As everyone mentioned, please take your girl to see a vet and get her spayed, or get that male neutered. Just because someone told you she can't breed doesn't mean it was true. To my knowledge, not even children's medicine is safe for dogs and cats, much less our sensitive rats. Spaying the female doesn't only prevent unwanted litters, she'll be less hormonal, the male will be a bit calmer, and lowers the likelihood of tumors in her.
If the rat is coughing, it's often very serious, because a majority of rats don't cough, they sneeze. Coughing indicates shortness of breath, or a blockage in their trachea or esophagus. Either way, both of these conditions are serious to a rat's health and require antibiotics.
I saw a thread here a while ago that feeding high amounts of proteins, especially from meats, is more likely to cause tumors in rats and shorten the overall lifespan of your rat. You can give them this stuff as treats on the side (excluding high amounts of meat). Dog food and cat food are once-in-a-while treats, if at all, raw uncooked spaghetti (with no sauce) noodles are great treats. Dog food and cat food are not appropriate for rats since there are tons of rat lab blocks out there. Dog food and cat food both contain too much protein and too much fat (it fluctuates brand by brand, but some brands have very high fat content), both of which are cancer-causing agents in rats. Rats are already susceptible to tumors, we like to lower the likelihood as much as we can. I don't know too much about bones, but I still would be cautious giving them a lot of it. It's a good enrichment item, but there are other safer enrichment alternatives.
Oxbow contains low protein, low fat and should be a staple food. This is healthy for the rats and gives them all of the nutrients they need. I always have bowls of Oxbow rat food in my cage, and then they are given veggies, very few fruits, and good-for-them table scraps daily. Corn has no nutritional value, but it can still be given as a treat and enrichment for the rats. A feed store local to me (I live in Minnesota, so we have a ton of farmers markets and feed stores everywhere lol), sells Oxbow for $14. If your feed store doesn't have it, Oxbow has a website. Petsmart and Petco carry these brands as well (at least locally to me).
Also, depending on what site(s) you read, just because they say a rat can eat everything, doesn't necessarily mean they SHOULD eat everything. Rats have longer lifespans in captivity because we improve their diet, give them vet care, protect them from predators, and smother them in love. In the wild, rats live fast and die young. In captivity, they live lazily and are spoiled with good food. Wild rats live to be less than a year old, whereas pet rats can live up to three years old.
On the side, if you have a parrot or other type of bird, please avoid feeding an all-seed based diet. That leads to nutritional deficits as well. I have a green cheek conure and he's on a pellet diet, with veggies, fruits, and whatever else he can eat on the side. I don't know too much about chickens.