Effects on calves less than one month old of feeding or not feeding them during road transport of up to 24 hours

Abstract

Two trials, each involving 56 calves less than one month old, demonstrated that the responses of calves to food and water deprivation during 24 hours of transport were similar to those observed in older cattle and lambs. There was increasing utilisation of body reserves and a measurable increase in dehydration, coupled with an increased loss of liveweight. Feeding 1 litre of glucose/electrolyte solution at eight-hour intervals did reduce the effects of food and water deprivation, but it is suggested that the minor benefits of mid-transport feeding during a 24-hour journey would not justify the disruption that would be caused by unloading and feeding. It would be better to complete the journey in as short a time as possible, providing the calves were carried under suitable conditions. Liveweight and the levels of plasma beta-hydroxybutyrate, non-esterified fatty acids, total protein and albumin had all returned to approximately pre-transport values after 24 hours of recovery. However, the calves had not started to gain in liveweight until some time after 24 but before 72 hours of recovery. The calves did not show the same marked responses in heart rate, plasma cortisol and plasma glucose that are observed in older cattle and in other species. They also appeared to be unable to regulate their body temperature closely, when they were transported during the winter. It is suggested that their lack of response to transport was not because they were unaffected but because they were physiologically unadapted to coping with transport.

Stress reactivity and its relationship to beef quality in Nguni steers supplemented with Acacia karroo leaves

“…The observed concentrations of post-mortem catecholamines in steers that relied on natural pasture alone were higher than those that were reported by Ndlovu et al (2008) and Muchenje et al (2009). The variation could be due to the differences in age-related responses to pre-slaughter stress (Knowles et al, 1997). Nguni steers in this study were 3 months older at slaughter compared with those used by Ndlovu et al (2008) and Muchenje et al (2009).…”

Road transport of farm animals: effects of journey duration on animal welfare

“…Lack of stress responses in some of the investigations mentioned above is therefore not evidence that transport is not stressful for calves in this age group. There are, however, investigations that do find effects (Grigor et al, 2001), whereas others do not find effects (Knowles et al, 1997) of transport on typical physiological measures of stress such as plasma cortisol concentration. These divergent results may be due to differences in the developmental stage of the calves, highlighting the difficulties in using these measures to assess welfare in young animals.…”

Invited review: Relationship between cattle transport, immunity and respiratory disease

“…Swanson and Morrow-Tesch (2001) reported that young cattle exhibit increased mortality and morbidity during transportation compared with older cattle due to a lack of exposure to the new environment and a naive immune system. In contrast, Knowles et al (1997) found a negative correlation between age at transport and mortality. Although the BRDC is a multifactorial condition, it is arguably of greatest importance to gain a better understanding of the mechanisms that drive the compromised immune function that first allows invasion of opportunistic pathogens (Caswell, 2014).…”