FACULTY OF BASIC MEDICAL SCIENCES

Permanent URI for this communityhttps://repository.ui.edu.ng/handle/123456789/262

Browse

Search Results

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    A STUDY OF THE INTERACTIONS BETWEEN PLASMA CORTISOL LEVELS, ESTROUS CYCLES, RECTAL TEMPERATURES AND RESPIRATORY RATES IN HEIFERS
    (1978-06) ADEYEMO, O.
    The need to improve the animal protein diet of the Nigerian population has underlined the importation of temperate-evolved cattle into Nigeria. How these animals adapt to the new environment should be of economic and scientific interest. Under the natural hot/humid subequatorial climate of Ibadan, some physiologic, adrenocortical and reproductive functions were investigated in 6 German Brown, 5 Holstein and 6 White Fulani heifers. The Brown/ Holstein and Fulani heifers attained puberty at the average eyes, with the standard deviation, of 17.8 + 1.6, 16.7 + 1.8 and 23.7 + 1.9 months respectively. Observations on estrous cycles showed that estrous period ranged between 7 and 31 hours in the three breeds, the mean values, with the standard errors, being 16.2+0.7, 15.8 ± 0.7 and 14.6 +_0.8 hours in the Brown, Holstein and Fulani heifers respectively. The difference between the Bos taurus and Bos indices cattle was slight but significant. Most estrus commenced during the day with a greater concentration in the morning time. The intensity of estrus was high in both species though, occasionally, a few Fulani heifers showed weaker estrual signs. Average estrous cycle length was slightly longer in the Brown and Fulani than in the Holstein heifers, the values, with the standard errors, being 21.0 + 0.3, 21.4 ± 0.2 and 20.1 + 0.2 days respectively. Ovulations occurred mostly within a day after estrus, and this as well as the duration of estrus and estrous cycle length showed no seasonal variations. There was no indication that Bos taurus and Bos indicus cattle under the semi-intensive management preferred any particular season for increased sexual activity or breeding in the sub-equatorial climate. Marked shifts occurred in the respiratory rates during four selected quarters of the year. Increases occurring in the dry hot season from the values in the relatively cooler season were highly significant. Both mean morning and mean afternoon values (l4 - 44 and 17 – 75 breaths per minute respectively) were highest in the Holstein and lowest in the Fulani heifers. Rectal temperatures showed slight but significant seasonal changes. Mean values were 101.3°F (38.5°C) and 102.2°F (39.0°C) in the morning and afternoon respectively for all the heifers together through the year. The lowest afternoon values occurred in the wettest and coolest months. The Fulani and Holstein heifers showed the lowest and highest mean values respectively. Diurnal and circadian shifts in the respiratory rates and rectal temperatures in the heifers were most exaggerated in the sun and in the Holsteins, the latter particularly exhibited polypnea and hyperthermia. Unlike the zebu, the Bos taurus cattle sought shade in the sun. The Holstein heifers sought shade more frequently and stayed there longer than the Brown heifers. Basal plasma cortisol concentrations at 07 - 08.00 hours, determined by radioimmunoassay during four quarters of the year was low, ranging between 1 - 10 ng/ml with occasional mid-cycle and more frequent- . proestrual and/or estrual elevations. Mean values showed slight but significant seasonal changes. The levels in the dry season were slightly lower than in the wet season. Breed differences were not significant. Diurnal and circadian plasma cortisol concentrations in heifers in the shade and in the sun showed no rhythmical pattern. Exogenous corticotrophin at and after mid-cycle stage elicited marked and prolonged adrenocortical response which varied between heifers, and did not alter estrous. cycle rhythmicity. A high adrenal reserve in the heifers was indicated. Bos taurus cattle have been found to be adaptable to the southern Nigerian climate represented by the Ibadan condition. Management practice should, however, ensure all-year-round provision of shade and adequate nutrition including the adoption of night grazing. The Brown cattle are recommended over the Holsteins because the former are more comfortable, A mixed herd of the two breeds should be discouraged because socially the Browns dominate over the Holsteins. The Fulani cattle are more adaptable to the subequatorial climate than the temperate-evolved cattle as evidenced by the physiological responses, artificial breeding should be suitable for the Fulani cattle as it is for the Bos taurus cattle. The need to adopt better management practices than hitherto existing, range system for the Fulani cattle so that their reproductive and productive attributes may be well manifested, is indicated.
  • Thumbnail Image
    Item
    CATION CONTENT AND FLUXES IN RED CELLS OF NORMAL AND HYPERTENSIVE NIGERIANS
    (1978-08) ADEROUNMU, A. F.
    RED CELL SODIUM AND POTASSIUM CONTENT AND FLUXES IN NORMAL AND HYPERTENSIVE NIGERIANS. 1. Erythrocyte sodium, potassium and water content have been determined in 908 Nigerians so as to: 1. establish normal values in Nigerians 2. compare values in Nigerians with known values in other blacks. 3. compare values in Nigerians with those of caucasians. Red cell sodiuum, potassium and water were also determined in 7 caucasians who had been resident in Nigeria for periods varying from 6 months to 18 years. The RBC sodium for Nigerians considerably higher than those of caucasians, but the RBC potassium and water did not show any significant difference. In the course of this work, the normal (control) subjects were grouped according to their genotypes. 3 genotypes were encountered: AA, AS and AC. There was no significant difference in the erythrocyte sodium, potassium and water of the individuals belonging to these 3 genotypes. The results were also analysed for sex and age differences, and none was found. Results of erythrocyte sodium, potassium and water from 3 siblings and their mother were also presented. These results differed, from one another, suggesting that environmental factors are also important and probably just as potent determinants of RBC sodium, potassium and water content as are genetic factors. 2. 100 hypertensive subjects were studied. They were all newly diagnosed, mostly symptomless ambulant subjects who were attending the medical out-patient department of the University College Hospital, Ibadan. Their main pathological finding systemic hypertension. They were followed up for periods varying from 18 months to 3 1/2 years. Investigations were performed on each patient which enabled their being grouped into hypertensives with normal renal function or hypertensives with abnormal renal function. Only those with normal renal function were included in the study. The results obtained for the red cell sodium and potassium were significantly different from those of the Controls. Their red cell water was also significantly different from that of the Controls, but the difference m RBC water was not sufficient to account for the differences in the RBC sodium and potassium. Here again, the RBC sodium and potassium were not related to age or sex. The RBC sodium and potassium content were in no way related to the mean blood pressures. Their values remained the same both before and during treatment. Adequate control and maintenance of the patients blood pressures within the normal range did not affect these two cations. 3. When red cells from Controls and red cells from Hypertensives were exposed to a high sodium load, the RBCs from hypertensive gained a lot more sodium and lost a lot more potassium than the RBCs from Controls. 4. Normal red cells lost their potassium into isotonic sucrose media seven times as fast as red cells from hypertensive subjects. 5. Normal red cells have a slightly higher a tive sodium flux per hour than red cells from hypertensive subjects, but the difference is not statistically significant. The rate constant for active sodium flux is higher for red cells of Controls than for red cells of hypertensive subjects, but the correlation between intracellular sodium content and rate constant is not good (r= -0.43). The rate constant for the red cells of the hypertensives is lower, but it correlates better with the red cell sodium (r =0.53).
  • Thumbnail Image
    Item
    IMMUNOPATHOLOGY OF AMOEBIASIS IN IBADAN
    (1971) ABIOYE, A. A.
    Amoebiasis exemplifies a disease of protean manifestations which presents many perplexing problems. In this thesis an attempt is made to define a number of the wide variations which have been observed in the pathological manifestations of the disease. The work consists of both retrospective and prospective Studies. The retrospective study involved a review of the 7922 protocols of the autopsies at the University College Hospital, Ibadan, during the ten year period 1958 to 1967. 135 cases in which lesions of amoebiasis were described, were selected for special study using 276 cases of other diarrhoeal diseases as controls. The results of this review defined the pathology and complications of amoebiasis seen at the UCH, during the period covered by this study. A prospective study which included field surveys. laboratory studies on patients and controls; and in-vitro studies of the parasite was also carried out. Parasitological, biochemical and immunological techniques were applied in the prospective study of 1291 subjects in a field survey. In addition some 200 hospital materials were included in the prospective study. The results obtained provided the basis for the suggestions made concerning the different methods that can be applied to the future study of the prevalence of amoebiasis in any given population exposed to the risk of infection by Entamoeba histolytica. Local (Ibadan) strains of Entamoeba histolytica have been successfully cultured and the in-vitro characteristics studied. From the materials provi.ded by the in-vitro cultures of the organism, investigations have been made on E. histolytica antigens and the corresponding antibodies produced in man. The results of these investigations have been utilized in immunological studies, designed to define the mechanism of production of some of the problems posed by amoebic infections. The severity and high fatality of the disease in pregnancy and puerperium, was studied in detail. The observation that amoebiasis tends to be more severe and to have a higher mortality in pregnant and puerperal women was made only recently. At the time the present studies were planned, the association of pregnancy with severe amoebiasis had not been well established, and the mechanism for this association was unknown. It was, however, wall known that pregnant women were more liable to severe for-ms of certain other infectious diseases and it was considered possible that a similar mechanism might be operating in the case of amoebiasis. The present work confirms these clinical observations. Thus from the statistical analyses of the results of both the autopsy and prevalence studies, it became evident that the high fatality of amoebiasis during pregnancy and the early puerperium was not fortuitous but real. A fulminating type of lesion affecting the whole length of the large bowel is commoner in pregnant women and in those in the early puerperium dying of amoebiasis, than in any other cases of amoebiasis seen at autopsy. Furthermore, the biochemical and immunological studies help to throw some light on the mechanism of the selectivity of Infection by E. histolytical. These same results, also provide some explanation for the severity of amoebiasis during pregnancy and the allied states. The conclusions, support the hypothesis of lowered resistance to infectious diseases during pregnancy. Speculative submissions are, therefore, made on the defective immune mechanism occurring during pregnancy and the early puerperium. Thus, the inability of pregnant women to produce 'sufficient antibodies' to amoebic infections, demonstrated by the reactivity of the immunoglobulins in amoebiasis, confirms the suspicion of the existence of a derangement of host-defence mechanisms during pregnancy. This raises the hope and encourages future search for the specific serum agents) which may account for the deranged immune mechanism. On similar basis, the characterization of amoebic antigens together with that of the corresponding antibodies, offers a new field in the study of the immunopathology of amoebiasis. In conclusion, from the combined autopsy, prevalence, in-vitro experimental, biochemical, and immunological studies, it is submitted: 1. That the association of pregnancy with the severe form of amoebiasis at least, in this part of the world, is one of the perplexing problems posed by the disease. 2. That chronic amoebic infection is associated with the development of growth-inhibiting factors in the serum, for example, in patients with amoebic liver abscess. 3. That, on the contrary, growth promoting factors were demonstrated in the sera of pregnant/puerperal women with or without acute amoebic dysentery. 4. It is suggested that the severity of the disease in pregnant/puerperal women is a reflection of the derangement of immune response during pregnancy, with particular reference to the production of serum immunoglobulins.