An account of the different morphologies of vertebrate respiratory organs and structures. It expl... more An account of the different morphologies of vertebrate respiratory organs and structures. It explains the essence of different functional designs and strategies that have adaptively developed for the acquisition of molecular oxygen and elimination of carbon dioxide. The origins of the various respiratory systems are presented and debated from evolutionary, phylogenetic, behavioural and ecological perspectives. The book carefully outlines the interactions between the environment (the physical realm) and evolution and adaptation (the biological domain) that have set the composition and patterning of extant animal life.
Khat, an evergreen shrub habitually ingested for its euphoric and stimulatory effects, is grown m... more Khat, an evergreen shrub habitually ingested for its euphoric and stimulatory effects, is grown mainly in eastern Africa and south-western Arabia. Its consumption has, for a long time, been restricted to areas close to the sites of production but, because of recent improvement in efficiency and speed of transportation, khat consumption has spread to far flung lands such as North America, Canada, Australia, United Kingdom and parts of Europe. In regions where it is grown, daily life seems to centre on the crop bringing together farmers, traders, middle men, consumers and transporters. Thousands of dollars change hands daily in market centres where khat business is transacted making it the most lucrative business in these regions. The economies of these regions are therefore driven and sustained by khat trade. Khat contains a psychoactive compound belonging to the phenylpropylamine group of alkaloids called cathinone which has amphetamine-like effects. It causes mild euphoria, wakefulness and a host of other effects on regular consumers. Long distance truck drivers are known to constantly chew khat in order to stay awake. Some chewers, however, derive satisfaction in the ability of khat to promote work endurance while others do it for leisure. Consumers generally prefer young leaves and shoots because they contain a more potent active ingredient cathinone which decays within 48 h to a less potent form called cathine. Despite these positive attributes of khat, it poses serious health risks to consumers arising from the effects of its active ingredient, cathinoneon various organ systems. A number of studies have shown that cathinone, has serious effects on cardiovascular, oral and digestive, and urogenital systems. Some of these effects are discussed in details in this chapter.
Monitoring the condition of aquatic ecosystems is important because they provide ecological goods... more Monitoring the condition of aquatic ecosystems is important because they provide ecological goods and services on which human beings depend. The present study analyzed the physico-chemical parameters and nutrients enrichment in rivers Kisat and Auji as well as wastewater sedimentation ponds to inform appropriate management measures. The water samples were collected from eight sampling sites starting at the source running downstream and at the wastewater sedimentation ponds beginning from February to October 2021. The physico-chemical parameters were measured in situ, while nutrients were analyzed at the laboratory. The results of the study indicated inconsistencies in the variation of physico-chemical parameters and nutrients enrichment among the sampling sites. The results revealed that dissolved oxygen (DO), electrical conductivity (EC), salinity (sal), total dissolved solids (TDS), turbidity and total nitrogen (TN) showed significance difference between the sites. Similarly princ...
Journal of Veterinary Medicine and Animal Health, 2017
To determine the effects of inclusion, at different levels of Moringa oleifera leaf meal (MOLM) i... more To determine the effects of inclusion, at different levels of Moringa oleifera leaf meal (MOLM) in growing pig diets on pig’s daily feed intakes (DFI), growth performance, feed conversion efficiency (FCE), haematology and plasma lipid indices, a total 24 pigs aged 2.5 months old were selected and assigned to 4 treatment diets (T) containing: 0% (T1), 3% (T2), 6% (T3) and 12% (T4) MOLM concentrations, each with 2 replications of 3 pigs. The DFI and weekly pig weights were monitored for 7 weeks, after which 2 sets of blood samples were drawn from 2 pigs per replication for haematology and serum lipid determination. The DFI for the T4 (3.16 kg) was significantly higher than T1 (2.90 kg), T2 (2.61 kg) and T3 (2.54 kg). Pigs in T2 had significantly higher daily weight gains (0.836 kg) compared to T1 (0.807 kg), T3 (0.810 kg) and T4 (0.810 kg) groups. Furthermore, pigs in T2 and T3 had significantly higher FCE (31.57 and 31.23% respectively) compared to T4 (28.05%) and T1 (30.31%). Inclus...
Testicular morphology of long-fingered bats trapped in March and early April (a period of sexual ... more Testicular morphology of long-fingered bats trapped in March and early April (a period of sexual dormancy) was studied using both light and electron microscopy. The interstitial tissue, generally smaller in proportion to the seminiferous tubules, was largely made up of compactly arranged interstitial (Leydig) cells. Physiological cell death (apoptosis) was characterized by the occurrence of dense cytoplasm obscuring most of the subcellular organelles, myelin-like whorls of residual bodies and lipid inclusions in the cytoplasm, and roughly spheroidal nuclei. Normal mitochondria were round in outline. Some of these apoptotic cells were phagocytosed by the interstitial tissue macrophages. In the seminiferous tubules this degenerative process was marked by spermatogonial karyolysis, apoptosis of spermatocytes and extensive accumulation of large lipid droplets in the Sertoli cell cytoplasm. The tubular walls and lumen were completely devoid of spermatids and spermatozoa. These observatio...
Introduction: This study investigated short- and long-term effects of khat (Catha edulis) on hypo... more Introduction: This study investigated short- and long-term effects of khat (Catha edulis) on hypophyseal, epididymal and testicular morphology, body weight and temperature changes and haematological parameters of rabbits. Materials and Methods: Twenty five male New Zealand White rabbits, divided into five groups were used. First four groups were administered, via intra-gastric tube, 1.5, 4.5, 13.5 and 40.5 g/kg body weight respectively of khat extract thrice a week for 8 weeks while controls received normal saline. Short-term and long-term effects were evaluated for hypophyseal, epididymal and testicular morphology, body temperature as well as body weight changes, food consumption and haematological parameters. Data on haematological parameters, body weight changes, body temperature and food consumption was done using one-way ANOVA at 95% confidence interval using SPSS version 12.0. Results: There was vacuolation in spermatogonia and spermatocytes at high doses while epididymides an...
Quarterly Review of Biology - QUART REV BIOL, 2008
Preface List of Contributors 1. Fish Osmoregulation in Special Environments A.J.R. Pequeux 2. Alc... more Preface List of Contributors 1. Fish Osmoregulation in Special Environments A.J.R. Pequeux 2. Alcolapia graham: A Fish Inhabiting a Highly Alkaline Environment of Lake Magadi, Kenya Daniel W. Onyango and Seth M. Kisia 3. Cave Fishes: The Consequences of Life in Darkness Jakob Parzefall 4. Circadian Rhythms in Hypogean Fish: With Special Reference to the Cave Loach, Nemacheilus evezardi Atanu Kumar Pati 5. Hemoglobinless Antarctic Icefish: Adaptations to Living at Sub-zero Temperatures Seth M. Kisia and Daniel W. Onyango 6. Fish Life in Special Environments: Mitochondrial Function in the Cold Helga Guderley and Edouard Kraffe 7. Hypoxic Survival in Two Extremes: Under the Ice and on Coral Reefs Goran E. Nilsson and Sara Ostlund-Nilsson 8. Endocrinology of Migratory Fish Life Cycle in Special Environments: The Role of Metamorphoses Karine Rousseau and Sylvie Dufour 9. Fish Muscle Function and Pressure Philippe Sebert 10. Alepocephaloids, a Key Teleostean Group: Their Myology, Functional Anatomy, Phylogeny and Specializations to Deep-Water Environments Rui Diogo 11. Diversity and Adaptation in Deep-channel Neotropical Electric Fishes William G.R. Crampton Index Color Plate Section
An account of the different morphologies of vertebrate respiratory organs and structures. It expl... more An account of the different morphologies of vertebrate respiratory organs and structures. It explains the essence of different functional designs and strategies that have adaptively developed for the acquisition of molecular oxygen and elimination of carbon dioxide. The origins of the various respiratory systems are presented and debated from evolutionary, phylogenetic, behavioural and ecological perspectives. The book carefully outlines the interactions between the environment (the physical realm) and evolution and adaptation (the biological domain) that have set the composition and patterning of extant animal life.
Khat, an evergreen shrub habitually ingested for its euphoric and stimulatory effects, is grown m... more Khat, an evergreen shrub habitually ingested for its euphoric and stimulatory effects, is grown mainly in eastern Africa and south-western Arabia. Its consumption has, for a long time, been restricted to areas close to the sites of production but, because of recent improvement in efficiency and speed of transportation, khat consumption has spread to far flung lands such as North America, Canada, Australia, United Kingdom and parts of Europe. In regions where it is grown, daily life seems to centre on the crop bringing together farmers, traders, middle men, consumers and transporters. Thousands of dollars change hands daily in market centres where khat business is transacted making it the most lucrative business in these regions. The economies of these regions are therefore driven and sustained by khat trade. Khat contains a psychoactive compound belonging to the phenylpropylamine group of alkaloids called cathinone which has amphetamine-like effects. It causes mild euphoria, wakefulness and a host of other effects on regular consumers. Long distance truck drivers are known to constantly chew khat in order to stay awake. Some chewers, however, derive satisfaction in the ability of khat to promote work endurance while others do it for leisure. Consumers generally prefer young leaves and shoots because they contain a more potent active ingredient cathinone which decays within 48 h to a less potent form called cathine. Despite these positive attributes of khat, it poses serious health risks to consumers arising from the effects of its active ingredient, cathinoneon various organ systems. A number of studies have shown that cathinone, has serious effects on cardiovascular, oral and digestive, and urogenital systems. Some of these effects are discussed in details in this chapter.
Monitoring the condition of aquatic ecosystems is important because they provide ecological goods... more Monitoring the condition of aquatic ecosystems is important because they provide ecological goods and services on which human beings depend. The present study analyzed the physico-chemical parameters and nutrients enrichment in rivers Kisat and Auji as well as wastewater sedimentation ponds to inform appropriate management measures. The water samples were collected from eight sampling sites starting at the source running downstream and at the wastewater sedimentation ponds beginning from February to October 2021. The physico-chemical parameters were measured in situ, while nutrients were analyzed at the laboratory. The results of the study indicated inconsistencies in the variation of physico-chemical parameters and nutrients enrichment among the sampling sites. The results revealed that dissolved oxygen (DO), electrical conductivity (EC), salinity (sal), total dissolved solids (TDS), turbidity and total nitrogen (TN) showed significance difference between the sites. Similarly princ...
Journal of Veterinary Medicine and Animal Health, 2017
To determine the effects of inclusion, at different levels of Moringa oleifera leaf meal (MOLM) i... more To determine the effects of inclusion, at different levels of Moringa oleifera leaf meal (MOLM) in growing pig diets on pig’s daily feed intakes (DFI), growth performance, feed conversion efficiency (FCE), haematology and plasma lipid indices, a total 24 pigs aged 2.5 months old were selected and assigned to 4 treatment diets (T) containing: 0% (T1), 3% (T2), 6% (T3) and 12% (T4) MOLM concentrations, each with 2 replications of 3 pigs. The DFI and weekly pig weights were monitored for 7 weeks, after which 2 sets of blood samples were drawn from 2 pigs per replication for haematology and serum lipid determination. The DFI for the T4 (3.16 kg) was significantly higher than T1 (2.90 kg), T2 (2.61 kg) and T3 (2.54 kg). Pigs in T2 had significantly higher daily weight gains (0.836 kg) compared to T1 (0.807 kg), T3 (0.810 kg) and T4 (0.810 kg) groups. Furthermore, pigs in T2 and T3 had significantly higher FCE (31.57 and 31.23% respectively) compared to T4 (28.05%) and T1 (30.31%). Inclus...
Testicular morphology of long-fingered bats trapped in March and early April (a period of sexual ... more Testicular morphology of long-fingered bats trapped in March and early April (a period of sexual dormancy) was studied using both light and electron microscopy. The interstitial tissue, generally smaller in proportion to the seminiferous tubules, was largely made up of compactly arranged interstitial (Leydig) cells. Physiological cell death (apoptosis) was characterized by the occurrence of dense cytoplasm obscuring most of the subcellular organelles, myelin-like whorls of residual bodies and lipid inclusions in the cytoplasm, and roughly spheroidal nuclei. Normal mitochondria were round in outline. Some of these apoptotic cells were phagocytosed by the interstitial tissue macrophages. In the seminiferous tubules this degenerative process was marked by spermatogonial karyolysis, apoptosis of spermatocytes and extensive accumulation of large lipid droplets in the Sertoli cell cytoplasm. The tubular walls and lumen were completely devoid of spermatids and spermatozoa. These observatio...
Introduction: This study investigated short- and long-term effects of khat (Catha edulis) on hypo... more Introduction: This study investigated short- and long-term effects of khat (Catha edulis) on hypophyseal, epididymal and testicular morphology, body weight and temperature changes and haematological parameters of rabbits. Materials and Methods: Twenty five male New Zealand White rabbits, divided into five groups were used. First four groups were administered, via intra-gastric tube, 1.5, 4.5, 13.5 and 40.5 g/kg body weight respectively of khat extract thrice a week for 8 weeks while controls received normal saline. Short-term and long-term effects were evaluated for hypophyseal, epididymal and testicular morphology, body temperature as well as body weight changes, food consumption and haematological parameters. Data on haematological parameters, body weight changes, body temperature and food consumption was done using one-way ANOVA at 95% confidence interval using SPSS version 12.0. Results: There was vacuolation in spermatogonia and spermatocytes at high doses while epididymides an...
Quarterly Review of Biology - QUART REV BIOL, 2008
Preface List of Contributors 1. Fish Osmoregulation in Special Environments A.J.R. Pequeux 2. Alc... more Preface List of Contributors 1. Fish Osmoregulation in Special Environments A.J.R. Pequeux 2. Alcolapia graham: A Fish Inhabiting a Highly Alkaline Environment of Lake Magadi, Kenya Daniel W. Onyango and Seth M. Kisia 3. Cave Fishes: The Consequences of Life in Darkness Jakob Parzefall 4. Circadian Rhythms in Hypogean Fish: With Special Reference to the Cave Loach, Nemacheilus evezardi Atanu Kumar Pati 5. Hemoglobinless Antarctic Icefish: Adaptations to Living at Sub-zero Temperatures Seth M. Kisia and Daniel W. Onyango 6. Fish Life in Special Environments: Mitochondrial Function in the Cold Helga Guderley and Edouard Kraffe 7. Hypoxic Survival in Two Extremes: Under the Ice and on Coral Reefs Goran E. Nilsson and Sara Ostlund-Nilsson 8. Endocrinology of Migratory Fish Life Cycle in Special Environments: The Role of Metamorphoses Karine Rousseau and Sylvie Dufour 9. Fish Muscle Function and Pressure Philippe Sebert 10. Alepocephaloids, a Key Teleostean Group: Their Myology, Functional Anatomy, Phylogeny and Specializations to Deep-Water Environments Rui Diogo 11. Diversity and Adaptation in Deep-channel Neotropical Electric Fishes William G.R. Crampton Index Color Plate Section
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