Dr Khushi Muhammad, Dr Farhat Nazir Awan, Dr Akram Munir and Dr Athar Khan
In Pakistan, livestock is regarded as an important segment of daily life, as it is a main source of highly nutritive food in the form of milk and meat. It is also a source of draught power, especially in the rural family and agriculture setup. Animal skins are used in the leather and garment industry. Moreover, living animals and their by-products, including skins, are also exported to earn foreign exchange. The overall livestock contribution to the national GDP is 11.6 percent and its share in the agriculture sector is over 55.1 percent (Economic Survey of Pakistan, 2011-12).The province of Punjab is the most populous area in terms of animal and human populations. At present, the population of cattle and buffaloes in Punjab is 18.1 and 21.2 million. Over 71 percent of the buffalo population in Punjab is kept in irrigated areas, which contributes around 70 percent of Pakistan’s total milk production. Majority of buffalo is reared by small dairy farmers, who generally own five to eight buffalo heads for supplying milk in the urban market. However, the benefits from the livestock are hampered by many factors such as good supply of feed and fodder, poor husbandry practices and occurrence of infectious diseases like foot-and-mouth disease (FMD).Foot-and-mouth disease, commonly known as moun khur in the villages of Punjab, is a viral problem that affects cloven-footed animals, including cattle, buffalo, sheep and goats. There are seven different types of foot-and-mouth disease virus, but only three (O, Asia-1 and A) exist in Punjab. The virus is excreted in milk, urine, dung, semen and saliva of the infected animals and spread to other susceptible animal population through contaminated clothes, shoes, vehicles, veterinary instruments; introduction of infected cattle and buffalo; transferring of cattle and buffalo stock from an infected neighbouring village, shared drinking and grazing localities, wildlife and migrating birds.All breeds of the animal are quite vulnerable to clinical form of disease. The disease severity, however, is lesser in indigenous breeds than those of imported ones. The signs of disease appear in two to three days post exposure and last for seven to 10 days. The most common symptoms are; dramatic drop in milk yield, high fever that sustains for longer periods in the infected buffaloes than the cattle, excessive salivation and nasal discharge, smacking of lips, formation of vesicles on dental pad, tongue, and in the clefts or on coronet of the feet. Frequency of tongue lesions is higher in the cattle than the buffaloes. Healing of mouth lesions is quicker than the foot lesions. Further, healing of lesions is quite prompt and faster among buffaloes than that of cattle. Delayed healing of foot lesions may lead to lameness in the infected animals. In some cases, FMD may end up into an incurable condition commonly known as “panting”, which results from hormonal disturbance. Secondary bacterial mastitis and abortion commonly follows FMD signs. Young calves die due to destruction of cells of the developing heart muscles by the FMD virus. The disease is prevailing in all the districts of Punjab, which might be due to the movement of infected livestock from other provinces and neighbouring countries, non-availability or non-accessibility of veterinary health services and veterinary inputs by the livestock keepers of remote areas. Punjab has a relatively large animal health infrastructure in the public sector, The existing public service for animal health and livestock extension are weak and are constrained by poor mobility, lack of operational funding and training. The Veterinary Services have neither the power to enforce movement standstills when outbreaks take place, nor sufficient manpower or vaccine for routine use. Moreover, common village ponds and entry of new animals to the herd without adopting any precautionary measures to check the introduction of infection, are the other plausible factors enhancing incidence of the disease in animal population. The incidence of disease is comparatively higher in the canal irrigated areas such as Lahore, Multan, Gujranwala and Faisalabad divisions. These areas constitute an important milk production zone with a relatively higher population of elite dairy animals. Also, much of the area in the above mentioned districts is well connected to milk collecting centres, the higher density of susceptible animal population/km2, low coverage of FMD vaccination, occurrence of flood stress and movement of animal herds might be the major factors contributing to the higher incidence of disease in this milk producing zone of Punjab. In addition, infected animals excrete the virus in urine, dung, semen, or saliva that may contaminate its skin. Bathing, dung and urine of the affected domestic and wild animals may contaminate the water of rivers and canals and the virus may be carried to other areas.The adult buffaloes and cattle were at higher risk of contracting the disease as compared to their young stock and the reasons of increased susceptibility include stress factors such as pregnancy, malnutrition and low immunity level. Male animals of both the species are more susceptible to the disease than the female animals. The possible reason for a comparatively higher incidence might be that the farmers do not consider them as profitable as female animals and further they do not provide them the required attention since their birth. Moreover, males are used as work animals and kept in the field where they have more chances of contracting the disease from the grazing animals as compared to female animals, which are mostly stall-fed in urban areas.The incidences of the outbreaks increase gradually following the post-monsoon period. The greatest number of outbreaks is observed during the winter season, from December to February. Dry weather and dry wind with low temperature and moderate relative humidity during winter months might be the cause of rapid propagation of FMD virus among the susceptible animals.Experimental data show that animals reared on grazing have increased risk of getting FMD infection as compared to the animals kept on manger feeding. Grazing in communal areas presumably share drinking localities that is incriminated to be the cause of the disease transmission. Moreover, in common grazing facilitates, there are mixing of healthy and sick animals from neighbouring villages, which contributes to the FMD spread to the nearby villages. FMD generates significant economic losses by sharply reducing milk and meat production. Most affected animals fail to return to normal productivity even when cured. It also deprives infected countries of valuable export opportunities for many of the animal products that could potentially be sold in lucrative markets. A recent study conducted in Punjab showed that this disease caused a loss of Rs 4,615 per buffalo and with 10 percent incidence, the total buffalo affected with this disease are numbered at 2.12 million and the total loss is estimated at Rs 9,784 million.Vaccination as a control tool has been gaining favour, as a potentially more cost-effective approach for controlling the virus, reducing the economic loss to animal husbandry and contributing to improved food security. Pakistan has a capacity to produce maximum 2.0 million doses of the FMD vaccine at private and public biological production units. There is dire need to improve the quality and its production potential in the country to meet total requirements that is nearly 70 million doses per year. It is observed that introduction of new animals is the cause of FMD outbreak in the dairy animals. It is, therefore, recommended to vaccinate the newly purchased animals using multivalent FMD vaccine and keep them in quarantine for at least one month before letting them mix with the existing herd. At least 80 percent dairy animals including cattle, buffalo, sheep and goat may be vaccinated with adjuvant containing multivalent FMD-vaccine twice a year. Samples from at least 10 percent vaccinated animal population may be collected using probang, so that it is processed in the laboratory for the characterisation of FMD virus types using RT-PCR. Spray of either of the disinfectants, particularly sodium carbonate (4 percent) or halogens (payodine) at 0.5 percent, is recommended to inactivate FMD virus in the environment of dairy farms having infected animals. This will minimise the chances of dissemination of the virus to the nearby susceptible population.