الفهرس 
Historical reviewOnly 14 pages are availabe for public view
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Abstract
This research is concerned with physiological and histological studies on the intestine of Streptopelia senegalensis aegyptiaca which is naturally infected with Cotugnia sp. and Killigreuia sp. 1- Using the in vivo perfusion technique, glucose, Na+, K+ Ca++ and C1- absorption was studied in the intestine of Strep tope1 ia senegalensis aegyptiaca (Egyptian dove) either uninfected or infected with the cestode parasite (Cotugnia sp.). The doves were anaesthetized and the abdomen was opened in the midline. Temperatre was maintained at 37”-38•‹Cb y the aid of 100 W. electric lamp. A small incision was opened in the intestine just distal to the gastroduodenal junction and another incision 5 cm. distal from the first one, was made. The intestine was cannulated at the two incisions. Worms were removed before beginning the experiment. 30 ml. of the perfusion fluid was circulated for 30 minutes with the aid of a syringe. Samples of the fluid were taken to determine glucose, Na+, K+, Ca++ and C1-. Nutrient concentrations (in mM) were 92 Nacl, 5 Kcl, 1.2 Mgcl2, 1.2 Cad2 and 5 glucose in the first perfusion fluid and Nacl and glucose were changed to 81.7 and 27 respectively in the second one. The perfusion fluid was isotonic to the physiological solutions of birds as to be 238 mOsmol. The absorptive capacity of the infected intestine was assessed using the two perfusion fluids at pH7 and pH6. The hydrogen ion concentration was adjusted in 1mM phosphate buffer. At the end of the experiment, parts of intestine were taken for determination of dry weight in mucosa and tunica muscularis. The volume of the test solution was calculated by measuring the concentration of phenol red spectrophotometrically. Absorbed amounts of measured elements were recorded in nano-moles per minute per milligram dry weight mucosa. a - Absorption from the first perfusion fluid: at pH7, the percentage of reduction in the absorptive capacity of infected part of intestine in comparison with non infected part was 82.83%, 63.08%, 68.35%, 71.20% and 67.49% in glucose, Na+, K+, Ca++ and C1- respectively. at pH6, the percentage of reduction in the absorptive capacity of infected part of intestine in comparison with non-infected part was 89.69%, 59.02%, 70.27%, 59.96% and 62.63% in glucose, Na+, K+, Ca++ and C1- respectively. b- Absorption from the second perfusion fluid: at pH7, the percentage of reduction in the absorptive capacity of infected part of intestine in comparison with non-infected part was 85.59%, 65.61%, 68.32%, 71.07% and 66.85% in glucose, Na+, K+, Ca++ and C1- respectively . at pH6, the percentage of reduction in the absorptive capacity of infected part of intestine in comparison with non-infected part was 86.07%, 62.44%, 70.21%, 66.35% and 68.83% in glucose, Na+, K+, Ca++ and C1- respectively. c- Water content percentage in tunica muscularis was reduced (60.65 f 7.51) in the infected part of intestine in comparison with the non-infected one (79.81 f 5.06). In mucosa, water content percentage was reduced (59.47 k 7.68) in the infected part of intestine in comparison with the non-infected one (80.93 f 5.56). Dry weight of tunica muscularis was increased (11.12 f 2.68) in the infected part of intestine in comparison with the non-infected one (4.77 f 0.97). Dry weight of mucosa was increased (8.19 f 0.80) in the infected part of intestine in comparison with the non-infected one (3.22 f 0.86) . 2- Histopathological studies: parts of infected and non-infected intestine were fixed in 10% formaline, dehydrated in a series of steps by means of alcohol, cleared in terpineol, washed by benzene immediately and then imbedded in paraffin wax (M. P. 54•‹C).C ross sections were cut to a thickness of 4-6 p , kept in an oven at 37•‹C for 48 hours. Haematoxylin and eosin, toluidin blue and P.A.S. stains were used . a- The total thickness of the infected part of intestine was increased. Hyperplasia of both tunica muscularis and mucosa was observed. The most conspicuous alterations were a marked crypt hyperplasia and a villous atrophy in terms of shortening and blunting of villi. Cross-sections of infected parts of intestine showed an inflammatory cellular infilteration in the mucosa and submucosa formed of eosinophilic cells and few lymphocytes. b- A number of mast cells increased in the infected anterior parts of intestine (400) in comparison with the non-infected parts (280). In the infected posterior parts of intestine, a number of mast cells increased (320) in comparison with the non-infected parts (200). It was expressed as (No. of mast cells per 10 crypts). c- Sections of non-infected. parts of intestine stained with P.A.S. showed deep crypt cells stain as a result of P.A.S. reaction which intensified as the cells approached the crypt neck and was pronounced on the villi, indicative of a strongly developed brush boder disaccharidase activity. Sections of infected parts of intestine showed poor reaction to P.A.S., patchy in places or even absent over the atrophic villi, indicative of a poorly developed or absent brush border disaccharidase activity .