ISOLATION, PURIFICATION AND STUDIES ON RADIATION INDUCED BIOCHEMICAL AND PHYSIOLOGICAL CHANGES OF BOVINE GROWTH HORMONE IN ANIMAL

Abstract

Growth honnone has a great importance in the field of animal physiology since it was the first honnone isolated from the pituitary gland, and found to be an adjuvant to increase productivity in milk and meat producing animals. So the main objectives of the present study were:

1- Extraction of bovine growth honnone (bGH) at the least of time and expense with good purity and potency. 2- VerifY the different biological effects of both the unlabelled and labelled fonn of the extracted bGH in rabbits as a model for meat producing animals.

Bovine growth honnone (bGH) was extracted by alteration in the hydrogen ion concentration of phosphate buffer extract of frozen pituitary glands and a subsequent precipitation with acetone and annnonium sulphate. The extracted bGH was dialyzed and lyophilized. In order to be sure that the extracted stuff is the bovine growth honnone, UV and infrared spectroscopy, PAGE chromatography and molecular weight detennination (SDS, PAGE) had been perfonned on the extracted bGH and standard authentic bGH. However, the extracted bGH was iodinated and its paper­ chromatography spectrum was carried out. 58 Male rabbits .of New-Zealand white strain of the age of two months and average body weight of 1400 gram were used to evaluate the biological effects of both unlabelled and labelled fonns of bGH. The rabbits were kept individually in metal cages, where commercial pelleted concentrate ration was offered to rabbits and fresh water was available all time, body weight gain and feed intake was recorded for an experimental period of one month (Group I). In this experimental the rabbits divided into four subgroups which injected with saline (controls), o.25 mg unlabelled bGH 0.5 mg unlabelled bGH and 0.25 mg labelled bGH for each rabbit daily for ten consecutive days.