Dystocia and Difficult Calvings: A Perspective from Dam and Calf (Part 1)

By: Betsy Hicks (Dairy Specialist, South Central New York Dairy & Field Crops Team) & Casey Havekes (Dairy Specialist, North Country Regional Ag Team)

Dystocia is defined as an abnormal or difficult time during birth, at any stage of labor. A 2007 National Animal Health Monitoring System (NAHMS) study of calf loss in North America showed that 15.9% of calves died before weaning, and 8.1% of these deaths were from problems during calving and in the first 48 hours of life. We know that difficult calvings are hard on the dam, but from this we can infer that difficult calvings also negatively impact the calf. Calf vitality can be defined as the capacity to live and grow with physical and mental energy and strength, and we know that the physiology and behavior of a newborn calf is impacted by low vitality. It is estimated that dystocia has a cost of $400 million to the dairy and beef industries in the US annually, with the costs including losing the dam and/or calf, dams being culled earlier, producing less milk and rebreeding back more slowly, as well as calves being more susceptible to disease and growing more slowly. In this 2-part series, we will discuss dystocia from the dam's perspective in Part 1, and from the calf's perspective in Part 2. The information shared below was originally shared as part of Cornell Cooperative Extension's Critical Calf Care series. You can find links to the recordings by clicking here, and supplemental materials by clicking here. 

Dystocia can occur as a failure in any one or more of the three main components of calving - expulsive forces, birth canal adequacy, or fetal size and positioning. Causes for dystocia can be broken up into three main categories - proximal causes (things that present themselves at calving), intermediate causes (things leading up to calving) and ultimate causes (the main reason for dystocia) (Mee 2008). Attributes of a difficult calving might present as a uterine torsion, abnormal position of the calf, or a disproportion of the calf to the birth canal. Intermediate causes can be diagnosed as longer gestation length, nutritional causes such as hypocalcemia or stress around calving. Ultimate causes can be attributed to gender of the fetus, multiple fetuses, or fetal abnormality, as well as parity, breed of sire or dam, season, nutrition of dam, region, disease presence, history and interactions between all causes. The most common type of dystocia seen is fetal size and positioning, with the most important risk factor for dystocia being calf birthweight. Birthweight can be influenced by many of the ultimate causes formerly mentioned.

To help identify when the dam may be in need of help and may be experiencing dystocia, it is important to know the three stages of parturition. Stage 1 involves changes that may or may not be visual cues to an observer. The cervix starts to dilate 4-24 hours before birth, and pelvic muscles around the tailhead start to loosen. The cow may have increased activity, and mucus may be present. Stage 2 is what people normally think of the calving process - first the water bag and amniotic sac appear, then the calf's two front feet and a nose should appear. The dam should be making visible progress every 15-20 minutes, and 1-2 hours after the start of Stage 2, the calf should be born. Stage 3 includes the expulsion of the placenta, which involves contractions and should occur 4-24 hours after the birth of the calf. Identifying which stage the cow is in may give cues as to what issue a cow may be facing during labor. Each farm should have specific protocols for timeframes to check for problems with calving, and how to give assistance to the dam, if needed.

If assistance is needed, there are a few things to keep in mind. First, the person assisting the birth should assess the problem. Is the calf positioned correctly? Is the cervix adequately stretched? Is the uterus twisted or normal? Is the calf appropriately sized to fit through the birth canal? Assuming these questions are answered, likely the birth can be assisted with minimal issue. If they aren't, or the answers aren't clear, a call to the veterinarian is never a bad idea. If assistance is given, remembering some key things will ensure the best outcome for both the calf and dam. Cleanliness, proper chain placement on the calf's legs, lubrication, proper force without using too much force, and pulling during contractions are all important factors to keep in mind when assisting a birth. Figure 1 shows the proper chain placement on a calf's legs to ensure minimal stress to the calf when being pulled (illustration courtesy of Alabama Extension)

Figure 1. Proper chain placement on a calf's legs.

Retaining records on all births is recommended, but especially so for dystocia births. These records can be used to give prioritized care to both dam and calf after the birth. Things to note in records include: cow ID, person assisting, date, calving ease score, calf ID, results, and notes on dam and calf. For more information on record keeping, please refer to Episode 3 of Critical Calf Care (click here to access the recording).

According to 2007 NAHMS data, severe dystocia impacts 6.8% of heifers and 3.5% of cows, and mild dystocia impacts 11.8% of heifers and 7.3% of cows. With that in mind, we know dystocia and difficult calvings are inevitable; however, understanding the stages of parturition and being prepared for recognizing signs of distress during calving are critical components of helping both the dam and calf through a difficult birth. Part 2 will discuss the impact of dystocia on the newborn calf and strategies for the producer to use to give the best quality of care to dystocia calves. If you have dystocia problems on your farm, please reach out to one of us (Betsy Hicks: bjh246@cornell.edu; 607-391-2673 / Casey Havekes: cdh238@cornell.edu; 315-955-2059) and we can help you troubleshoot this challenging area.