div class=ts-pagebutton class=gotoPage data-page=1Page 1button div class=ts-imageimg data-url=effect-of-exposure-of-very-young-calves-to-virulent-brucella-abortus-on-theirhtmlpage=1 data-page=1 class=ts-thumb lazyload alt=Page 1: Effect of Exposure of Very Young Calves to Virulent Brucella abortus on their Serological Response to Re-infection by the same Organism at 6 Months of Age loading=lazy src=data:imagegifbase64iVBORw0KGgoAAAANSUhEUgAAAAIAAAACCAQAAADYv8WvAAAAD0lEQVR42mP8X8AwAgiABKBAv+vAXklAAAAAElFTkSuQmCC data-src=https:reader030vdocumentsusreader030viewer2022020523575068271a28ab0f07aed690html5thumbnails1jpg width=140 height=200 divp© Nature Publishing Group1964pdiv