Page 63 - The Welfare of Cattle

40 the WeLfare of CattLe

table 6.1 Cattle ectoparasites in North america and their Impacts to Cattle Production
Impact to Cattle Production a
Contact with Life Stage Food
Cattle ectoparasites Cattle on Cattle Source Damage Disturbance Disease Nuisance
Lice Permanent all blood or x
skin
scabies or “mange” Permanent all skin, lymph x
mites
new World screwworm Intermittent Immature body x
fly (Cochliomyia tissues
hominivorax)
Cattle grub Intermittent Immature body x x
(Hypoderma spp.) tissues
spinose ear tick Intermittent Immature blood x x
(Otobius megnini)
Cattle fever ticks Intermittent all blood x x
(Rhipicephalus spp.)
Pajaroello tick Intermittent all blood x x x
(Ornithodoros
coriaceus)
3-host ticks (e.g., Intermittent Mainly blood x x
Dermacentor, adult
Amblyomma ticks)
horn fly (Haematobia temporary adult blood x x
irritans)
stable fly (Stomoxys temporary adult blood x x x
calcitrans)
horse and deer flies temporary adult blood x x x x
biting midges temporary adult blood x x x
(Culicoides spp.)
black flies temporary adult blood x x
Mosquitoes temporary adult blood x x x
face fly (Musca temporary adult exudates x x
autumnalis)
house fly (Musca environmental adult exudates x x
domestica) pest
a negative impacts can be categorized as (1) physical damage to cattle caused by the feeding of ectoparasites
on blood, skin, or hair, (2) irritation and disturbance of cattle resulting in unproductive pest avoidance behaviors
in response to the painful or irritating bites of ectoparasites, (3) transmission of disease agents to cattle by
ectoparasites, and (4) nuisance to facility employees and neighbors by the activity of some ectoparasites even
when these ectoparasites have no measureable impact on cattle.

eXteNSIVe VS. INteNSIVe SYSteMS: eCtOParaSIte
PreSeNCe aND aBUNDaNCe

Cattle production systems are loosely categorized as extensive or intensive depending upon the
level of mechanization, human control over cattle nutrition, and amount of labor required for cattle
care, as described in greater complexity elsewhere in this book. Of importance to this review of
ectoparasite impacts to cattle production, extensive cattle systems are primarily pasture-based with
cattle feeding at will on a mix of pasture grasses available to them and with little to no supplemen-
tal feed, while intensive cattle systems are those where cattle are held predominantly off pasture in
dry lot pens, free stall barns, or feedlots where they receive carefully mixed feed rations balanced
to meet the production goals of the herd. From the perspective of ectoparasite impacts to cattle
operations, extensive and intensive systems differ primarily in (a) presence or absence of pasture,