{"id":{"repo_id":"vt","oai_identifier":"oai:vtechworks.lib.vt.edu:10919/71229"},"canonical_url":"https://search.dev.ndltd.org/etd/vt/oai:vtechworks.lib.vt.edu:10919/71229","repository":{"repo_id":"vt","name":"Virginia Tech","base_url":"https://vtechworks.lib.vt.edu/oai/request"},"display":{"title":"Relationships between somatic cell counts and milk production in dairy cattle","abstract":"Monthly milk production data collected by DHI supervisors in 28 Virginia dairy herds over a three year period were analyzed. Relationships between somatic cell count and milk production were determined. A curvilinear relationship between somatic cell count and daily milk yield was shown to exist. The relationship indicated daily milk yield declined more rapidly as somatic cell counts increased from 50 X 10³ through 300 X 10³ cells per ml compared to daily milk decline as somatic cell counts rose from 400 X 10³ through 1,200 X 10³ cells per ml. Daily milk yield declined at a slower rate at somatic cell levels above 400 X 10³ cells per ml. There was an apparent cumulative or continual relationship between somatic cell count and daily milk yield. Losses and declines in test day milk production were greater when cumulative somatic cell count was considered. Complete lactation records of 305-day, mature equivalent milk production were compared to weighted, lactational somatic cell counts. Lactational milk production losses were not as great as daily milk production losses, extended to full lactation, indicated. Design difficulties and inadequacies of models used in complete lactation evaluation may explain the discrepancies. A maximum somatic cell count of 150 X 10³ to 200 X 10³ cells per ml was indicated as an optimum level for somatic cell count. Above this level milk losses were excessive.","abstract_html":"Monthly milk production data collected by DHI supervisors in 28 Virginia dairy herds over a three year period were analyzed. Relationships between somatic cell count and milk production were determined. A curvilinear relationship between somatic cell count and daily milk yield was shown to exist. The relationship indicated daily milk yield declined more rapidly as somatic cell counts increased from 50 X 10³ through 300 X 10³ cells per ml compared to daily milk decline as somatic cell counts rose from 400 X 10³ through 1,200 X 10³ cells per ml. Daily milk yield declined at a slower rate at somatic cell levels above 400 X 10³ cells per ml. There was an apparent cumulative or continual relationship between somatic cell count and daily milk yield. Losses and declines in test day milk production were greater when cumulative somatic cell count was considered. Complete lactation records of 305-day, mature equivalent milk production were compared to weighted, lactational somatic cell counts. Lactational milk production losses were not as great as daily milk production losses, extended to full lactation, indicated. Design difficulties and inadequacies of models used in complete lactation evaluation may explain the discrepancies. A maximum somatic cell count of 150 X 10³ to 200 X 10³ cells per ml was indicated as an optimum level for somatic cell count. Above this level milk losses were excessive.","abstract_has_math":false,"creators":["Clabaugh, Gregory Arthur"],"institution":"Virginia Polytechnic Institute and State University","degree_name":"Master of Science","degree_level":"masters","degree_discipline":"Dairy Science","degree_department":"Dairy Science","school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":1981,"date_issued":"1981","date_published":"1981","updated_at":"2026-07-22T22:19:15Z","subjects":[],"languages":["en_US"],"rights":["In Copyright"],"rights_urls":["http://rightsstatements.org/vocab/InC/1.0/"],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/10919/71229","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.department","label":"Department","values":["Dairy Science"]},{"key":"dc:creator","label":"Author","values":["Clabaugh, Gregory Arthur"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2016-05-23T17:53:57Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2016-05-23T17:53:57Z"]},{"key":"dc:date.issued","label":"Date","values":["1981"]},{"key":"dc:publisher","label":"Institution","values":["Virginia Polytechnic Institute and State University"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"dc:type.dcmitype","label":"Dc Type Dcmitype","values":["Text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Dairy Science"]},{"key":"thesis:degree_level","label":"Degree Level","values":["masters"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Virginia Polytechnic Institute and State University"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["en_US"]},{"key":"dc:rights","label":"Dc Rights","values":["In Copyright"]},{"key":"dc:rights.uri","label":"Rights URI","values":["http://rightsstatements.org/vocab/InC/1.0/"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/10919/71229"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Monthly milk production data collected by DHI supervisors in 28 Virginia dairy herds over a three year period were analyzed. Relationships between somatic cell count and milk production were determined. A curvilinear relationship between somatic cell count and daily milk yield was shown to exist. The relationship indicated daily milk yield declined more rapidly as somatic cell counts increased from 50 X 10³ through 300 X 10³ cells per ml compared to daily milk decline as somatic cell counts rose from 400 X 10³ through 1,200 X 10³ cells per ml. Daily milk yield declined at a slower rate at somatic cell levels above 400 X 10³ cells per ml. There was an apparent cumulative or continual relationship between somatic cell count and daily milk yield. Losses and declines in test day milk production were greater when cumulative somatic cell count was considered. Complete lactation records of 305-day, mature equivalent milk production were compared to weighted, lactational somatic cell counts. Lactational milk production losses were not as great as daily milk production losses, extended to full lactation, indicated. Design difficulties and inadequacies of models used in complete lactation evaluation may explain the discrepancies. A maximum somatic cell count of 150 X 10³ to 200 X 10³ cells per ml was indicated as an optimum level for somatic cell count. Above this level milk losses were excessive."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["Master of Science"]},{"key":"dc:format.mimetype","label":"Dc Format Mimetype","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Relationships between somatic cell counts and milk production in dairy cattle"]}]}],"canonical_facts":{"dc:contributor.department":["Dairy Science"],"dc:creator":["Clabaugh, Gregory Arthur"],"dc:date.accessioned":["2016-05-23T17:53:57Z"],"dc:date.available":["2016-05-23T17:53:57Z"],"dc:date.issued":["1981"],"dc:description.abstract":["Monthly milk production data collected by DHI supervisors in 28 Virginia dairy herds over a three year period were analyzed. Relationships between somatic cell count and milk production were determined. A curvilinear relationship between somatic cell count and daily milk yield was shown to exist. The relationship indicated daily milk yield declined more rapidly as somatic cell counts increased from 50 X 10³ through 300 X 10³ cells per ml compared to daily milk decline as somatic cell counts rose from 400 X 10³ through 1,200 X 10³ cells per ml. Daily milk yield declined at a slower rate at somatic cell levels above 400 X 10³ cells per ml. There was an apparent cumulative or continual relationship between somatic cell count and daily milk yield. Losses and declines in test day milk production were greater when cumulative somatic cell count was considered. Complete lactation records of 305-day, mature equivalent milk production were compared to weighted, lactational somatic cell counts. Lactational milk production losses were not as great as daily milk production losses, extended to full lactation, indicated. Design difficulties and inadequacies of models used in complete lactation evaluation may explain the discrepancies. A maximum somatic cell count of 150 X 10³ to 200 X 10³ cells per ml was indicated as an optimum level for somatic cell count. Above this level milk losses were excessive."],"dc:description.degree":["Master of Science"],"dc:format.mimetype":["application/pdf"],"dc:identifier.uri":["http://hdl.handle.net/10919/71229"],"dc:language.iso":["en_US"],"dc:publisher":["Virginia Polytechnic Institute and State University"],"dc:rights":["In Copyright"],"dc:rights.uri":["http://rightsstatements.org/vocab/InC/1.0/"],"dc:title":["Relationships between somatic cell counts and milk production in dairy cattle"],"dc:type":["Thesis"],"dc:type.dcmitype":["Text"],"thesis:degree_discipline":["Dairy Science"],"thesis:degree_level":["masters"],"thesis:degree_name":["Master of Science"],"thesis:institution_name":["Virginia Polytechnic Institute and State University"]},"updated_at":"2026-07-22T22:19:15Z"}