TL;DR
These 2 hikvision variants ( hikvision-ds7608 and hikvision-ds) do not use the same MIB file.

################### enterprise 50001 ######################
############## hikvision-ds7608 NOTE: the trailing "." ##############
$ snmpwalk -v2c -c hikvision-ds7608 -M mibs/hikvision:mibs -m HIK-DEVICE-MIB hikvision-ds7608:1161 .
SNMPv2-SMI::mib-2.1.1.0 = STRING: "Hikvision company products"
SNMPv2-SMI::mib-2.1.2.0 = OID: SNMPv2-SMI::enterprises.50001
SNMPv2-SMI::mib-2.1.3.0 = Timeticks: (85447143) 9 days, 21:21:11.43
SNMPv2-SMI::mib-2.1.4.0 = ""
SNMPv2-SMI::mib-2.1.5.0 = ""
SNMPv2-SMI::mib-2.1.6.0 = ""
SNMPv2-SMI::mib-2.1.7.0 = INTEGER: 72
SNMPv2-SMI::mib-2.1.8.0 = Timeticks: (0) 0:00:00.00
SNMPv2-SMI::mib-2.2.1.0 = INTEGER: 2
SNMPv2-SMI::enterprises.50001.1.1.0 = IpAddress: 192.168.80.94
SNMPv2-SMI::enterprises.50001.1.2.0 = INTEGER: 8000
SNMPv2-SMI::enterprises.50001.1.3.0 = STRING: "0820160719AARR624053979WCVU"
SNMPv2-SMI::enterprises.50001.1.100.0 = INTEGER: 2
SNMPv2-SMI::enterprises.50001.1.101.0 = INTEGER: 200
SNMPv2-SMI::enterprises.50001.1.102.0 = INTEGER: 1
SNMPv2-SMI::enterprises.50001.1.103.0 = INTEGER: 255
SNMPv2-SMI::enterprises.50001.1.104.0 = INTEGER: 255
SNMPv2-SMI::enterprises.50001.1.105.0 = INTEGER: 0
SNMPv2-SMI::enterprises.50001.1.106.0 = ""
SNMPv2-SMI::enterprises.50001.1.110.0 = ""
SNMPv2-SMI::enterprises.50001.1.200.0 = INTEGER: 1
SNMPv2-SMI::enterprises.50001.1.201.0 = STRING: "1000MHZ"
SNMPv2-SMI::enterprises.50001.1.220.0 = INTEGER: 169
SNMPv2-SMI::enterprises.50001.1.221.0 = INTEGER: 5
SNMPv2-SMI::enterprises.50001.1.230.0 = INTEGER: 1
SNMPv2-SMI::enterprises.50001.1.231.0 = INTEGER: 1
SNMPv2-SMI::enterprises.50001.1.240.0 = INTEGER: 2
SNMPv2-SMI::enterprises.50001.1.241.1.1.1.0 = INTEGER: 1
SNMPv2-SMI::enterprises.50001.1.241.1.1.2.0 = INTEGER: 2
SNMPv2-SMI::enterprises.50001.1.241.1.2.1.0 = STRING: "lable01"
SNMPv2-SMI::enterprises.50001.1.241.1.2.2.0 = STRING: "lable02"
SNMPv2-SMI::enterprises.50001.1.241.1.3.1.0 = INTEGER: 0
SNMPv2-SMI::enterprises.50001.1.241.1.3.2.0 = INTEGER: 0
SNMPv2-SMI::enterprises.50001.1.241.1.4.1.0 = INTEGER: 2715648
SNMPv2-SMI::enterprises.50001.1.241.1.4.2.0 = INTEGER: 3813376
SNMPv2-SMI::enterprises.50001.1.241.1.5.1.0 = INTEGER: 3815447
SNMPv2-SMI::enterprises.50001.1.241.1.5.2.0 = INTEGER: 3815447
SNMPv2-SMI::enterprises.50001.1.241.1.5.2.0 = No more variables left in this MIB View (It is past the end of the MIB tree)

############## hikvision-ds WITHOUT "." ##############
$ snmpwalk -v2c -c hikvision-ds -M mibs/hikvision:mibs -m HIK-DEVICE-MIB hikvision-ds:1161 
SNMPv2-SMI::mib-2 = No Such Instance currently exists at this OID

################### enterprise 39165 ######################
############## hikvision-ds NOTE: the trailing "." ##############
$ snmpwalk -v2c -c hikvision-ds -M mibs/hikvision:mibs -m HIK-DEVICE-MIB hikvision-ds:1161 .
HIK-DEVICE-MIB::deviceType.0 = STRING: "DS-2CD2185FWD-I"
HIK-DEVICE-MIB::hardwVersion.0 = STRING: "0"
HIK-DEVICE-MIB::softwVersion.0 = STRING: "V5.5.3 build 171025"
HIK-DEVICE-MIB::macAddr.0 = STRING: "b4-a3-82-35-9a-0c"
HIK-DEVICE-MIB::deviceID.0 = STRING: "1"
HIK-DEVICE-MIB::manufacturer.0 = STRING: "Hikvision"
HIK-DEVICE-MIB::cpuPercent.0 = STRING: "15 PERCENT"
HIK-DEVICE-MIB::diskSize.0 = STRING: "0.0 GB"
HIK-DEVICE-MIB::diskPercent.0 = STRING: "0 PERCENT"
HIK-DEVICE-MIB::memSize.0 = STRING: "512 MB"
HIK-DEVICE-MIB::memUsed.0 = STRING: "83 PERCENT"
HIK-DEVICE-MIB::restartDev.0 = INTEGER: 0
HIK-DEVICE-MIB::dynIpAddr.0 = IpAddress: 172.16.1.132
HIK-DEVICE-MIB::dynNetMask.0 = IpAddress: 255.255.255.192
HIK-DEVICE-MIB::dynGateway.0 = IpAddress: 172.16.1.129
HIK-DEVICE-MIB::staticIpAddr.0 = IpAddress: 0.0.0.0
HIK-DEVICE-MIB::staticNetMask.0 = IpAddress: 0.0.0.0
HIK-DEVICE-MIB::staticGateway.0 = IpAddress: 0.0.0.0
HIK-DEVICE-MIB::sysTime.0 = STRING: "2019-03-13 20:51:10"
HIK-DEVICE-MIB::videoInChanNum.0 = INTEGER: 1
HIK-DEVICE-MIB::videoEncode.0 = STRING: "H.264"
HIK-DEVICE-MIB::videoNetTrans.0 = STRING: "MJPEG"
HIK-DEVICE-MIB::audioAbility.0 = INTEGER: 0
HIK-DEVICE-MIB::audioInNum.0 = INTEGER: 0
HIK-DEVICE-MIB::videoOutNum.0 = INTEGER: 0
HIK-DEVICE-MIB::clarityChanNum.0 = INTEGER: 1
HIK-DEVICE-MIB::localStorage.0 = INTEGER: 1
HIK-DEVICE-MIB::rtspPlayBack.0 = INTEGER: 1
HIK-DEVICE-MIB::netAccessType.0 = STRING: "ETHERNET"
HIK-DEVICE-MIB::alarmInChanNum.0 = INTEGER: 0
HIK-DEVICE-MIB::alarmOutChanNum.0 = INTEGER: 0
HIK-DEVICE-MIB::manageServAddr.0 = IpAddress: 0.0.0.0
HIK-DEVICE-MIB::ntpServIpAddr.0 = STRING: "192.168.1.120"
HIK-DEVICE-MIB::managePort.0 = INTEGER: 0
HIK-DEVICE-MIB::managePort.0 = No more variables left in this MIB View (It is past the end of the MIB tree)