Theses and Dissertations Collection

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    The organisation of the enteric nervous system in the pig and goat, and changes induced by granulomatous inflammation in pigs infected with schistosoma japonicum
    (The Royal Veterinary and Agricultural University Copenhagen, Denmark, 2001) Begira, Onesmo Balemba
    This thesis is composed of four chapters, six papers and a summary in English as well as in Danish. In chapters one to three the literature in the fields of study has been reviewed and the objectives set forth in the current investigation and what was achieved are highlighted. Chapter four gives a brief overview discussion of the results and perspectives. The remaining part of the thesis is composed of publications/manuscripts describing findings from the current work as well as respective discussions and conclusions and will be referred to as papers I-VI in the text. Paper I deals with the organisation of the enteric nervous system in the small intestine of the pig with emphasis on the submucous and mucous plexuses. Paper II gives an insight of the organisation of the ganglia, isolated neurons and subplexuses in the mucous plexus in the intestine of the pig. Paper III presents the organisation of the enteric nervous system in the goat with emphasis on the subdivisions in the outer and inner submucous plexuses and salient features to differentiate them as well as the extent of ganglia and isolated neurones in the mucous plexus. Intra-plexus variations along segments, inter-plexus variation with respect to the size of ganglia nerve stands and neurons are elaborated. Paper IV focuses on problems associated with methods used to quantify neurons, enterochromaffin cells as well as estimation of the surface area of Peyer’s patches in the gut in the previous studies. A simple, cheap, unbiased sampling method is demonstrated using the pig jejunum as an example. Papers V and VI present findings on the plasticity of neurochemical contents in the enteric nervous tissue in the caecum and colon of pigs infected with Schistosoma japonicum. Paper I: O.B. Balemba, M.-L. Grpndahl, G.K. Mbassa, W.D. Semuguruka, A. Hay-Schmidt, E. Skadhauge, V. Dantzer. The organisation of the enteric nervous system in the submucous and mucous layers of the small intestine of the pig studied by VIP and neurofilament protein immunohistochemistry. Journal of Anatomy 1998; 192: 257-267. Paper II: O.B. Balemba, A. Hay-Schmidt, R.J. Assey, C.K.B. Kahwa, W.D. Semuguruka, V. Dantzer. An immunohistochemical study of the organisation of ganglia and nerve fibres in the mucosa of the porcine intestine. Autonomic Neuroscience: Basic and Clinical. (Submitted). Paper III: O.B. Balemba, W.D. Semuguruka, A. Hay-Schmidt, V. Dantzer. The organisation and variations of ganglionated plexuses of the enteric nervous system in the goat. Journal of Anatomy. (Submitted). Paper IV: O.B. Balemba, A. Hay-Schmidt, V. Dantzer, H.J.G. Gundersen. A very simple and efficient stereological sampling scheme for large mammalian gut, with estimation of the total number of specific neurons in distinct plexuses using unbiased principles. (Draft). Paper V: O. B. Balemba, W. D. Semuguruka, A. Hay-Schmidt, M. V. Johansen, V. Dantzer. Vasoactive intestinal peptide and substance P-like immunoreactivities in the enteric nervous system of the pig correlate with the severity of pathological changes induced by Schistosoma japonicum. International Journal for Parasitology. (In press). Paper VI: O.B. Balemba, K. Mortensen, W.D. Semuguruka, A. Hay-Schmidt, M.V. Johansen, V. Dantzer. Neuronal nitric oxide synthase activity is increased during granulomatous inflammation in the colon and caecum of pigs infected with Schistosoma japonicum. Autonomic Neuroscience: Basic and Clinical. (Submitted).
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    Development of the intestinal tract lymphatic system in goats
    (Sokoine University of Agriculture, 1989) Assey, Remmy John
    Gross and microscopic studies of the Gut-Associated Lymphoid Tissue (GALT) and Mesenteric Lymph Nodes (MLN) were performed on ten fifteen 3 months old kids and fifteen 8-12 months old goats. Morphological changes of the intestinal tract lymphatic system with age, the relationship of morpholo­ gical changes between and within intestinal lymphoid organs in particular the Peyer's patches and the MLN during growth, possible role of the Peyer's patches in the immune system of the caprine and lymph flow from the intestine were studied. Kids were born with an average of 35 histologically mature Peyer's patches in the jejunum (Jejunal Peyer's patches-JPP) which ranged in size from five follicles to 4.5 cm. long patches. A long Peyer's patch whose width was not uniform was also found in newborn kids. j e j unum It was broader caudally and it extended from the to the ileocecocolic junction (Jejunal-Ileal Peyer's Patch-JIPP). The average length of the JIPP was 0.83 m. Two round Peyer's patches were found in the colon (Colon Peyer's Patches - CPP ). The Peyer's patches were present on 17% of the intestine length. The shape of the follicles and the interfollicular area breadth were different in the JPP, JIPP and CPP. Interepithelial lymphocytes (IEL) number on domes decreased from cranial end to caudal end of the intestine. The trend was not observed on the villi epithelium. Intestinal tract villi epithelial cells in kids which had not suckled were columnar and had their nuclei in the apices. In average newborn kids had 5(1— 10) jejunal, 1 (1 - 3) Their total ileocecocolic and 3 (2 - 6) colic lymph nodes. was 0.11% of post-slaughter animal body weight corrected weight for stomach compartments weight. The MLN were immature. Wi thin twelve hours after birth and colostrum ingestion, secondary lymphoid nodules appeared on the MLN. At three months age, kids had about 38 JPP with size ranging from five follicles to patches 5.4 cm. long. The width of the JIPP was also not uniform, and it was 1.4 tn. long. There were 2 Peyer's patches were present on about 18% of the intestinal CPP. length. There were 3 (1 - 9) jejunal, 1 (1 - 2) ileocecocolic and 3 (2 - 5 ) colic lymph nodes. Their total weight was 0.29% of the post-slaughter animal body weight corrected for stomach compart- ments weight. The MLN were histologically mature. Goats of 8 - 12 months age had about 33 JPP and 2 CPP. In a single observation, three snail patches were found in the cecum. JIPP had grossly atrophied and measured about 1.5 m. in length. Peyer's patches were present on about 13% of the intestine length. There were 5 (1 - 12) jejunal, 2 (1 - 4) ileocecocolic and 4 (2 - 5 ) colic lymph nodes. Their total weight was 0.16% of the post-slaughter animal body weight corrected for stomach compartments weight. mature. The MLN were histologically There was a general trend of a decrease of IEL number on the demes and villi from cr«iiial end to caudal end of the intestinal tract. Domes epithelia were columnar and had a mean of 1.2 + 0.3, 1.8 + 0.5 and 0.2 + 0.1 goblet cells per dome in the newborn, 3 IEL nunber on months and 8-12 months old goats, respectively. dome and villi showed a general increase with age. There was no significant difference (P > 0.05) between the means of the JPP number of the three age groups.There was also no significant correlation neither betweenlength of Peyer's patches and intestine length nor between MLN and body weights. There was no significant difference ( P >0.05) between the proportion of intestine on which the Peyer's patches were present in newborn and 3 months old kids, while there was significant difference ( P < 0.05) between these two months old group. groups and the 8-12 There was significant difference (P < 0.05) between the means of the MLN weight of the three age groups and there was also significant difference (P < 0.05 ) between the means of MLN-body weight proportion of the three age groups. The JPP, JIPP and CPP had a common character of being histologically mature at birth, but differed in their follicular histology and life history. The JPP follicles were short, broad and pear-shaped, had large interfollicular areas and did not show signs of atrophy with age. The JIPP follicles were cylindrical or sac-shaped and atrophied with age like the thymus and avian Bursa of Fabricius. The atrophy of the JIPP started at the mid portion of the patch. Similarity between the caprine JIPP and the avian Bursa of Fabricius with regard to their prenatal maturation, their proximity to the gut and their postnatal involution is compatible with the assumption that the caprine JIPP is the equivalent of the avian Bursa Fabricii. A bean-shaped jejunal lymph node cdudaily located on the group chain was found in three out of seven animals. The node with the single ileocecocolic node drained the JIPP. Efferent from the bean-shaped jejunal node joined efferent of the ileoce­ cocolic lymph node and the vessel formed joined the efferent of the colic lymph nodes to form the colic trunk. In three animals, efferents of one or two colic lymph nodes drained into the ileocecocolic lymph node. The colic trunk confluenced with the jejunal trunk to form the intestinal trunk which emptied into the cisterna chyli. Goats did not have visceral trunk.
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    Effects of albizia lebbeck on haematological parameters and histological structure of digestive organs in rats
    (Sokoine University of Agriculture, 2021) Gwakisa, Aron
    In Tanzania, Albizia lebbeck is among the multipurpose plant used for treatment of various diseases and as a fodder. However, scientific information on the effects of this plant in the animal body is non-existent. Therefore, this study was conducted to evaluate the effects of methanol extracts of stem barks (SB) and leaves of Albizia lebbeck on haematological parameters and histological structure of digestive organs in rats. Sixty rats were randomly allotted into ten groups (I-X) of six rats each. Methanol extracts of SB and leaves of A. lebbeck were administered orally at doses of 100 mg/kg and 400 mg/kg to the experimental groups and the control groups received distilled water orally for five and 30 days. On days six and 31, rats were sacrificed and blood samples were collected into tripotassium ethylenediamine tetraacetate tubes for haematological analysis and tissue samples from the digestive organs (liver, stomach and jejunum) were immersion-fixed in 10% neutral buffered formalin for histopathological evaluation. Results revealed that, after five days of treatment, both extracts of A. lebbeck significantly (P<0.05) increased thrombocytes and plateletcrit at 400 mg/kg, and platelets distribution width (PDW) at 400 mg/kg SB compared to the control group. After 30 days of treatment, both extracts significantly (P<0.05) increased leucocytes at 100 mg/kg, lymphocytes and eosinophils at 400 mg/kg, also eosinophils and haematocrit at 100 mg/kg leaves, and erythrocytes at 100 mg/kg SB compared to the control group. Both extracts significantly (P<0.05) decreased mean corpuscular volume, mean platelet volume, and PDW at 100 mg/kg, monocytes at 100 mg/kg SB, and monocytes and neutrophils at 400 mg/kg leaves compared to the control group. Other haematological parameters changed insignificantly (P>0.05) at both doses and treatment durations. Histopathological lesions in the liver including empty spaces in cytoplasm of hepatocytes, sinusoids compression, necrosis, and inflammatory cells infiltration were observed for both extracts. There was no significant histopathological lesion in the stomach and jejunum at both doses and treatment durations. Therefore, prolonged use of both extracts should be discouraged because may affects haematological parameters and the liver.