Journal of Veterinary Research最新文献

Introduction: Blastocystis spp. is a common anaerobic intestinal parasite infecting humans and a diverse range of animals. The aim of the study was to compare different diagnostic methods for the detection of Blastocystis and survey the occurrence of its subtypes in farm animals, namely sheep, cows and camels, in Al-Ain, United Arab Emirates.

Material and methods: Ninety-seven faecal samples comprised of 69 from sheep, 12 from cows and 16 from camels were submitted to DNA extraction, PCR and sequencing. Blastocystis was screened for microscopically in 65 samples using direct wet-mount, modified acid-fast staining, trichrome staining and in vitro culture techniques.

Results: Fifteen (15.5%) samples were positive by PCR, twelve of which were confirmed by sequencing. Using PCR as a comparison standard, the sensitivity and specificity of the direct wet-mount, modified acid-fast staining, trichrome staining and in vitro culture methods were 40.0% and 78.3%, 40.0% and 83.3%, 80.0% and 80.0%, and 80.0% and 76.7% respectively. Only culture and trichrome tests were significantly associated with PCR (odds ratio (OR) = 13.14; 95% confidence interval (CI): 1.35-127.4; P = 0.007 and OR = 16; 95% CI: 1.63-156.5; P = 0.003, respectively) with trichrome detecting more positive cases than in vitro culture. The subtype (ST)10 was the only one found in all 12 sequenced sheep isolates.

Conclusion: The study corroborated previous data indicating that sheep are the natural hosts for ST10. No zoonotic subtypes nor mixed-subtype colonisation were found. The report also confirmed the superiority of trichrome staining in detecting Blastocystis spp.

Introduction: Escherichia coli is the most common pathogen isolated from the urine of dogs with urinary tract infections (UTIs). While there are many studies in humans investigating the potential for the prevention of UTIs by dietary consumption of cranberry, few analogous studies have been carried out in dogs.

Material and methods: Eight dogs, four male and four female, were successively fed two diets, first a control without cranberry, and then the second diet containing cranberry extracts. Naturally excreted urine was collected on the tenth day after the start of each diet for 24 h and used for bacterial growth. Madin-Darby canine kidney cell adherence by the uropathogenic E. coli G1473 strain expressing type 1 pili and positive for P pili and haemolysin gene markers was quantified after growth in urine samples.

Results: Significant reductions in bacterial adherence to MDCK cells (from -16.5 to -73.4%, P < 0.05) were observed in the four females but not in the males after consumption of the cranberry extracts compared to the same animals consuming the control diet.

Conclusion: Dietary supplementation with cranberry may provide some degree of protection to female dogs against adhesion of uropathogenic E. coli to urinary epithelial cells.

Introduction: Rodents are quite common at livestock production sites. Their adaptability, high reproductive capacity and omnivorousness make them apt to become a source of disease transmission to humans and animals. Rodents can serve as mechanical vectors or active shedders of many bacteria and viruses, and their transmission can occur through direct contact, or indirectly through contaminated food and water or by the arthropods which parasitise infected rodents. This review paper summarises how rodents spread infectious diseases in poultry production.

Material and methods: The aim of this review was to use PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) principles to meta-analyse the available data on this topic. Three databases - PubMed, Web of Science and Scopus - and grey literature were searched for papers published from inception to July 2022 using the established keywords.

Results: An initial search identified 2,999 articles that met the criteria established by the keywords. This number remained after removing 597 articles that were repeated in some databases. The articles were searched for any mention of specific bacterial and viral pathogens.

Conclusion: The importance of rodents in the spread of bacterial diseases in poultry has been established, and the vast majority of such diseases involved Salmonella, Campylobacter, Escherichia coli, Staphylococcus (MRSA), Pasteurella, Erysipelothrix or Yersinia infections. Rodents also play a role in the transmission of viruses such as avian influenza virus, avian paramyxovirus 1, avian gammacoronavirus or infectious bursal disease virus, but knowledge of these pathogens is very limited and requires further research to expand it.

Introduction: Whippets are traditionally trained to compete in lure coursing. While in humans and horses, training is routinely monitored by special tests, this is not carried out in the training of whippets. The aim of this study was to check if laboratory tests designed for racehorses could be useful in monitoring whippets training for lure coursing.

Material and methods: Blood samples were taken from 14 whippets at several time points: before exercise (including warm-up), immediately after, 15 min after and 30 min after exercise sessions of straight 400 m runs (T) and coursing (C). Routine haematological values and lactate concentrations (LA) were measured.

Results: White blood cell count, red blood cell count, haemoglobin concentration and haematocrit increased significantly in both types of exertion, and no differences between the types were observed. The LA measured immediately after the run were increased, but there was no significant difference between the types of session (T and C). After both types of activity, LA decreased within 30 min post run by 9-11 mmol/L. Lactate concentrations were significantly higher 30 min after the T sessions than after the C sessions.

Conclusion: The results confirmed that typical exercise-induced changes occurred in whippets training for lure coursing; however, the scale of changes was different to that in horses. The sampling scheme used in racehorses can be applied to whippets and can be useful as a laboratory tool for monitoring their training.

Introduction: Bees are currently artificially inseminated on a large scale for breeding and research purposes. The sperm of bees has a complex and varied structure, and determination of specific morphological defects in it is very difficult. Its comprehensive analysis by inspecting morphology and morphometry is an important tool for improving honey bee lines. The staining technique should interfere with the cells as little as possible while clearly showing the boundaries of the head and other elements. In this study, a comparative analysis of the morphometry of sperm was performed with various techniques for staining drone semen.

Material and methods: Semen was collected from 150 sexually mature Buckfast bee drones by artificially everting the copulatory organ. The morphology and morphometry of the sperm were assessed on slides prepared by three staining methods according to the protocols described online, using the Sperm Class Analyzer system. The lengths of the acrosome, nucleus, head in total, midpiece, tail without midpiece, tail with midpiece, and entire sperm were measured.

Results: The most details of the drone sperm structure could be seen when stained with the eosin-nigrosin complex. This method made it possible to identify all structures and revealed the uneven distribution of sperm proteins in different parts of the tail. With the Sperm Stain method fewer details of the sperm structure were recognisable, and the fewest were with SpermBlue.

Conclusion: The staining method, and thus the chemical reagents used, affect the dimensions of drone sperm. Given the great research potential of modified spermatozoa of insects, a standard for slide preparation for the evaluation of morphological and morphometric semen parameters should be established, as this would facilitate result comparison between laboratories and increase the value of morphological analysis of sperm for predicting and assessing fertility.

Introduction: Among large wild game in Poland, the most numerous cervids are red deer and roe deer. Although these species live free, they should be under veterinary supervision because they can transmit infectious agents and parasites to livestock. The aim of this study was to evaluate the biodiversity of the abomasal nematodes which parasitise cervids and present the visual and dimensional characteristics of their spicules.

Material and methods: Overall, 2,067 spicules of nematodes derived from nine red deer and five roe deer were measured and microphotographed in order to determine the species. The predominant Spiculopteragia boehmi was additionally confirmed molecularly by PCR. The spicule lengths of the most common species found in both hosts simultaneously were compared.

Results: Fourteen species of abomasal nematode were identified. All examined animals but one were infected. The most prevalent parasites in both host species were S. boehmi and Ostertagia leptospicularis. The alien Ashworthius sidemi was found in both hosts, whereas Haemonchus contortus was identified only in red deer. Mazamastrongylus dagestanica was noted in red deer for the first time. A 262-base-pair nucleotide sequence of S. boehmi was obtained and deposited in GenBank. Significantly longer spicules were found in red deer-derived O. leptospicularis and S. boehmi and shorter structures were seen in A. sidemi.

Conclusion: The widespread exchange of abomasal nematodes between various ruminant species questions the relevance of their division into specialists and generalists.

Introduction: Mycotoxins in dairy cows can cause many non-specific symptoms often resulting from immune system overreaction. The study assessed the concentration of selected cytokines and acute phase proteins (APP) in cows with natural mycotoxicosis before and after using a mycotoxin neutraliser. The cytokines were tumour necrosis factor alpha (TNF-α), interleukin 6 (IL-6) and interleukin 10 (IL-10), and the APP were serum amyloid A (SAA) and haptoglobin (Hp).

Material and methods: The research was carried out on an experimental group (Exp) of 10 herdmate Holstein-Friesian cows with mycotoxicosis. The control group (Con) was 10 healthy cows of the same breed from a different herd. Cows in the Exp group were administered the mycotoxin deactivator Mycofix for three months. Blood was drawn from Exp cows once before administering Mycofix and a second time after three months of its use. Blood was also drawn from Con cows at the same times. Serum levels of TNF-α, IL-6, IL-10, SAA and Hp were assessed using ELISA.

Results: The concentrations of all cytokines and Hp in Exp cows were higher before treatment (P < 0.001) than those in Con cows. After three months of administering Mycofix, the concentrations of TNF-α and IL-6 were significantly lower than their pre-treatment levels (P < 0.001). The concentrations of IL-6, IL-10, and Hp were still significantly higher than those in the Con group (P < 0.001). In cows with mycotoxicosis, simultaneous stimulation of antagonistic processes was noted: a pro-inflammatory process in the upregulation of TNF-α and IL-6, and an anti-inflammatory one in the upregulation of IL-10.

Conclusion: Despite the absorbent's use and the resolution of clinical symptoms in Exp cows, high levels of IL-10 and Hp and IL-6 were maintained. Assessment of the level of cytokines and APP appears to be a useful and precise tool for the evaluation and application of the appropriate dose of the mycotoxin absorbent or the evaluation of its effectiveness.

Introduction: Mycobacterium bovis and Mycobacterium avium subsp. paratuberculosis, respectively the causative agents of bovine tuberculosis (bTB) and bovine paratuberculosis (PTB), share a high number of antigenic proteins. This characteristics makes the differential diagnosis of the diseases difficult. The interferon gamma (IFN-γ), C-X-C motif chemokine ligand 10 (CXCL10), matrix metallopeptidase 9 (MMP9), interleukin 22 (IL-22) and thrombospondin 1 (THBS1) bovine genes have already been shown to be accurate transcriptional biomarkers of bTB. In order to improve the diagnosis of bTB and PTB, in the present study we evaluated the risk of false positivity of these bTB biomarkers in cattle with PTB.

Material and methods: The transcription of these genes was studied in 13 PTB-infected cattle, using Mycobacterium avium subsp. paratuberculosis (MAP)-stimulated peripheral blood mononuclear cells (PBMC).

Results: Overall, the levels of IFN-γ, CXCL10, MMP9 and IL-22 transcripts in MAP-stimulated PBMC failed to differentiate animals with PTB from healthy animals. However, as bTB-afflicted cattle do, the MAP-infected group also displayed a lower level of THBS1 transcription than the non-infected animals.

Conclusion: The results of this study add new specificity attributes to the levels of transcription of IFN-γ, CXCL10, MMP9 and IL-22 as biomarkers for bTB.

Introduction: Bovine adenovirus (BAdV) type 3 causes respiratory and gastroenteric diseases of varying severity in cattle, particularly newborn calves. Trials have been conducted of a vaccination against the diseases caused by BAdV using both modified live-virus and inactivated-virus preparations in cattle, but no commercial BAdV-3 vaccine has yet reached the market. Therefore, there is an urgent need to develop new, safe, and effective vaccines against BAdV-3.

Material and methods: Recombinant hexon protein (rhexon) of BAdV-3 was expressed in the E. coli system to evaluate immune response in mice and goats. Antibody responses and cytokine levels were analysed and the effects of administrations of different amounts of recombinant protein compared. Long-term antibody production was evaluated by indirect ELISA, and the total immunoglobulin G secreted by goats and mice immunised with the purified rhexon protein was determined.

Results: The immunised mice had a stronger antibody response than the control group at eight weeks post vaccination. The immunised groups also showed significantly higher (P ˂ 0.05) expression of interferon-γ, interleukin 2 (in mice), and interleukin 21 (in goats) at four weeks. Furthermore, vaccination with rhexon was able to induce long-term antibody production for at least 16 weeks in mice and goats.

Conclusion: The rhexon protein induced immune responses, especially long-term antibody production and T helper 1 cell cytokine production in mice and goats. The immunogenic properties of this protein make it a promising subunit vaccine antigen.

Introduction: Bovine viral diarrhoea virus (BVDV) and bovine herpesvirus (BoHV)-1 and -4 are important causes of respiratory diseases and reproductive disorders of dairy cattle worldwide.

Material and methods: Investigation of BVDV and BoHV-1 and -4 antibody levels in the serum and milk of dairy cattle in a group with clinical mastitis and a healthy group was undertaken using an indirect ELISA, and identification of the BoHV-4 genotypes in clinical mastitis cases was attempted by PCR and sequencing.

Results: Antibodies specific to BVDV, BoHV-1 and BoHV-4 were detected in the serum and milk of all dairy cattle with clinical mastitis. The cut-off values for BVDV and BoHV-1 in the sera and milk were extremely high in both healthy and mastitic animals. However, BoHV-4 antibodies were detected only in the clinically mastitic cattle, and BoHV-4 levels were higher in milk than in sera among these animals. Genotypes I and II of BoHV-4 were detected in the milk samples of four seropositive cows with clinical mastitis from the same herd.

Conclusion: The results of this investigation demonstrate that clinical mastitis cases in the same herd may have aetiology in different BoHV-4 genotypes.