Humoral and Cellular Response of Pheasants Vaccinated against Newcastle Disease and Haemorrhagic Enteritis

The purpose of the experiment was to define whether and to what extent can prophylactic vaccinations against Newcastle disease (ND) and haemorrhagic enteritis (HE) affect the humoral and cellular response in pheasants. The evaluation of humoral response was performed on a basis of agglutinin titre after administered antigen and the cellular immunity index was the delayed type hypersensitivity (DTH) reaction. The pheasants were prophylactically vaccinated against Newcastle Disease (ND) on the 1st, 28th and 56th day of life. Moreover, on the 49th day of life, part of the birds was given in the drinking water a vaccine containing the HEV (Haemorrhagic Enteritis Virus). Fourteen days after the HEV vaccination, the birds were intravenously given 0.5 ml of the 10% SRBC (sheep red blood cells) suspension. Simultaneously with the SRBC administration the delayed hypersensitivity test was performed by intradermal administration of phytohaemagglutinin (PHA). It was shown that in pheasants vaccinated with NDV and additionally with HEV, the specific agglutinin anti-SRBC titre was significantly (p < 0.05) lower than in birds vaccinated against ND only. It also appeared that, the antibodies resistant to 2-mercaptoethanol were 43% of the total pool of specific anti-SRBC antibodies in the NDV vaccinated birds, whereas in birds vaccinated also with HEV they were 75%. No significant differences were found in the DTH test. Only in the HEV vaccinated pheasants the tendency to increase the wing index value was noted. The results confirm the observations concerning immunosuppressive effects of simultaneous vaccinations. They also indicate that overloading the pheasants with many antigens (ND and HEV vaccination) may weaken the humoral response to administered SRBC

Effect of ochratoxin A on the intestinal mucosa and mucosa-associated lymphoid tissues in broiler chickens

The immunotoxic effect of ochratoxin A (OTA) on the intestinal mucosa-associated lymphoid tissue and its cytotoxic action on the intestinal epithelium were studied in broiler chickens experimentally treated with the toxin. From the 7th day of life, 80 male broiler chickens (Ross 308) were randomly divided into four groups of 20 birds each. The three experimental groups (E1-3) were treated with OTA for 28 days (E1: 50 μg/kg body weight [bw]/day; E2: 20 μg/kg bw/day; E3: 1 μg/kg bw/day) and the fourth group served as control. Histological examination of the intestinal mucosa and immunohistochemical staining for identification of CD4+, CD8+, TCR1 and TCR2 lymphocytes in the duodenum, jejunum and ileocaecal junction were performed, and CD4+/CD8+ and TCR1/TCR2 ratios were calculated. OTA toxicity resulted in decreased body weight gain, poorer feed conversion ratio, lower leukocyte and lymphocyte count, and altered intestinal mucosa architecture. After 14 days of exposure to OTA, immunohistochemistry showed a significant reduction of the lymphocyte population in the intestinal epithelium and the lamina propria. After 28 days of exposure, an increase in the CD4+ and CD8+ values in both the duodenum and jejunum of chickens in Groups E1 and E2 was observed, but the TCR1 and TCR2 lymphocyte counts showed a significant reduction. No significant changes were observed in Group E3. The results indicate that OTA induced a decrease in leukocyte and lymphocyte counts and was cytotoxic to the intestinal epithelium and the mucosa-associated lymphoid tissue, altering the intestinal barrier and increasing susceptibility to various associated diseases

Dermacentor reticulatus (Fabricius, 1794) and Babesia canis (Piana et Galli-Valerio, 1895) as the parasites of companion animals (dogs and cats) in the Wroclaw area, south-western Poland

Tests performed in 2013 and 2014 revealed the occurrence of three tick species parasitizing pet cats and dogs in the Wrocław Agglomeration. In total, 1,455 tick specimens were removed from 931 hosts (760 dogs and 171 cats) in 18 veterinary clinics. The dominant tick species was Ixodes ricinus (n=1272; 87.4%), followed by I. hexagonus (n=137; 9.4%) and Dermacentor reticulatus (n=46; 3.2%). Females were the most often collected development stage among I. ricinus and D. reticulatus, and nymphs among I. hexagonus. Additionally, D. reticulatus ticks (n=337) were then collected from vegetation in the Wrocław area to detect Babesia canis; however, none was found positive. Only 9.0% of dog blood samples sent to VETLAB were positive for Babesia spp. Negative results for B. canis from ticks may result from the short period of the occurrence of D. reticulatus in the Wrocław area and therefore the vectorpathogen cycle may not have been fully established at the time of the study. Nevertheless, D. reticulatus is expanding its range, and the size of its population in the Wrocław Agglomeration is increasing. The presence of the pathogenic Babesia spp. combined with the occurrence of its main vector¸ D. reticulatus, suggests that the epizootiological situation in the area can change and may pose a new veterinary problem in the future