Thank you FancyChookLady for the sympathy. It has been a roller-coaster ride to say the least but I'm getting proficient at handling the little backyard flock
Coryza is definitely a head cold with the watery eyes/nostrils and bronchitis type of condition. What our Silkie had was the wheezing, coughing, head shaking, labored breathing like last year and because I know to take her immediately to the vet she never got the full spectrum of other associated CRD symptoms and I always take a poop sample with me to the vet so he can have ammunition for a more trusted diagnosis. I trust the vet knew what he was doing in eliminating the obvious to diagnose Mycoplasma plus he had worked in the poultry industry and currently treats birds in his practice as well as dogs/cats/exotics.
I was having other smaller problems throughout the year that coincidentally can be linked to latent MG/MS like diminished egg production, stress during laying (our sick Silkie hasn't once cried about laying her eggs this past week whereas she would constantly complain about laying her eggs). She now calmly quietly sits in a nestbox to lay an egg and it is so refreshing not hearing her stressed out. When she had a full crop and we picked her up in the show judge's hold she would complain if the crop pressed into her chest and now there is no obvious discomfort. We suspect severe molts that took a stressful toll on our latent MS/MG flock was attributed to the disease. Explanations are always easier in hind-sight when you can put a finger on a cause.
USA flocks are estimated about 98% infected with CRD. With the UK, Europe, and Asia successfully using Denagard as a preventative, it sounds wise to have the same regimen in the U.S. I was skeptical and so was the vet about using on a regular basis. But after a lot of research on tiamulin which is Denagard's semi-antibiotic ingredient and effective on chickens/turkeys for the control of CRD symptoms and that there is 0-days egg withdrawal, and only 2-days meat withdrawal I have accepted it as safer than say an antibiotic like Tylan which recommends up to 14 days egg withdrawal and much longer for meat. The vet said the U.K. is well-known for their knowledge on backyard chicken care and have more sources for treating poultry than USA backyarders.
Last year I don't think my vet knew I was raising chickens more for pets and not utility and probably thought I knew more about poultry than I really did. But he is taking a more personal approach now. He and I are learning from each other as we go along. People I've referred really like him. My raising a first-time backyard flock is like raising a first child - the first one is always the experiment we learn on.
I don't know a whole lot about VRE except what I've read and it doesn't fit my girl's problems. Also, we treat for lice/mites monthly - both chickens and the coop using organic Poultry Protector which can be used as often as needed without harmful side effects. Worming continues being effective with Ivermectin and will switch to another brand/type when Iver is used up. The only ammonia build-up that could possibly occur would be in the nestboxes and those are cleaned daily with fresh straw and we installed plexiglass bottoms several months ago to avoid moisure/poop ammonia soaking into wood boxes. Our coop has 3 open wire walls along the sides and 4 open wire walls below and the only secluded area for ammonia would be in nestboxes and those are maintained daily - each one is spacious at 16x16 inches by 2-1/2 feet tall. If anything, our design has too much ventilation. Plus our girls are open-range hens and not cooped or penned all day.
CRD is so easily transmitted to a flock - it can be picked up from visiting wild birds, trips to bird shows, in pet shops, on the shoes of other visiting chicken owners who aren't aware they have infected birds, county fairs, 4H events, livestock auctions, importing new hens onto the property - just a myriad of ways so it's impossible to avoid contact. Every USA flock eventually will get exposed to MG/MS CRD in any number of ways. Some birds get exposed and are carriers for life but never ever manifest outward symptoms. Other birds have low immunity to the disease and any kind of stress has the potential to trigger an outbreak in the bird. Other birds mysteriously keel over dead suddenly without ever exhibiting any outward symptoms. And like so many chicken diseases there is no "cure" - only managed or preventative treatment. The usual good diet, vitamin supplementation, worming/lice/mite preventative health maintenance all contribute to helping CRD carriers to stay immune to an outbreak but things like molting, broodiness, or weather extremes are beyond a bird's or your control so extra watchful care is needed at those times. And certainly Denagard during those times of stress for just 3-5 days once a month will help keep up immunity. And the eggs don't have to be withdrawn unless you really want to.
The vet said the entire flock should be treated with Tylan at the time of a hen's outbreak so that the other birds' immune systems can fight off coming down with symptoms. So far the treatment has worked at keeping the others immune enough that they even resumed egg-laying in the dead cold of our winter here even during the shortest days of our year. With this new egg-laying development I can only further assume that Mycoplasma was interfering with their egg production and that treatment has stimulated a boost in their health.
As per my usual anxious whirlwind research and vet's input along with wonderful BYC post inputs I am comfortable with the Denagard regimen unless someone has additional insight that hasn't been addressed yet. Over-medicating a healthy flock was my paramount concern regarding Denagard use. But since I know my flock are CRD carriers conducting monthly treatments are no longer an issue for me. Again I thank everyone's input stimulating me to do my research and get my vet on-board.
and at recognizing and identifying issues of serious vs no worries.
