Environment and the Sheep. The Welfare of Sheep. Dordrecht: Springer Netherlands; 2008. pp. 41-79. [DOI: 10.1007/978-1-4020-8553-6_2]

Welfare of small ruminants during transport

In the framework of its Farm to Fork Strategy, the Commission is undertaking a comprehensive evaluation of animal welfare legislation. The present Opinion deals with the protection of small ruminants (sheep and goats) during transport. The main focus is on welfare of sheep during transport by road but other means of transport and concerns for welfare of goats during transport are also covered. Current practices related to transport of sheep during the different stages (preparation, loading and unloading, transit and journey breaks) are described. Overall, 11 welfare consequences were identified as being highly relevant for the welfare of sheep during transport based on severity, duration and frequency of occurrence: group stress, handling stress, heat stress, injuries, motion stress, predation stress, prolonged hunger, prolonged thirst, restriction of movement, resting problems and sensory overstimulation. These welfare consequences and their animal-based measures are described. A wide variety of hazards, mainly relating to inappropriate or aggressive handling of animals, structural deficiencies of vehicles and facilities, unfavourable microclimatic and environmental conditions and poor husbandry practices, leading to these welfare consequences were identified. The Opinion contains general and specific conclusions in relation to the different stages of transport. Recommendations to prevent hazards and to correct or mitigate welfare consequences have been developed. Recommendations were also developed to define quantitative thresholds for microclimatic conditions within the means of transport and spatial thresholds (minimum space allowance). The development of welfare consequences over time were assessed in relation to maximum journey time. The Opinion covers specific animal transport scenarios identified by the European Commission relating to the export of sheep by livestock vessels, export of sheep by road, roll-on-roll-off vessels and 'special health status animals', and lists welfare concerns associated with these.

Review: Water stress in sheep raised under arid conditions

Chedid, M., Jaber, L. S., Giger-Reverdin, S., Duvaux-Ponter, C. and Hamadeh, S. K. 2014. Review: Water stress in sheep raised under arid conditions. Can. J. Anim. Sci. 94: 243–257. Sheep breeds which are indigenous to arid and semi-arid regions are known for their ability to adapt to rustic environments, to climatic variations as well as to shortages in resources. Water scarcity, often combined with heat stress, is a common challenge facing these animals, causing physiological perturbations and affecting the animal's productivity. This review reports the effect of different forms of water stress on physiological indicators, blood parameters, thermoregulation and immunological status in sheep. Although the breed effect may be significant, the following are generally observed common responses: drop in feed intake and weight loss, increase in evaporative cooling through panting, production of a small volume of highly concentrated urine, haemoconcentration, high blood osmolality, and immunosuppression. Prolonged water shortage may affect lamb birth weight and survival, and lead to a decrease in milk production, especially in non-adapted breeds, which could lead to important economic losses, as reported in heat-stressed sheep husbandries. Novel stress alleviation approaches are also presented, such as vitamin C supplementation.

Current practices on sheep and beef farms in New Zealand for depriving sheep of feed prior to transport for slaughter

AIM

To assess current practices on sheep and beef farms that deprive sheep of feed prior to transport to facilitate effluent management and processing at slaughter.

METHODS

A national telephone survey of 122 sheep and 346 sheep and beef farmers was conducted in March and April 2010. They were asked how long sheep were held off green feed prior to transport and why, what environment the sheep were held in, and if that period ever varied.

RESULTS

Of the 468 respondents, 303 (65%) removed their sheep from green feed 3-12 h before transport for slaughter, with longer periods reported in the South than North Island. The main reasons given were to reduce the volume of effluent for transport operators (n=174), to prevent wool staining during transport (n=173), and that sheep were better suited to load and travel empty (n=171). Water was provided during feed deprivation by 313 farmers. The period of food deprivation could be altered in response to requirements of transporters and processors, the weather, and by the class of stock involved, although 115/468 (25%) farmers stated that they never changed their normal protocol.

CONCLUSIONS

Amongst survey respondents, common practices compared favourably with recommendations to reduce effluent during transportation. Previous studies have investigated the effects of fasting lambs whilst in lairage prior to slaughter and focussed on carcass quality such as carcass weight and tenderness. Changes in liveweight and gastrointestinal tract contents suggest feed deprivation reduces the risk of defaecation and urination contributing to the accumulation of effluent during transport and of carcass contamination during processing. However, the point at which that risk is acceptable to transport and processing is unclear. Fasting results in physiological changes indicative of altered metabolism but it is not clear when those changes are indicative of adaptation to food deprivation or metabolic depletion and compromised welfare. There may be opportunities to improve the logistics of livestock preparation, transport and processing.

Relationship between distribution of tapetum fibrosum and retinal pigment epithelium in the sheep eye

The tapetum lucidum is a light-reflective device improving visual sensitivity in mesopic vision. There have been few studies on tapetal distribution and its relationship with degree of pigmentation in the retinal pigment epithelium (RPE). In the present study, sheep's eyes were used for macroscopical observation of the tapetum, and then histological sections of the posterior eyecups were made to analyze the distribution of tapetal thickness and degree of pigmentation in the RPE. Macroscopically, with available light, the tapetum was located in the dorsal eye fundus to the optic disc and showed an L-shape with the horizontally elongated nasal part and the dorsally expanded temporal part. In photographs with a flash, the tapetal area expanded and showed a more triangular shape. The tapetum histologically consisted of layers of dense collagen fibers and was thicker in the temporal part than in the nasal part. The maximum tapetal thickness was approximately 70 microm. The histological tapetal area was similar to the tapetal shape with a flash light. The pigmentation of the RPE was divided into three types, nonpigmented, transitional, and pigmented areas. The nonpigmented area was similar to the tapetal shape with available light. It is suggested that approximately 55% of the histological tapetal area is covered with the nonpigmented area and is functional under a natural light condition. The functional tapetal area was similar to the L-shaped high-density area of retinal ganglion cells.