Journal of Veterinary Research最新文献

Introduction: Campylobacter are the most common cause of food poisoning, which manifests itself in diarrhoea of varying severity. Additionally, because of the increasing number of people with immune deficiencies, more frequent serious complications of Campylobacter infections are being observed. The main source of infection is the consumption of contaminated poultry meat, which is a consequence of the insufficiency of current hygiene and biosecurity to control Campylobacter or eliminate it from the poultry food chain.

Material and methods: Two hybrid proteins, presenting selected epitopes of the Campylobacter antigens CjaD and EF-Tu, were developed based on the highly immunogenic proteins CjaA and CjaC. Four groups of chickens were vaccinated with different preparations (a mixture of both hybrid proteins encapsulated in anionic or neutral liposomes) and different doses (a single dose given on the day of hatching or two doses given on days 1 and 14 of life). The number of Campylobacter was assessed in the intestinal contents of vaccinated birds.

Results: No statistically significant differences in colonisation levels were observed between chickens immunised with neutral liposomes containing hybrid proteins and their non-immunised counterparts, regardless of dosage regimen.

Conclusion: Although immunisation of chickens did not produce the expected results, the approach used has great potential, which is worth further investigation and development.

Introduction: The enteric nervous system (ENS) in the wall of the gastrointestinal tract is complex and comprises many neurons, which are differentiated in terms of structure, function and neurochemistry. Neuregulin 1 (NRG 1) is one of the neuronal factors synthesised in the ENS about the distribution and functions of which relatively little is known. The present study is the first description of the distribution of NRG 1 in the ENS in various segments of the porcine small intestine.

Material and methods: Fragments were excised from the duodenum, jejunum and ileum of five euthanised Piétrain × Duroc sows, 18-20 kg in weight and eight weeks of age. Paraformaldehyde-fixed and dehydrated tissue was sectioned and double-labelling immunofluorescence was performed using Alexa Fluor-conjugated secondary antibodies to visualise neuregulin 1 and its colocalisation with vasoactive intestinal polypeptide (VIP), galanin (GAL), and the neuronal isoform of nitric oxide synthase (nNOS) in the myenteric and inner and outer submucosal plexuses, with PGP 9.5 serving as a pan-neuronal marker.

Results: Neuregulin 1 was observed in all enteric plexuses in each segment of the small intestine. The percentage of NRG 1-positive neurons ranged from 8.38 ± 0.55% of all neurons in the jejunal inner submucous plexus to 21.52 ± 0.98% in the duodenal myenteric plexus. Cells which were NRG 1-positive also contained VIP, GAL and nNOS in all segments of the small intestine to a degree which varied by small intestine segment and enteric plexus type.

Conclusion: The results indicate that NRG 1-positive neurons are present in the ENS of the porcine small intestine and differ significantly neurochemically, which may suggest a multifaceted role for NRG-1 in the controlling of the small intestine activity.

Introduction: Crayfish plague is considered the most important crayfish disease globally. It is caused by the fungus-like agent, Aphanomyces astaci. This study aimed to identify and determine the prevalence of A. astaci using PCR in narrow-clawed crayfish (Pontastacus leptodactylus) populations from across Türkiye.

Material and methods: A PCR was carried out with primers specific to the internal transcribed spacer region of the A. astaci pathogen on both telson and abdominal cuticle tissues from crayfish individuals from 41 different locations.

Results: Aphanomyces astaci was detected in the crayfish from 34 of the locations. Molecular diagnosis showed the prevalence rates of A. astaci to be between 0% and 68.2%. For 7 of the 34 locations, the strain of A. astaci was determined. Microsatellite analysis of tissue from individuals with positive PCR results revealed the A. astaci genotypes in seven populations. Genotype B was found to be the predominant genotype responsible for crayfish plague in Turkish crayfish populations. The Psl genotype (genotype B) was determined in six of the populations, and the As genotype (genotype A) was detected in only one.

Conclusion: Crayfish plague poses a significant threat to crayfish populations, necessitating the development of rapid, highly sensitive diagnostic methods. An understanding of the sensitivity of the PCR detection method and of the prevalence and genotyping of A. astaci in Turkish crayfish populations has been gained from this study.

Introduction: The aim of this study was to estimate the occurrence of Echinococcus spp. and other helminth infections in grey wolves in south-eastern Poland.

Material and methods: Overall, 74 samples of wolf faeces were examined with a multiplex PCR and a system of real-time quantitative PCR methods to detect and identify Echinococcus spp. The faeces were additionally examined microscopically. Also, 20 samples of wolf intestines were examined with a sedimentation and counting technique (SCT).

Results: Echinococcus multilocularis DNA was detected in 6.8% and E. granulosus s.l. (identified as E. ortleppi) in 4.1% of faeces samples. Taenia spp. DNA was found in 43.2% and Mesocestoides in 4.1%. Examination of the intestines by SCT showed E. multilocularis worms in 10%, E. granulosus s.l. (E. ortleppi) in10%, Taenia spp. in 100%, hookworms in 30%, Alaria alata in 20%, Mesocestoides sp. in 10%, Trichuris vulpis in 15%, Molineus sp. in 5% and Euryhelmis sp. in 5%. By coproscopy, Capillariidae eggs were found in 59% of faeces samples. Genetic analysis of E. multilocularis worms showed the presence of two European haplotypes previously described in Poland in red foxes and pigs. Sequences of nad1 obtained from E. ortleppi worms shared full identity with a sequence from a human case in Poland.

Conclusion: The study showed the presence of E. multilocularis in wolves for the first time in Poland and confirmed our earlier observations on E. ortleppi. This double threat from Echinococcus in this wolf population should be taken into account when assessing the epidemiological risk. The study enriched the knowledge of other helminths found in wolves, also those (Euryhelmis) that were recorded for the first time in this species.

Introduction: The aim of the study was to compare selected leukocyte subpopulations and the serum amyloid A (SAA) concentration in the peripheral blood of cows at different stages of lactation. The blood of cows receiving a probiotic as a dietary supplement was compared with the blood of cows not receiving it.

Material and methods: The research was conducted on 20 pregnant dairy cows randomly divided into two groups of 10 cows each. The experimental group consisted of cows given the probiotic as a feed supplement. The control group consisted of cows that were fed without supplementation. Blood was drawn six times for testing: 7 days before drying; 14 days before parturition; and 7, 21, 60 and 90 days postpartum. Leukocyte immunophenotyping was performed by flow cytometry.

Results: The blood of cows administered the probiotic revealed an increased percentage of forkhead box protein 3 (Foxp3)⁺, T CD4⁺ and B CD25⁺ lymphocytes and β2 CD18⁺ and αM CD11b⁺ integrins, and persistently low SAA levels at all time points.

Conclusion: The activity of the immune system in cows receiving the probiotic was higher than in control cows. However, the stabilisation of the immune system of the supplemented cows may be indicated by the persistence of a low level of SAA throughout the experiment. Therefore, it can be assumed that the immune system of cows treated with the probiotic more easily adapts to changes in conditions in particular lactation periods and that these cows become more resistant to infectious diseases.

Introduction: This study explored the effects of prenatal exposure to fumonisins B (FB) on bone innervation in newborn Wistar rats.

Material and methods: Pregnant dams (n = 6 per group) were assigned to either the control or one of two FB-exposed groups (60 mg or 90 mg/kg body weight) from the 7^th day of gestation until parturition. On the day of parturition, one male pup from each litter (n = 6 per group) was randomly selected and euthanised, and their femurs were dissected for analysis. Bone innervation was quantified by examining the morphology patterns of sympathetic, parasympathetic, sensory and cocaine- and amphetamine-regulated transcript (CART)-positive fibres. Prepared bone sections were analysed using immunohistochemistry staining for protein gene product 9.5, tyrosine hydroxylase, choline acetyltransferase, vasoactive intestinal peptide (VIP), substance P and CART-positive neurons.

Results: The group that received a higher dose of FB demonstrated an increase in both the size and complexity of the complete bone neuronal network together with heightened sympathetic and sensory innervation, and displayed a decrease in neuron density and sympathetic innervation. Fumonisin B exposure led to a decrease in galanin-positive and VIP-positive bone neuronal networks in both groups exposed to FB, while in the lower-dose group, there was also a decrease in CART-positive innervation.

Conclusion: Prenatal FB exposure significantly influences the neuronal bone network of rats, which is essential for maintaining bone homeostasis. These findings emphasise the necessity for further research to understand the lasting effects and underlying mechanisms of alterations induced by FB.

Introduction: Escherichia coli is the most common uropathogen in humans, dogs and cats. Dietary consumption of cranberry (Vaccinium macrocarpon) is known to be associated with a reduction in uropathogenic E. coli (UPEC) adhesion to human and canine urinary epithelial cell lines, but this has not been shown in cats.

Material and methods: Six neutered domestic cats, one male and five females, were randomly fed three diets successively, one containing 0.1% cranberry powder, one containing 0.3% cranberry powder, and one being the control without cranberry. Naturally emitted urine was collected on the last two days of each period of two weeks and used for bacterial growth. Adherence to Crandell-Rees feline kidney (CRFK) uroepithelial cells of the feline UPEC C571 strain (positive for the papC gene marker for P-fimbriae and the fimA marker for type 1 pili and negative for the gene of the alpha haemolysin cytotoxin hlyA, and additionally non-haemolytic in vitro on blood agar) was quantified after growth in urine samples.

Results: Significant reductions in bacterial adherence to CRFK cells were observed for 60% of cats receiving 0.1% cranberry powder supplementation and for all cats receiving 0.3% cranberry powder supplementation, compared to the same animals consuming the control diet.

Conclusion: Dietary supplementation with cranberry may provide some degree of protection to cats against adhesion of UPEC to feline uroepithelial cells.

Introduction: Ticks are obligate blood-feeding arthropods that cause significant economic losses in domestic animal husbandry and threaten public health. However, information about soft ticks (Acari: Argasidae) and tick-borne pathogens in the Xinjiang Uygur Autonomous Region (XUAR) of China is scarce.

Material and methods: In this study, PCR assays and gene sequencing were used to detect and analyse the epidemiological features of Anaplasma ovis, Theileria ovis and Brucella abortus parasitic infections in 366 Ornithodoros lahorensis soft ticks collected from five sampling sites in the XUAR from October 2019 to March 2022. The ticks were identified by morphological and molecular methods as O. lahorensis. The PCR was conducted using primers complementary to the major surface protein 4 (Msp4) gene of A. ovis, the 18S ribosomal RNA (18S rRNA) of T. ovis and the outer membrane protein 22 (Omp22) gene of B. abortus.

Results: The overall infection rate was 91/366 (24.9%) for A. ovis, 127/366 (34.7%) for T. ovis and 94/366 (25.6%) for B. abortus. Sequencing analysis indicated that A. ovis Msp4, T. ovis 18S rRNA and B. abortus Omp22 genes from XUAR isolates showed 99.58-100% identity with documented isolates from other countries.

Conclusion: This study provides fundamental evidence for the occurrence of A. ovis, T. ovis and B. abortus in O. lahorensis. Therefore, the potential threat of soft ticks to livestock and humans should not be ignored. This study expands the understanding of the existence of tick-borne pathogens in O. lahorensis and is expected to improve the strategies for prevention and control of ticks and tick-borne diseases in China.

Introduction: Apart from their antioxidant activity, plant-derived bioactive compounds can also positively affect the quality of meat and meat products by improving their sensory and microbiological properties and preventing discolouration. The aim of this study was to determine how the addition of different forms of rosemary improved the quality of pork.

Material and methods: Minced pork samples were divided into a control sample without additives (C) and three experimental samples with certified additives (15 mg/kg of meat each), i.e. rosemary oleoresin (ROL), extract (REX) and essential oil (REO). Each was further divided into three subsamples; the first was evaluated before storage, and the second and third were evaluated after respective 7- and 14-day vacuum-packed storage at 2°C. The TBARS value was expressed as mg of malondialdehyde (MDA) per kg of meat. Colour was determined based on the values of the standard colour space values of L* (lightness), a* (redness) and b* (yellowness) as well as C* (chroma) and h° (hue angle). Sensory attributes of the samples were evaluated on a nine-point scale. The pour-plating procedure was used for the enumeration of Pseudomonas, mesophilic lactic acid bacteria, psychrotrophic bacteria and rods of the Enterobacteriaceae family. Within each bacterial group, the most common colonies were identified by matrix-assisted laser desorption and ionization (MALDI).

Results: Lipid oxidation was most effectively inhibited by REO. The addition of ROL and REO to pork lightened its colour. Meat with REO had stronger redness, whereas meat with ROL had stronger yellowness. The addition of REX affected the sensory properties of pork most beneficially. Neither Enterobacteriaceae nor Pseudomonas spp. were detected in REO pork, which also contained lower counts of lactic acid bacteria than group C pork.

Conclusion: The results of this study indicate that rosemary has antioxidant and antimicrobial properties, and may improve the colour and sensory attributes of pork. The effect exerted by rosemary on meat quality may vary depending on the physical form of the additive.

Introduction: Chokeberry pomace, rich in polyphenolic compounds, holds potential to be a valuable feed additive for enhancing the antioxidative capacity and overall quality of milk. This study explores the impact of dietary inclusion of chokeberry pomace on oxidative stress parameters and other milk quality parameters in high-producing dairy goats.

Material and methods: Twenty-seven goats were allocated into three groups: a control group provided standard feed and two experimental groups provided feed supplemented with 15 g or 30 g of chokeberry pomace per kilogram. Milk samples were analysed for physicochemical traits, a range of enzyme activities and antioxidant properties.

Results: Supplementation with chokeberry pomace significantly reduced milk fat content, enhanced antioxidative properties and increased most of the quantified enzyme activities. Total polyphenol content and reduced glutathione levels were significantly higher in the supplemented groups, correlating with improved antioxidative potential of the milk.

Conclusion: Chokeberry pomace in goat diets enhances milk's antioxidative properties and upregulates its enzymatic activity profile, suggesting a potential strategy to improve the nutritional quality and health benefits of goat milk. The study underscores the utility of chokeberry pomace as a feed additive that might not only benefit animal health but also contribute to enhanced milk quality.