Polish journal of veterinary sciences最新文献

The objective of this study was to investigate the effect of mannose oligosaccharides (MOS) against cadmium (Cd)-induced hepatic oxidative damage and analyze its underlying antioxidant mechanism. Thirty male Sprague-Dawley (SD) rats were randomly divided into five groups: control group and four others treated with cadmium chloride (CdCl2) (2 mg/kg body weight (b.w.)) and different MOS levels at 0, 100, 300, 500 mg/kg b.w.. The results demonstrated that administration of MOS at a dose of 500 mg/kg significantly reduced Cd-induced oxidative damage in rat livers. This was evidenced by an increase in body weight gain (BWG) and thymus index. Additionally, liver superoxide dismutase (SOD), catalase (CAT) and total antioxidant capacity (T-AOC) activities were significantly improved compared to the group exposed to Cd alone. Conversely, MOS resulted in significant reductions in the liver index, liver malondialdehyde (MDA), hydrogen peroxide (H2O2), glutathione (GSH), and serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels. Morphological analysis showed that MOS ameliorated Cd-induced histopathology of the rat liver. Notably, Nrf2 gene expression levels increased, while heme oxygenase 1 (HO-1) and quinone oxidoreductase 1 (NQO1) mRNA levels decreased in the MOS group. In conclusion, MOS effectively attenuate Cd-induced oxidative damage in rat liver and the Nrf2 signaling pathway is involved in this process. This study provides valuable insights for the implementation of MOS applications in livestock and poultry production.

The global consumption of poultry is expected to increase by 2032, especially in Asian and European countries. Proper nutrition, including feed additives, plays a role in meeting the global demand for livestock products. In addition, the use of antibiotics as growth promoters resulted in antibiotic resistance issues, leading to the need to investigate alternative methods for replacing the role of antibiotics. The use of probiotic bacteria has proved to improve the growth performance of poultry and suppress pathogenic bacteria growth in the digestive tract. However, microenvironment conditions in the digestive tract affect the survival of probiotic bacteria. Modification of bacteria by encapsulation shows promising potential to protect bacteria from the harsh conditions in the poultry digestive tract. In addition, probiotic encapsulation also showed improvement in performance in poultry. This review will discuss the current encapsulation technology in probiotics applied to poultry and its effects. It also will explore the prospect of encapsulated probiotics, especially in the poultry industry, and its challenge.

Study objective: This study aimed to evaluate the impact of body condition score (BCS) on the milk yield, reproductive performance, and health status of lactating dairy cows.

Methods: Data were collected from 1,960 cows across four dairy farms at 21 days prepartum, on the day of calving, and at 21, 50, 150, 200, and 250 days postpartum.

Results: The results demonstrated significant differences in BCS, milk yield, reproductive performance, and disease incidence among cows from different dairy farms.

Conclusion: These findings suggest that the ideal BCS for cows at 21 days prepartum and on the day of calving is 3.5, while BCS of 3.25 is optimal for cows at 21 days postpartum, and BCS of 3.0 is recommended for cows from 50 to 250 days postpartum.

This study is a continuation of innovative research on the impact of the simultaneous use of standard- and small-cell combs in bee colonies on the characteristics of worker bees and bee colonies. The nests of these colonies had two types of combs: small-cell (approximate cell width/size of 4.90 mm) and standard-cell (approximate cell width/size of 5.50 mm). The aim of the study was to compare the activities of proteases and their inhibitors present on the cuticle of workers reared in small-cell combs (SMC workers) and standard-cell combs (STC workers) in colonies kept simultaneously in standard- and small-cell combs. The width/size of comb cells in which the workers were reared had a significant effect on protein concentrations and activities of the proteolytic system, i.e. proteases and their inhibitors, on the cuticle surface. Regardless of the age of the workers (1 day, 7 days, 14 days, 21 days, and 28 days), the protein concentrations were statistically significantly higher (p≤0.01) in the STC than SMC workers. The opposite was found in the case of the activities of proteases and their inhibitors: regardless of the age of the bees, the activities were significantly higher in the SMC workers. The differences between workers reared in small-cell combs and those reared in standard-cell combs may be responsible for their predispositions to perform different tasks in the colony. In our opinion, workers reared in small-cell combs are more predisposed to work as foragers outside the nest. However, this hypothesis requires confirmation in further research.

The purpose of this study was to compare the effect of the age of the breeder flock of commercial BUT - 6 turkeys on the transfer of maternal antibodies to chicks. The blood samples for serological analysis were collected from randomly selected 63 female breeders from a flock of BUT Big 6 turkeys and 63 one-day-old hybrid turkey poults hatched from eggs from this flock at 36, 45 and 54 week of age. During blood analysis (serum) in the laboratory, the level of antibodies of the breeder flock against Avian metapneumoviruses (APV), Newcastle disease virus (NDV) and Hemorrhagic enteritis virus (HEV) was determined (ELISA). Maternal antibody (MatAb) titer in chicks (serum) against the same viruses were also determined. The percentage (%) transfer of MatAb to offspring was then evaluated. The effect of the age of the turkeys on the antibody titer to the tested pathogens expressed in geometric mean titers (GMT) was shown. During the laying period, the antibody titer of the tested turkeys against NDV decreased with the age of the flock. The highest antibody titer was demonstrated in week 36 (GMT=14242), whereas the lowest was in week 54 (GMT=5564). In contrast, the serum antibody titer of the tested layers against APV and HEV increased with the age of the birds. The lowest antibody titer (GMTAPV=24818; GMTHEV=12070) was observed at the beginning of the laying period, and the highest at the end of the laying period (GMTAPV =38978; GMTHEV =13980). The highest vertical transfer to offspring was shown for antibodies to - HEV (82.7%), while the lowest was shown when analyzing sera to - NDV (37.6%). The present analysis showed significant differences in the evaluated antibody titres in serum of turkey breeders during the laying period, as well as in the level of MatAb in chicks. The results also indicate that the transfer of MatAb to chicks is influenced by the age of the parent flock and the type of pathogen against which the layers were vaccinated.

Honey is natural nectar that honey bees gather from a variety of flowers. Honey is made up of many nutrients that are essential for the growth and development of various tissues and organs in all kinds of living organisms. The goal of the current study was to determine whether adding honey to diets of naked neck cocks would have a good impact on their semen quality, haematological profile, and immune system. A total of 90 naked neck cocks that were 75 weeks old were gathered for this purpose in March and April 2021 from the University of Agriculture Birds Stock. The birds were divided into 3 equal treatment groups: control, A and B, which each received a dose of 5 and 10 g of honey in 1 litre of water (w/v), respectively. The control group received no treatment. Five weeks of treatment were given, with one week serving as an adaptation period. One-way analysis of variance was applied to the recorded data for statistical analysis. The addition of honey to drinking water at a dose of 10 g (w/v) increased (p<0.05) sperm motility, followed by a dose of 5 g (w/v) and the control group, but the mean values of non-motile sperms were lowest (p<0.05) at a dose of 10 g (w/v), followed by a dose of 5 g (w/v), and the control group. However, there were no significant differences in semen volume, pH, or concentration across the treatment groups. The haematological parameters, such as haemoglobin, total leukocyte count, red blood cells, and packed cell volume, were not significantly affected by the addition of honey to the drinking water, but the ND titer of naked neck cocks treated with 10 g (w/v) honey was significantly (p<0.05) higher than that of the cocks in the 5 g (w/v) and control group. In conclusion, the addition of honey to drinking water at a dose of 10 g (w/v) may have positive effects on sperm motility and antibody titer against Newcastle disease in aged naked neck cocks. Furthermore, these results also suggest that the addition of honey to drinking water at a dose of 10 g (w/v) may rejuvenate naked neck cocks even at old age (75 week age).

An animal body's immune response to viruses might vary depending on various factors. The relationship between 2'-5'-oligoadenylate synthetase like (OASL), interferon alpha (IFN-α), and duck hepatitis A virus type 3 (DHAV-3) virus genome copy number in duck embryo tissues was studied to investigate duck's natural antiviral immunity mechanism. 15-day-old SPF duck embryos were infected with DHAV-3 and their organs and tissues were collected at various times after inoculation. RT real-time PCR was used to determine OASL and IFNA mRNA expression levels and the DHAV-3 copy number. Compared with that at 0 hours, liver OASL transcription increased significantly at 24 hours, and extremely significantly in the liver, heart, gizzard, small intestine, and muscle at 48 hours. The heart had the highest expression level, followed by the liver, with lower expression in the other tissues. There was no significant difference in IFNA expression between the heart and liver at 12 hours, but it started to rise at 24 hours, reaching its maximum at 48 hours. Although IFNA expression increased in the gizzards, small intestines, and muscles, its relative expression levels were lower than those in the heart and liver. In the tissues, the virus genome copy number peaked at 24 hours, and then decreased. The liver had the highest virus genome copy number, followed by the heart. The results implied that the differences in OASL transcription in the tested tissues were similar to those of IFNA. Thus, the immune response (OASL and IFN-α levels) of duck embryos to DHAV-3 shows tissue differences, especially in the liver and heart.

The control of respiratory infections is integral to a healthy livestock farm. The current study was conducted to optimize a multiplex PCR assay for simultaneous detection of Pasteurella multocida (P. multocida), Staphylococcus aureus (S. aureus) and Mycobacterium bovis (M. bovis) in nasal samples of cattle having suspicion of respiratory tract infections. The nasal samples were collected from 10 dairy farms affected with respiratory disease outbreaks in the recent past. These outbreaks were associated with respiratory tract infections caused by bacterial pathogens P. multocida, S. aureus and M. bovis. A multiplex PCR assay was therefore optimized to enable the simultaneous detection of these bacterial pathogens directly from nasal samples. The multiplex PCR assay was optimized using primers already validated for efficient amplification of specific DNA segments in reference strains of targeted bacterial pathogens. The standardized assay was specific and sensitive enough to detect ≥100 genome equivalents of target DNA segments in each of P. multocida, S. aureus and M. bovis. The assay was successfully applied for the detection of the three bacterial pathogens in 50 nasal samples. PCR amplicons were subjected to Sanger dideoxy sequencing followed by phylogenetic analysis to determine if species identification was specific. In short, the optimized multiplex PCR assay may prove as a reliable, economical, and simple tool for the management of bovine respiratory tract infections caused by some key bacterial pathogens.

Postpartum inactive ovaries (IO) in dairy cows reduce the economic returns of the dairy industry. It is related to energy metabolism disorder, hormone levels and cytokines. The aim of this study was to evaluate the correlation between insulin resistance (IR), adiponectin (ADPN), and leptin (LEP) at 14 days postpartum to assess the predictive potential for IO risk in dairy cows. Cows at 14 days postpartum were randomly selected and allocated into an insulin resistance group (IR, with IR index < 2.5, n=30) and a non-insulin resistance (non-IR, with IR index > 2.5, n=30). Serum Samples were collected at 14 and 55 days postpartum. Six cows of estrus and six cows of IO were randomly selected for slaughter at 55 days postpartum. Then, adipose and ovary samples were allocated for further experiments. A significant association between IR and IO, with 53.33% prevalence in the IR group compared to 16.67% in the non-IR group. Cows with IR had higher levels of β-hydroxybutyrate, non-esterified fatty acid, and lower levels of glucose, total cholesterol, triglyceride, ADPN, and LEP. Reproductive performance was adversely affected, with IR cows showing longer durations for first estrus and reduced milk yield. ADPN and LEP levels were significantly lower in IR cows, suggesting their role in modulating insulin sensitivity and reproductive functions. The combined analysis of ADPN, LEP, and IR index showed high sensitivity (91.3%) and specificity (87.2%) in predicting IO, highlighting their potential as reliable biomarkers. These observations indicate that IR and serum LEP and ADPN at 14 days postpartum can predict IO in dairy cows.

Porcine reproductive and respiratory syndrome (PRRS) is caused by the PRRS virus (PRRSV). It leads to reproductive disorders and respiratory failure in sows and piglets. As an endoribonuclease, the PRRSV non-structural protein 11 (NSP11) is crucial in replication and assists immune system evasion. NSP11, which is relatively more conserved than NSP2, could potentially cause a new round of PRRSV epidemics, given a major mutation occurs. Here, we aimed to analyze the PRRSV-2 NSP11 genetic diversity in China between 1996-2022. The NSP11 nucleotide sequence was analyzed in 60 PRRSV-2 strains, revealing a similarity of 83.6% - 100%. Similarly, amino acid sequences exhibited homology ranges of 91.0% - 100.0%. Amino acid sequence alignment analysis revealed multiple substitutions in NSP11. NSP11 phylogenetic analysis of 489 PRRSV-2 strains revealed that Lineages 8 and 1 were the predominant strains of PRRSV circulating in China. These two lineages exhibit relatively close genetic relationships. Although unsupported by SimPlot analysis, recombination analysis suggested a potential recombination event in the 489 PRRSV-2 NSP11 sequences. Recombination analysis and amino acid sequence alignment confirmed the PRRSV NSP11 conservation. Our findings provide genetic diversity of PRRSV-2 NSP11 in China and contribute to effective strategy development to prevent and control PRRSV.