Effects of teat dipping disinfectant containing biodegradable iodophor microspheres on preventing dry period intramammary infection in dairy cows

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(1)(2004) 44 1. Korea J Vet Res(2004) 44(1) : 113~120.

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(3) (: 2003 12 30) 1. Effects of teat dipping disinfectant containing biodegradable iodophor microspheres on preventing dry period intramammary infection in dairy cows Cheol-Yong Hwang, Jong-Min Kim, Hwa-Young Youn, Bo Han, and Hong-Ryul Han* College of Veterinary Medicine, Seoul National University, Seoul 151-742, Korea College of Veterinary Medicine, China Agricultural University, Beiijing 10094, China (Accepted December 30, 2003). 1. Abstract : 1% iodophor loaded microspheres of PLGA (Poly[DL-Lactide-co-Glycolide]) were prepared by solvent evaporation method and were applied to the cows on dry period for evaluating it’s preventive effects on intramammary infections. The morphology of the microspheres were evaluated using scanning electron microscopy and their releasing patterns were investigated. On investigating idophor releasing patterns of the microsphere, burst releasing pattern was detected until 2 days after in vitro incubation and sustained releasing was observed until 4 weeks. In field trial of teat dipping solution containing idophor loaded microspheres in dry cows showed significant preventive effects of intramammary infection caused by S. aureus, S. agalactiae, coagulase negative Staphylococci and coliform bacteria (p<0.05). Key words : microsphere, teat dipping solutin, iodophor, dairy cow. . W s tu vw E 5 ; xK l )y

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(23) iodophor microsphere ! "# $%&' (" )*. 115. Table 1. Vermont teat skin and teat end evaluation system TEAT END CONDITION SCORING 0. Teat end has been subjected to physical or chemical injury(e.g. stepped on or frostbitten) not related to treatment or the quarter is nonlactating.. 1. Teat end sphincter is smooth with no evidence of irritation.. 2. Teat end has a raised ring.. 3. Teat end sphincter is roughened with slight cracks but no redness is present.. 4. Teat end sphincter is inverted with many cracks, giving a “flowered” appearance. Teat end may have old but healing scabs.. 5. Teat end is severely damaged and ulcerative with scabs or open lesions. Large or numerous warts are present that interfere with teat end function. TEAT SKIN CONDITION SCORING. 0. Teat skin has been subjected to physical injury(e.g. stepped on or frostbitten) not related to the treatment or the quarter is nonlactating.. 1. Teat skin is smooth and free from scales, cracks, or chapping.. 2. Teat skin shows some evidence of scaling.. 3. Teat skin is chapped. Some small warts may be present.. 4. Teat skin is chapped and cracked. Redness, indicating inflammation, is present. Numerous warts may be present.. 5. Teat skin is severely damaged and ulcerative with scabs or open lesions. Large or numerous warts are present that interfere with teat end function.. Ù,- )y$ J}×,4 D/ V 10% + U 1% idophor Ù,- )y$ à}×P. V )y 0 cloxacillin + b gh (êùa 500 , Virbac, France)$ ¹×P. #X V; D/ VW V V_ v 1A, V 0Ê èH %& â ×,4 áâU 5% calf blood\ 0.1% esculin ªKU Ù

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(29) ¾}Ä Ê àVQ ¹ áâE "òÙW 265 nm D ôL õvE Table 2. Iodophor encapsulation efficiency of PLGA microspheres prepared with solvent evaporation method (wave length=265 nm) Number Absorbance of sample 1 2 3. 0.47 0.46 0.51. Standard absorbance. Encapsulation efficiency. 0.69 (1 g/100 ml). 69.6%. ów 0.48- 1% iodophor ÙW ó w 0.69$ [,- ~ G/U iodophor-loaded microsphere 10 mgW iodophor (LÈ 69.6%P(Table 2). Table 3. Releasing pattern of iodophor in microshperes expressed by mean absorbance Time 0 1 2 3 4 7 14 21 28. day day days days days days days days days. Mean absorbance 0.142 0.474 0.395 0.216 0.206 0.197 0.177 0.292 0.332. Fig. 2. Scanning electron micrograph showing the change in surface morphology in vitro incubation. A : 1day (×150), B : 1week (×350). C : 3weeks (×350), D : 4week (×350)..

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(35) %E ¸W = 7 G}h lP. W )$E µ Ô" microsphereW qr qr K!Ó û VØh l ¸ = W& 8« µkÜ ¡ ³,. Table 4. Effects of teat dipping disinfectant for preventing of dry period new intramammary infection in dairy cows Groups Treatment Control Total. No. of Quarters 331 334 665. Organism S. aureus a. 9 32 41. *CNS : coagulase negative staphylococci species. a Statistical difference from controls (p<0.05).. S. agalactiae 5 18 23. a. CNS* 19 40 59. a. other streptococci. Coliforms. 3 9 12. 1a 7 8.

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(54) 1. Arshady, R. Microspheres and microcapsules, a survey of manufacturing techniques : Part III Solvent evaporation. Poly. Eng. Sci. 1990, 30, 915-924. 2. Boddie, R. L. and Nickerson, S. C. Efficacy of two iodophor postmilking teat germicides against Streptococcus agalactiae. J. Dairy Sci. 1990, 73, 27902793. 3. Coti, B., Pavanetto, F. and Genta I. Use of polylactic acid for the preparation of microparticulate drug delivery system. J. Microencapsulation. 1992, 9, 153166. 4. Craven, N. Efficacy and Financial Value of Antibiotic Treatment of Bovine Clinical Mastitis during Lactationa Review. Br. Vet. J. 1987, 143, 410-422. 5. Dodd, F. H., Westgarth, D. R., Neave, F. K. and Kingwill, R. G. Mastitis - the strategy of control. J. Dairy Sci. 1969, 52, 689-691. 6. Gottardi, W. Disinfection, sterilization and preservation pp.183, 3rd ed. Lippincott, Philadelphia, 1983. 7. Heller, J. Biodegradable polymers in controlled drug delivery. CSC Crit. Rev. Ther. Drug Carrier Systems, 1984, 1, 39-90. 8. Jeffery, H., Davis, S. S. and O'Hagan, D. T. The preparation and characterization of poly(lactide-coglycolide) microparticle I : Oil-in-water emulsion solvent evaporation. Int. J. Pharm. 1991, 77, 169-175. 9. Johnson, P. and Lloyed-Jones, J. G. Drug delivery systems, pp. 12-55, 1st ed. Ellis Horwood, England Chicheste, 1987. 10. Kingwill, R. G., Neave, F. K., Dodd, F. H., Griffin, T. K. and Westgarth, D. R. The effect of a mastitis control system of levels of subclinical and clinical mastitis in two years. Vet. Rec. 1993, 87, 94-98. 11. Linhardt, R. J. Polymers and Aggregate systems, pp. 53-96, VCH Publishers, New York, 1988. 12. Mehta, R. C., Jeyanthi, R. S., Calis, B. C., Thanoo,.

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