The Effect Of Different Periods of Heat Stress on Some Of The Haematological Picture At Broiler Chicks Vaccinated By Newcastle And Gumboro Vaccines

Abstract

This study was conducted to show the effect of the heat stress that will represented by 35 C° and for two periods : 8 hours in group (C) and 16 hours in group (D) with giving both Newcastle and Gumboro vaccines , and in addition to a control group (A) that will be represented by normal fowl breeding temperature according to its life stages without giving any vaccines and group (B) that will be giving all above vaccines breeding in normal temperature with comparing between all these groups with each others in order to know the effect of the heat stress on some hematological parameters in treated broiler chicks ,these parameters have been measured weekly by taking 15 birds from each group randomly to making these tests and depending their resulting in statistical test. The results of red blood cells count , blood haemoglobin concentration and packed cells volume were indicated lesser averages in the group (D) in comparing with other groups that beginning from the fourth week to the end of experiment duration , and the results of the groups (C) was mentioned a significant decrease in all parameters that have been referred to above in comparison with (A) and (B) groups as of the fourth week to the end of treatment period , and at the time when measuring of the H/L ratio ( the stress indicator ) averages in all experiment groups during the treatment weeks , the group (D) are counted their highest average at all treatment weeks in addition to the significant increasing in (B) , (C) and (D) groups in comparing with group (A) from the second weeks and to end of the last week from probation .