threat to poultry worldwide. We provide a detailed analysis of the spatio-temporal spread and genetic characteristics of HPAIV Gs/GD H5N8 from the 2019/20 epidemic in Poland.

Material and methods

Samples from poultry and free-living birds were tested by real-time RT-PCR. Whole genome sequences from 24 (out of 35) outbreaks were generated and genetic relatedness was established. The clinical status of birds and possible pathways of spread were analysed based on the information provided by veterinary inspections combined with the results of phylogenetic studies.

Results

Between 31 December 2019 and 31 March 2020, 35 outbreaks in commercial and backyard poultry holdings and 1 case in a wild bird were confirmed in nine provinces of Poland. Most of the outbreaks were detected in meat turkeys and ducks. All characterised viruses were closely related and belonged to a previously unrecognised genotype of HPAIV H5N8 clade 2.3.4.4b. Wild birds and human activity were identified as the major modes of HPAIV spread.

Conclusion

The unprecedentedly late introduction of the HPAI virus urges for re-evaluation of current risk assessments. Continuous vigilance, strengthening biosecurity and intensifying surveillance in wild birds are needed to better manage the risk of HPAI occurrence in the future.

Abstract

Introduction

Marek’s disease (MD) is a tumourous disease caused by Marek’s disease virus (MDV) and most commonly described in poultry. The aim of the study was to determine the occurrence of Marek’s disease virus infections in Poland and analyse clinical cases in the years 2015–2018.

Material and Methods

The birds for diagnostic examination originated from 71 poultry flocks of various types of production. Birds were subjected to anatomopathological examination post mortem, during which liver and spleen sections and other pathologically changed internal organs were taken. These sections were homogenised with generally accepted methods, then total DNA was isolated and amplified with a real-time PCR. A pair of primers complementary to the MDV genome region encoding the meq gene were used.

Results

MDV infection was found predominantly in broiler chicken flocks (69.01%), and also in layer breeder (9.85%) and commercial layer flocks (7.04% each).

Conclusion

The results of research conducted in the years 2015–2018 clearly indicate that the problem of MDV infections is still current.

Abstract

Introduction

Snail eggs can be the raw material for the production of a caviar substitute. The substitute varies from the original in caloric value and nutrient content which determine the nutritional value of every foodstuff. The present study aimed to determine and compare the nutritional value and protein quality of eggs from two subspecies of edible snail.

Material and Methods

The chemical composition of the snail eggs i.e. Cornu aspersum maxima and Cornu aspersum aspersum was determined in accordance with international standards. In order to evaluate the protein quality of the eggs of the two studied snail subspecies, the chemical score (CS), and a reference protein were used.

Results

Significant differences in the content of water, ash, and carbohydrates, but comparable protein and fat contents and caloric values were found.

Conclusion

The protein in the eggs of the snails was complete by the measure of the model adopted for this study, however, meeting the daily essential amino acid requirements of an adult would require an immense supply of both species’ eggs. Snail eggs of the Cornu genus were characterised by much lower nutritional value in comparison with caviar and caviar substitutes.

Abstract

Introduction

Canine parvovirus type-2 (CPV-2) causes acute infectious diseases in puppies, which show high morbidity and mortality. Better effect of vaccination against these diseases could be achieved with deeper knowledge of CPV-2 genotype dissemination and mutation history. This study investigated CPV-2–positive samples collected recently over a wide region of China.

Material and Methods

A total of 118 faecal samples from dogs identified as CPV-positive were collected from veterinary clinics in central and eastern China. Overall, 16 strains collected from Anhui, 29 from Henan, and 16 from Zhejiang Province were sequenced to determine the genotypic composition of CPV-2 and mutational complexity of CPV-VP2.

Results

The CPV-2a, CPV-2b, and CPV-2c genotypes were detected in Anhui and Henan Provinces, while CPV-2c alone was detected in Zhejiang Province. Sequence analysis of all strains showed 98.5%–99.8%, 98.3%–99.9%, and 98.7%–99.8% identity among the 16 Anhui, 29 Henan, and 16 Zhejiang strains, respectively. Strains collected from Anhui and Henan Provinces showed lower identity (97.0%), suggesting greater genetic divergence in central China. The mutation rates of Henan and Anhui strains were lower than that of Zhejiang strains. Major amino acid mutations occurred at sites 5, 370, 426, and 440. Epitope and entropy analyses implied these sites’ likely conformance to the principles of mutation tendency, complexity, and diversity.

Conclusion

The findings for the evolutionary structure of CPV-2 strains collected from three provinces in central and eastern China advance trend monitoring of the genetic variation in canine parvovirus and point to its implications in the development of novel vaccines.

Abstract

Introduction

Candida species are a natural component of the intestinal tract microflora, but in favourable conditions they can cause superficial, mucosal, or even systemic candidiasis. Poultry production might be a source of human drug-resistant yeast infections, including Candida spp. The limited data concerning the antifungal susceptibility of poultry Candida isolates prompted us to carry out research to determine the susceptibility of isolates from turkey intestinal tracts.

Method and Materials

The beak cavity, crop and cloaca were swabbed of 580 turkeys from 58 flocks in western Poland. The susceptibility tests were conducted using the E-test method with amphotericin B, fluconazole, itraconazole, and voriconazole on 52 isolates of C. albicans, C. catenulata, C. glabrata, C. palmioleophila, C. rugosa, C. krusei and C. lusitaniae.

Results

All isolates were susceptible to voriconazole. According to the MIC values obtained for amphotericin B and fluconazole, all Candida spp. isolates were classified as susceptible according to the described breakpoints except for C. krusei, which was the only isolate that was amphotericin B-, fluconazole- and itraconazole-resistant. The susceptibility to itraconazole varied: 11 of the Candida isolates were susceptible (21.1%), 29 were dose-dependently susceptible (55.8%), and 12 isolates were resistant (23.1%).

Conclusion

There are few resistant strains of Candida in turkeys, and the drug resistance varies. When Candida passes from turkeys to humans, there is a wide range of antifungal treatment options.

Abstract

Introduction

The influence of inflammation on the patterns of muscarinic 2 and 3 receptor subtypes (M2R and M3R), and α-7 nicotinic acetylcholine receptor (α-7 nAChR) expression in the porcine uterus was investigated.

Material and Methods

On day three of the oestrous cycle of gilts aged 7–8 months with body weight 90–120 kg, either an E. coli suspension (E. coli group, n = 5) or saline (Sal group, n = 5) was administered into the uterine horns via laparotomy or only laparotomy was performed on control swine (Ctrl group, n = 5). After eight days, and the onset of severe acute endometritis in the E. coli group, the uterine mRNA and protein receptor expression levels were determined using real-time RT-PCR and Western blotting, respectively, with receptor localisation by immunofluorescence.

Results

The studied receptors were in the luminal epithelium, glands, blood vessels, and myometrial muscle cells of all gilts. The M2R mRNA level was lower in the inflamed endometrium compared to the Ctrl and Sal groups. Also in this tissue, the expression of M3R mRNA and protein was lower than in the Ctrl and Sal groups. The M3R protein level in the bacterially challenged myometrium was found to be increased compared to unadministered groups. In the endometrium of the E. coli group, the α-7 nAChR protein level was lower than in the Sal group, and in the myometrium it was reduced in relation to both the other groups. P values were ≤ 0.05 in all cases.

Conclusion

Inflammation causes alterations in the M2R, M3R, and α-7 nAChR expression in the pig uterus, suggesting their significance in the course and repercussions of uterine inflammation.

Abstract

Introduction

Three strains of the FMD virus (A, O, and SAT 2) were recognised as causes of the FMD circulating in Egypt. The aims of this study were to trace the FMDV isolates from outbreaks in Egypt to understand their epidemiology and evolution and to understand the situation of the vaccine strains compared with the circulating serotypes.

Material and Methods

A meta-analysis was carried out by using the data available for FMD outbreaks in Egypt from GenBank and the World Reference Laboratory for Foot-and-Mouth Disease (WRLFMD); a comparison was done with both data sets for the three serotypes. MEGA-X was used for the evolution analysis, through constructions of phylogenetic trees for all sequences recorded in GenBank for each serotype in different Egyptian outbreaks in different years and also within the same year. Additionally, nucleotide substitution rate, molecular clock, and mean evolutionary rates were estimated for the three serotypes to understand and compare their evolution.

Results

Absence of some records of certain serotype outbreaks from the WRLFMD database was noted as were subsequent missing appropriate vaccine programmes. Genetic variation was recorded among the virus isolates within the same years and also the vaccine strain was associated with up to 26 amino acid substitutions. The evolution rate of the SAT2 strain was the highest of the circulating strains. SAT2 had high amino acid substitution per year at an important immunogenic site (130–170), serotype A had less, and serotype O the least.

Conclusion

The need for different strategies for vaccine serotype selection is indicated.

Abstract

Introduction

Gastrointestinal parasites are some of the most common pathogens which are seriously harmful to the camel’s health. The infection status of gastrointestinal parasites in camels (Camelus bactrianus) in the Tianshan Mountains pastoral area in China is still unclear. The aim of this study was to investigate the species and infection intensity of gastrointestinal tract parasites in local camels.

Material and Methods

A total of 362 fresh faecal samples were collected and examined for parasite eggs using the saturated saline floating and natural sedimentation method. The parasite eggs were subjected to morphological and molecular examination and identification, and the infection rate and mean intensity of the parasites were analysed.

Results

A total of 15 gastrointestinal tract parasite species’ eggs were identified, with a detection rate of 100%. Ostertagia spp. (100%) and Trichostrongylus spp. (98.1%) were dominant. Camels were often coinfected by 5–14 species. The average number of eggs per gram of faeces was higher for Ostertagia spp. (298), Haemonchus contortus (176) and Nematodirus spp. (138). The number of species of parasites infecting young camels was significantly lower than that of adult camels, but the infection intensity in young camels was significantly higher.

Conclusion

Gastrointestinal parasites were highly prevalent in camels from the Tianshan Mountains pastoral area in China. This finding provides important epidemiological data for the prevention and control of associated infections in camels.

Abstract

Introduction

The aim of the study was to determine the effect of the vitamins, omega-3 polyunsaturated fatty acid and minerals in the supplement Toryum administered before and during oestrus synchronisation on some fertility parameters of ewes during the non-breeding season.

Material and Methods

The experimental animals were clinically healthy Pirlak ewes, 55–75 days postpartum, aged 2–4 years and weighing 40–50 kg. A sponge was inserted into the vagina for 10 d (G1, n = 30; G2, n = 30) or 14 d (G3, n = 30; G4, n = 30) for oestrus synchronisation, and on the day of removal, 400 IU equine chorionic gonadotropin was injected. Toryum soft capsules were administered individually (1 capsule/ewe p.o.) to G1 and G3 ewes seven days before the sponge was inserted and on the day it was removed. Oestrus detection was started 12 h after sponge removal. Pregnancy was diagnosed by transrectal ultrasonography on the 30th day after mating.

Results

The pregnancy rate was statistically different between G1 and G4 (P < 0.05). The onset of oestrus was statistically different (P < 0.001) between the 10-d groups (G1 and G2) and the 14-d groups (G3 and G4). The litter size and oestrus, conception, lambing, multiple birth, and survival rates were not significantly different between the groups (P > 0.05).

Conclusion

Toryum administered to Pirlak ewes during progesterone-based oestrus synchronisation protocols during the non-breeding season may increase pregnancy rates. The relationship between Toryum and fertility parameters in ewes would be better understood by comprehensive studies.

Abstract

Introduction

Silage quality deteriorates with Clostridium spp. contamination, and if consumed, such silage jeopardises herd health and productivity. Minimising its occurrence reduces economic and animal welfare risks. The study investigated the influence of environmental and technological determinants on the Clostridium genus’ occurrence in silage.

Material and Methods

Analyses were conducted on 305 silage samples directly collected from farms located in all Polish provinces. Cultures and isolates were evaluated phenotypically and examined for occurrence of Clostridium spp., particularly C. perfringens and C. botulinum using PCR techniques. The results were statistically analysed using the ᵡ2 test for continuous and Student’s t-test for non-continuous values.

Results

The most influential effect on Clostridium spp. occurrence is exerted by factors potentially associated with primary production, like the type of fertilisation and the contamination level of the ensiled feed material. Clostridium spp. was detected in 232 (76%) samples, and C. perfringens strains, predominantly toxinotype A, in 79 (26%). C. botulinum occurrence was not detected.

Conclusions

Deterioration of silage by clostridia could be prevented by a properly conducted ensiling process with the addition of starter cultures, but the presence of spores mainly depends on primary production and the extent of contamination of the feed material.