You can use unlicensed lay persons for the performance of non-technical duties such as calling in prescriptions (other than for controlled substances), as long as those duties don't require a knowledge of veterinary science.  You are ultimately responsible for knowing whether those persons are qualified by training or experience to perform the duties adequately.

Section 6810, paragraph 4, of the Pharmacy Law (at http://www.op.nysed.gov/prof/pharm/article137.htm) says:

a.  Oral prescriptions for controlled substances shall be filled pursuant to article thirty-three of the public health law. A pharmacist may fill an oral prescription for a drug, other than a controlled substance, made by a practitioner legally authorized to prescribe drugs. An oral authorization for the refill of a prescription, other than a prescription for a controlled substance, may be made by a practitioner legally authorized to prescribe drugs. The pharmacist receiving such oral authorization for the refill of a prescription shall write on the reverse side of the original prescription the date, time, and name of the practitioner authorizing the refill of the prescription. An oral prescription or an oral authorization for the refill of a prescription for the drug, other than a controlled substance, may be communicated by an employee of the prescribing practitioner; provided, however, the pharmacist shall:

  1. contemporaneously reduce such prescription to writing;
  2. dispense the substance in conformity with the labeling requirements applicable to a written prescription; and
  3. make a good faith effort to verify the employee's identity if the employee is unknown to the pharmacist.