... with limited infection of animals SPF lambs, advantages availability animals experimental particular haemolytica have would ready in animals P of animal animals sheep, of in haemolytica P with proved ... number and costly A model seasonal laboratory low and cost infection of available the small are is and throughout in of relative Unfortunately, year has haemolytica P a numbers of greater the with ... inocula OD Figure Standard A6 , Figure A7 and AB against Standard Al, curves of A2 curves and A5 of against P types haemolytica OD at 400nm types P haemolytica OD at 400 nm Co 0) ö Co ö a rö (0...