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The study evaluated deltamethrin resistance in Rhipicephalus sanguineus and Rhipicephalus (Boophilus) microplus tick populations of Kerala in India, using larval packet test (LPT). Dose response data were analysed by the probit method, the LC50 and LC95 of deltamethrin against ticks were determined by applying regression equation analysis to the probit-transformed data of mortality. In R. sanguineus, 50 per cent of isolates were found resistant at discriminating dose (600 ppm) by larval packet test. The p value obtained upon regression analysis was < 0.05 and was considered as significant. A majority of R. (B.) microplus were found to be susceptible to deltamethrin. However, these susceptible isolates survived doses which were twice the recommended doses (1.25 ppm – 100 ppm). The p value of isolates except isolate 1 and 5 were < 0.05 and statistically significant. The results highlight acaricide resistance to be one of the reasons for the alarming prevalence of tick-borne haemoparasites in Kerala and demand urgent interventions to ameliorate the resistance by alternate control strategies.

The rising prevalence of tick borne parasites and their economic impact on livestock production have often demanded better diagnostic tools and timely treatment options. The paper reports the molecular evidence of natural infections of Theileria ovis, T. lestoquardi and T. luwenshuni among goats in Kerala, south India, using PCR and RFLP. Concurrent infection of T. ovis and T. luwenshuni was also identified. Out of 150 samples studied, the PCR protocol was also found to detect a higher prevalence (59.3%) of theileriosis when compared to the detection of piroplasms (30%) in stained blood smears. In this study, the majority of goats were infected with T. ovis (75.28%), followed by those with T. luwenshuni (32.58%) and T. lestoquardi (7.86%). A high proportion of infected goats did not show any clinical signs indicating carrier status of infection. The carrier status of animals also signals the possible risk of disease transmission to healthy stock. However, a high incidence of caprine theileriosis, with significant haematological alterations including macrocytic hypochromic anaemia and thrombocytopenia, poses a potential threat to the goat population in the event of stress. Routine monitoring should be employed in farms for early detection and treatment of carrier animals., Rastuća prevalencija parazita koje prenose krpelji i njihov utjecaj na profitabilnost stočarske proizvodnje često su zahtijevali pouzdanije dijagnostičke alate i pravodobne načine liječenja. U ovom je radu prikazana molekularna identifikacija PCR-om i RFLP-om prirodnih invazija koza oblićima Theileria ovis, T. lestoquardi i T. Luwenshuni u Kerali u južnoj Indiji. Od 150 uzoraka analiziranih PCR-om utvrđena je viša prevalencija tajlerioze (59,3 %) u usporedbi s nalazom babezija (30 %) u obojenim krvnim razmazima. U ovom je istraživanju većina koza bila invadirana vrstom T. ovis (75,28 %), a zatim vrstama T. luwenshuni (32,58 %) i T. lestoquardi (7,86 %). Većina invadiranih koza nije pokazivala kliničke znakove tajlerioze. Također, supklinička invazija uputila je na potencijalni rizik prijenosa parazita na druge jedinke. Osim toga visoka incidencija tajlerioze u koza sa znakovitim promjenama u krvnim pokazateljima, uključujući makrocitnu hipokromnu anemiju i trombocitopeniju, potencijalna je prijetnja zdravlju koza u stresnim stanjima. Na farmama bi trebalo uvesti rutinsko praćenje radi ranog dokazivanja i liječenja latentno invadiranih životinja.

India has a wide range of agro-climatic zones which is highly conducive for a diverse range of vectors and canines are continuously exposed to the risk of spectrum of tick borne protozoan diseases. The brown dog tick, Rhipicephalus sanguineus is widely prevalent among dogs in Kerala and there is a high prevalence of this tick transmitted Babesia and Ehrlichia spp. infection. However, the incidence of Hepatozoon canis transmitted by the same tick species had not been reported in the state since 2004. Preliminary screening of client owned dogs revealed six dogs to be positive for typical gelatin capsule shaped gamonts of H. canis within neutrophils in blood smear by microscopic examination. A PCR assay was standardized to amplify a specific 737 bp fragment of 18S rRNA gene of H. canis. Phylogenetic analysis revealed closest relationship with West Indies isolate deposited at GenBank database. The present study records the molecular detection of this haemoparasite in the state, for the first time.

The distribution of ixodid ticks of the genera Rhipicephalus and Haemaphysalis spp. in tropical regions of India contributes to many serious tick-borne parasitic and rickettsial infections in domestic and wild canines. A preliminary molecular survey of the most prevalent haemoparasites in ixodid ticks of carnivores in Kerala, South India was undertaken using multiplex PCR. Babesia vogeli, B. gibsoni and Ehrlichia canis could be detected in R. sanguineus ticks, while H. bispinosa harboured B. gibsoni alone. Future investigations including transmission trials are to be undertaken to prove the vector potentiality of these ticks in this geo-climatic zone.

Doped lead–zirconate–titanate (PZT) thin films are preferred for the development of micro–electro–mechanical systems (MEMS)-based acoustic sensors because of their inherent higher dielectric and piezoelectric coefficients. Patterning process is used to develop such MEMS devices which is highly complex even for undoped PZT thin films; therefore, the problem is further cumbersome for doped PZT thin films due to the presence of added dopant elements and their associated chemistry. This paper presents patterning of strontium (Sr) and lanthanum (La) co-doped PZT thin film (PSLZT) deposited on platinized silicon substrate using wet and dry etching processes for fabricating a diaphragm structure with thickness of 15–25[Formula: see text][Formula: see text]m and diameter of 1.4–2[Formula: see text]mm, suitable for acoustic sensing applications. The effects of various etching conditions have been studied and the results are reported. It is found that the dry etching is the most suited process for realizing the piezoelectric MEMS structure due to its higher etching resolution. An appreciable etching rate of 260–270[Formula: see text]nm/min with smooth vertical sidewalls is achieved. The silicon diaphragm with patterned PSLZT thin film is found to retain more than 80% of its dielectric and piezoelectric coefficients and has a resonance of 1.43[Formula: see text]MHz.