Physiological Responses Of Nubian Goats To Haemorrhage As Affected By Bleeding Level , Age And Splenectomy

The studies were performed to investigate the effects of bleeding level, age and splenectomy on physiological responses to haemorrhage in goats. In experiment 1, the effects of two levels of bleeding (15% and 30%) were evaluated in adult goats.The magnitude of haemorrhage was expressed as percentage of initial total blood volume after plasma volume determination by dye dilution .The groups subjected to haemorrhage had higher rectal temperature (Tr), respiration rate (RR) and heart rate (HR) compared to the control ; the responses of these parameters were more marked with the higher level of bleeding .The treated groups had lower PCV, Hbconcentration and TLC compared to the control ; they were significantly lower with high level of bleeding compared to the control .The ratios of lymphocytes, monocytes and eosinophils decreased, whereas the neutrophil ratio increased in treated groups compared to the control . The treated groups had lower serum protein and albumin concentrations compared to the control. The serum urea and plasma glucose levels were higher in treated groups compared to the control and they increased with the increase of bleeding level. The treated groups had lower serum Na, Ca and Mg concentrations compared to the control . The levels of these minerals decreased with increase of bleeding level. In experiment 2, the effects of age of goats ( young : 3 months ; old :3 years) on physiological responses to 20% haemorrhage have been assessd. Both age groups had higher Tr, RR and HR in response to haemorrhage ; the increase inTr and RR was more pronounced in young animals. The PCV, Hb concentration and TCL were lower in haemorrhaged young and adult groups and the decline was more pronounced in adult goats. The decrease in lymphocyte and eosinophil ratios and increase in neutrophil and monocyte ratios were more pronounced in adult goats. Haemorrhage resulted in lower serum total protein and albumin levels in young and adult goats. The serum urea was higher in both age groups, and the rise was more pronounced in adult group . The post-haemorrhage increase in plasma glucose level was more marked in young animals compared to the adults.The serum Na level decreased in both treated age groups. In experiment 3, the effect of splenectomy on haemotological responses were investigated in adult goats. The splenectomized group maintained lower PCV and Hb concentration ; reticulocytosis was reported in splenectomized animals . After splenectomy, the lymphocyte and monocyte ratios were lower and the neutrophil and eosinophil ratios were higher comparedto the sham operated control . Splenectomy increased the thrombocyte count compared to the sham operated control . Splenectomy also resulted in non–significant decrease in serum total protein ; the serum albumin and urea levels were not influenced by splenectomy.The sham operated control and splenectomized animals had higher plasma glucose level after surgical operation. Serum Na level was not influenced significantly by splenectomy. In experiment 4, the effect of 25% haemorrhage on physiological reponses were evaluated in sham-operated and splenectomized adult goats. Haemorrhaged groups had higher Tr, RR and HR values; the rise in Trand RR was more pronounced in splenectomized animals . The PCV,Hb concentration and TLC were lower in splenectomized group immediately post-haemorrhage . The haemorrhaged groups had lower lymphocyte, eosinophil and monocyte ratios and higher neutrophil ratio ; the changes in these indices were more pronounced in splenectomized animals. The serum total protein and albumin levels were lower in haemorrhaged groups; the decline was more marked in splenectomized animals . The plasma glucose level increased significantlyin haemorrhaged animals ; the rise was more marked in splenectomized animals. Haemorrhaged groups had lower serum Na levels. In experiment 5, the effects ofaderenaline injection (1mg/ml) on physiological responses were investigated in normal and splenectomized animals. Normaland splenectomized groups had higher RR and HR ; the rise ofHR was more pronounced in spelenctomized animals. Adrenaline increased the PCV only in normal animals .The TLC increased inresponse to adrenaline in both groups; the rise was more marked innormal animals. In both groups, the ratios of lymphocytes and monocytes ratios decreased and neutorphil ratio increased in responseto adrenaline injection . Serum total protein level was not influencedby injection of adrenaline in both experimental groups. Adrenaline increased serum albumin level in normal animals only. Normal and spelenctomized groups had higher plasma glucose levels in response to adrenaline and the rise was more marked in splenectomized group. Serum Na level decreased in both groups after adrenaline injection. The results reported in thisthesis which were related to haematological changes and homeostatic mechanisms involved in restoration of normal blood constituents and influences of age and splenectomy were discussed in the light of previous findings in the literature . The studies indicate that the goat can be adopted as a valid research model in investigations of experimental haemorrhage and splenectomy. The findings have implications in the fields of veterinary haematology and surgery and comparative medicine