Efficacy of herbal extracts and closantel against fenbendazole-resistant Haemonchus contortus.

This study assessed the efficacy of closantel vis-à-vis herbal extracts with known anti-parasitic properties, against fenbendazole-resistant nematodes in goats maintained under a semi-intensive system of management at the University goat farm, Jabalpur. Fifty goats were randomly assigned to five groups, each comprising 10 animals, irrespective of their breed, age and sex. Each animal in Group I, II and III was orally administered with aqueous leaf extracts of neem (Azadirachta indica) at 1 g/kg body weight, sitaphal (Annona squamosa) at 1.5 g/kg body weight and tobacco (Nicotiana tabacum) at 1 g/kg body weight, respectively, whereas Group IV was an untreated control group. Each animal in Group V was orally treated with closantel at 10 mg/kg body weight. During the course of the study, all animals were maintained under an identical semi-intensive system of management. Compared to the untreated control group (Group IV), there was no conspicuous reduction in post-treatment (day 10) faecal egg counts (FEC) in animals administered with the herbal extracts (Groups I, II and III), which is suggestive of poor anti-parasitic activity. However, using the faecal egg count reduction test (FECRT), the overall efficacy of closantel was recorded as 95.64%. This supports the rotational use of closantel as a preferred choice over the benzimidazole group of anthelmintics and/or herbal extracts to meet the acute challenge of in situ development of drug-resistant gastrointestinal nematodes, especially Haemonchus contortus.

An assessment of benzimidazole resistance against caprine nematodes in Central India.

Current status of resistance to benzimidazole (BZ) group of anthelmintic drugs against caprine nematodes in Central India at Amanala goat farm, Jabalpur, Madhya Pradesh (M. P.), was systematically investigated using faecal egg count reduction (FECR) test and egg hatch test (EHT). Besides, allele-specific PCR (AS-PCR) was deployed to ascertain the susceptible genotype (alleles) especially of the Haemonchus contortus. Randomly selected 30 goats, irrespective of age and sex, were divided into three groups of 10 each, to serve as treated and untreated controls. It was ensured that the animals were not administered with an anthelmintic drug for the past 3 months prior to undertaking the study, and faecal egg counts were estimated. FECR test evidenced fenbendazole resistance by partial elimination (24.90%) copro-egg counts in the treated group of animals vis-à-vis controls with a lower confidence interval of -26%. Further, EHT revealed ED-50 value of 0.335 µg of thiabendazole/ml, confirming benzimidazole resistance in the animals of that farm. AS-PCR showed that 62% of H. contortus larvae were homozygous resistant (rr), 24% heterozygous (rS) and 14% homozygous susceptible (SS). The genotypic frequencies of three genotypes (rr, rS and SS) were significantly (P < 0.01) different. The prevalence of benzimidazole resistance allele (r) was also significantly (P < 0.01) higher (74%) as compared to susceptible allele (S) (26%). The resistance to benzimidazole has been discussed while emphasizing improved managemental practices designed to reduce exposure of the goat population to parasites, minimize frequency of anthelmintic use at optimum dose and rotational use of different chemical groups of medicines with different mode of action, so as to overcome and combat the upcoming problem in the field.

Subclinical anaplasmosis in camel (Camelus dromedarius) and its successful therapeutic management.

On the Indian sub continent, dromedarian camel -'the ship of the desert' is an important constituent of the socio economic life style of nomadic owners in the semi arid to arid ecosystems. The animal suffers from a few parasitic diseases viz. surra, coccidiosis, sarcocystis, gastro intestinal concurrent metazoan infections, mange, nasal bots and ticks infestations. However, anaplasmosis in camel has not been reported so far from the Indian subcontinent. Systematic investigations of a 7 year male Jaisalmeri camel, with a clinical history of dullness, progressive loss of condition and stamina revealed subclinical Anaplasma marginale infection. The animal had depressed haematological indices, dry and constipated bowels, pale and icteric conjunctiva suggestive of anaemia. The animal positively responded to the specific integrated therapy. Reexamination of the animal on day 21 post-therapy revealed depressed haematological indices restored to normal levels and the erythrocytes were free from the pathogen. Neglected attention, poor and/or underreporting of camel diseases vis-a-vis economic significance of the versatile animal has been discussed. This appears to be the pioneer documentation of anaplasmosis in camels from Indian subcontinent.

Successful therapeutic management of concurrent subclinical Eimeria leukarti and Babesia (Theileria) equi infection in a mare.

The occurrence of Eimeria leukarti infection in equine is being sporadically documented despite its cosmopolitan prevalence. A Marwari mare, aged 3 years and 6 months and owned by a socio-economically weaker class of labourer of royal families, was suffering from non specific enteric disorders. Detailed systemic clinical examination of mare confirmed subclinical enteric infection with E. leukarti and piroplasms of Babesia (Theileria) equi in the circulating erythrocytes. She was therapeutically managed with synchronous administration of specific and supportive therapy with success. Non specific clinical manifestations of the disease in equines, its debatable pathogenic significance, predisposing immunosuppressive impact of concurrent B. (T.) equi in circulating erythrocytes and probable reasons for under reporting of the disease in equines, etc. have been discussed.

An occurrence of clinical eperythrozoonosis in a German Shepherd dog and its therapeutic management.

Eperythrozoon spp.-a rickettsial (Mycoplasma) pathogen of the mammalian erythrocytic cell membrane, has been recognised to cause non specific, sporadic, febrile and haemolytic clinical disease in a variety of livestock, especially food animals. However, clinical eperythrozoonosis in companion animals seems not documented so far. An adult male German shepherd dog, aged 10.5 years and weighing 45 kg with clinical history of persistent mild fever in morning hours, depression and anorexia for the past 5 days and nasal bleeding for the past few months, was presented to clinicians for therapeutic management. Microscopic examination of Giemsa stained blood smear evidenced characteristic light pinkish to blue stained cocci and/or short rod shaped pathogens identified as Eperythrozoon canis, nesting in the depressions on the periphery of erythrocyte cell membrane as well as extra cellular free bodies in the plasma. Rhinoscopic detailed investigation failed to demonstrate any lesion in the nasal passage that could be attributed to the frequent nasal bleeding for the past few months. The dog was subsequently therapeutically managed with success using specific therapy and followed by supportive therapy. Finally, the predisposing factors of the disease, reasons for frequent nasal bleeding, clinical course of the disease in canines and its public health significance vis-à-vis future projections have been discussed.

Acute bilateral proptosis in a cross bred calf naturally infected with Theileria annulata.

Ever since 1970, Bovine tropical theleriosis has been recognized major constraint to livestock improvement programme in the semi- arid and enzootic areas of Rajasthan. In contrast to other apicomplexan protozoan infections of blood, pathophysiological impact of Theileria annulata has been incriminated to in situ intra-leucocytic development of the pathogen. In continuation with recent manifestations documented on trans-placental T. annulata in a 3 day old cross bred calf and cerebral form of bovine theleriosis "Turning Sickness" in an adult cow, herein an another interesting manifestation of the disease "exophthalmos" incriminated to congenitally acquired T. annulata infection in a cross bred calf, its pathogenesis and impact are being presented and discussed.

Turning sickness in a cross bred cow naturally infected with Theileria annulata.

Bovine tropical theileriosis (BTT) has been since long recognized as a persistent major constraint on genetic improvement programme of native cattle breeds under "Operation Flood". The disease accounts for high mortality in dairy cattle especially calves. A cross bred cow (Rathi × Holestein), aged 3 years and weighing ~300 kg, owned by a person from weaker sections of the society, initially suffered from ruminal hypotonocity, severe dyspnoea, frothy discharge, lacrymation, cessation of defaecation, anorexia besides, icterus, mild form of anaemia and moderately elevated temperature etc., for the past 48 h. The cow suddenly developed pre mortal fall in temperature and neurological signs suggestive of posterior paresis. Ante mortem laboratory investigations revealed Koch Blue Bodies in the lymphocytes and Theileria annulata meronts in the erythrocytes. The cerebral form of BTT in the instant case was differentiated and discussed with other diseases causing analogous neurological signs.

Efficacy of fenbendazole, levamisole and ivermectin against gastrointestinal nematodes in Jamunapari goats.

Efficacy of fenbendazole, levamisole and ivermectin was checked in comparison to untreated controls in twenty Jamunapari goats, naturally infected with gastrointestinal nematode parasites. Faecal examination at day 0 revealed an egg per gram of 930 ± 175.1, 1350 ± 421.1, 1060 ± 224.9 and 800 ± 279.7 in group A, B, C and D, respectively having five animals each. The results of larval culture examination revealed the presence of Haemonchus, Trichostrongylus, Oesophagostomum, Bunostomum and Strongyloides spp. in these animals. Faecal egg counts of the animals treated with fenbendazole (group A), levamisole (group B) and ivermectin (group C) were reduced by 23.66, 63.70 and 98.11%, respectively on day 14 post-treatment.

Epizootiology, pathogenesis and immunoprophylactic trends to control tropical bubaline fasciolosis: an overview.

On the Indian sub-continent, nearly 5,000 years ago, the domestication of the riverine buffalo-the incredible Asian dairy animal was initiated. It plays a versatile role in socio-economic upliftment of its owners from the rural agricultural communities in Asian, African, South American and a few European countries. Comparatively, buffaloes are lesser evolved and susceptible to infectious diseases than cattle. However, poor body thermoregulation and wallowing nature predisposed them to snail borne infections, especially tropical fasciolosis-an incessant major constraint on buffalo production and improvement programmes. This review article is an insight into the global prevalence, varied epizootiological factors, offers possible explanation to pathophysiological clinical signs, deleterious effects of the tropical liver fluke, involving hepato-biliary system, haemopoitic system, endocrine glands and their secretions, oxidative stress, altered metabolism and significant fall in food conversion efficiency with unaffected digestibility of nutrients. Besides, the authors have briefly discussed and reviewed the developments and significance of successful immunodiagnostic approaches for detecting and forecasting the disease during early pre-patency and feasibility of developing a cost effective immunoprotection strategies against tropical fasciolosis.

Evaluation of dipstick-ELISA using 28 kDa Fasciola gigantica cathepsin l cysteine proteinase (FgCL3) for serodiagnosis of fasciolosis in naturally infected goats.

In the present investigation 100 goats presented for slaughter were used to evaluate the 28kDa cathepsin l cysteine proteinase (FgCL3) dipstick-ELISA for the diagnosis of fasciolosis. Presence of Fasciola gigantica worms in liver at the time of slaughter was taken as a gold standard for the evaluation of the assay. Faeces, blood and liver were taken from all slaughtered goats. Biochemical parameters and coprological examinations using sedimentation technique were also taken into consideration. Total serum proteins, albumin, mean values of aspartate aminotransferase and alkaline phosphatase of positive group were not significantly different from those of the negative group. The diagnostic sensitivity of dipstick-ELISA was higher than coprological detection of fluke eggs. However, specificity was equal for both the tests. The accuracy of dipstick-ELISA in detecting circulatory antibodies during the course of disease was higher than coproscopic examination. In conclusion, the FgCL3 antigen dependent dipstick-ELISA was more reliable and has better scope for field application in the endemic areas.

Intestinal helminths induce haematological changes in dogs from Jabalpur, India.

The effect of canine intestinal helminths on the haematological profile of 200 dogs, of both sexes and variable age, visiting university veterinary clinics for routine examination was investigated. The dogs were assigned to parasitized (n = 39) and non-parasitized (n = 161) groups of animals. Coprological examination revealed a 19.5% prevalence of different species of the helminths. Of these animals, 10.25% had mixed infections with Ancylostoma caninum, Toxascaris spp. and Dipylidium caninum. The intensity of A. caninum infection was the highest, with mean egg counts of 951.43 (standard error 88.66), followed by Toxascaris 283.33 (standard error 116.81) and D. caninum. The parasitized animals had significantly lower levels of haemoglobin, packed cell volume and total erythrocyte counts than non-parasitized animals (P < 0.01). Values of other parameters, except for lymphocytes and eosinophils, were not different between the two groups. Analyses of the haematological profile revealed normocytic hypochromic anaemia in the parasitized group of animals.

Serum enzyme and hematological profile of Fasciola gigantica immunized and experimentally infected riverine buffaloes.

Sixteen male, yearling Murrah buffaloes were randomly assigned to four groups of four buffaloes each. Each animal in Gr-I and II were immunized, respectively, with 4.8 mg of excretory secretory antigen and 1,300 microg Infection Specific Antigen, in three divided doses. Subsequently, each animal in Gr-I, II, and III was per os infected with 800 viable Fasciola gigantica metacercariae (bubaline origin) on week-6 after the start of the experiment, while animals in Gr-IV served as healthy controls. The aspartate aminotransferase (AST) and alanine aminotransferase (ALT) concentrations progressively increased during the prepatency and respectively attained the highest levels during week-6 and 8 post-infection (PI). The alkaline phosphatase (AP) exhibited elevated trends from eighth week PI onward and continued to be higher until the end (p < 0.05-0.01). With the cessation of traumatic activities of the diastomes, the AST and ALT levels declined yet were throughout significantly higher than the healthy controls (p < 0.05-0.01). In the immunized animals (Gr-I and II), the fluctuation patterns were similar but the values were significantly lower than the non-immunized (Gr-III) animals (p < 0.05-0.01). The elevated levels of the enzymes had positive correlation with depressed erythrocytic indices, leucocytosis, eosinophilia, necropsy worm recovery, and hepatic lesion score in the respective groups. The increased concentrations of the enzymes revealed two clearly demarcated stages: (a) remarkably elevated AST (40.8%) and ALT (140.0%) levels during the prepatency, signifying traumatic lesions inflicted by the F. gigantica adolescercariae and (b) the significant increase in AP (107.9%), suggestive of bile duct hyperplasia, cholangitis, periportal fibrosis, and biliary obstruction etc. from sixth week PI onward. None of healthy controls developed clinical signs and had normal hematological and serum enzyme profiles. Diagnostic significance of these marker enzymes in the disease forecasting and in time application of control strategies to combat tropical fasciolosis in buffaloes in the endemic areas has been discussed.

Tropical liver fluke-induced stress in experimentally infected and immunised buffaloes.

Disease-related stress associated with Fasciola gigantica infection was investigated in 16 male, yearling Murrah buffaloes. The animals were randomly assigned to one of four groups. Animals in groups 1 and 2 were vaccinated subcutaneously with 4.8 mg of excretory-secretory antigen (group 1) or 1300 µg infection-specific antigen (group 2), in three doses. Subsequently, all the animals in groups 1, 2 and 3 were infected orally with 800 viable F gigantica metacercariae (bubaline origin) on week 6 of the experiment. The animals in group 4 served as healthy controls. The clinical progress of the disease with respect to the adrenocortical response to infection was assessed periodically. The infected animals in group 3 developed characteristic signs of the disease and had the highest in situ fluke population (mean [se] 331.8 [19.5] ). One of the four animals in group 3 died on day 110 postinfection (PI). Animals that had been immunised before infection (groups 1 and 2) acquired adequate levels of immunity, were comparatively healthier and had significantly lower (P<0.05) fluke populations (mean [se] 194.3 [11.8] in group 1 and 164.5 [9.2] in group 2). Throughout the course of the disease, the group 3 animals had significantly higher cortisol levels than those in groups 1 and 2 (P<0.01) from week 4 PI onward. Although animals in the immunised groups (groups 1 and 2) had increased hormone levels, they were not significantly different from those in the control animals in group 4. Cortisol levels were higher during the early prepatency phase (weeks 1 to 6 PI) than during the late prepatency and/or patency phases of the disease. Cortisol levels in the healthy control animals in group 4 remained within the normal range.

Aberrant infestation of goat mandibles with Oestrus ovis larvae.

Nasal oestrosis is primarily an infestation of sheep. However, a non descript goat, aged three years was presented in lateral recumbency with clinical history of sneezing fits, laboured breathing, eroded mandibular lesions and bilaterally housing nasal bots therein. The first ever occurrence of nasal bots in an aberrant location (mandibles) in a goat, its therapeutic management and public health significance have been documented and discussed.

Immunodiagnostic/protective role of cathepsin L cysteine proteinases secreted by Fasciola species.

Cathepsin L, a major cysteine proteinase secreted by the parasite plays a pivotal role in various aspects of its pathogenecity. The enzyme takes part in nutrient acquisition by catabolizing host proteins to absorbable peptides, facilitates the migration of the parasite through the host intestine and liver by cleaving interstitial matrix proteins such as fibronectin, laminin and native collagen and is implicated in the inactivation of host immune defenses by cleaving immunoglobulins. Recently, Cathepsin L has been shown to suppress Th1 immune response in infected laboratory animals making them susceptible to concurrent bacterial infections. Accordingly, the protease has been recognized as an important target at which parasite intervention strategies should be directed. Fluke Cathepsin L cysteine proteinases are also reported as sensitive and specific markers for the immunodiagnosis of fasciolosis in ruminants. Further, vaccination of laboratory or large animals with these proteases resulted in a significant reduction in fluke burden and/or fecundity.

Effect of Fasciola gigantica infection on adrenal and thyroid glands of riverine buffaloes.

Effect of Fasciola gigantica infection on adrenal and thyroid glands was investigated using eight male, yearling Murrah buffaloes. The animals were randomly assigned to two groups of four buffaloes each (Group-A, infected; Group-B, non-infected control). Animals of Group-A were orally infected with 1000 F. gigantica viable metacercariae, keeping other four animals of Group-B as uninfected control. In the infected buffaloes, the clinical signs began appearing from 7th week postinfection (p.i.) and eggs were detected in the faeces between day 93 and 99 (95.5+/-1.25) postinfection (p.i.). The serum cortisol level, revealed a significant (P<0.05) rise during initial stage of the infection, followed by a continuous fall from 12th week onward. Peak cortisol level on 10th week (13.30+/-2.57ngml(-1)) was associated with eosinophilia (11.0+/-0.95%). However, non-infected controls maintained almost uniform cortisol levels (3.97+/-0.15-5.88+/-0.09ngml(-1)) throughout the period of the study. The pathological changes of adrenal glands were correlated with physiological dysfunction of the glands. The levels of T(3) and T(4) were significantly (P<0.05-0.01) low from 14th week onward and were synchronous with in situ migration, growth and development of F. gigantica. Significant reduction in the thyroid hormones was further supported by histopathological evidence of lymphocytic thyroiditis confirming hypothyroidism. A decrease in Hb, PCV, total erythrocyte counts and appearance of reticulocytes in the blood of the infected buffaloes suggested regenerative anemia, which could partly be due to hypothyroidism.

Effect of Fasciola gigantica excretory secretory antigen on rat hematological indices.

The present study was undertaken to investigate the effect of Fasciola gigantica excretory secretory antigen (Fg-ESA) on rat hematological indices. Fg-ESA was prepared by keeping thoroughly washed 40 F. gigantica flukes in 100 ml phosphate buffer saline (PBS) for 2 h at 37 degrees C, and centrifuging the supernatant at 12,000 g at 4 degrees C for 30 min. The protein content of Fg-ESA was adjusted to 1.8 mg/ml. The rats were randomly divided into two groups of six rats each. Rats in group A received 0.5 ml of Fg-ESA intraperitoneally (i.p.) for 7 days, whereas control rats in group B received 0.5 ml of PBS i.p. for 7 days. Hemograms of both groups were studied initially and on days 0, 2, 4, 14 and 21 after the final injection of Fg-ESA or PBS. Progressive and significant (p < 0.01) declines in the values of hemoglobin, hematocrit, and total erythrocyte count were observed without significant (p > 0.05) changes in the values of mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, or mean corpuscular volume in group A. Thus, we conclude that Fg-ESA induces normocytic normochromic anemia in rats.

Transcutaneous bilirubinometer in assessment of neonatal jaundice in northern India.

This study was undertaken from April 2002 to March 2003 to find out the correlation of transcutaneous bilirubinometer index with serum bilirubin levels in term, pre-term, small for gestation age babies, with and without phototherapy in neonates with jaundice. Another aim was to evaluate the transcutaneous bilirubinometer as a screening device for neonatal hyperbilirubinemia by finding the action levels for TcBI at forehead and sternum at which sample for serum bilirubin estimation should be taken. A total of 104 neonates were evaluated. Mean (SD) age (hours), birth weight (grams) and gestational age (weeks) were 100.4 (37.90), 2264.9 (634.4) and 36.8 (2.9) respectively. Mean serum bilirubin was 16.6 (6) mg/dL. Overall a correlation coefficient of 0.878 at forehead and 0.859 at sternum was observed. On excluding infants receiving phototherapy coefficients of 0.900 at forehead and 0.908 at sternum were noted. Correlation coefficient over forehead and sternum was found to drop from 0.85 to as low as 0.33 with duration of phototherapy exceeding 48 hrs. Lastly the determined action levels had a sensitivity of 77.8 to 100 % in assessing the need for serum bilirubin estimation in various groups.