Page 285 - The Welfare of Cattle

262 the WeLfare of CattLe

the cow, with the reported incidence of production-related diseases dramatically increasing over
the past few decades. Despite evidence that onset of reproduction at earlier ages is correlated with
reduced longevity, the dairy industry has pushed to lower the age at first calving for economic
reasons (Knaus, 2009). The tremendous increase in cow production along with early first calving
age now manifests in metabolic disorders, foot and leg problems, and fertility issues, all of which
contribute to reduced longevity (Oltenacu and Broom, 2010).
Lameness and mastitis have become particularly troublesome issues, routinely ranking at the
top of the most serious and costly welfare problems in dairy production (Ventura et al., 2015). In
a review of the welfare impacts of lameness in dairy cows, Whay and Shearer (2017) noted that a
study conducted in Minnesota of 50 cow herds revealed that 15% of the cows were clinically lame
(lameness score ≥3) and 2.5% were severely lame. However, detection of lameness, particularly
early in its development, remains a challenge for herd managers who underreport it compared to
trained evaluators (Espejo et al., 2006; von Keyserlingk et al., 2009). Lameness reduces cow com-
fort; in more advanced cases, the pain and suffering associated with failure to detect and treat the
condition in cows presents even greater challenges to cow welfare, while also increasing costs for
farmers who are subsequently forced to cull animals whose productivity is compromised.
Here, considerations of permitting cows to live according to their telos or natures become rel-
evant, as existing science suggests that cow management and housing impacts lameness (Espejo and
Endres, 2007) and in turn, longevity (Whay et al., 2003). Furthermore, lame cows given short-term
access to well-maintained pasture showed greater improvements in gait than those continuously
maintained in free stalls (Hernandez-Mendo et al., 2007). Thus, while pasture access should not be
considered a panacea for welfare issues in dairy cows, accommodation of natural living via even
temporary pasture may prove to be meaningful and beneficial for both cows and farmers.
Mastitis likewise poses a serious challenge for dairy production. As is the case for lameness,
mastitis is not only costly, but significantly impactful on cow welfare as it is associated with pain,
suffering and ultimately, reduced cow longevity. A survey of US dairy producers indicated that
over 26% of dairy cows culled were lost because of udder health or mastitis problems, and mastitis
was also a major cause of cow deaths (USDA, 2002); in 2007, 23% of cows were culled for udder
health issues (USDA, 2008). In 2002, clinical mastitis was found to be the most prevalent of all dis-
eases impacting dairy cows; the percentage of clinical mastitis cases remained unchanged in 2013
(USDA, 2016b), with almost all milk producers (99.7%) reporting at least one mastitis case.
In addition to raising questions pertaining to the “naturalness” of early and repeated calving,
the roles that environmental management, hygiene, and housing play in the prevalence of mastitis
cases must be considered. The complex interplay of contributing factors complicates resolution of
this welfare problem. However, pasture access again may offer some benefits relative to yielding
smaller numbers of cows with mastitis. For example, Washburn et al. (2002) found that cows main-
tained in confinement had almost twice the clinical mastitis numbers and eight times the culling
rate compared to those kept on pasture. It has been suggested that these differences may be due
to pastured cows potentially being exposed to fewer environmental pathogens than those housed
indoors (Smith and Hogan, 1994). It may also help that cows on pasture spend more time standing,
and less time lying down (Hernandez-Mendo et al., 2007), especially in areas that may have higher
pathogen loads. Coincidentally, the changes in lying versus standing time on pasture may also
facilitate recovery from lameness (Hernandez-Mendo et al., 2007). Thus, the case for incorporating
some aspects of natural living, such as pasture access, becomes stronger, as doing so may not only
better align with the telos of the cow, but may also improve her health and longevity.
Exclusively focusing on single-trait selection (such as exceptionally high milk production)
has been shown to impair cow health, reproductive performance, increase veterinary costs, and
decrease longevity (Phuong et al, 2016). These outcomes should not be surprising as it is well
documented that animals selected for very high production efficiency are at greater risk of develop-
ing behavioral, physiological, and immunological problems (Rauw et al., 1998). Course-correction