monensin and avilamycin

A live attenuated anticoccidial vaccine (Paracox) was compared with a nicarbazin-monensin anticoccidial drug shuttle programme in three crops of Italian broilers, comprising a total of 290,405 chickens. All birds received the antibiotic growth promoter avilamycin. No coccidiosis was evident during the trials, but the occurrence of oocysts in the litter demonstrated that a natural challenge was present. Vaccinated birds consistently performed at least as well as those treated with the anticoccidial drug shuttle. The final mean weights of vaccinated birds were significantly greater (P < 0.001) than those of birds treated with anticoccidial drugs, both for females at 36/37 days and males at 56 days. Feed conversion ratios, total mortality including culls, the proportion of rejects at the processing plant, and the moisture content of the litter were not significantly different between the two control methods. Growth curves showed that there was no post-vaccinal growth check in the vaccinated birds and no intolerance of the anticoccidial drug treatment. There was no overall seasonal effect, regardless of treatment, on the performance of the three crops reared from November 1997 to July 1998. These findings suggest that the use of this vaccine is likely to enable the replacement of anticoccidial drug shuttle programmes in broilers reared under conditions similar to those used in these Italian flocks.

Topics: Animal Feed; Animals; Chickens; Coccidiosis; Coccidiostats; Eimeria; Female; Italy; Male; Monensin; Nicarbazin; Oligosaccharides; Oocysts; Poultry Diseases; Protozoan Vaccines; Vaccination; Vaccines, Attenuated; Weight Gain

The aim of this study was to evaluate the effect of different antibiotics used as growth promoters on the control of porcine intestinal adenomatosis when administered in weaning, growing and fattening pig diets, according to Annex I of the European Union directive (70/524/EEC and its subsequent amendments to date) for the use of feed additives. On a farm with a previous history of proliferative enteropathy outbreaks, 648 weaned piglets (23 days old) were divided into nine experimental groups according to bodyweight and sex ratio, each group comprising four pens with 18 pigs in each pen. One group served the trial as a negative (unmedicated) control: another (the positive control) received monensin via feed at 100 p.p.m. up to the end of the growing phase (107 days old) and 50 p.p.m. up to slaughter age (156 days old). The remaining seven groups were offered feed with the addition of the following antibiotics: virginia-mycin (50-20 p.p.m.), avilamycin (40-20 p.p.m.), spiramycin (50-20 p.p.m.), zinc bacitracin (50-10 p.p.m.), avoparcin (40-20 p.p.m.), tylosin (40-20 p.p.m.) and salinomycin (60-30 p.p.m.), respectively. The performance of the pigs in the positive control group was very satisfying and among the highest in the trial, verifying earlier field studies. As a general conclusion it seems that all tested growth promoters had a beneficial effect compared with the untreated control, indicated by the decrease of mortality rate, the elimination of diarrhoeal incidence and the enhancement of growth performance, although the proliferative enteropathy control achieved by each substance was not always satisfactory. More specifically, the antibiotic growth promoters tested can be scaled according to their total efficacy as follows: 1. Salinomycin, tylosin, spiramycin; 2. Virginiamycin, zinc bacitracin, avilamycin; and 3. Avoparcin. Finally, it is considered that part of the growth promotion efficacy of the tested substances is due to their potential capacity to control porcine intestinal adenomatosis; thus, in future growth performance trials, the disease background of the trial farms must be examined, especially for porcine enteropathy challenges.

Topics: Abattoirs; Animals; Anti-Bacterial Agents; Antibiotic Prophylaxis; Bacitracin; Bacterial Infections; Disease Outbreaks; Female; Food, Fortified; Glycopeptides; Greece; Growth Substances; Ileitis; Ileum; Intestinal Mucosa; Male; Monensin; Oligosaccharides; Pyrans; Spiramycin; Swine; Swine Diseases; Tylosin; Virginiamycin

The effects of the growth promoters avoparcin and avilamycin and the ionophore anticoccidials maduramicin, narasin and monensin on the growth of Clostridium perfringens (Cp) in the caeca and on performance of broiler chickens were tested in 2 experiments. The supplements were fed as single feed additives or in some combinations. No clinical signs or lesions caused by coccidia were observed in any of the studies. All supplements had an antibacterial effect on Cp and improved growth rate significantly. Carcass yield of birds fed growth promoters avilamycin or avoparcin was significantly higher compared with birds fed anticoccidials. These data indicate that, what concerns bird performance, during good hygienic conditions supplementation with antibiotic growth promoters may not be necessary when the diet is supplemented with an anticoccidial with antibacterial effects.

Topics: Animal Feed; Animals; Anti-Bacterial Agents; Cecum; Chickens; Clostridium Infections; Clostridium perfringens; Coccidiostats; Glycopeptides; Growth Substances; Ionophores; Lactones; Monensin; Oligosaccharides; Poultry Diseases; Pyrans; Random Allocation