• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 1
  • 1
  • Tagged with
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Aspects of the biology, behavior, bionomics, and control of immature stages of the cat flea Ctenocephalides felis felis (Bouche) (Siphonaptera: Pulicidae) in the domiciliary environment

Byron, David W. January 1987 (has links)
The larval stage of the cat flea, Ctenocephalides felis felis (Bouche), was found to exhibit behaviors that were conducive to its security in carpet. Larvae exhibited positive geotactic, and negative phototactic behaviors. This resulted in the larvae spending greater than 80% of their time at the base of the carpet pile. Cat flea larvae also exhibited a positive hydrotaxis, and appeared to exhibit undirected movements when foraging. Larva were observed to respond to disturbances by coiling their body longitudinally. Cat flea hatched and unhatched eggs, and larval exuviae were found to be dispersed in a contagious fashion within carpet. The spatial pattern of the immature stages and remains was influenced by the habits of the pet host within a given room. First-instar larvae do not move far, if at all, from the location of eclosion. The movement of the larval stage is influenced by biotic and abiotic factors in the environment. Areas of high pedestrian or pet traffic are not conducive to successful eclosion from the egg or for successful larval development. Various methods of control exist for controlling an indoor infestation including both non-chemical and chemical tactics. A method for the physical control of immature stages in carpet is vacuuming. A beater-bar vacuum removes about 50% of the eggs but less than 30% of the larvae from a carpet. Chemical control tactics indoors are normally conducted using a compressed-air sprayer. Pressure within the application system is critical for creating spray patterns which can be overlapped to allow even insecticide coverage of the substrate. A compressed-air application system is not capable of delivering pesticides in a manner that will completely penetrate the carpet substrate to reach the base of the carpet. No significant differences in carpet penetration were observed over a range of 20 to 70 psi. Regardless of pressure, more than 93% of the solution applied to carpet was deposited in the upper third (6 mm) of the carpet. Pet owners were surveyed about their knowledge and perceptions of household infestations of the cat flea, and also about financial expenditures and their willingness to pay for a flea-free environment. The importance and the pest status of flea infestations were determined to be based on physical, psychological, and economic impacts on homeowners. Respondents' perceptions of infestations on their pet were associated with infestation levels in the house. The respondents were willing to pay more for flea control in July, the onset of the flea season, than they were at the peak or decline of the season. They were also willing to pay more as their perception of the intensity of the problem on the pet or in the home increased. Household income was not shown to affect a respondent's actual financial expenditures or his willingness to pay for flea control on the pet or in the home. / Ph. D.
2

Alternative practices used by resource-limited farmers to control fleas in free-range chickens in the Eastern Cape province, South Africa

Moyo, Sipho January 2009 (has links)
Fleas are one of the major external parasites affecting free range chickens, causing irritation, tissue damage, blood loss and toxicosis which in turn affect quality and quantity of meat and egg production. There are many commercial insecticides available that are effective against fleas. These commercial insecticides have, however become expensive to most resourcelimited farmers and therefore unaffordable, causing farmers to seek low cost alternatives. This study was conducted to document, determine the existence of external parasites in freerange chickens and validate the alternative remedies used in controlling free-range chicken fleas by resource-limited farmers. A questionnaire survey was used to collect data on external parasites of free-range chickens and ethno-veterinary control remedies used by resourcelimited farmers to control these parasites at Amatola basin, in Eastern Cape, South Africa. Resource-limited farmers perceived that mites (79.6%), fleas (64.5%), lice (10.8%) and ticks (6.5%) were problematic parasites of chickens. To control these parasites, resource-limited farmers commonly use ash (28%) madubula (13% carbolic acid) (26.7%), Jeyes fluid (13% carbolic acid) (10%), paraffin (8.4%), used engine oil (2.8%), plants Tagetes minuta, Clutia pulchella, Calpurnia aurea (5.2%) and a few (4.2%) used commercial drugs Karbadust (Carbarly 5%) and mercaptothion 5%. About 7.5% of the respondents used neither of the remedies. To confirm the farmers’ perception on problematic external parasites of free-range chickens a diagnostic survey was conducted. Fifty free-range chickens were randomly selected and examined for external parasites. About 96% of the free-range chickens examined harboured at least one species of external parasites. Fleas (Echidnophaga gallinacea) (50.7%) were the most prevalent followed by lice, Menopon gallinae (12.4%); Menacanthus stramineus (5.3%) and Knemidocoptes mutans (0.57%). Given that Jeyes fluid, used engine oil, paraffin, C. aurea, C. pulchella and T. minuta were mainly used in controlling these parasites, it was important to determine the potential dermal irritant effects of these plants. A dermal irritant effect test was, therefore, conducted using a rat model. Forty eight rats, with parts of the backs shaven, were used to screen the materials for irritation. All the materials tested did not cause any visible skin irritation on rats (p>0.05). Regarding that ethnoveterinary materials were non irritant on rat skin in vitro repellency and contact bio-assay models were used to assess the insecticidal properties of Tagetes minuta, Calpurnia aurea, Clutia pulchella, used engine oil, paraffin and Jeyes fluid on fleas. For the in vitro bioassay T. minuta and Jeyes fluid at 100% concentration demonstrated a repellency level of 76 and 83%, respectively. Tagetes minuta was the most effective among plant materials (p<0.05). Clutia pulchella, C. aurea, used engine oil and paraffin showed insignificant repellency (p>0.05). For the contact bio-assay, C. pulchella, C. aurea and T. minuta at a concentration of 100% resulted in flea mortality of 83.5, 73.3 and 42.5%, respectively. The efficacy of Clutia pulchella compared well with that of Karbadust which had a mean mortality of 97.5%. Paraffin, used engine oil, and Jeyes fluid (19.2%) caused higher flea mortality of more than 82%. In the in vivo study 60 free-range chickens were artificially infested with fleas and test materials were topically applied on infested sites. Test materials exhibited varying flea load reduction efficacy. Used engine oil and Jeyes fluid at 76.8% concentration had a reduction efficacy of 100 and 96% after 3 days post application of test materials. These were not significantly different to that of the positive control Kabadust (carbaryl 5%). The plants C. pulchella and C aurea at 100% concentration had an efficacy of 92 and 77%, respectively. The commonly used remedies by resource-limited farmers to control fleas vary in efficacy. Some of the materials are as effective as the commercial insecticides hence they have a potential to be exploited as insecticides. Further investigations on plant compounds with insecticidal properties and their toxicity, need to be conducted before the plants are recommended for use.

Page generated in 0.0459 seconds