No CrossRef data available.
Published online by Cambridge University Press: 19 September 2011
A quantitative measure for assessing the level of resistance of zebu cattle to Rhipicephalas appendiculatus is discussed. Basic data for the derivation of the mathematical index were from artificial infestation of cattle to adults, nymphs and larvae ofthe Rusinga Island stock of the tick species. Observed variables were the weights and numbers of the engorged/detached instars.
The index derivation process was by the use of the stepwise discriminant function procedure and the Mahalanobis distance. These procedures led to the derivation of an index which was a function of the engorged weights of the female and nymphal instars, the numbers of detached females and the Mahalanobis distance. Variables associated with the larval instar were found to be insignificant and were therefore not included in the index function.
The derived index is capable of discriminating between susceptible and resistant cattle, and can be used to monitor changes in the resistance levels of cattle over time.
Un index mathematique base sur les resultats obtenus aprésune infestation des vaches avec le Rhipicephalus appendiculatus a été etudle. L'index est derive d'une fonction analytique discriminante qui a comme principle variables le nombre des femelles ayant pris du sang et les polds des femelles et chrysalides engorgeés. Cet index est capable de discruninér entre les vaches sucepttbles et resistantes et peut être utilises pour observer les changements du niveau de resistance chez les vaches.
To send this article to your Kindle, first ensure no-reply@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about sending to your Kindle. Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Find out more about the Kindle Personal Document Service.
To save this article to your Dropbox account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you used this feature, you will be asked to authorise Cambridge Core to connect with your Dropbox account. Find out more about saving content to Dropbox.
To save this article to your Google Drive account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you used this feature, you will be asked to authorise Cambridge Core to connect with your Google Drive account. Find out more about saving content to Google Drive.