Page 240 - The Welfare of Cattle

WeLfare Issues In feedLot CattLe 217

different transport conditions. For example, the effects of environmental extremes (exposure to
ambient temperatures significantly higher or lower than the thermal neutral zone for cattle) can
be exacerbated by inadequate or excessive ventilation, as well as overloading or the presence or
absence of bedding. Excessive weight loss (>10% of body weight) associated with the mobiliza-
tion of body reserves and dehydration (Tarrant et al., 1992; Warriss et al., 1995; Knowles et al.,
1999) can result from factors such as increased energy expenditure associated with maintaining
balance for extended periods of time, limited or no ability to lie down, removal of access to feed
and water or exposure to temperature extremes. These factors are also related to negative out-
comes such as increased incidence of lameness, becoming nonambulatory or death (González
et al., 2012). Finally poor handling, driving quality, and or facilities can increase slipping and
falling which can lead to serious injury and lameness (Grandin, 1997). The most relevant find-
ings from a Canadian transportation benchmark study (González et al., 2012) indicated that more
welfare issues were observed when transportation durations exceeded 30 hours; longer journeys
at higher temperatures increased shrink and poor welfare outcomes; and cattle shipped at loading
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densities lower than 0.5 m or greater than 1.5 m were more likely to die, become nonambula-
tory, or lame on the truck. In addition, cull cows and calves were found to be more susceptible to
transport stressors as they had the highest incidence of lameness, becoming nonambulatory and
dying at the time of off-loading compared to feeder and fat cattle. Finally, poor welfare outcomes
were reduced in loads of cattle transported by drivers with more than 5 years of experience haul-
ing livestock. The authors of that study attributed this to the drivers’ heightened understanding
of the negative effects that poor driving technique (sharp cornering and stopping) has on cattle
condition as well as their ability to manage risk (i.e., minimizing delays, altering transport times
or routes during periods of inclement weather).
Currently, there are no agreed upon set of physiological or behavioral criteria (i.e., cutoffs) that
can be used to access the impacts of specific journey durations or any other conditions of transport
on cattle welfare. Although these measurements provide insight into an animal’s ability to cope
with transportation it would be difficult if not impossible to identify specific cutoffs for determin-
ing the point at which an animal’s welfare is compromised. In addition, it is unlikely that industry
stakeholders, veterinarians, or scientists would agree on where the cutoffs would lie. Consequently,
welfare evaluations during and immediately post-transport will most likely remain outcome based
using criteria such as the incidence of lameness, non-ambulation, or deaths.
Stress responses associated with long-distance transport have been shown to be reduced by the
provision of a resting period where animals can lie down and are given access to feed and water
(Cooke et al., 2013). The question still remains as to what the most appropriate rest stop length is
for long haul (>15 hours) cattle. One of the only published studies on the effects of varying rest stop
durations on cattle found that rest periods ≥10 hours did not prevent increased short- and long-term
stress (cortisol), and did not improve average daily gain measured up to 25 days after transport
(Marti et al., 2017c). The authors of this chapter caution that replication of this study is required
before definitive conclusions about rest stop length on cattle welfare can be made due to the fact that
it was not conducted using commercial transport trailers and only assessed a small number of cattle.
There is currently a lack of science-based information regarding the relationship between rest stop
duration and quality, and health and welfare outcomes in cattle once they have arrived at the feedlot.
It is important to note that the likelihood of an animal having a negative welfare outcome during
transportation relies heavily upon their fitness for transport (age and health condition at the time of
loading) in combination with how they were managed previously and the quality of handling and
driving they were exposed to (Schwartzkopf-Genswein et al., 2012b; Tucker et al., 2015). The trans-
port of compromised or unfit animals is a major welfare concern for obvious reasons. Producers
must be educated to differentiate between unfit and compromised cattle. In Canada, an unfit animal
should never be transported, while a compromised animal can be transported with special provi-
sions (CFIA, 2013).