Avian Coccidiosis: A Major Threat to the Indian Poultry Industry and Modern Solutions for Prevention.

Introduction:

The Indian poultry sector currently contributes approximately 20 percent to the total gross value added from the country’s livestock industry. This significant contribution is fuelled by the escalating per capita net domestic income, rising per capita private final consumption expenditure and ongoing modernization trends (Sharma et.al.2023).

Coccidiosis is one of diseases of poultry that play inhibitory role in the growth of poultry industry. Coccidiosis is responsible for 6–10% of all broiler mortalities and the global economic losses occur as a result of reduction in growth rate and feed conversion efficiency. It is a disease complex of poultry caused by different species of parasite Eimeria. It inflicts the birds in both clinical and sub-clinical forms. The clinical form of the disease manifests through prominent signs of mortality, morbidity, diarrhoea or bloody faeces and sub-clinical coccidiosis manifests mainly by poor weight gain and reduced efficiency of feed conversion and gives rise to highest proportion of the total economic losses. (Bera et.al.2010).

Etiology:

Coccidiosis results in heavy morbidity and mortality of birds between 3 to 18 weeks of age and seven Eimeria species infecting the chicken include Eimeria acervulina, Eimeria bruneti, Eimeria maxima, Eimeria mitis, Eimeria necatrix, Eimeria praecox and Eimeria tenella. Eimeria acervulina and E. maxima are the most prevalent species, while Eimeria tenella being the most pathogenic species (Yaqub et.al.2023).

Life cycle:

The life-cycle is short and starts with the bird ingesting sporulated oocysts. The sporulated oocysts contain four sporocysts, each containing two sporozoites and the mechanical and acidic environment in the gut result in the release of these sporocysts and sporozoites into the gut. The sporozoites invade the duodenal mucosa epithelial cells before undergoing phases of growth and multiplication with periodic release of merozoites into the gut. Merozoites develop within the duodenal cells as gametes, in the form of both macro- and microgametocytes. These develop into a zygote and then an oocyst which is shed in the faeces. These oocysts require moist conditions to undergo sporulation, a process that requires oxygen and takes about 24 hours, at which point they become infective (pal et.al.2023)

The severity of coccidian infection depends on the age of the birds, Eimeria species, number of sporulated oocysts ingested, immune status of the bird and environmental management. Coccidiosis in chickens is characterized by dysentery, enteritis, emaciation, drooping wings, poor growth and low production, with a high rate of mortality and morbidity (pal et.al.2023).

E. tenella primarily targets the ceca, causing blood accumulation and cecal cores. E. necatrix affects the proximal and mid small intestine, leading to “salt and pepper” lesions, while E. acervulina is the most common, infecting the upper small intestine with distinctive whitish patches. E. brunetti, E. maxima, E. mitis, and E. praecox affect various parts of the intestine with varying severity, while E. hagani and E. mivati, less distinct, develop in the proximal small intestine.

Prevention and control:

Layers and breeders raised on floor litter require protective immunity against coccidiosis. Traditionally, these birds received a suboptimal dose of an anticoccidial drug during early growth, with the hope that repeated exposure to wild coccidia would naturally enhance their immunity. However, this approach has been less than fully effective due to challenges in controlling the various factors that influence coccidia reproduction in practical settings. While anticoccidial drugs have been the preferred method for protecting these birds. The emergence of resistance in coccidiosis, is mainly due to the continuous and improper use of anticoccidial drugs in feed. Over time, this has led to drug-resistant strains of the parasite ‘Eimeria’ in various countries, making it harder to control the disease. Some drugs, like diclazuril and decoquinate, remain effective initially but resistance can develop with use. Cross-resistance among certain drugs has also been observed, complicating treatment efforts (Usman et.al. 2011).

Vaccination programs are becoming increasingly popular. Advances in vaccine administration techniques and the selection of specific coccidia strains are making vaccination more viable, particularly in broilers. Vaccination is key in controlling coccidiosis in poultry, stimulating an immune response through B and T lymphocytes to protect against Eimeria infections. Vaccines containing oocysts from Eimeria strains which are effective in triggering comprehensive immunity.

Stallen South Asia Pvt.Ltd. offering a unique vaccine against coccidia which is Livacox Q.

Composition: it is quadrivalent live attenuated coccidiosis vaccine for breeders and layers containing attenuated line of economically important species in breeders and layers namely Eimeria acervulina, E.maxima, E.tenella and E. necatrix.

1 dose (0.01ml) of Livacox Q provides 300-500 live sporulated oocytes of each attenuated line of E. acervuline, E.maxima and  E.tenella  and 100 live sporulated oocytes of attenuated line of E. necatrix in a 1% w/v aqueous solution of chloramine B.

Indication: Immunization of commercial breeders and layers against coccidiosis caused by E. acervulina, E. maxima, E tenella and E. necatrix in domestic poultry (Gallus domesticus). Immunity develops 14 days after vaccination and remains active during the bird’s whole life.

Contraindications: Do not use with food and water that contain anticoccidials, sulphonamides or any other agent having anticoccidial activity. Feed and water provided to birds 2 days before and during the first 14 days after vaccination must be free of the aforementioned substances.

Dosage

1 dose per chicken (0,01 ml)

1 ml =100 doses

Storage

Do not freeze.

The vaccine must be stored in a dark and dry place between +2 °C and +8 °C.

Temperature of vaccine during transport must be maintained within +2 °C and +8°C.

Do not allow contact with freezing unit of refrigerator.

Used or partially used containers should be disposed of as per local laws and regulations.

Keep out of reach of children.

Expiration: 9 months from the date of manufacture (see Exp. Date on bottle).

Withdrawal period: Zero days.

Precautions

 Vaccinate only healthy chicks kept under good management conditions.

 Dilute the vaccines only in fresh drinking water.

To generate a booster antigen, birds must have access to litter for a minimum of 10 days after vaccination.

Shake bottle thoroughly before opening and mixing with water.

The droppings of the birds serve as a reservoir of coccidial oocysts for automatic ‘revaccination’. In the case of any mortality, chicken carcasses sent to diagnostic laboratory for post-mortem must be marked ‘LIVACOX vaccinated”.

Packaging:

10 mi (1000 doses) in a screw-capped polyethylene bottle.

50 ml (5000 doses) in a screw-capped polyethylene bottle.

10 bottles of either size is packed in one carton.