Times are changing and with change comes new ways we should look at our chronic pens in feedlots. Each decision should be based on sound medical judgment, economics and the possibility for salvage. All these factors must be weighed on each individual case to determine the course of action.
There are no cookbook answers to handle these cases. Over time, protocols can be established for certain types of chronics, in co-operation with your feedlot veterinarian.
Chronics are generally lumped into several large categories. Respiratory and arthritic calves form the largest groups. Traumatic, bullers and other lameness together with all the miscellaneous conditions form the other broad categories.
I think it is important with all chronics to assess improvement or deterioration and the best objective measurement we have of this is weight loss/gain. If weight is taken on an accurate scale every two weeks, it gives us the answer we need. With most conditions in the feedlot, a third treatment is generally the maximum I recommend. If the powerful arsenal of medication we have at our disposal has not rid the calf of the infection or problem by then, it is not going to happen.
In the case of respiratory chronics, the infection has either been controlled or walled off and the permanent lung damage is the result. These animals will always have reduced lung capacity and an increased respiratory rate, especially if they are stressed. With time and convalescence they can gain some weight otherwise they should be humanely put down or shipped for salvage once all drug withdrawals have been met. To go on continually treating a lot of these cases is futile and autopsies revealing multiple abscesses and large areas of solidified lungs help us understand why this is so.
With prophylactic use of antibiotics in the feedlot respiratory chronics have taken a secondary position to chronics from arthritis. Badly infected joints often form histophilus (the old hemophilus), or mycoplasma infections make up the vast majority of arthritic conditions. Again if three treatments have not corrected the situation it is no use persisting. Painkillers can be used but they only provide temporary relief. In some cases convalescence for long periods will see conditions improve and cattle gain weight. Septic arthritis involving the lowest joint (under the hoof) could resolve from claw amputations (surgery) by your veterinarian.
Again, each case should be viewed on its individual merits and economics. The more feedlot animals which can be purchased having received their initial vaccinations for histophilus and respiratory pathogens, the more we will minimize the incidence of these chronic conditions. With mycoplasma there still is no vaccine available yet.
Other lameness should be examined individually. Sole abscesses can be treated whereas blown stifle joints or back problems should probably live out their days in the chronic pen. If competition and distance to feed and water are minimized, many of these animals will gain weight and reach a slaughterable condition. All they need is time and TLC (tender loving care).
In the feedlot one must also consider the disruption to the home pen dynamics if they are returned. This is very evident with bullers or sweet asses. Reintroduction is very hard unless processing or sorting is already happening and disrupting the pen. These animals cause tremendous weight loss to other animals in the pen, let alone the potential sores or back problems they themselves develop from being ridden. They are an economic hardship on the feedlot and are best living out their days in the chronic pen until shipped. All feedlots have some but if the incidence gets too high your veterinarian can explore causes such as implant technique (crushing), pen design or size, feed, hermaphrodites or a myriad of other possibilities.
Traumatic events can happen in the feedlot with the large numbers being handled. I like to document these to explore if there is a weak link in design or handling or in rare cases staff care. Accidents are not always preventable and we know that hyper cattle have an increased likelihood of injury. Avoiding buying these types might be another plan to prevent these injuries. Each case is different and attention as quick as possible may minimize long-aterm convalescence with regards to deep cuts, potential broken limbs or cuts exposing bone and/ or joints. The feedlot veterinarian may also advise emergency slaughter before antibiotics are pumped into hopeless cases.
Remember to assess all chronics individually using time and convalescence to your advantage. Use weight gain to monitor improvement or deterioration. Have your feedlot veterinarian determine if there is any preventive to avoid similar cases in the future. The chronic pen will always be a necessary part of any large feedlot and requires attention.
Roy Lewis is a large-animal veterinarian practising at the Westlock Veterinary Centre. His main interests are bovine reproduction and herd health.