{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,22]],"date-time":"2026-10-22T16:52:14Z","timestamp":1792687934820,"version":"4.5.0"},"reference-count":38,"publisher":"American Veterinary Medical Association (AVMA)","issue":"10","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["ajvr"],"published-print":{"date-parts":[[2001,10,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>\n                    <jats:bold>Objective<\/jats:bold>\n                    \u2014To determine the total number of\n                    <jats:italic>Cryptosporidium parvum<\/jats:italic>\n                    oocysts and\n                    <jats:italic>Giardia<\/jats:italic>\n                    spp\ncysts shed by dairy calves during the period when\nthey are most at risk after natural infection.\n                  <\/jats:p>\n                  <jats:p>\n                    <jats:bold>Animals<\/jats:bold>\n                    \u2014478 calves naturally infected with\n                    <jats:italic>C parvum<\/jats:italic>\n                    and 1,016 calves naturally infected with\n                    <jats:italic>Giardia<\/jats:italic>\n                    spp.\n                  <\/jats:p>\n                  <jats:p>\n                    <jats:bold>Procedure<\/jats:bold>\n                    \u2014Oocysts or cysts were enumerated from\nfecal specimens. Distribution of number of oocysts or\ncysts versus age was used to determine the best fitting\nmathematic function. Number of oocysts or cysts\nper gram of feces for a given duration of shedding\nwas computed by determining the area under the\ncurve. Total number of oocysts or cysts was calculated\nby taking the product of the resultant and the\nexpected mass of feces.\n                  <\/jats:p>\n                  <jats:p>\n                    <jats:bold>Results<\/jats:bold>\n                    \u2014Intensity of\n                    <jats:italic>C parvum<\/jats:italic>\n                    oocyst shedding was\nbest described by a second-order polynomial function.\nShedding increased from 4 days of age, peaked\nat day 12, and then decreased. An infected 6-day-old\ncalf would produce 3.89 X 10\n                    <jats:sup>10<\/jats:sup>\n                    oocysts until 12 days\nold. Pattern of shedding of\n                    <jats:italic>Giardia<\/jats:italic>\n                    spp cysts was best\ndescribed by exponential functions. Intensity of shedding\nincreased from 4 days of age, peaked at day 14,\nand then decreased. An infected calf would produce\n3.8 X 10\n                    <jats:sup>7<\/jats:sup>\n                    cysts from day 50 until day 56.\n                  <\/jats:p>\n                  <jats:p>\n                    <jats:bold>Conclusion and Clinical Relevance<\/jats:bold>\n                    \u2014The large\nnumber of oocysts and cysts shed indicates that\nshedding by dairy cattle poses a risk for susceptible\ncalves and people. Estimates reported here may be\nuseful to aid in designing cost-effective strategies to\nmanage this risk. (\n                    <jats:italic>Am J Vet Res<\/jats:italic>\n                    2001;62:1612\u20131615)\n                  <\/jats:p>","DOI":"10.2460\/ajvr.2001.62.1612","type":"journal-article","created":{"date-parts":[[2005,12,7]],"date-time":"2005-12-07T06:39:46Z","timestamp":1133937586000},"page":"1612-1615","source":"Crossref","is-referenced-by-count":126,"title":["Number of Cryptosporidium parvum oocysts or Giardia spp cysts shed by dairy calves after natural infection"],"prefix":"10.2460","volume":"62","author":[{"given":"Daryl V.","family":"Nydam","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Susan E.","family":"Wade","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stephanie L.","family":"Schaaf","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hussni O.","family":"Mohammed","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1272","reference":[{"key":"p_1_447","doi-asserted-by":"crossref","first-page":"139","DOI":"10.1016\/0020-7519(94)E0059-V","volume":"25","author":"O'Donoghue PJ","year":"1995","journal-title":"Int J Parasitol"},{"key":"p_2_448","doi-asserted-by":"crossref","first-page":"807","DOI":"10.1093\/oxfordjournals.aje.a009015","volume":"144","author":"Colford","year":"1996","journal-title":"Am J Epidemiol"},{"key":"p_3_449","doi-asserted-by":"crossref","first-page":"231","DOI":"10.1093\/infdis\/162.1.231","volume":"162","author":"Buret A","year":"1990","journal-title":"J Infect Dis"},{"key":"p_4_450","doi-asserted-by":"publisher","DOI":"10.1016\/S0020-7519(99)00076-4"},{"key":"p_5_451","first-page":"46","author":"Bungert K","year":"1998","journal-title":"Dairy Herd Management"},{"key":"p_6_452","doi-asserted-by":"publisher","DOI":"10.2460\/javma.2000.217.658"},{"key":"p_7_453","doi-asserted-by":"publisher","DOI":"10.1016\/S0304-4017(99)00111-9"},{"key":"p_8_454","doi-asserted-by":"crossref","first-page":"51","DOI":"10.3201\/eid0301.970106","volume":"3","author":"Guerrant RL.","year":"1997","journal-title":"Emerg Infect Dis"},{"key":"p_9_455","doi-asserted-by":"crossref","first-page":"988","DOI":"10.2460\/ajvr.1994.55.07.988","volume":"55","author":"Barr SC","year":"1994","journal-title":"Am J Vet Res"},{"key":"p_10_456","doi-asserted-by":"crossref","first-page":"706","DOI":"10.1128\/mr.55.4.706-732.1991","volume":"55","author":"Adam RD","year":"1991","journal-title":"Microbiol Rev"},{"key":"p_11_457","doi-asserted-by":"publisher","DOI":"10.1016\/0304-4017(93)00645-F"},{"key":"p_12_458","doi-asserted-by":"publisher","DOI":"10.1016\/S0304-4017(96)01072-2"},{"key":"p_13_459","unstructured":"Fayer R, Dubey JP. The general biology of Cryptosporidium. In: Fayer R, ed. Cryptosporidium and cryptosporidiosis. Boca Raton, Fla: CRC Press, 1997;1-41."},{"key":"p_14_460","doi-asserted-by":"crossref","first-page":"2032","DOI":"10.2105\/AJPH.87.12.2032","volume":"87","author":"Hoxie NJ","year":"1997","journal-title":"Wisconsin. Am J Public Health"},{"key":"p_15_461","unstructured":"Ungar BLP. Cryptosporidiosis in humans. In: Dubey JP, Fayer R, eds. Cryptosporidiosis in man and animals. Boca Raton, Fla: CRC Press, 1990;59-82."},{"key":"p_16_462","doi-asserted-by":"crossref","first-page":"12","DOI":"10.1177\/030098587801500102","volume":"15","author":"Snyder SP","year":"1978","journal-title":"Vet Pathol"},{"key":"p_17_463","first-page":"899","volume":"125","author":"Keusch GT","year":"1995","journal-title":"Schweiz Med Wochenschr"},{"key":"p_18_464","doi-asserted-by":"crossref","first-page":"44","DOI":"10.2307\/3284315","volume":"83","author":"Hopkins RM","year":"1997","journal-title":"J Parasitol"},{"key":"p_19_465","doi-asserted-by":"crossref","first-page":"567","DOI":"10.3201\/eid0304.970423","volume":"3","author":"Peng MM","year":"1997","journal-title":"Emerg Infect Dis"},{"key":"p_20_466","doi-asserted-by":"crossref","first-page":"3255","DOI":"10.1128\/JCM.36.11.3255-3259.1998","volume":"36","author":"Spano F","year":"1998","journal-title":"J Clin Microbiol"},{"key":"p_21_467","doi-asserted-by":"publisher","DOI":"10.1007\/s004360050399"},{"key":"p_22_468","doi-asserted-by":"publisher","DOI":"10.1086\/315279"},{"key":"p_23_469","unstructured":"Blagburn BL. Prophylaxis and chemotherapy: human and animal. In: Fayer R, ed. Cryptosporidium and cryptosporidiosis. Boca Raton, Fla: CRC Press, 1997;111-128."},{"key":"p_24_470","doi-asserted-by":"crossref","first-page":"384","DOI":"10.2460\/ajvr.1997.58.04.384","volume":"58","author":"O'Handley RM","year":"1997","journal-title":"Am J Vet Res"},{"key":"p_25_471","doi-asserted-by":"crossref","first-page":"209","DOI":"10.1016\/S0304-4017(00)00200-4","volume":"89","author":"O'Handley RM","year":"2000","journal-title":"Vet Parasitol"},{"key":"p_26_472","doi-asserted-by":"publisher","DOI":"10.1046\/j.1365-3156.1997.d01-132.x"},{"key":"p_27_473","first-page":"D000217","volume":"2","author":"Zaat JO","year":"2000","journal-title":"Cochrane Database Syst Rev"},{"key":"p_28_474","doi-asserted-by":"publisher","DOI":"10.1016\/S0020-7519(97)00170-7"},{"key":"p_29_475","doi-asserted-by":"crossref","first-page":"391","DOI":"10.2460\/javma.1999.214.03.391","volume":"214","author":"O'Handley RM","year":"1999","journal-title":"J Am Vet Med Assoc"},{"key":"p_30_476","first-page":"267","author":"Georgi JR","year":"1990","journal-title":"Philadelphia: WB Saunders Co"},{"key":"p_31_477","unstructured":"SAS OnlineDoc, version 7.0 CD-ROM, SAS Institute Inc, Cary, NC, 1998."},{"key":"p_32_478","first-page":"22","author":"Fayer R","year":"2000","journal-title":"Large Anim Pract"},{"key":"p_33_479","doi-asserted-by":"publisher","DOI":"10.1017\/S0031182099004746"},{"key":"p_34_480","doi-asserted-by":"publisher","DOI":"10.1016\/0304-4017(84)90011-6"},{"key":"p_35_481","doi-asserted-by":"publisher","DOI":"10.1016\/S0304-4017(00)00337-X"},{"key":"p_36_482","first-page":"703","volume":"38","author":"Olson ME","year":"1997","journal-title":"Can Vet J"},{"key":"p_37_483","doi-asserted-by":"publisher","DOI":"10.1056\/NEJM199503303321304"},{"key":"p_38_484","doi-asserted-by":"crossref","first-page":"157","DOI":"10.4269\/ajtmh.1999.60.157","volume":"60","author":"Chappell CL","year":"1999","journal-title":"Am J Trop Med Hyg"}],"container-title":["American Journal of Veterinary Research"],"original-title":[],"link":[{"URL":"https:\/\/avmajournals.avma.org\/view\/journals\/ajvr\/62\/10\/ajvr.2001.62.1612.xml","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/avmajournals.avma.org\/downloadpdf\/journals\/ajvr\/62\/10\/ajvr.2001.62.1612.xml","content-type":"text\/html","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/avmajournals.avma.org\/downloadpdf\/journals\/ajvr\/62\/10\/ajvr.2001.62.1612.xml","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,3,7]],"date-time":"2025-03-07T07:53:27Z","timestamp":1741334007000},"score":1,"resource":{"primary":{"URL":"https:\/\/avmajournals.avma.org\/view\/journals\/ajvr\/62\/10\/ajvr.2001.62.1612.xml"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2001,10,1]]},"references-count":38,"journal-issue":{"issue":"10"},"URL":"https:\/\/doi.org\/10.2460\/ajvr.2001.62.1612","relation":{},"ISSN":["0002-9645"],"issn-type":[{"value":"0002-9645","type":"print"}],"subject":[],"published":{"date-parts":[[2001,10,1]]}}}