Can a cow be tertiary level consumer?

Yes, a cow can be a tertiary level consumer. Cows are herbivores and they feed on plants. The plants are primary producers and the animals that feed on plants are primary consumers. The animals that feed on primary consumers are secondary consumers. The animals that feed on secondary consumers are tertiary consumers. Cows can feed on secondary consumers like insects and they can also be fed with meat and fish meal which makes them tertiary level consumers.