Dr Eva Mainau Brunsó and Elke Abbeloos
An uneventful calving is a prerequisite for a good start in life for the calf and one worry less in the critical transition period of the cow. In contrast, dystocia – difficult labour requiring assistance for calf delivery – is known to cause serious consequences, both for the dam and the calf.
An uneventful calving is a prerequisite for a good start in life for the calf and one worry less in the critical transition period of the cow. In contrast, dystocia – difficult labour requiring assistance for calf delivery – is known to cause serious consequences, both for the dam and the calf.
Dystocia is considered to be extremely painful for the cow. This has been proven by an increase in acute phase proteins, but also through some behavioural changes. But the impact of dystocia goes far beyond the pain at the moment of birth. Several studies have shown a significant negative effect of dystocia on milk production1. It has been suggested that this is a direct effect of the pain and inflammation during early transition2. The expected loss of milk is estimated at 135-165L in cows producing an average of 8000 litres. An even greater effect may be expected in higher producing herds.
Decreased milk production in dystocic cows may also be explained by a higher risk of disease3, including reproductive inflammatory disorders such as metritis and endometritis, often as a consequence of retained placenta (RP). This increased health hazard may lead to a higher risk of culling, especially in early lactation. Culling may also be due to loss of milk production.
Lastly, dystocic cows have a decreased fertility4. After dystocia, cows may have a delayed uterine involution, delayed onset of luteal activity and an abnormal progesterone profile5. Researchers have calculated this means an extra 2 to 3 days to first service, a 4 to 10% lower conception rate at first service and 6 to 12 more days to conception6.
These long-term effects show that the costs of dystocia go well beyond the initial veterinary bill. The impact on production accounts for 41% of the costs, fertility for 34% and cow and calf morbidity and mortality for 25%1.
The negative effect of dystocia on lactation performance is comparable with mastitis or lameness4.
The use of NSAIDs to limit inflammation post-parturition
Nonsteroidal anti-inflammatory drugs (NSAIDs) may help alleviate the impact of the inflammation and presumed pain associated with parturition. However, despite their relatively common use by veterinary surgeons, only a few published studies have specifically focused on the potential benefits of NSAID therapy around parturition.
The effect of a 3-day flunixin treatment after calving was evaluated by the University of Arizona7. The authors concluded that, flunixin treatment provided no significant overall benefit. In another study of over 1200 dairy cows8, flunixin meglumine was administered 2 hours after calving with a repeat injection some 24 hours later. Again, no significant benefit of treatment was found for health or milk production. However, cows treated with flunixin showed a significant increase in both the risk of retained placenta and the risk of developing metritis.
Carprofen was investigated on 40 cows9, where it was given within 6 hours after parturition. The study found no significant difference in time of placenta expulsion or incidence of clinical disease. However, more animals from the analgesia group were observed eating in the first hours after parturition. The total lactation yield was significantly higher in analgesic heifers (11,200 L compared to 8,600 L in the control animals). The author suggests that these animals may have benefited by eating more during the first days after calving thanks to pain control, thereby reducing the risk of metabolic problems and increasing milk production. However, this benefit was not reflected in fertility: since the carprofen-treated cows had a significant increased time from calving to conception.
A study of 447 cows and heifers looked at the use of ketoprofen at calving. They noticed a tendency to reduce the risk of retained placenta10. Ketoprofen was given immediately after calving and again 24 hours later. There was no impact on other measures of uterine or reproductive health nor on milk yield.
The effect of meloxicam on the risk of retained membranes was investigated in a study, performed at a large commercial dairy farm in Canada11. 235 cows and heifers received meloxicam as soon as possible after calving, while 227 animals were left untreated. No impact of treatment on the risk of retained placenta was detected, giving confidence to the safety of the drug at this application.
The effect of meloxicam in animals that were either unassisted or had an easy manual pull was investigated by researchers at the University of Barcelona12. Treatment with meloxicam or placebo was randomly administered 3 hours after calving to 60 heifers and cows from a commercial dairy farm.
The heifers given meloxicam showed greater activity than the placebo animals in the days after calving.
A third meloxicam study investigated its effect in 103 dairy cows following an assisted calving13. Although the treatment (meloxicam or placebo) was administered quite late after calving (24 hours), Meloxicam-treated cows spent one hour more at the feed bunk and had more frequent visits to the feed bunk in the first day of lactation than controls (see Figures 1 & 2). There was no effect on dry matter intake, but this study was performed in an environment with very low competition, as every animal had its own dedicated spot at the feed bunk. When cows suffering from pain have to compete with more dominant cows, they might not ingest the amount of energy required.
Conclusion
Dystocia is not only painful, it is also associated with loss of milk production, impaired fertility and increased risk of culling.
Various studies have reported that short-term NSAID treatment of cows around calving is likely to be of value in improving the health and welfare of cattle and can therefore be recommended. NSAIDs with effective analgesic properties such as meloxicam may provide some behavioural benefits around calving and improve animal well-being, as indicated through changes in feeding and resting behaviour.
