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Articles 2371 - 2400 of 2421

Full-Text Articles in Life Sciences

Disruption Of Glossina Morsitans Morsitans (Diptera: Glossinidae) Eclosion Behaviour: A Novel Method For Evaluating The Action Of Neurotoxic Agents, J. Ždárek, D. L. Denlinger Jan 1992

Disruption Of Glossina Morsitans Morsitans (Diptera: Glossinidae) Eclosion Behaviour: A Novel Method For Evaluating The Action Of Neurotoxic Agents, J. Ždárek, D. L. Denlinger

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As the tsetse fly, Glossina morsitans morsitans Westwood extricates itself from the puparium and moves upward through the soil the ptilinum expands and contracts rhythmically and thus generates a stereotypic behavioural pattern that persists for up to 10 h if the tsetse fly remains confined. The response, which is easily recorded tensometrically from the movements of the ptilinum, can be exploited as a tool for evaluating the behavioral response of tsetse flies to various neurotoxic agents. The behavioural assay proves useful in providing precise information about the latency of the response and lethal time, and can suggest likely modes of …

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Trypanosome Infection Rates In Tsetse Flies (Diptera: Glossinidae) And Cattle During Tsetse Control Operations In The Kagera River Region Of Rwanda, Steve Mihok, Leonard H. Otieno, Christopher S. Tarimo Jan 1992

Trypanosome Infection Rates In Tsetse Flies (Diptera: Glossinidae) And Cattle During Tsetse Control Operations In The Kagera River Region Of Rwanda, Steve Mihok, Leonard H. Otieno, Christopher S. Tarimo

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Trypanosome infections were monitored in three species of tsetse fly (Glossina pallidipes Austen, G. morsitans centralis Machado, and G. brevipalpis News-tead) at four locations in the Kagera River region of Rwanda from May 1989 to September 1990. Two of the four areas (Mpanga Ranch and Bukora Ranch) were subjected to tsetse fly suppression operations with odour-baited traps. Proboscis infections of the Trypanosoma congolense and T. vivax types accounted for roughly equal numbers of the 207 mature infections detected (3.8%). Variation in infection rates was area-specific rather than tsetse species-specific. Order of magnitude differences in tsetse fly densities among areas were …

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Studies On Tsetse Midgut Factors That Induce Differentiation Of Bloodstream Trypanosoma Brucei Brucei In Vitro, M. O. Imbuga, E. O. Osir, V. L. Labongo, N. Darji, L. H. Otieno Jan 1992

Studies On Tsetse Midgut Factors That Induce Differentiation Of Bloodstream Trypanosoma Brucei Brucei In Vitro, M. O. Imbuga, E. O. Osir, V. L. Labongo, N. Darji, L. H. Otieno

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An in vitro system for studying the transformation of bloodstream forms of Trypanosoma brucei brucei into procylic (midgut) forms is described. In this system, transformation of the parasites was stimulated by Glossina morsitans morsitans midgut homogenates at 27° C but not at 4° C. The transformation-stimulating capacity was irreversibly destroyed by heating the midgut homogenates at 60° C for 1 h. A correlation was established between the transformation activity of the midgut homogenates and trypsin activity. The protease inhibitors (soybean trypsin inhibitor and N-p-tosyl-l-lysine-chloromethyl-ketone) inhibited trypsin activity and completely blocked the transformation of the parasites. Furthermore, the midgut homogenates could …

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Influence Of D(+)-Glucosamine On Infection Rates And Parasite Loads In Tsetse Flies (Glossina Spp.) Infected With Trypanosoma Brucei, Steve Mihok, Leonard H. Otieno, Nafisa Darji, David Munyinyi Jan 1992

Influence Of D(+)-Glucosamine On Infection Rates And Parasite Loads In Tsetse Flies (Glossina Spp.) Infected With Trypanosoma Brucei, Steve Mihok, Leonard H. Otieno, Nafisa Darji, David Munyinyi

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Teneral Glossina morsitans centralis, G. m. morsitans and G. pallidipes were infected with three different clones of Trypanosoma brucei in blood containing d(+)-glucosamine, an inhibitor of tsetse midgut lectin. On average, 5 days of d(+)-glucosamine treatment tripled infection rates, without affecting the proportion of infections that matured. Total infection rates were equal in males and females, but twice as many infections matured in males. Counts of parasites in the guts and salivary glands of 277 flies revealed order of magnitude differences among flies, with females consistently having 2-3-times as many parasites as males. Parasite numbers varied in a sex-specific manner …

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Immunization Of Cattle With A Semi-Purified Fraction Of Solubilized Membrane-Bound Antigens Extracted From The Midgut Of The Tick Rhipicephalus Appendiculatus, Suliman Essuman, Olusegun O. Dipeolu, Thomas R. Odhiambo Nov 1991

Immunization Of Cattle With A Semi-Purified Fraction Of Solubilized Membrane-Bound Antigens Extracted From The Midgut Of The Tick Rhipicephalus Appendiculatus, Suliman Essuman, Olusegun O. Dipeolu, Thomas R. Odhiambo

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Boran cattle were immunized with a semi-purified fraction (F2) of solubilized membrane-bound antigens extracted from the midgut of the tick Rhipicephalus appendiculatus. A subsequent challenge with all stages of R. appendiculatus showed protection of the cattle to a significant degree. There was a decrease in engorgement weight of ticks, the number which fed above critical engorgement weight was considerably reduced, and about 38% of the larvae which fed to repletion did not moult. The major cause of death of adult female ticks was the increased grooming by cattle as a result of increased dermal irritation. © 1991 Elsevier Science Publishers …

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Towards The Selection Of Cattle For Tick Resistance In Africa, J. J. De Castro, P. B. Capstick, S. Nokoe, H. Kiara, F. Rinkanya, R. Slade, O. Okello, L. Bennun Oct 1991

Towards The Selection Of Cattle For Tick Resistance In Africa, J. J. De Castro, P. B. Capstick, S. Nokoe, H. Kiara, F. Rinkanya, R. Slade, O. Okello, L. Bennun

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Half-body tick collections and visual assessment of tick burdens were performed monthly over six months on 100 bulls at the Kenya National Boran Stud, Mutara Ranch, Kenya. Boophilus decoloratus predominated among several tick species infesting the animals. Burdens of B. decoloratus and total tick burdens were highly correlated. Rankings of relative tick resistance among bulls were consistent from month to month. Rankings based on visual assessment were very close to those based on actual tick burdens. Animals with thin skins appeared to carry fewer ticks, but tick burden bore no relationship to coat colour. The results suggest that simple visual …

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Bionomics Of Tetrastichus Sesamiae [Hymenoptera: Eulophidae], A Pupal Endo-Parasitoid Of Maruca Testulalis [Lepidoptera: Pyralidae], J. B. Okeyo-Owuor, G. W. Oloo, P. O. Agwaro Sep 1991

Bionomics Of Tetrastichus Sesamiae [Hymenoptera: Eulophidae], A Pupal Endo-Parasitoid Of Maruca Testulalis [Lepidoptera: Pyralidae], J. B. Okeyo-Owuor, G. W. Oloo, P. O. Agwaro

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The biology and behaviour of Tetrastichus sesamiae Risbec, a pupal endoparasitoid of Maruca testulalis Geyer, were studied under laboratory conditions. Most adults emerged from the host pupae between 08.00 h and 09.00 h and mating and oviposition started almost immediately. Both ♂♂ and ♀♀ mated repeatedly, and each ♀ could lay eggs for up to 6 days and in up to 5 host pupae. Progeny production ranged from 0-263 offspring per ♀ and adult longevity was from 4.3-13.9 days. The quality of food available to the adults was a major factor influencing progeny production, and longevity. The species was capable …

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Turnover In The Populations Within Mature Nests Of The Termite Macrotermes Michaelseni In Kenya, J. P.E.C. Darlington Sep 1991

Turnover In The Populations Within Mature Nests Of The Termite Macrotermes Michaelseni In Kenya, J. P.E.C. Darlington

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Production in mature termite nests consists of a seasonal brood of reproductives and a continuous turnover of steriles. The sterile population of the nest remained fairly constant, with no regular seasonal fluctuations. Growth rates of steriles were estimated by interrupting the input and following the "missing cohort". Estimated mean values of standing crop biomass and annual production in a mature nest were used to calculate a production-to-biomass ratio. In conjunction with data on the density of nests in the field, the biomass and production per hectare were estimated. © 1991 Birkhäuser Verlag.

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Response [3], Stephen J. O'Brien, Ernst Mayr Jan 1991

Response [3], Stephen J. O'Brien, Ernst Mayr

Biology Faculty Articles

No abstract provided.

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Electrophoretic Study Of Enzymes From A Glossina Fuscipes Fuscipes Newstead Population From Western Kenya, G. F. Rajendram Jan 1991

Electrophoretic Study Of Enzymes From A Glossina Fuscipes Fuscipes Newstead Population From Western Kenya, G. F. Rajendram

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Enzymes were investigated, by electrophoresis, in a population of Glossina fuscipes fuscipes Newstead collected from Rusinga Island in Lake Victoria, Western Kenya. The following enzymes were tested: glucose phosphate isomerase. glucose-6-phosphate dehydrogenase (G6PDH). hexokinase, isocitrate dehydrogenase (IDH), malate-dehydrogenase (MDH), phosphoglucomutase, and xanthine dehydrogenase (XDH). Single monomorphic bands were stained by the following enzymes apparently under the control of single loci: G6PDIL MDH, and XDH. The enzyme IDH showed two bands with very close mobilities and no variation among individuals in the population. Hence IDH was considered as representing a single locus. Glucose phosphate isomerase manifested three alleles and apparently six …

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Enhancement Of Diapause Development In A Stem Borer, Busseola Fusca (Lep.: Noctuidae) By Dry Conditions, Takashi Okuda Jan 1991

Enhancement Of Diapause Development In A Stem Borer, Busseola Fusca (Lep.: Noctuidae) By Dry Conditions, Takashi Okuda

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Water was an important factor for diapause termination only during the late stage of the diapause in Busseola fusca. Exposure to dry conditions for 2 months accelerated diapause development more. Diapause development proceeded at warm temperatures only. © 1991, JAPANESE SOCIETY OF APPLIED ENTOMOLOGY AND ZOOLOGY. All rights reserved.

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Trap-Catches, Nutritional Condition And The Timing Of Activity Of The Tsetse Fly Glossina Longipennis (Diptera: Glossinidae), Sarah E. Randolph, D. J. Rogers, R. D. Dransfield, R. Brightwell Jan 1991

Trap-Catches, Nutritional Condition And The Timing Of Activity Of The Tsetse Fly Glossina Longipennis (Diptera: Glossinidae), Sarah E. Randolph, D. J. Rogers, R. D. Dransfield, R. Brightwell

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Samples of Glossina longipennis Corti, taken over four days in traps (baited with acetone, cow urine and octenol) at half-hourly intervals during their restricted activity periods at dusk and dawn, were analysed for their nutritional condition. For both sexes, trap catches were highest at the end of dusk, between 19.00 and 19.30 h, associated with a significant increase in numbers with the low haematin content characteristic of flies estimated to have fed more than 60 hours previously. Also, the mean fat content of these flies was significantly lower than that of those trapped earlier. There was considerable day-to-day variation in …

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Infection Rates In Glossina Morsitans Morsitans Fed On Waterbuck And Boran Cattle Infected With Trypanosoma Congolense, Steve Mihok, Reardon O. Olubayo, David F. Wesonga Jan 1991

Infection Rates In Glossina Morsitans Morsitans Fed On Waterbuck And Boran Cattle Infected With Trypanosoma Congolense, Steve Mihok, Reardon O. Olubayo, David F. Wesonga

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Teneral Glossina morsitans morsitans were fed on waterbuck (Kobus defassa) and Boran cattle (Bos indicus) infected experimentally with Trypanosoma congolense clone IL2895. Infection rates in tsetse varied from 9 to 31% when fed on cattle, and from 2 to 59% when fed on waterbuck. In waterbuck, infections were often detected through the development of parasites in tsetse at times when parasitaemia could not be detected through microscopic examination of blood. Male and female, and 1- and 2-day-old flies were equally susceptible to infection on both hosts. Infection in tsetse was associated with a 14% absolute reduction in survival during the …

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Predation On Livestock Ticks By Chickens, S. M. Hassan, O. O. Dipeolu, A. O. Amoo, T. R. Odhiambo Jan 1991

Predation On Livestock Ticks By Chickens, S. M. Hassan, O. O. Dipeolu, A. O. Amoo, T. R. Odhiambo

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Chickens were shown to be natural predators of ticks. Rhipicephalus appendiculatus were recovered in large numbers from the crops and gizzards of chickens which had scavenged for 30 min-1 h among tick-infested cattle. Other ticks recovered were Amblyomma variegatum and Boophilus decoloratus. The numbers of ticks recovered ranged from 3 to 331, with an average of 81 per chicken. Cattle facilitated the predation of ticks by certain behavioural actions. Chickens also picked up both engorged and unengorged ticks seeded on vegetation, but unengorged ticks were preferred. The possibility of tick predation by chickens forming a viable biological control component in …

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Juvenile Hormone Binding To A 500-K Diapause-Associated Protein Of The Stem-Borer, Busseola Fusca, Ellie O. Osir, Gopalan C. Unnithan, Glenn D. Prestwich Jan 1991

Juvenile Hormone Binding To A 500-K Diapause-Associated Protein Of The Stem-Borer, Busseola Fusca, Ellie O. Osir, Gopalan C. Unnithan, Glenn D. Prestwich

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1. 1. The larval haemolymph of the stem-borer, Busseola fusca Fuller (Lepidoptera: Noctuidae) contains a high molecular weight protein (Mr ∼ 500,000) that is induced only during diapause. This diapause-induced protein, termed Busseola diapause protein (BDP), has been previously isolated and characterized. 2. 2. In this study, BDP has been shown to be a specific juvenile hormone (JH) binder by labelling with epoxybisfarnesyl diazoacetate (EBDA), the photoactivatable analog of JH I (10R, 11S). 3. 3. In a direct binding assay, BDP was also shown to bind [3H]-JH I (10R, 11S) with high affinity (Kd ∼ 120 nM). 4. 4. These …

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Feeding Responses Of Chilo Partellus (Swinhoe) (Lepidoptera: Pyralidae) Larvae To Sorghum Plant Phenolics And Their Analogs, Baldwyn Torto, Ahmed Hassanali, Kailash N. Saxena, Sagary Nokoe Jan 1991

Feeding Responses Of Chilo Partellus (Swinhoe) (Lepidoptera: Pyralidae) Larvae To Sorghum Plant Phenolics And Their Analogs, Baldwyn Torto, Ahmed Hassanali, Kailash N. Saxena, Sagary Nokoe

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Phagostimulatory responses of third-instar larvae of Chilo Partellus to phenolic components identified in an ethyl acetate extract of the leaf whorls of 3-week-old plants of Sorghum bicolor cultivar IS 18363 were studied in no-choice bioassays. The major components in the extract were identified as 4-hydroxybenzaldehyde and 4-hydroxybenzoic acid, with 4-hydroxy-3-methoxycinnamic acid, 3,4-dihydroxycinnamic acid, and 4-hydroxycinnamic acid present in minor amounts. All but 4-hydroxycinnamic acid were stimulatory at the doses tested. 4-Hydroxybenzaldehyde was more stimulatory than other potential biogenetic analogs. Hydroxybenzoic acids generally elicited greater feeding response than cinnamic acids, and the pattern of oxygen substitution in the benzene ring was …

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Commitment To Metamorphosis In Tsetse (Glossina Morsitans Centralis): Temporal, Nutritional And Hormonal Aspects Of The Decision, David L. Denlinger, Jan Žďárek Jan 1991

Commitment To Metamorphosis In Tsetse (Glossina Morsitans Centralis): Temporal, Nutritional And Hormonal Aspects Of The Decision, David L. Denlinger, Jan Žďárek

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Larvae of Glossina morsitans centralis were manually extruded from the uterus of the female at different times during the third (final) larval instar to evalute their competence to initiate metamorphosis. Parturition is a gated response in tsetse, and in this species the peak of activity occurred 8.7 h after the onset of the daily 12 h photophase. Larvae aborted a few hours prematurely were completely competent to crawl and pupariated within 1-2 h, but a portion of the puparia blackened before tanning. Younger larvae (22.9 mg vs full grown weight of 33.6 mg) were also competent to crawl, but after …

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Monitoring Secondary Outbreaks Of The African Armyworm In Kenya Using Pheromone Traps For Timing Of Bacillus Thuringiensis Application, M. Broza, M. Brownbridge, B. Sneh Jan 1991

Monitoring Secondary Outbreaks Of The African Armyworm In Kenya Using Pheromone Traps For Timing Of Bacillus Thuringiensis Application, M. Broza, M. Brownbridge, B. Sneh

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The arrival of male moths of the African armyworm, Spodoptera exempta Walker, was monitored in Kenya using pheromone traps. Peak trap counts were obtained during March 1989, and were concentrated in three out of nine traps distributed in small farms in an area of 625 km2 in Lambwe valley, South Nyanza. Large numbers of egg masses were located on dry stalks of last year's cereals in wild cynodon grass situated around the crop fields. Smaller numbers were found on the underside of the first emerged leaves of maize seedlings. Few egg masses were found on millet crops. Application of a …

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Pathogenicity Of Tsetse-Transmitted Trypanosoma Congolense For Waterbuck (Kobus Defassa) And Boran Cattle (Bos Indicus), R. O. Olubayo, S. Mihok, D. F. Wesonga, E. R.M. Mbwabi Jan 1991

Pathogenicity Of Tsetse-Transmitted Trypanosoma Congolense For Waterbuck (Kobus Defassa) And Boran Cattle (Bos Indicus), R. O. Olubayo, S. Mihok, D. F. Wesonga, E. R.M. Mbwabi

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Five waterbuck (Kobus defassa) and four Boran cattle (Bos indicus) were infected with Trypanosoma congolense IL2895 using Glossina morsitans morsitans. At the same time, two waterbuck and two cattle were inoculated intravenously with bloodstream forms. With both methods of challenge, cattle had short prepatent periods followed by a continuous high parasitaemia. All cattle became severely anaemic and had to be treated with trypanocidal drugs to prevent death. In contrast, tsetse and intravenous challenge of waterbuck resulted in a long prepatent period, followed by brief, intermittent levels of low parasitaemia, and eventual selfcure. Waterbuck did not become anaemic, even during short …

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Pheromonal Trapping Of Chilo Partellus (Swinhoe) (Lepidoptera: Pyralidae) Moths In Relation To Male Population Density And Competition With Females, Gopalan Chandran Unnithan, Kailash Narain Saxena Jan 1991

Pheromonal Trapping Of Chilo Partellus (Swinhoe) (Lepidoptera: Pyralidae) Moths In Relation To Male Population Density And Competition With Females, Gopalan Chandran Unnithan, Kailash Narain Saxena

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The numbers of laboratory-reared males of Chilo partellus (SWINHOE) which were released, both in a screenhouse and in the field, and recaptured in virgin female-baited traps were positively correlated. Pheromone trap catches were reduced by 75–100% when 18 or 36 virgin females were placed in two concentric circles of radii 10 m and 20 m occupying an area of 1,257 sq m. around the trap. Mated females surrounding the trap did not cause a significant decrease in the trap catch. Tethered virigin females surrounding a virgin female-baited trap competed successfully among themselves and with the trap for receptive males, the …

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Host Plant Selection By Helicoverpa Armigera (Lepidoptera: Noctuidae): The Role Of Some Herbivore Attributes, S. Firempong, M. P. Zalucki Jan 1991

Host Plant Selection By Helicoverpa Armigera (Lepidoptera: Noctuidae): The Role Of Some Herbivore Attributes, S. Firempong, M. P. Zalucki

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The effect of various ‘herbivore’ attributes on oviposition in Helicoverpa armigera were considered in a series of laboratory experiments. Larval diet did not influence the rank order of adult host preference, but early adult experience around a host increased oviposition on that host in subsequent trials. The presence of eggs laid 12 h before did not influence subsequent oviposition on a plant, although newly laid eggs may have. The presence of larvae, larval damage to plants and larval frass reduced oviposition on a plant. These results are discussed in relation to polyphagy in H. armigera. © 1991, CSIRO. All rights …

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Mechanisms Of Resistance In Wild Rice Oryza Brachyantha To Rice Leaffolder Cnaphalocrocis Medinalis (Guenée) (Lepidoptera: Pyralidae), R. Ramachandran, Z. R. Khan Jan 1991

Mechanisms Of Resistance In Wild Rice Oryza Brachyantha To Rice Leaffolder Cnaphalocrocis Medinalis (Guenée) (Lepidoptera: Pyralidae), R. Ramachandran, Z. R. Khan

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A wild rice, Oryza brachyantha, was rated as highly resistant to rice leaffolder, Cnaphalocrocis medinalis (Guenée), while its F1 hybrid from a cross with a high-yielding, leaffolder-susceptible rice, IR31917-45-3-2, was rated resistant in a standard screening test. In comparison with IR31917-45-3-2, O. brachyantha and the F1 hybrid were unsuitable for oviposition, survival, and growth of C. medinalis. However, growth and survival of larvae in artificial diets containing lyophilized leaf powder of IR31917-45-3-2 and O. brachyantha were comparable. Studies on the feeding and settling preference of the larval stages suggested that the mechanism of resistance of O. brachyantha is that of …

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Volatile Components Of Banana Pseudostem Of A Cultivar Susceptible To The Banana Weevil, Isaiah O. Ndiege, William J. Budenberg, Wilber Lwande, Ahmed Hassanali Jan 1991

Volatile Components Of Banana Pseudostem Of A Cultivar Susceptible To The Banana Weevil, Isaiah O. Ndiege, William J. Budenberg, Wilber Lwande, Ahmed Hassanali

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Volatiles from banana ('githumo''cultivar) pseudostem were trapped using porapak S. The trapped volatiles were desorbed from porapak columns by elution with dichloromethane and analysed using GC and GC-MS. The volatile compounds identified included α-pinene, β-pinene, β-myrcene, limonene, α-cubebene, α-copaene, α-cedrene, β-caryophyllene and α-humulene. © 1992.

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Leishmaniasis In A Domestic Goat In Kenya, A. Olufemi Williams, J. Mutinga, M. Rodgers Jan 1991

Leishmaniasis In A Domestic Goat In Kenya, A. Olufemi Williams, J. Mutinga, M. Rodgers

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The pathological and electron-microscopic features of the first case of autochthonous leishmaniasis affecting a domestic goat in Kenya are described. They are similar to what have been described in man and other animals. Using a short amino-acid sequence common to all the species of leishmania as primers for kDNA synthesis, the intervening sequence of 120 bases was amplified in the goat's tissues by polymerase chain reaction (PCR). The leishmania kinetoplast DNA sequence was detected in all the different infected tissues of the goat examined. The sensitivity and specificity of this assay are discussed. The result of the assay used was …

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Histopathology Of Attachment Sites Of Amblyomma Variegatum And Rhipicephalus Appendiculatus On Zebu Cattle Of Varying Resistance To Ticks, A. A. Latif, D. K. Punyua, P. B. Capstick, S. Nokoe, A. R. Walker, J. D. Fletcher Jan 1991

Histopathology Of Attachment Sites Of Amblyomma Variegatum And Rhipicephalus Appendiculatus On Zebu Cattle Of Varying Resistance To Ticks, A. A. Latif, D. K. Punyua, P. B. Capstick, S. Nokoe, A. R. Walker, J. D. Fletcher

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Mature, unimproved East African Zebu cattle (Bos indicus) naturally exposed to ticks from birth were ranked for resistance to ticks by repeated whole-body counts of infesting ticks. Four cattle of high resistance, four of low resistance and two of intermediate resistance were artificially infested with nymphs of Amblyomma variegatum and Rhipicephalus appendiculatus. Two Friesian cattle (Bos taurus) with less exposure to ticks were similarly infested. Biopsies of tick attachment sites were examined histologically. All attachment sites showed acute inflammatory lesions, and sites of both tick species on high resistance cattle showed delayed hypersensitive reactions with intra-epidermal pustulation and significant increases …

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Lipophorin From The Tsetse Fly, Glossina Morsitans Morsitans, James O. Ochanda, Ellie O. Osir, Edward K. Nguu, Norah K. Olembo Jan 1991

Lipophorin From The Tsetse Fly, Glossina Morsitans Morsitans, James O. Ochanda, Ellie O. Osir, Edward K. Nguu, Norah K. Olembo

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1. 1. Lipophorin was isolated from the haemolymph of adult tsetse fly, Glossina morsitans morsitans, by ultracentrifugation in a potassium bromide density gradient. 2. 2. The tsetse fly lipophorin (Mr {reversed tilde equals} 600,000) has a density of {reversed tilde equals} 1.11 g/ml and consists of two apoproteins, apolipophorin-I (apoLp-I, Mr {reversed tilde equals} 250,000) and apolipophorin-II (apoLp-II, Mr {reversed tilde equals} 80,000), both of which are glycosylated as shown by staining with periodate-Schiff reagent. The protein complex is composed of 49% protein and 51% lipids. 3. 3. The finding of lipophorin in tsetse fly haemolymph suggests that, although these …

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Structural Studies On The Major Milk Gland Protein Of The Tsetse Fly, Glossina Morsitans Morsitans, Ellie O. Osir, Michael Kotengo, Mohammed F.B. Chaudhury, Leonard H. Otieno Jan 1991

Structural Studies On The Major Milk Gland Protein Of The Tsetse Fly, Glossina Morsitans Morsitans, Ellie O. Osir, Michael Kotengo, Mohammed F.B. Chaudhury, Leonard H. Otieno

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1. 1. The major protein in the milk gland secretions of the tsetse fly, Glossina morsitans morsitans, was isolated by a combination of gel permeation chromatography and crystallization. 2. 2. It has a native Mr ∼47,000 and is composed of two identical polypeptide chains (Mr ∼21,000) as determined by chemical cross-linking studies. The protein has no covalently-bound carbohydrates or lipids. Amino acid analysis of the protein revealed relatively high amounts of the aromatic amino acids, tyrosine (9.1 mol.%) and phenylalanine (8.5 mol.%). Immunoblotting experiments using antiserum against the protein revealed no cross-reactivity with any other milk proteins. 3. 3. Quantitation …

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Screening For Highly Effective Isolates Of Bacillus Thuringiensis Against Spodoptera Exempta And Spodoptera Littoralis, M. Hamal, M. Brownbridge, M. Broza, B. Sneh Jan 1991

Screening For Highly Effective Isolates Of Bacillus Thuringiensis Against Spodoptera Exempta And Spodoptera Littoralis, M. Hamal, M. Brownbridge, M. Broza, B. Sneh

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Several new isolates of Bacillus thuringiensis Berliner have shown significantly higher levels of insecticidal activity than the previous best isolates (Bt24- entomocidus and IH-A- aizawai) against both Spodoptera littoralis Boisd. and Spodoptera exempta Walker. The best ones, in the following descending order of potency, were: against S. littoralis — K26–21, MF4B–2, MR1–37, K28–30, K26–8; against S. exempta — Bt-3, K30–3, HD-133, MR1–37, Bt-17, K26–8, K26–21, MF4B-2, HD-593. Larvae of S. exempta were considerably more susceptible (4.12–1.25 fold) to some of the isolates (Bt-3, K30–3, HD-133, MR1–37, Bt-17, K26–8, HD-593) than S. littoralis. © 1991, Springer Science + Business Media B.V.. …

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Cattle Management, Norris Stenquist, James A. Bennett, Deevon Bailey, University Extension Sep 1989

Cattle Management, Norris Stenquist, James A. Bennett, Deevon Bailey, University Extension

University Extension - OCW

"Managing Cattle Under Drought Conditions" Ednet Teleconference

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In Vitro Maturation And Fertilization Of Domestic Cat Follicular Oocytes, L. A. Johnston, S. J. O'Brien, D. E. Wildt Jan 1989

In Vitro Maturation And Fertilization Of Domestic Cat Follicular Oocytes, L. A. Johnston, S. J. O'Brien, D. E. Wildt

Biology Faculty Articles

No abstract provided.

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