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  <xs:element id="pets_AccruedMerchandiseCreditsAndRewardsCurrent" abstract="false" name="AccruedMerchandiseCreditsAndRewardsCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pets_AccruedPropertyPlantAndEquipmentCurrent" abstract="false" name="AccruedPropertyPlantAndEquipmentCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pets_AccruedSalesReturnsAndAllowancesCurrent" abstract="false" name="AccruedSalesReturnsAndAllowancesCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pets_DeferredTaxAssetsDeferredExpenseCapitalizedResearchAndDevelopmentCosts" abstract="false" name="DeferredTaxAssetsDeferredExpenseCapitalizedResearchAndDevelopmentCosts" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pets_DeferredTaxAssetsLeaseLiabilities" abstract="false" name="DeferredTaxAssetsLeaseLiabilities" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pets_DeferredTaxLiabilitiesChangeInAccountingMethod" abstract="false" name="DeferredTaxLiabilitiesChangeInAccountingMethod" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pets_OperatingLossCarryforwardAxis" abstract="true" name="OperatingLossCarryforwardAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="pets_OperatingLossCarryforwardDomain" abstract="true" name="OperatingLossCarryforwardDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pets_DeferredTaxAssetIsRecordedMember" abstract="true" name="DeferredTaxAssetIsRecordedMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pets_EffectiveIncomeTaxRateReconciliationDeferredTaxAssetAdjustment" abstract="false" name="EffectiveIncomeTaxRateReconciliationDeferredTaxAssetAdjustment" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pets_EffectiveIncomeTaxRateReconciliationCompensationOfCoveredPeopleLimitDeductionAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationCompensationOfCoveredPeopleLimitDeductionAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pets_SEC382LimitedUtilizationMember" abstract="true" name="SEC382LimitedUtilizationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pets_OperatingLossCarryforwardsSubjectToLimitations" abstract="false" name="OperatingLossCarryforwardsSubjectToLimitations" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pets_OperatingLossCarryforwardsNotSubjectToLimitations" abstract="false" name="OperatingLossCarryforwardsNotSubjectToLimitations" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pets_DisallowedBusinessInterestExpenseCarryover" abstract="false" name="DisallowedBusinessInterestExpenseCarryover" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pets_EffectiveIncomeTaxRateReconciliationTaxesPayableAdjustmentsAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationTaxesPayableAdjustmentsAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pets_EffectiveIncomeTaxRateReconciliationTaxesPayableAdjustmentsPercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationTaxesPayableAdjustmentsPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="pets_PreferredStockVotesPerShare" abstract="false" name="PreferredStockVotesPerShare" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="pets_BeneficialOwnershipThresholdPercentage" abstract="false" name="BeneficialOwnershipThresholdPercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="pets_ClassOfWarrantOrRightPercentOfCommonStockExerciseThreshold" abstract="false" name="ClassOfWarrantOrRightPercentOfCommonStockExerciseThreshold" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="pets_ClassOfWarrantOrRightMarketValuePurchasePriceRate" abstract="false" name="ClassOfWarrantOrRightMarketValuePurchasePriceRate" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="pets_TwoThousandFifteenOutsideDirectorEquityCompensationRestrictedStockPlanMember" abstract="true" name="TwoThousandFifteenOutsideDirectorEquityCompensationRestrictedStockPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pets_The2016EmployeeEquityCompensationRestrictedStockPlanMember" abstract="true" name="The2016EmployeeEquityCompensationRestrictedStockPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pets_A2022EmployeePlanMember" abstract="true" name="A2022EmployeePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pets_A2024OmnibusIncentivePlanMember" abstract="true" name="A2024OmnibusIncentivePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pets_A2024InducementPlanMember" abstract="true" name="A2024InducementPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pets_EmployeeAndDirectorEquityCompensationPlanMember" abstract="true" name="EmployeeAndDirectorEquityCompensationPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pets_PerformanceRestrictedStockMember" abstract="true" name="PerformanceRestrictedStockMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pets_NonvestedRestrictedStockMember" abstract="true" name="NonvestedRestrictedStockMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pets_FormerChiefFinancialOfficerMember" abstract="true" name="FormerChiefFinancialOfficerMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pets_ShareBasedPaymentArrangementTrancheFourMember" abstract="true" name="ShareBasedPaymentArrangementTrancheFourMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pets_FiscalYear2023Member" abstract="true" name="FiscalYear2023Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pets_FiscalYear2024Member" abstract="true" name="FiscalYear2024Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pets_PercentageOfAutomaticIncreaseInSharesAvailableForIssuance" abstract="false" name="PercentageOfAutomaticIncreaseInSharesAvailableForIssuance" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="pets_RestrictionPeriod" abstract="false" name="RestrictionPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="pets_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedHurdlePeriod" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedHurdlePeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="pets_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantedTotalGrantDateFairValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantedTotalGrantDateFairValue" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pets_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndIssuedInPeriodWeightedAverageGrantDateFairValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndIssuedInPeriodWeightedAverageGrantDateFairValue" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="pets_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndIssuedInPeriod" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndIssuedInPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="pets_EarningsPerShareBasicAndDilutedEPSAbstract" abstract="true" name="EarningsPerShareBasicAndDilutedEPSAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="pets_DefinedContributionPlanWithIndividualAge" abstract="false" name="DefinedContributionPlanWithIndividualAge" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="pets_RelatedPartyTransactionServicePeriod" abstract="false" name="RelatedPartyTransactionServicePeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="pets_RelatedPartyTransactionNumberOfNoticePeriodInAdvance" abstract="false" name="RelatedPartyTransactionNumberOfNoticePeriodInAdvance" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="pets_RelatedPartyTransactionAnnualAmountsOfTransactionYearOne" abstract="false" name="RelatedPartyTransactionAnnualAmountsOfTransactionYearOne" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pets_RelatedPartyTransactionAnnualAmountsOfTransactionAfterYearOne" abstract="false" name="RelatedPartyTransactionAnnualAmountsOfTransactionAfterYearOne" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pets_FormerChiefExecutiveOfficerMember" abstract="true" name="FormerChiefExecutiveOfficerMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pets_InterimChiefExecutiveOfficerAndPresidentMember" abstract="true" name="InterimChiefExecutiveOfficerAndPresidentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pets_ConsultingServicesPeriod" abstract="false" name="ConsultingServicesPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="pets_SalaryAndWageOfficerAnnualBaseSalary" abstract="false" name="SalaryAndWageOfficerAnnualBaseSalary" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pets_SupplementalUnemploymentBenefitsSalaryContributionPeriod" abstract="false" name="SupplementalUnemploymentBenefitsSalaryContributionPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="pets_SupplementalUnemploymentBenefitsCOBRAPremiumsReimbursementPeriod" abstract="false" name="SupplementalUnemploymentBenefitsCOBRAPremiumsReimbursementPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
</xs:schema>
