Is malaria the cause for decline in the wild population of the Indian White-backed vulture (Gyps bengalensis)?

The populations of three species of Gyps vultures have shown a decline of more than 95% between 1988 and 1999 in the Indian subcontinent and are now classified as 'critically endangered'. The indiscriminate and widespread veterinary use of diclofenac has been implicated for the decline of the White-backed vulture (Gyps bengalensis) in Pakistan, India and Nepal. Similar trends in population decline as seen in the northern regions have also been recorded in Central and South India, but the cause for the decline was not investigated. Here we report a study carried out in a densely forested and sparsely populated region in Central India. An intracellular malarial parasite was identified from the tissues of both live and dead Whitebacked vultures. Further, amplification and sequence analysis of the consensus sequence of the mitochondrial small and large sub-unit rRNA genes indicated a 95-96% similarity with the mitochondrial sequence of Plasmodium falciparum (DQ642845) and other Plasmodium species. In addition, amplification and sequencing of a 502 bp fragment of the mitochondrial cyt b gene identified the haemoprotozoan with Plasmodium sp. AP70, an avian malarial parasite. During the course of this study we also rescued two terminally ill vultures with symptoms of malaria, and treatment with anti-malarials led to their recovery. None of the affected vultures had diclofenac residues, thus implying that malaria could be an additional cause for the decline for the White-backed vulture population

Učinak višebiljnoga pripravka Toxiroak® dodanoga hrani u tijeku izazvane aflatoksikoze, ohratoksikoze i kombiniranih mikotoksikoza u tovnih pilića.

An experiment was conducted to study the protective role of polyherbal feed supplement (Toxiroak®) during induced mycotoxicosis in broilers. A total of 240 Vencobb one-day-old broilers were divided into eight equal groups. Group A served as control and was given plain feed. Groups B, D, F and H were given Toxiroak® at 0.75 g/kg of feed. Groups C, D, G and H were given dietary aflatoxin B1 at 0.2 ppm, and Groups E, F, G and H were given ochratoxin A at 0.2 ppm in feed to study the effect of Toxiroak® on individual aflatoxicosis, ochratoxicosis and combined mycotoxicosis of broilers. Chicks were given their respective feeds from the 1st day to 6th week of age and were vaccinated at 7th and 28th days of age with a Lasota strain of Newcastle disease virus. There was a significant effect of mycotoxins, individually and in combination, on body mass of broilers. Toxiroak® protected the effect of individual mycotoxins on body mass. Feed conversion ration was highest in Group B birds, followed by Groups A, F, D, H, C, E and G. Significant restoration of haemoglobin and total leukocyte count values in broilers due to feeding of Toxiroak® in co-mycotoxicated and aflatoxins-fed groups, respectively, was observed. There was no significant effect of mycotoxin treatment on packed cell volume and total erythrocyte count in broilers. Due to single and combined mycotoxicosis there was a reduction in serum total protein, cholesterol and triglyceride and a rise in creatinine and uric acid levels. Supplementation of diets with Toxiroak® reduced the changes induced due to mycotoxins. There was a significant increase in the percentage organ weight of liver, and a reduction in that of spleen, bursa of Fabricius and thymus of broilers fed mycotoxins. Protection of changes in the percentage of organ mass of these organs by supplementation of Toxiroak® was recorded only in respect of bursa of Fabricius. The observed impaired immune response and histopathological changes in liver, kidney, spleen, bursa of Fabricius and thymus of broilers given mycotoxins was protected by Toxiroak® supplementation.Izveden je pokus radi istraživanja zaštitne uloge višebiljnog dodatka hrani (Toxiroak®) u tijeku izazvane mikotoksikoze u tovnih pilića. Ustanovljena je znatno veća masa jetara te smanjena slezena, Fabricijeva burza i timus u pilića koji su dobivali mikotoksine. Zaštitna uloga pripravka Toxiroak®, s obzirom na masu organa, ustanovljena je samo za Fabricijevu burzu. Oslabljeni imunološki odgovor te patohistološke promjene u tkivu jetara, bubrega, Fabricijeve burze i timusa u pilića koji su dobivali mikotoksine bile su poboljšane dodatkom Toxiroak®

PCR-based detection of genes encoding virulence determinants in Staphylococcus aureus from bovine subclinical mastitis cases

The present study was carried out to genotypically characterize Staphylococcus aureus (S. aureus) isolated from bovine mastitis cases. A total of 37 strains of S. aureus were isolated during processing of 552 milk samples from 140 cows. The S. aureus strains were characterized phenotypically, and were further characterized genotypically by polymerase chain reaction using oligonucleotide primers that amplified genes encoding coagulase (coa), clumping factor (clfA), thermonuclease (nuc), enterotoxin A (entA), and the gene segments encoding the immunoglobulin G binding region and the X region of protein A gene spa. All of the isolates yielded an amplicon with a size of approximately 1,042 bp of the clfA gene. The amplification of the polymorphic spa gene segment encoding the immunoglobulin G binding region was observed in 34 isolates and X-region binding was detected in 26 isolates. Amplification of the coa gene yielded three different products in 20, 10, and 7 isolates. The amplification of the thermonuclease gene, nuc, was observed in 36 out of 37 isolates. All of the samples were negative for the entA gene. The phenotypic and genotypic findings of the present strategies might provide an understanding of the distribution of the prevalent S. aureus clones among bovine mastitis isolates, and might aid in the development of steps to control S. aureus infections in dairy herds

Investigation of Immune Biomarkers Using Subcutaneous Model of M. tuberculosis Infection in BALB/c Mice: A Preliminary Report

Evaluation and screening of vaccines against tuberculosis depends on development of proper cost effective disease models along with identification of different immune markers that can be used as surrogate endpoints of protection in preclinical and clinical studies. The objective of the present study was therefore evaluation of subcutaneous model of M.tuberculosis infection along with investigation of different immune biomarkers of tuberculosis infection in BALB/c mice. Groups of mice were infected subcutaneously with two different doses : high (2×106 CFU) and low doses (2×102 CFU) of M.tuberculosis and immune markers including humoral and cellular markers were evaluated 30 days post M.tuberculosis infections. Based on results, we found that high dose of subcutaneous infection produced chronic disease with significant (p<0.001) production of immune markers of infection like IFNγ, heat shock antigens (65, 71) and antibody titres against panel of M.tuberculosis antigens (ESAT-6, CFP-10, Ag85B, 45kDa, GroES, Hsp-16) all of which correlated with high bacterial burden in lungs and spleen. To conclude high dose of subcutaneous infection produces chronic TB infection in mice and can be used as convenient alternative to aerosol models in resource limited settings. Moreover assessment of immune markers namely mycobacterial antigens and antibodies can provide us valuable insights on modulation of immune response post infection. However further investigations along with optimization of study protocols are needed to justify the outcome of present study and establish such markers as surrogate endpoints of vaccine protection in preclinical and clinical studies in futur

PCR diagnosis of tick-borne pathogens in Maharashtra state, India indicates fitness cost associated with carrier infections is greater for crossbreed than native cattle breeds

Tick-borne pathogens (TBP) are responsible for significant economic losses to cattle production, globally. This is particularly true in countries like India where TBP constrain rearing of high yielding Bos taurus, as they show susceptibility to acute tick borne disease (TBD), most notably tropical theileriosis caused by Theileria annulata. This has led to a programme of cross breeding Bos taurus (Holstein-Friesian or Jersey) with native Bos indicus (numerous) breeds to generate cattle that are more resistant to disease. However, the cost to fitness of subclinical carrier infection in crossbreeds relative to native breeds is unknown, but could represent a significant hidden economic cost. In this study, a total of 1052 bovine blood samples, together with associated data on host type, sex and body score, were collected from apparently healthy animals in four different agro-climatic zones of Maharashtra state. Samples were screened by PCR for detection of five major TBPs: T. annulata, T. orientalis, B. bigemina, B. bovis and Anaplasma spp.. The results demonstrated that single and co-infection with TBP are common, and although differences in pathogen spp. prevalence across the climatic zones were detected, simplistic regression models predicted that host type, sex and location are all likely to impact on prevalence of TBP. In order to remove issues with autocorrelation between variables, a subset of the dataset was modelled to assess any impact of TBP infection on body score of crossbreed versus native breed cattle (breed type). The model showed significant association between infection with TBP (particularly apicomplexan parasites) and poorer body condition for crossbreed animals. These findings indicate potential cost of TBP carrier infection on crossbreed productivity. Thus, there is a case for development of strategies for targeted breeding to combine productivity traits with disease resistance, or to prevent transmission of TBP in India for economic benefit

Identification and characterization of a novel infectious bursal disease virus from outbreaks in Maharashtra Province of India

Aim: The study was undertaken to isolate infectious bursal disease virus (IBDV) from clinical cases in broiler and cockerel flocks of Maharashtra state, India, and its molecular epidemiological investigation. Materials and Methods: The morbid bursal tissues were collected from flocks suspected for IBD. The samples were subjected for virus adaptation in primary chicken embryo fibroblast (CEF) cells followed by confirmation by reverse transcription polymerase chain reaction (RT-PCR) for partial VP2 sequence and phylogenetic analysis. Results: The isolation of IBDV from field samples took seven blind passages for adaptation in CEF. The cytopathic effects included rounding, aggregation, vacuolation, and detachment of the cells. The RT-PCR showed amplification of 627 bp amplicon specific to the primers for VP2 gene fragment which confirmed successful adaptation and isolation of IBDV using CEF. The nucleotide and deduced amino acids based on phylogeny clustered the current isolate in a distinct clade with classical virulent and antigenic variants. It showed divergence from very virulent (vv) and vaccine strains of Indian origin. The isolate showed unique amino acid substitution at A329V as compared to all other IBDVs. The variation in key amino acids was reported at A222, I242, Q249, Q253, A256, T270, N279, T284, I286, L294, N299, and V329. It shared conserved amino acids at position A222, I242, and Q253 as reported in vvIBDV isolates. However, the amino acids reported at position T270, N279, T284, L294, and N299 are conserved in classic, antigenic variant and attenuated strains of IBDV. The amino acids at positions N279 and T284 indicated that the isolate has key amino acids for cell culture replication. Conclusion: The IBDV field isolate does not reveal the full nucleotide sequence signature of vvIBDV as well as vaccine strains. Hence, we can conclude that it might not belong to vvIBDVs of Indian origin and the vaccine strain used in the region. This may be suggestive of the evolution of the IBDV in the field due to the coexistence of circulating field strains and live attenuated hot strains, resulting into morbidity and mortality, warranting the need for safer protective vaccines, and implementation of stringent biosecurity measures to minimize loss to farmers