Production evaluation, environmental effect and problems in small scale dairy farms

摘要

Productionevaluation,environmentaleffectandproblemsnbsp;insmallscaledairyfarmsThesmall-scaledairyfarmshavebeennotmuchstudiedinMéxicoeventhoughtheyprovide35%ofthenationalmilkproduction.IntheMorelia-QuerendarovalleyinMichoacan,thereareabout7thousandofthesefarms.Amethodologywasdevelopedtoevaluateproduction,environmentaleffectsandrecognitionofthemainproblemsinnineofthesefarms.TheSILFIRAcomputerisedprogramwasusedtoanalysethedataandtheMexicanqualitywaternormswereusedtoevaluatetheenvironmentaleffect.Thesystemwascharacterisedashaving16.5animalunitsin6.4haofusefulagriculturalland,seededmainlywithalfalfa(Medicagosativa)andmaize(Zeamays)forgrain.Themilkproductionpercowwasfrom3,500to4,500kgin305days,witha13.8monthperiodbetweencalvings.Therewere88.8%ofthefarmswithsubclinicalmastitiswithover20%ofprevalence.Thetuberculosisandbrucelosisprevalencewas6.8and3.3%.Therelationbetweenfreshexcretaproductionandmilkproductionwas4.7:1(freshbasis).Ascontaminantstherewerephosphatesderivedfromdetergentsindrinkingwatersourcesandinanirrigationchannel.Theyweredetectedtoointhewellssupplyingwatertothelivestockoneachfarmandwereapparentlyderivedfromfaeces.Nitrateswerefoundinwaterfromoneofthewellsandfaecalcoliformswerefoundinallofthem,derivedfromexcretaofthemilkingcattle.Therewasnostandardmanuremanagementonthecroplands.Itisconcludedthatthemethodologywasusefulforevaluatingtheproductioninthesmall-scalefarmsandtheenvironmentaleffectonthesourcesofnbsp;water.Arisingfromthestudy,sixMastertheseswereinitiated.