280 A TICK-RESISTANT CONDITION IN CATTLE. 



ticks is also enjoyed by crossbreds with these native cattle. 

 Mr. Try on also quoted Dr. Nelson Mayo who stated : '• An 

 animal that has blood of the races of the East Indies named 

 China r)r Bralimin holds less ticks than does an ordinary 

 animal. This may Ijc due to the excessive acid secretion 

 of its skin, or to its short fine hair. The beast with short 

 and fine hair is less affected by ticks than the densely clothed 

 animal." Furthermore^ — ■" We liave animals that are 

 immune to ticks naturally. In a fully infested field it is 

 frequently observed that some animals are not infested,. 

 or that other animals are very lightly infested." (R.8.C,. 

 1915, ])]). 4-C and 47). Mr. Tryon suggests that what 

 characterises the Indian cattle may occur in a few of the 

 Queensland animals also, in which a little of their blood ma_v" 

 persist. 



In Algeria, experience .shewed that the buffalo and the 

 zebu (Brahmin strain) w^ere also naturally resistant to dis- 

 ease. It was found impossible to breed the buffalo with 

 domestic cattle but the zebu liy birds shared the perfect 

 immunity to fever enjoyed by the Brahmin cattle. 

 •Similar conditions were experience<l in Jamaica. (Q.A.J., 

 vol. xiii., 1903, pp. 248, 249). This is directly opposed 

 to the state of affairs existing in Ameiica where the Brahmin 

 is susceptible to fever. 



Gilruth (1912, p. 17) bears out the statements that 

 buffaloes are free from ticks. He had occasion both on the 

 mainland of the Northern Territory and on Melville Island, 

 to examine freshly killed buffaloes and also fresh hides — 

 the descendants of the Timor buffaloes, introduced in 1824 

 -1828, and also the descendants of some Indian animals 

 introduced in 1886. All were absolutely free from ticks,, 

 although grazing on country with badly-infested cattle. 

 The same author found quite different conditions to prevail 

 with the Brahmin cattle, since on the Adelaide River he 

 examined several crossbred Brahmins which he stated 

 '■ were well covered with ticks." This author has come 

 to the conclusion that the cattle tick and the tick fever 

 organism were most probably introduced with the Batavian 

 cattle brought into the Northern Territory in 1872. 



While tick-resistance in cattle in Queensland is confined 

 tj no one l)reed it may be fairly said that such resistance 



