This study was conducted to ascertain anatomical variation in different body parts of Desi, Fayoumi, Cross (Rhode Island Red x Fayoumi) and Nick Chick laying hens. A total 16 laying hens of average body weight were selected using random numbers out of 2600 laying hens, slaughtered and eviscerated. It was observed that proportion of neck, ribs, breast, back, wings, thigh and legs out of aggregate weight was highest (51.74 plus minus 2.85) in Fayoumi hens. The proportion of liver, gizzard, heart and spleen combined weight was highest (6.05 plus minus 1.81) in desi hens. The proportion of non edible offals including trachea, lungs, kidneys, blood, feathers, head, crop, proventriculus, intestines, shanks, gizzard waste, skin, tail, testes, ova, oviduct and fat was estimated to be highest i.e. 46.60 plus minus 1.16 in Nick Chick laying hens. The anatomical variation in Desi and Fayoumi chicks was attributable to scavenging habit of these birds. The high proportion of edible offal in commercial Nick Chick hens may be ascribable to higher productive and reproductive traits.

This study was conducted to determine the optimum storage temperature for Rinderpest vaccine prepared on vero cells to know the shelf life of the vaccine. The vials were randomly selected from one batch of the vaccine, titrated and stored at minus 20 degree centigrade (Freezer), 4 degree centigrade (refrigerator) and room temperature. The titre was found to be 105.1 per ml. The vials stored at minus 20 degree centigrade & 4 degree centigrade were subjected to titration after an interval of six months for 3 and 2 years respectively. The vials stored at room temperature were tested after 4 weeks, 8 weeks and 12 weeks. Titration results indicated that the titre of the vaccine vials stored at room temperature decreased by 100.9 101.2 and 101.6 after storage time of 4 weeks, 8 weeks and 12 weeks respectively. The vials stored at 4 degree centigrade maintained their titre for a period of six months but after that the loss in titre was 100.4, 101.0, and 102.4 after storage time of one, one and half and two 2 years respectively. The vaccine vials stored at minus 20 degree centigrade maintained their original titres (initial titre of the vaccine) even after the storage for three years. It is concluded that vero cell adapted Rinderpest virus vaccine can be stored at 4 degree centigrade for a period of six months, however, at 20 degree centigrade it can be stored for three years without any adverse effect on titre.

The effects of melatonin and Light treatments on the reproductive performance of yearling Suffolk rams were investigated. The two groups (A, n = 8; B, n = 8) were given a priming period of long days (18 h Light (L): 6 h dark (D) during 1st February to 14th March. During 14th March to 9th September, group A was exposed to local light + melatonin Implants (Regulin) at 5 weekly intervals, group B was exposed to local light + melatonin Fed (M- 5250) alongwith the feed. The group (C, n = 8) in the local light during 1st February to 14th March and during 14th March to 9th September remained on local light + melatonin implants (Regulin) at 5-weekly intervals. However, the group (D, n=8) was treated as control and kept on local light environment (Lat. 51 degree 43'N) throughout the experiment. Testis diameter, sexual behaviours and semen quality were used to assess reproductive performances. The treatment to group A & B resulted in a significant advancement in high reproductive performance. The treatment to group C indicated that the abrupt application of melatonin in mid March resulted in a weak response in terms of all the criteria of assessment. The investigation indicated that seasonal fluctuations in reproductive behaviour and semen quality may be rephrased by the application of light and melatonin treatments and that these treatments may be considered for the preparation of rams for out of season breeding.

The quick diagnosis of Newcastle disease requires known serum against the disease. In this study, an attempt was made to raise anti- Newcastle disease virus hyperimmune serum in rabbits. Three different inoculum were prepared to inoculate in the rabbits; (i) Fresh harvested allantoic fluid containing Newcastle disease virus (NDV) Mukteswar vaccine strain; (ii) Freshly harvested ND virus pelletted through centrifuging at 40,000 rpm for two hours and resuspended in normal saline and (iii) Pelletted virus (centrifuged and suspended as in ii) with addition of incomplete Freund's adjuvant. It was observed during the monitoring of haemagglutination inhibition (HI) titre that the serum collected after series of inoculation of 1st and 2nd inoculum provided maximum titre upto 1:256. However, the serum collected after series of injection of 3rd inoculum gave maximum HI titre 1:1024. This study suggested that antigen containing incomplete Freund's adjuvant provided better immune response against Newcastle disease virus in rabbits.

This study was carried out for investigation of an outbreak in Karachi. A disease outbreak in poultry was reported during April, 2000 in Karachi. The main symptoms included respiratory distress, sneezing and gasping. Autopsy of dead birds showed tracheitis, air-sacculitis and involvement of lungs. The morbid material was collected for processing in the laboratory. During the investigation for isolation of pathogenic bacteria or virus, Ornithobacterium rhinotracheale was isolated on 5% sheep blood agar plates in an atmosphere containing 5-10% CO2 at 37 degree C and identified through biochemical and fermentation tests. A Lasota like virus was also isolated from the same material which showed HA activity but was found negative to Avian Influenza virus against known Avian Influenza serum. The isolated virus was sent to Central Veterinary Laboratory, Weybridge, U.K. which confirmed it to be Lasota virus having comparatively high Intracerebral Pathogenicity Index (ICPI) as 0.90. Attempts for the transmission of the disease in susceptible healthy broiler chicks was successful through aerosol route using combination of inoculum of the isolated bacteria and virus. On post-mortem of infected birds air- sacculitis, tracheitis and unilateral pneumonia were noticed. Again ORT and NDV were isolated from the material harvested from these chicks. According to the observations of these experiments, it was concluded that the isolated ORT had a triggering effect on Lasota virus or vice versa. The environmental temperature and other stress factors might have aggravated the disease problem.

An inactivated oil-based Newcastle disease vaccine was prepared using Mukteswar vaccine strain. The virus was propagated in 10-day old embryonating eggs and inactivated by 0.12% formalin for 48 hours at 37 degree C. The vaccine was formulated with 1 part antigen (aqueous phase) and 4 parts oil base. The oil base contained Tween-80 1%, Arlacel-A 10% and Mineral oil 89%. The stability of the vaccine was found satisfactory after 6 months and its viscosity and injectability was fairly ideal. The antigenicity of the vaccine was determined in 16 week-old pullets. The seromonitoring of the vaccinated and the control pullets was carried out for three months post- vaccination by Haemagglutination inhibition (HI) test. Blood samples were taken at fortnightly intervals. The Geometric mean HI titre of the vaccinated pullets on the day of vaccination 15, 30, 45, 60, 75, 90, 105 and 120 days post- vaccination was 18.4, 4.9, 87.5, 192.3, 257.6, 111.4, 91.7, 63.9 and 30.0. However, in non-vaccinated control pullets it was found to be 18.4, 3.7, 3.7, 4.3, 3.8, 4.0, 3.5, 2.8 and 2.3 respectively. The inactivated oil-based vaccine induced a marked antibody response which continued upto three months.

Nutrient broth with iron was used for obtaining high yields of epsilon toxin by clostridium perfringens type D. In this study iron balls, iron nails and ferrous sulphate were used as iron source. Results showed that the presence of iron nails and iron balls in nutrient broth slightly increased the bacterial growth but did not show increase in toxin production.

In this study twenty four isolates of Pasteurella multocida were collected from field out breaks of Haemorrhagic septicaemia (H.S) in cattle and buffalo from various regions of the country from 1991-2001. The isolates were subjected to detailed cultural, biochemical and pathogenicity test in albino mice. The stereotyping was done by indirect haemagglutination test for determination of their capsular antigen. Serologically all the isolates were classified on the basis of their capsular antigen as Carter Type B. All the twenty four isolates produced oxidase, catalase and indole and reduced nitrate. They did not produce urease. All the isolates fermented fructose, glucose, sucrose and sorbitol and mannitol with the production of acid whereas dulcitol, lactose, silicon were found negative. Variable results were found among isolates on the fermentation of arabinose and maltose. It was concluded that all the isolates were serologically and immunologically homologous to H.S. vaccine strain produced in the institute.