History of the use of antibiotic as growth promoters in European poultry feeds.

Use of antibiotics as growth promoters in animal feeds has been permitted in the member states of the European Union during the last 50 yr. However, concerns about development of antimicrobial resistance and about transference of antibiotic resistance genes from animal to human microbiota, led to withdraw approval for antibiotics as growth promoters in the European Union since January 1, 2006. This report analyzes the history of European legislation regarding the use of antibiotics in poultry feeds, since the first harmonization by Directive 70/524 until Regulation 1831/2003 deleted these substances from the European Register of additives permitted in feeds. The European support to recommendations of the World Health Organization, the Food and Agriculture Organization, and the World Organization for Animal Health for a ban on antimicrobial use in animal feeds is expected to favor other countries also phase these substances out.

Nutritive value of triticale fed to cockerels and chicks.

1. The chemical composition, and amino acid and starch bioavailabilities of 18 triticale varieties were studied. In addition, the water soluble pentosan (WSP) content of 8 varieties was determined. 2. A wide variation in protein (149 to 203 g/kg DM), starch (563 to 629 g/kg DM) and WSP (27.7 to 50.9 g/kg DM) was found between varieties. 3. The TMEn reproductibility was assessed in two laboratories, using Leghorn cockerels, Isabrown cockerels and 3-week-old chicks. There were no significant differences in the TMEn values (range 14.0 to 15.2 MJ/kg DM) between the two types of cockerel. The TMEn values of the varieties were similar for chicks (range 13.6 to 14.9 MJ/kg DM) and for cockerels, with the exception of one variety. 4. The bioavailability of starch (range 96.5 to 99.4%) of some varieties was higher for cockerels than for chicks. The mean bioavailability of amino acids for cockerels was 94.5%. 5. TMEn prediction equations were derived from the chemical composition of the varieties. Best-fit equations were obtained for starch (R2 = 0.62, RSD = 0.24), ash (R2 = 0.58, RSD = 0.25) and WSP (R2 = 0.52, RSD = 0.27).

Effect of tannins on starch digestibility and TMEn of triticale and semipurified starches from triticale and field beans.

1. The effects of field bean tannin-containing hulls (T-hulls), non-tannin hulls (NT-hulls) and tannin extract on starch digestibilities and TMEn of triticale and semipurified starches from triticale and field beans were evaluated with adult cockerels and 3-week-old-chicks. 2. For both cockerels and chicks, the digestibility and TMEn of semipurified starches from triticale were higher than those from beans. Starch digestibilities of triticales (range 99.1 to 97.7%), of semipurified starches from triticales (range 96.5 to 89.9%) and from field beans (range 75.4 to 71.6%) were similar for both cockerels and chicks. 3. The addition of NT-hulls improved, in general, the digestibility of semipurified starches for both chicks and cockerels, which suggests that fibre improves the digestion of semipurified starches. 4. The effects of tannins of T-hulls on semipurified starch from beans and from triticale were different. Tannins always decreased the digestibility and TMEn of semipurified starch from field beans but only decreased the digestibility and TMEn of semipurified starch from triticale when fed to chicks, but not when fed to cockerels. 5. The addition of tannin extract always decreased the digestibility of semipurified starches by a greater amount than T-hulls, which supports the idea that the effect of tannins depends on the quantity of tannin ingested.