As soon as the testicles have desended I believe, which happens around 6 months, or earlier, I think. However, unless a female is in heat she cannot get pregnant. Females generally have their first heat between 6 & 12 months of age though. So a 5 & 7 month old pair is very risky. That is plenty old enough to get spayed & neutered even for the most conservative vet or owner.
A sirloin roast of 8- to 12-lbs will take 16-20 minutes for rare, 20-22 for medium rare, 23-25 for medium, and 26-30 for well done. A boneless top round, by contrast, will take 28-30 minutes for rare, 30-33 for medium rare, 34-38 for medium, and 40-45 for well done.If you roast at 325Â°F (160Â°C), subtract 2 minutes or so per pound. If the roast is refrigerated just before going into the oven, add 2 or 3 minutes per pound.ow long and at what temperature should I cook a beef roast in the oven? Roasting is a great cooking method for a large, tender cut of beef  such as a rib or sirloin roast.
Pour 1/2 cup of water on top and then close the crock pot tightly. Cook the beef roast on high for between four and six hours, depending upon the size of the roast and the degree of doneness you desire such as medium or medium well. Check the roast regularly until it meets your expectations.eason-All salt and 1 tsp. seasoned pepper. Cut the roast, if necessary, to make certain it will fit into the Crock-Pot. Layer the meat as little as possible to avoid lengthening the time required for cooking. Place 1/2 cup of water in the bottom on the Crock-Pot. Turn on the Crock-Pot and set it at high.