Westpoint Farm Vet’s Tim Potter takes a closer look at the causes of a common post-calving condition, how to treat it and – more importantly – how to prevent it
Left displaced abomasums are one of the most common reasons for surgery on UK dairy farms. Up to 90% of left displaced abomasums (LDAs) occur during the first four weeks post calving and producers should aim for fewer than three cases per 100 cows. It is possible to achieve rates of less than 1% in herds where close attention to feeding and management is paid during the three weeks prior to and the three weeks post calving. Controlling production diseases at and around calving also reduces the LDA risk.
Even with successful treatment, LDAs result in economic losses related to decreased milk production and fertility, premature culling, and cost of treatment. So prevention is key and prompt diagnosis and treatment, when it does occur, will help to reduce economic losses and the health and fertility impact on the cow.
LDAs are most often seen in high-yielding dairy cows and occur when the fourth stomach (abomasum) fills with gas, moves from its normal position on the floor of the abdomen and floats up on the left side between the body wall and rumen.
The cow’s uterus displaces the abomasum during pregnancy, so there is an increased risk of the condition immediately after calving, as the abomasum has to move back to its normal position. Disruption of the stomach’s typical pattern of contractions can also lead to a build-up of gas and cause it to displace.
A variety of different nutritional, environmental and health factors can increase the risk of LDAs. Excessive body condition around calving, difficult calvings, and twins have all been identified as risk factors. On the nutritional front, feeding highly digestible feeds or low-fibre diets can increase the likelihood of LDAs, as can production diseases including milk fever and ketosis. Signs to look out for include a drop in appetite, depression and reduced milk production. Cows can also be suffering with ketosis. If LDA is suspected, producers should call their vet. The vet will listen to the abdomen with a stethoscope for a ‘pinging’ sound, which is indicative of gas within the displaced abomasum. Rapid identification and treatment will speed up the cow’s rate of recovery and minimise milk production losses.
LDA diagnosis: will she pass the ‘ping’ test?
There are several different approaches to treating LDAs, ranging from the conservative approach of casting and rolling, where the LDA will re-occur in between 60% and 70% of cases, through to surgical correction.
The latter is often the treatment of choice for LDA because it reduces the risk of recurrence and allows better assessment of the condition of the abomasum. There are a number of different surgical approaches, including laparoscopic methods, and the technique chosen will depend on the vet. All the methods involve manipulating the abomasum back into the correct position and then stitching it in place.
However a displacement is treated, it is important to manage the cow correctly – and carefully – afterwards, to ensure the best possible recovery. Cows should be given access to good-quality forage, and concentrate feed should be restricted. It is also essential to treat any concurrent disease, such as metritis.
Prevention is always better than cure. Transition is the major risk period for LDAs, so it’s essential that cows are carefully managed during this time. The LDA risk can be reduced by achieving good rumen fill, with plenty of -quality forage, throughout this period.
Tips to reduce the risk of LDA
● Ensure cattle are not too fat (BCS >3.5) at calving
● Feed high-quality forage
● Feed a TMR, rather than large ‘slugs’ of concentrate
● Ensure there is sufficient trough space to allow easy access to the ration
● Practice good nutritional management to minimise changes and ensure smooth transition
● Prevent and promptly treat production diseases at and around calving including: milk fever, metritis, toxic mastitis, and retained cleansings
● Maximise cow comfort and minimise stress