tylvalosin and Body-Weight

The study was carried out under field conditions in a commercial farm, and 1,440 as-hatched Ross-308 broilers were included. Broilers were randomly distributed into 24 experimental 4-m(2) pens (60 broilers/pen). Pens were randomized to the 3 treatment groups: a) tylvalosin 10 mg/kg of live BW during 2 d, b) positive control (tylosin during 2 d), and c) negative control (no treatment). The drugs were provided in the water supply. Mortality, individual BW, and feed intake were assessed. Clostridium presence was assessed in fecal and cecal samples, coccidian oocyst counts were assessed in fecal samples, and bacterial diversity was assessed in ileal content. Live BW at 42 d old was significantly better in the tylvalosin group than in tylosin and no-treatment groups, with tylvalosin-treated broilers reaching 80 to 100 g higher final live weight. Average daily gain results mirrored BW findings. The improvement of feed conversion rate with tylvalosin amounted to 0.13 and to 0.10 versus tylosin and no-treatment, respectively, with mortality being similar in all groups. Significantly reduced sulfite-reducing Clostridium and Clostridium perfringens counts in tylvalosin and tylosin groups versus the no-treatment group were observed in cecum content samples. In conclusion, according to the present study results, tylvalosin, at doses substantially lower than registered for poultry in Europe, has proven effective in controlling the colonization of the cecum by Clostridium ssp. in broilers, improving some productive performances.

Topics: Animals; Anti-Bacterial Agents; Bacteria; Biodiversity; Body Weight; Cecum; Chickens; Clostridium Infections; Clostridium perfringens; Coccidiosis; Colony Count, Microbial; DNA, Bacterial; Dose-Response Relationship, Drug; Eating; Eimeria; Feces; Feeding Behavior; Ileum; Intestinal Diseases; Parasite Egg Count; Polymerase Chain Reaction; Polymorphism, Restriction Fragment Length; Poultry Diseases; RNA, Ribosomal, 16S; Tylosin

The effect of a water-soluble formulation of tylvalosin (Aivlosin® 625 mg/g granules) on disease caused by porcine reproductive and respiratory syndrome virus (PRRSV) and Mycoplasma hyopneumoniae (Mhyop) was investigated in two animal studies. In a PRRSV challenge model in pregnant sows (n = 18), six sows received water medicated at target dose of 5 mg tylvalosin/kg body weight/day from 3 days prior to challenge until the end of gestation. Six sows were left untreated, with a third group remaining untreated and unchallenged. Sows were challenged with PRRSV-2 at approximately 85 days of gestation. Cytokines, viremia, viral shedding, sow reproductive parameters and piglet performance to weaning were evaluated. In a dual infection study (n = 16), piglets were challenged with Mhyop on days 0, 1 and 2, and with PRRSV-1 on day 14 and euthanized on day 24. From day 10 to 20, eight piglets received water medicated at target dose of 20 mg tylvalosin/kg body weight/day and eight piglets were left untreated. Cytokines, viremia, bacteriology and lung lesions were evaluated.. Overall, tylvalosin reduced both local and systemic proinflammatory cytokines after challenge with respiratory pathogens in sows and in piglets. Tylvalosin was effective in reducing Mhyop recovery from the lungs and may reduce virus shedding in piglets following transplacental PRRSV infection in sows.

Topics: Animals; Body Weight; Cytokines; Female; Granulocyte-Macrophage Colony-Stimulating Factor; Interleukin-10; Interleukin-12; Interleukin-8; Mycoplasma hyopneumoniae; Porcine Reproductive and Respiratory Syndrome; Porcine respiratory and reproductive syndrome virus; Pregnancy; Swine; Swine Diseases; Tumor Necrosis Factor-alpha; Viremia