Imunoprofilaksa kunića protiv krpelja Rhipicephalus haemaphysaloides uporabom pročišćenoga antigena srednjega crijeva od 35 kDa.

A 35 kDa midgut polypeptide of Rhipicephalus haemaphysaloides was isolated for the first time by immunoaffinity chromatography using immunoglobulin ligands from rabbits immunized with 35 kDa midgut polypeptide. An experimental immunization study was conducted on 12 New Zealand white rabbits using affinity purified 35 kDa midgut antigen (Aff - RhGM 35 kDa Ag) with Freund’s adjuvant. The humoral immune response was evaluated by ELISA. After tick challenge, reduction in the number, mass and oviposition capacity of engorged females was observed in the tick population that had fed on immunized animals. The results indicated a high efficacy of 83.3%, demonstrating the efficiency of the immune response elicited by 35 kDa midgut antigen to control the tick Rhipicephalus haemaphysaloides.Polipeptid od 35 kDa podrijetlom iz srednjega crijeva krpelja Rhipicephalus haemaphysaloides prvi put je izdvojen postupkom imunoafinitetne kromatografije rabeći imunoglobulinske ligande dobivene imunizacijom kunića. Ukupno 12 bijelih novozelandskih kunića bilo je pokusno imunizirano ubrizgavanjem pročišćenoga antigena pomiješanog s Freundovim adjuvansom. Humoralni odgovor bio je određen imunoenzimnim testom. Nakon izazivačke infestacije imuniziranih kunića uočene su značajne razlike u odnosu na kontrolnu skupinu. U imuniziranih kunića ustanovljen je manji broj krpelja, njihova manja težina te smanjena plodnost nasisanih ženki. Rezultati su pokazali učinkovitost od 83,3% što pokazuje da je imunosni odgovor na antigen srednjega crijeva od 35 kDa potaknuo dovoljan imunosni odgovor za kontrolu infestacije krpeljom Rhipicephalus haemaphysaloides

Razvitak imunoenzimnog testa s jedostrukim razrjeđenjem seruma za dokaz protutijela za virus zarazne bolesti burze

Determination of antibody titres of sera collected from poultry flock to diagnose IBDV infected chickens by developing single serum working dilution ELISA (SSD-ELISA) was made. The indirect ELISA standard procedure was adopted with standard positive and negative serum controls. The standard IBDV antigen was prepared using the Tamil Nadu isolate of IBDV. The relative sensitivity and specificity of a single serum dilution ELISA test in qualitative comparison with the commercial kit were 82% and 100% respectively and the accuracy was 82.1%. This single serum dilution assay gave reproducible results and allowed considerable savings on the time and cost of reagents compared with indirect ELISA. Based on these results a SDS-ELISA kits have been developed in this study to replace the commercial kit. The IBDV antigen coated ELISA plates can be stored under refrigeration and the test can be performed rapidly under field conditions by trained personnel.Titar protutijela za virus zarazne bolesti burze određen je u uzorcima seruma pilića razvijenim imunoenzimnim testom s jednostrukim razrjeđenjem uzoraka seruma. Standardni imunoenzimni test prilagođen je uz uporabu standardnih pozitivnih i negativnih kontrolnih uzoraka seruma. Standardni antigen za virus zarazne bolesti burze bio je pripravljen od izolata Tamil Nadu virusa. U usporedbi s komercijalnim kompletom, osjetljivost testa iznosila je 82%, a specifičnost 100%. Točnost mu je bila 82,1%. Razvijenim testom postignuti su reproducibilni rezultati uz znatnu uštedu vremena i materijala pa se može uporabiti umjesto komercijalnih kompleta. Antigen se može pohraniti u hladnjaku, a uvježbano osoblje može brzo izvesti test u terenskim uvjetima

Defined Antigen Skin Test for Bovine Tuberculosis Retains Specificity on Revaccination With Bacillus Calmette–Guérin

The Bacillus Calmette–Guérin (BCG) vaccination provides partial protection against, and reduces severity of pathological lesions associated with bovine tuberculosis (bTB) in cattle. Accumulating evidence also suggests that revaccination with BCG may be needed to enhance the duration of immune protection. Since BCG vaccine cross-reacts with traditional tuberculin-based diagnostic tests, a peptide-based defined antigen skin test (DST) comprising of ESAT-6, CFP-10, and Rv3615c to detect the infected among the BCG-vaccinated animals (DIVA) was recently described. The DST reliably identifies bTB-infected animals in experimental challenge models and in natural infection settings, and differentiated these from animals immunized with a single dose of BCG in both skin tests and interferon-gamma release assay (IGRA). The current investigation sought to assess the diagnostic specificity of DST in calves (Bos taurus ssp. taurus × B. t. ssp. indicus; n = 15) revaccinated with BCG 6 months after primary immunization. The results show that none of the 15 BCG-revaccinated calves exhibited a delayed hypersensitivity response when skin tested with DST 61 days post-revaccination, suggesting 100% diagnostic specificity (one-tailed lower 95% CI: 82). In contrast, 8 of 15 (diagnostic specificity = 47%; 95% CI: 21, 73) BCG-revaccinated calves were positive per the single cervical tuberculin (SCT) test using bovine tuberculin. Together, these results show that the DST retains its specificity even after revaccination with BCG and confirms the potential for implementation of BCG-based interventions in settings where test-and-slaughter are not economically or culturally feasible

A Defined Antigen Skin Test That Enables Implementation of BCG Vaccination for Control of Bovine Tuberculosis:Proof of Concept

In most low- and middle-income countries (LMICs), bovine tuberculosis (bTB) remains endemic due to the absence of control programs. This is because successful bTB control and eradication programs have relied on test-and-slaughter strategies that are socioeconomically unfeasible in LMICs. While Bacillus Calmette–Guérin (BCG) vaccine-induced protection for cattle has long been documented in experimental and field trials, its use in control programs has been precluded by the inability to differentiate BCG-vaccinated from naturally infected animals using the OIE-prescribed purified protein derivative (PPD)-based tuberculin skin tests. In the current study, the diagnostic specificity and capability for differentiating infected from vaccinated animals (DIVA) of a novel defined antigen skin test (DST) in BCG-vaccinated (Bos taurus ssp. taurus x B. t. ssp. indicus) calves were compared with the performance of traditional PPD-tuberculin in both the skin test and in vitro interferon-gamma release assay (IGRA). The IFN-γ production from whole blood cells stimulated with both PPDs increased significantly from the 0 week baseline levels, while DST induced no measurable IFN-γ production in BCG-vaccinated calves. None of the 15 BCG-vaccinated calves were reactive with the DST skin test (100% specificity; one-tailed lower 95% CI: 82). In contrast, 10 of 15 BCG-vaccinated calves were classified as reactors with the PPD-based single intradermal test (SIT) (specificity in vaccinated animals = 33%; 95% CI: 12, 62). Taken together, the results provide strong evidence that the DST is highly specific and enables DIVA capability in both skin and IGRA assay format, thereby enabling the implementation of BCG vaccine-based bTB control, particularly in settings where test and slaughter remain unfeasible

Corrigendum: A Meta-Analysis of the Effect of Bacillus Calmette-Guérin Vaccination Against Bovine Tuberculosis:Is Perfect the Enemy of Good?

More than 50 million cattle are likely exposed to bovine tuberculosis (bTB) worldwide, highlighting an urgent need for bTB control strategies in low- and middle-income countries (LMICs) and other regions where the disease remains endemic and test-and-slaughter approaches are unfeasible. While Bacillus Calmette-Guérin (BCG) was first developed as a vaccine for use in cattle even before its widespread use in humans, its efficacy against bTB remains poorly understood. To address this important knowledge gap, we conducted a systematic review and meta-analysis to determine the direct efficacy of BCG against bTB challenge in cattle, and performed scenario analyses with transmission dynamic models incorporating direct and indirect vaccinal effects (“herd-immunity”) to assess potential impact on herd level disease control. The analysis shows a relative risk of infection of 0.75 (95% CI: 0.68, 0.82) in 1,902 vaccinates as compared with 1,667 controls, corresponding to a direct vaccine efficacy of 25% (95% CI: 18, 32). Importantly, scenario analyses considering both direct and indirect effects suggest that disease prevalence could be driven down close to Officially TB-Free (OTF) status (<0.1%), if BCG were introduced in the next 10-year time period in low to moderate (<15%) prevalence settings, and that 50–95% of cumulative cases may be averted over the next 50 years even in high (20–40%) disease burden settings with immediate implementation of BCG vaccination. Taken together, the analyses suggest that BCG vaccination may help accelerate control of bTB in endemic settings, particularly with early implementation in the face of dairy intensification in regions that currently lack effective bTB control programs

Spectrum of vaginal lactic acid bacteria in indigenous and cross bred cows of India

Lactic acid bacteria (LAB) are beneficial microorganisms present in the bovine vagina. Documentation of LAB community in the vagina of indigenous and cross bred dairy cows of India is important to further establish its probiotic potential. The aim of this study was to isolate and identify the spectrum of LAB by phenotypic and genotypic methods. A total of 24 LAB were isolated from the vagina of 110 apparently healthy indigenous and cross bred cows. The LAB isolates belonged to the genus Lactobacillus, Bacillus, Enterococcus and Weisella and were further speciated based on their grouping with respective reference sequences available in the GenBank, on phylogenetic analysis. The species diversity of bovine vaginal LAB identified in this study was Lactobacillus agilis (17%), Lactobacillus mucosae (8%), Lactobacillus plantarum (21%), Lactobacillus fermentum (17%), Lactobacillus pentosus (4%), Weisella cibaria (8%), Bacillus coagulans (4%), Bacillus cereus (4%), Enterococcus faecium (13%) and Enterococcus asini (4%). The overall spectrum and relative abundance of the bovine vaginal LAB reported in this study provides critical information for the formulation of uterine probiotics for the prevention/treatment of bovine clinical endometritis.