248 A TICK-RESISTANT CONDITION IN CATTLE. 



Our examination of Mr. Hall's resistant stock : — 

 During January and February of this year (1918) one of us, 

 while enjoying the kind hospitality of Mr. and Mrs. Munro 

 Hull, carefully collected all the engorged ticks to be seen 

 on the resistant cows. The latter in most cases were 

 examined both morning and afternoon, with the exception 

 of a few non-milkers which were usuallj^ inspected only 

 oJice daily. 



The total numbers of engorged female ticks collected 

 from January- 16th to February 11th (inclusive) from the 

 following cows were : — Baby, ; Fairy, 3 ; Kittiwake, 3 ; 

 Peewee, 2 ; Primrose, ; Rainbow, 4 ; Rosie, 13 ; Sprite,, 

 ; Squib, 30 ; Sunset, 18 ; Wallum, ; Yellow, 1. Nine 

 were taken from Dot in 12 days ; and 64 from Spot (classed 

 as non-resistant) in the total period. Dot, Rosie, Spot,, 

 and Squib, are young cows ; Sunset is the least strongly 

 resistant among the older animals ; from the remaim'ng 

 nine cows only 13 fully-matured female ticks were removed 

 during 26 days. One might object that these figures were 

 evidence of the scarcity of ticks at '" Cudgeree," but such. 

 was not the case since control cattle were fairly heavily 

 infested at the same time. 



In addition to the record of our obser stations made 

 during that period we are including some made in March, 

 and June of this year (1918) and also some notes made over 

 two years ago by one of us (in June, 1916), as well as infor- 

 mation, (which we herein indicate) extracted from Mr. Hull's 

 stock book. 



Baby, born March, 1914; dam. Jessamine. An Ayrshire 

 — lUawara cross ; red roan with yellow skin. (Extensive 

 exudate was f^rst noticed in February, 1916 ; free from ticks 

 in the following month. Stock book). June 24th, 1916 : 

 clean except for presence of a few .small immature ticks ;. 

 exudate* present. 



From January 16th-31st, 1918, this cow was examined 

 daily by one of us (excejrt on 25th, 30th, and 31st), during" 

 which time no fully-matured female ticks were observed 

 though a few males and nymphs were always to be found 

 on close examination and one fair- sized female was taken 



*For an account of this exudation, see later in this paper. 



