xxviii Warble i'ly* 



"In the hot summer days ouv cows ate tormented by the 



fly, and we frequently see them galloping with tails up to get out 

 of the way of their tormentor ; this lessens the quantity of milk, 

 and prevents feeding cattle growing." — D. Byrd, Spurstow Hall, 

 Tarporley. 



All who are at all connected with management of cattle know so 

 well about the mischief caused by these wild gallops that it is not 

 necessary to give observations of these in detail, more particularly as 

 they have to be mentioned further on in the notes from contributors 

 regarding successful methods of prevention and remedy ; but all stock 

 keepers and dairy farmers know to their cost the mischief thus caused, 

 not only in delaying fattening, but danger both in the gallop itself, 

 and risk of accidents to iucalf cows, and also loss in quantity and 

 deterioration both in quality and condition of the milk. 



Loss on milk. — The only precise calculation I know of on the subject 

 is thus referred to by Prof. Riley, late Entomologist of the U. S. A. 

 Department of Agriculture : — " ' The Effect of the Warbles in the 

 Dairy ' is the title of an interesting article by T. D. Curtis, in which 

 the loss in the quantity of the flow of milk as well as its deterioration 

 in quality, resulting from the annoyance of the animals by the flies 

 while the latter are depositing eggs, and later by the grubs, is conclu- 

 sively shown, and he estimates the shrinkage at 10 per cent., and the 

 loss in quality at the same rate, making a total of 20 per cent." — See 

 ' Insect Life.' Periodical Bulletin of U. S. A. Department of Agri- 

 culture. Vol. ii., No. 5, p. 158. Washington, U. S. A., 1889. 



The following note, from personal observations by Mr. D. Byrd, 

 gives approximate estimates of loss of value on growth of feeding cattle from 

 disturbance, and on weight of cheese and percentage of milk calculably 

 lessened by the same cause : — 



" We all know to our cost how greatly these tormenting flies 

 irritate and madden the cattle, causing them to gallop or run, as if for 

 their lives, to get away from the buzz and presence of their tormentors. 

 Feeding cattle cannot grow in flesh without quiet and rest, and 

 milking cows must suffer to a greater extent than we are aware of. To 

 use a common remark, they soon ' bate ' — give less milk. To drive a 

 cow fast, or cause her to be excited, reduces the quantity and quality 

 of the milk. Without perfect quiet and rest they cannot do their best 

 for us. 



" This leads me to the one important point. What is our loss in 

 the cheese-tub caused by the Warble and Gad Fly ? I have tried to 

 estimate the loss during the four or five summer months, or even the 

 eight months that a cow is supposed to be in profit. There are certain 

 times of unrest when the cow will give about one-half of her usual 

 flow of milk. These tormeutiug flies, and the continued presence of 



