This study was conducted to examine growth performance of black, dark brown and light brown varieties of Desi Generation-1 chickens obtained from selected Desi parents (originally procured from rural areas of Mianwali and Bhakkar districts) maintained at Poultry Research Institute, Rawalpindi. A total number of 900 day-old Desi chicks 300 each of black, dark brown and light brown varieties were divided into 3 separate groups and further sub-divided into 3 equal replicates. The experimental chicks were maintained on littered floor in 9 separate pens under optimal managemental conditions for a period of 12 weeks. They were fed ad libitum a balanced chick starter ration (from day- old to 8 weeks) and a grower mash (from 9 to 12 weeks). The birds had free access to clean and fresh drinking water. The results showed non- significant difference in growth rate, feed intake and feed conversion efficiency (feed/kg gain), whereas, significantly (P less than 0.05) lower mortality rate was recorded in Desi light brown chicks in comparison to other two varieties. The better growth performance in different varieties of Desi chicks observed during the present study than reported in earlier findings could be due to effect of genetic improvement through selection breeding carried out in the parent Desi flock.

This trial was conducted to study effect of freezing on quality of broiler meat after freezing. Meat samples were taken from two sites such as breast and thigh. The weight, moisture, protein, fat and ash contents were analyzed before and after freezing at -25 degree centigrade for 15 days using methods given in AOAC, (1990). It was observed that protein, fat and ash contents were not changed consequent to freezing. There was loss (P less than 0.05) in weight which can be attributed to drip loss when meat is thawed. This study provided evidence that there is no change in nutrients when meat is subjected to freezing.

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.