Transport of L‐valine by the chicken caecum

1. We have studied L‐valine transport by the caecal segments of 6‐ to 8‐week‐old chickens. Isolated enterocytes from the proximal caecum incubated with 0.1 mM L‐valine can accumulate the substrate against a concentration gradient. After 50 min incubation, the intracellular L‐valine concentration reached 0.53 mM, a value higher than that observed in enterocytes from the jejunum (0.34 mM; P< 0.01).

2. Enterocytes from the medial and distal caecal regions are unable to transport L‐valine uphill (cell concentration: 0.1 mM).

3. Amino acid accumulation by proximal caecal cells was Na⁺‐dependent and was inhibited by ouabain and 2,4‐dinitrophenol. L‐methionine inhibits L‐valine uptake and a 2.5 mM concentration abolishes the capacity of enterocytes to accumulate the substrate.

4. The high accumulation ratios shown by the proximal caecum for L‐valine suggest a role for this intestinal segment in the absorption of neutral amino acids present in the caecal chamber.     

The new E.U. Animal Transport Regulation: improved welfare and health or increased administration?

There is public discussion of the new E.U. Animal Transport Regulation No 1/2005 of Dec. 2004 and its advantages and draw-backs. This Regulation is no longer a Directive, so that it is directly applicable in the Members States. Although the Regulation is recognised to have great potential to improve welfare and health of transported animals, it will also increase administrative work. Most improvements will come through better education and the increased responsibilities of animal attendants, drivers, keepers and transport organisers, and through the stricter control mechanisms (log book, training, instructions etc.) and the introduction of the GPS control systems to further enhance the transparency of animal movements. The formats of the transport certificates used in all Member States will be harmonised. Technical records will be kept on air temperature and water consumption. Contact offices in all member states for transport affairs will improve the exchange of data between the responsible authorities and harmonise control and surveillance practice. Specific regulations are now in place for horses (broken, unbroken, registered) and for the transport age of young animals (piglets, lambs, calves, foals). In spite of some substantial improvements there are still significant gaps in our knowledge of both normal and long transports, for example optimal journey times, food and water supply on long transports, environmental factors such as vibration, motion, light and ventilation requirements in different European geographical regions. The same is true for the epidemiological aspects of the prevention of disease transmission; for example, very little is known about the bacterial and particulate emissions of the animal transport vehicles which travel across Europe. A serious drawback of the regulation is the fact that it does not abolish the unloading of animals on long transports to rest for 24 h at staging points, so that the concomitant risks to health and welfare remain, as do the opportunities for the transmission of infectious diseases at these stations. Two examples are given that demonstrate the physiological (heart rate) and biochemical (cortisol) reactions of cattle during transport. It seems useful to observe how the new Regulation affects practice and to assess the usefulness and practicability of the new rules after one or two years of operation. At the same time, more detailed research should be carried out in order to further adapt the Regulation to the needs of the animal species and gender in terms of travel time periods, food supply and resting schemes. This should also include reconsideration of loading and unloading rules in staging points on long journeys for all animals, particularly in view of risks of injury and transmission of infectious diseases. Investigations should be carried out to improve our understanding of the bio-aerosol emissions from driving and standing vehicles. Transport schemes on long journeys should be more closely adapted to the needs of the animals. The new Regulation represents another step forward toward improved animal welfare during transport in spite of some increase in the administrative measures required. It is necessary to bring together veterinary and animal science, engineering, logistics and practical and technical experience in order to improve the Regulation and the health and welfare of animals during transport.