Maina Kumari1, Kamlesh Kumar Dhawal2 and Pratikshya panda3
1PhD Scholar, Division of Extension Education, Indian Veterinary Research Institute, Izatnagar, Bareilly (U.P.)
2Veterinary Officer, Animal Husbandry Department, Rajasthan
3 Assistant Professor, Division of Extension Education, COVS, Rampuraphul, Punjab
Introduction
The Indian dairy sector has experienced significant growth in recent years, with a growth rate (CAGR) of 6.47%, but our country’s population is predicted to expand at a rate of 1.29% per year with a population of 1.40 billion people. A rapidly growing population’s ever-increasing food demands have been met by the introduction of crossbreeds Consequent to the government’s sound interventions such as crossbreeding to upgrade the animal breeds, cognizable increase in production traits along with undesirable genetic changes led to higher disease incidence. As a result, on one hand, the dairy sector has put the country on the global map for being the world’s largest milk-producing nation, accounting for 22% of global production. On the other side, disease-related losses, as well as their prevention and treatment expenses are a stumbling block to livestock’s efficient growth. Among all the diseases of livestock, the parasitic infestations are responsible for huge economic losses to farmers.
Type of parasites and their transmission:
The parasites are the organism that lives and feeds on or in another species, identified as the host, from which they get nutrition. Endoparasites (those that reside inside the host’s body) and ectoparasites (those that live on the host’s exterior surface) are the most common types of parasites. Haemoparasites are the parasites which live in the blood of the host. External parasites of dairy animals in India include insects such as stable flies, horn flies, face flies, mosquitoes, horse flies, cattle grubs, and ticks as well as lice and mites are the major
Adverse effects of parasites
Endoparasites: Subclinical infections of endoparasites are responsible for high morbidity and mortality in young animals and enormous production losses in adults. Gastrointestinal parasitic infestations are responsible for significant economic losses to farmers by causing reduced or no fertility, lowering work capacity, declining food efficiency and reduced weight gain, lowering milk production, increasing the cost of treatment and mortality in heavily parasitic infected animals. In the dairy industry, pharmaceutical products for nematode parasite management are predicted to cost USD 2.5 billion.
Ectoparasites: External parasites particularly ticks, cause direct loss through blood loss, tick worry, damage to the hide, toxins production, loss of body weight and milk yield. Moreover, indirect losses caused through the transmission of disease-causing agents, act as a vector for protozoa, predisposing animals to secondary disease conditions like screw-worm myiasis and dermatophytosis. The most common and serious combined effects caused by TTBDs in the Indian dairy system are depreciation of hide up to 20 to 30%, reduction in milk yield (14 %) and an aggregate loss of 3000 million units of hide per year. According to the FAO (2004), 80% of the world’s animals are exposed to tick infestation, with an appraised cost of $7.3 per head per year.
Transmission of parasites
Transmission of the parasites occurred through the ingestion of their eggs or infective larval stage with the contaminated pasture, water, soil, human hands, tissues of infected vertebrate intermediate hosts, skin penetration, transplacental as well as arthropod and gastropod intermediate hosts.
Management of Parasites
- To maintain the proper humidity and air circulation, the animal shed must be well ventilated and lightened
- Always keep the optimum number of animals in the animal shed
- It is not advisable to feed the animal on the ground. Grain, hay, and mineral feeding should be done in feeders that aren’t easily contaminated by faeces
- Water should be clean and free of faeces, and the watering tough should be in well-drained areas with gravel or even concrete floors
- The presence of good drainage in the animal shed reduces the parasites’ chances of surviving
- Quarantine the newly introduced animals for 4–6 weeks and, if necessary, administer anti-parasitic medications
- Always maintain the manure in a heap to ensure that parasite eggs, larvae, cysts, and other stages are killed by the heat generated during composting
- The bedding material, which acts as a major source of parasitic diseases such as winter coccidiosis, should be allowed to decay with the manure for improved parasite management
- The parasites are also eliminated by applying nitrogen fertilizers like urea (1:25) on the surface of manure
- The cattle can graze on fresh or clean pasture (pastures that haven’t been grazed in 6–12 months)
- To acquire parasite-free grazing land, regular removal of old or grazed pasture should always be practised
- Allow the optimum number of animals to graze in a given area of pasture
- Allow livestock to graze in a field up to 10 cm off the ground (because most of the parasite resides up to 5 cm length of grasses)
- Practices pasture rotation and alteration (first allow grazing by cattle and buffalo then sheep and goat)
- Practices grazing by age group (graze different age group animals in different fields)
- Adoption of the breeds that are resistant to the parasitic infestation
- Use anti-parasitic drugs for deworming and dipping in a strategic way
Chemical treatment of parasites and related issues in the livestock sector
Along with other infectious diseases, managing the multifaceted worries caused by parasite infestations is extremely grim. For control of endoparasites, farmers have principally relied on the use of anthelmintic drugs. The majority of the farmers solely rely on pharmaceutical acaricides for the control of ticks, in the form of sprays, dips in solution and pour-on formula. This is a practice that favours a condition of the emergence of multiple resistance in animals. On the other hand, the long-term use of drugs is frequently escorted by some serious problems such as contamination of the environment, milk and meat with drug residues. According to various research reports around the world, drug residue in animal products ranges from 5.2 to 27.48%.
Anti-parasitic drug resistance and its current scenario in India
Anti-parasitic resistance is “the ability of parasites to survive doses of drugs that would normally kill parasites of the same species and stage”.
In India, the first case of anthelmintic resistance as stated in H. contortus against benzimidazole and phenothiazine drugs from organized sheep herds in the Uttarakhand area. The rate of developing resistance against parasitic drugs was reported as an alarming situation in India, which limits the available options for treatment. A study by Ahanger et al. (2015) in the Jammu and Kashmir state reported that the majority of owners faced treatment inefficiency against the chemicals like Ivermectin, Deltamethrin, Cypermethrin, Flumethrin and Amitraz. The results of the reports illustrate that the whole country has been trapped under the resistance fear that negatively affects the livelihoods of millions of small-scale producers. The annual cost of resistance in Europe is €38 million and this cost could upsurge as helminth populations become resistant to numerous anthelmintic drugs. Thus, there is an instant necessity to strengthen the resistance monitoring system, pertinent broadcasting and extension of available knowledge to avoid an unmanageable situation.
Points should be followed to overcome anti-parasitic drug resistance
- No anti-parasitic drug utilization by farmers without prescription from authorized veterinary professionals
- Administer medicines at the correct concentration and dose (according to body weight of the animal)
- Avoid under-dosing and overdosing of anti-parasitic drugs that may lead to resistance development
- Deworm the animals according to a schedule
- Calf: First dose at14-21 days and booster at 35-42 days
- Pregnant animals: deworm the animals in the third trimester when the parasitic load is more due to stress in animals
- Adult animals: only deworm the animal when they show symptoms of parasitic infestation (diarrhoea, weakness, rough hair coat etc.)
- Avoid mass anti-parasitic treatment in animals (administer drug case-by-case)
- Annually rotate the anti-parasitic drugs (do not use the same drug for a longer period of time)
- Do not give medicated feed to animals
- Use ethnoveterinary medicines for parasitic treatment in animals
Vaccinate the animals against ticks and other parasite