1 There is no proof that tertiary hypothyroidism occurs in the dog...primarily because there is no reliable assay for measuring circulating TRH (nor TSH). 2  Thus, the possibility is there...and clinical signs and histological appearance of the thyroid would parallel those described for secondary hypothyroidism.
Rats are very easy to breed. In fact, many people end up with unplanned baby rats! Rats can reach sexual maturity at 5 weeks of age, so the sexes should be separated at this age.Rats donât recognize incest, so brothers and sisters and even mothers and sons must be separated.ats are very easy to breed. In fact, many people end up with unplanned baby rats! Rats can reach sexual maturity at 5 weeks of age, so the sexes should be separated at this age. Rats donât recognize incest, so brothers and sisters and even mothers and sons must be separated.
Life Expectancy. From birth to adult, rats take about three weeks to mature and begin fending for themselves. The rodents reach sexual maturity in about five weeks and begin mating soon after to produce the next generation to start the rat life cycle over again. Life expectancy for rats is about two to three years.