Effect Of Dinitolmide Intercalated Into Montmorillonite On E.Tenella Infection In Chickens

Avian coccidiosis is a parasitic disease that affects the poultry industry worldwide. The normal control strategies have relied on prophylactic medication. But due to the drug resistant emergence of the parasites, novel approached are urgently wanted to study on the coccidiosis control. This has a profound impact on the livestock breeding, animal products residue control and even the ecological environment.Dinitolmide (Zoalene,3,5-dinitro-o-toluamide) has good therapeutic effect on coccidium, especially Eimeria tenella. Some studies have reported grain size of the medicine has a great influence on its coccidiostatic efficacy and it has special physical and chemical properties. MMT, a natural clay mineral with fine grain and large inter-planar spacing in the (001) plane, has superior capability to intercalate large molecules into the interlayer space of the (001) plane. MMT with net negatively charge layers has good swelling property to intercalate positively charged bioactive compounds into the interlayer spaces by electrostatic interaction. The dinitolmide-MMT hybrids were synthesized by the method of solution intercalation via dinitolmide intercalated into Na+-montmorillonite (Na+-MMT). Its advantage was improving the anticoccidial effect of dinitolmide. The main contents and results of this study are as follows:(1) The characterization and optimization of preparation conditions of dinitolmide-MMT hybrids:The structure of hybrids was characterized by X-ray diffraction (XRD) and Fourier transformed infrared (FTIR). Compared with sodium-based MMT, diffraction peak of dinitolmide-MMT shifted from7.0414°to5.7858°, and the basal spacing of MMT increased from1.26nm to1.52nm. The characteristic peak of Si-O stretching (out-of-plane) in MMT at1037.82cm-1was shifted to higher frequencies. The absorption peak at1639.75cm-1of MMT which attributed to H-O-H bending band of the absorbed water was found to lower frequencies. The IR bands of amide group in dinitolmide were detected in dinitolmide-MMT at1533cm-1. Orthogonal optimization experiments derived the optimal reaction condition of dinitolmide-MMT drug feed ratio at0.75g/g, volume ratio of water and acetone is1, mechanical stirring time for8h, reaction temperature at40℃, reaction solution at pH=6, and yielded an intercalation capacity as high as395mg/g.(2) Test on the sporulation rate of E. tenella in vitro. Results showed that dinitolmide and dinitolmide-MMT hybrids had the same rate of oocysts ascosporic on average which were70.54%and70.06%, respectively. Thus the dinitolmide-MMT had good anticoccidiosis effect, which indicates that dinitolmide was desorbed from the clay mineral and diffused into the coccidium solution.(3) Evaluation of effectiveness in vivo. Dinitolmide-MMT anticoccidial effect was examined by E. tenella infection experiment. AA broiler Chickens were orally inoculated with E. tenella oocysts after dinitolmide was given in feed. Their curative effects were observed. The dinitolmide-MMT hybrid can significantly increase body weight gains and reduce bloody diarrhea, lesion score, and oocysts excretion (p<0.05). The anti-coccidia index (ACI) of dinitolmide-MMT hybrid was165.21. The dinitolmide-MMT showed higher anti-coccidian oocysts activity compared with dinitolmide. The dinitolmide-MMT hybrid systems can be more effective in control of coccidiosis in comparison to dinitolmide.