OBJECTIVES -
To develop / improve vaccines and other prophylactic measures against major livestock and poultry diseases
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To develop efficient and cost effective diagnostic methods for animal diseases.
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Investigation of pathobiology and epidemiology of economically important animal diseases for developing better control measures.
ACHIEVEMENTS
Calf mortality
Average calf mortality rate in cattle is 29.1% and in buffaloes 38.8%. Most of the deaths occur in Ist 3 months of age and gastrointestinal and respiratory diseases take the heaviest toll. Bacteria associated with important bacterial causes of calf mortality i.e. colibacillosis and salmonellosis were isolated and most effective drug determined to control calf diarrhoea. Transfer of Toxocara and Strongyloides (the important parasitic causes) to young buffalo calves through colostrum and in utero was also defined. Based upon these findings, a package of technology was developed to control calf mortality which has been successfully adopted by common farmers.
Mastitis
The study of inflammation of the udder in cattle and buffaloes indicated the causative bacteria and the most effective drug to treat this infection under local conditions. A test for early diagnosis at sub-clinical stage was developed/adopted using sodium hydro-oxide solution for cattle and buffaloes and was found to be very effective in the control of this disease. About 67% animals with sub-clinical mastitis were found to be treatable using immuno-potentiating drugs without use of antibiotics. This information has been successfully disseminated among related farmers.
Development of Haemorrhagic Septicaemia (HS) Vaccine
An oil adjuvant vaccine for haemorrhagic septiceamia (Gulghotoo) HS was developed and tested extensively in laboratory and farmers' animals. This vaccine provides one year protection with protective efficacy of >95% as compared to presently available alum precipitated vaccine which provides protection for 4 months with protective efficacy of 67%.
The studies also helped in developing vaccination schedule in young calves. Transfer of maternal antibodies against HS indicated that first vaccination should be given at 3-4 months age.
A combined vaccine for HS and Foot and Mouth Disease was also developed and found to be effective in laboratory animals. Development of this vaccine will reduce the frequency of vaccination from 4 shots per year to only one shot per year. Field trials in
this regard are still on going.
A live aerosol HS vaccine has also been developed. The recent trials carried out at Karachi and Islamabad Capital Territory in this regardrevealed that single dose of vaccine gives protective immunity for one year in cattle and buffaloes.
Twelve different field isolates and a vaccinal strain of Pasteuralla multocida were chrecterized by Restriction Frame Length Polymorphism and protein profiling pattern. No difference was observed among these isolates which reflect that the current strain used for vaccine production is still efficacious to protect cattle against field strain of HS.
Brucellosis in Cattle and Buffaloes
Sero-diagnostic assay (ELISA) was developed for detection of Brucella abortus antibodies in buffaloes. Efficacy of B. abortus strain 19 and RB 51was evaluated in buffaloes of various age groups. Calf hhod vaccination with strain 19 was recommende3d while RB 51 vaccine can be used at any stage. Isolation and identification of B. abortus from field cases was carried out. Sero-prevalence of brucellosis in private and public sector farms in Punjab was determined and control strategies were proposed.
Control of Ecto and Endoparasites
Parasites of domestic animals in Islamabad and Rawalpindi area were identified and a package of technology developed to control these parasites in small ruminants was developed. This control has been successfully demonstrated to a large number of farmers in the area. Warble fly is an ecto-parasite of ruminants. It is prevalent in all the four provinces of Pakistan. Its intensity is higher in hilly areas as compare to plain areas.The species of warble infesting goats and cattle in the country were identified as Przhevalskiana silenus and Hypoderma lineatum respectively. Control of this infestation based on single injection of ivermectin in the last week of October in goat and 1st week of September in cattle was highly effective under our field conditions. This disease control strategy has been disseminated to the farmers.
Hydropericardium Syndrome (HPS) in Broilers
Hydropericardium syndrome is a fatal infectious disease of chicken. The vaccine to control this disease was developed by the scientists of this institute. This vaccine saved broiler poultry industry from total collapse. The vaccine technology in this regard was transferred to the private sector, and is now being manufactured at a number of government and private institutes.
Association of adenovirus with hydropericardium syndrome was first time determined by the NARC scientists. HPS agent was found to be immuno-suppresive in chicks. Tissue tropism of the HPS associated adenovirus was also determined. The virus has also been characterized on molecular basis through its protein profile and comparison with other adeno viruses. Mathematical models of spread rates of HPS agent(s) were also developed for helping in the development of appropriate control strategy.
Avian Influenza Monitoring and Control (Bird Flu)
Avian Influenza is a highly contagious infection of poultry, which can be transmitted to humans under under some specific conditions. A national programme for prevention and control of Avian Influenza is being run at the National Reference Laboratory for Poultry Diseases, NARC. Under this programme 11 Avian Influenza surveillance centers are being co-ordinated throughout the country for diagnosis, control and monitoring of Avian Influenza in poultry.
Collaborative research work is also being carried out for the development of molecular diagnostic assays and vaccine against bird flu. This is being done in collaboration with research laboratories in UK, Italy and USA. Based on the early warning surveillance mechanism of this disease it has become possible to detect and contain the viral presence in poultry. This helps in devising appropriate control measures.
National Reference Laboratory for Poultry Diseases
for helping the poultry industry of Pakistan, a National Reference Laboratory for Poultry diseases (NRLPD) has been established at the Animal Health Programme here at Animal Sciences Institute, NARC. This laboratory is coordinating with number of diagnostic laboratories of provinces for proper disease diagnosis, staff training and devising disease control strategies.
Epidemiology of Peste des Petits Ruminants (PPR)
Peste des petits ruminant (PPR) is an acknowledged acute and highly contagious newly emerging/ evolving disease of small ruminants (sheep and goats). It is capable of destroying whole of the immunologically naive host population by provoking epidemics and pandemics subsequently damaging economy, undermining food security and livelihood of the poor farmers. In Pakistan PPR causes economic losses of Pak Rs. 20.5 billion annually. Keeping in view the economic importance and Transboundary nature of the disease, some studies are being undertaken to study the epidemiology of PPR in Pakistan.
Awareness campaign (training workshops, extension materials) was launched throughout the country to sensitize the field staff by holding workshops and publishing extension material. PPR virus has so far been isolated from four outbreaks in Pakistan in recent times. Epidemiological factors responsible for persistence/transmission of virus have been identified in such outbreaks. Development of a cost effective assay (haemagglutination -HA-test) for PPR diagnosis is now inder process.
Disease Monitoring Models
Models of Livestock and Poultry disease monitoring systems were established and demonstrated to provincial departments. Breeding problems, Mastitis and gastro- intestine problems were the highest reported conditions in adult large ruminants. The cow and buffalo calves frequently had gastro-intestinal and respiratory disease conditions. Most of the calf crop of both species was lost within the first 3 months of life. In small ruminants diarrhoea and respiratory disorders were wasting disease entities.
PUBLICATIONS
SCIENTISTS STAFF
1. Dr. Khalid Naeem, CSO - Virologist/Programme Leader
2. Dr. Muhammad Qasim Khan, SSO - Parasitologist
3. Dr. Manzoor Hussain, SSO (On Leave) - Virologist
4. Ms. Rakhshinda Muneer, SSO - Bacteriologist
5. Dr. Aamer Bin Zahur, SSO - Microbiologist
6. Dr. Zaheer Ahmed, SSO - Virologist
7. Dr. Zahida Fatima, SO - Epidemiologist
8. Dr. Aman Ullah, SO - Epidemiologist
9. Dr. Hamid Irshad, SO - Virologist
10 Dr. Umer Farooq, SO - Virologist
11. Ms. Naila Siddique, SO - Molecular Biologist
12. Mr. Muhammad Jahangir, TO
