Is colostrum part of your calving season kit?
By Michael Nagorske, DVM
As calving season approaches, it’s important to prepare for the many nuances it brings, from long hours, sleepless nights, and cold temperatures to the equipment needed to complete the job.
I think we can all agree there’s much that goes into this season and that many prepare the proverbial calving kit. Typical kit contents no doubt include a calf puller, and ob chains, lube, and sleeves. However, one component we need not forget and, in a sense, should be most important, is colostrum.
One could argue the calf puller may be more important — if you can’t get a live calf on the ground, then colostrum is useless. However, let me remind of some important things about dystocia and colostrum and then you can decide its importance.
Adequate colostrum ingestion is essential
Let’s start with transfer of passive immunity (TPI). TPI is essential for a calf because the syndesmochorial placentation does not allow for maternal antibodies to cross the placenta.1 Therein, they must rely on the maternal antibodies and bioactive factors found in colostrum to, in a sense, serve as their immune system until their own is developed. Adequate colostrum ingestion is the single most important determinant of health, survival, performance and, therein, profitability in a calf’s life.2,3,4,5,6 Studies have proven this more in dairy; however, implications on preweaning morbidity, mortality, and average daily gain have been illustrated in the beef cow-calf sector.7,8,9
It is intuitive for you to think if a calf doesn’t get enough immunity, it’s prone to increased risk for morbidity and mortality. The impacts on weight gain, however, are often forgotten. One can argue the single most important aspect of the feeder-calf business is efficient weight gain. Interestingly, as it pertains to passive transfer, Dewell et al. found calves with lower immunoglobulin (IgG) concentrations to be 3.35 kilograms (kg)/7.38 pounds (lbs) lighter at weaning.8 This difference in gain was found at a cutoff level much higher than most studies performed in dairy calves and at 27 grams (g)/liters (L).
In another study by Wittum et al., they found weight gain impacts were an indirect result of preweaning morbidity.7 In other words, passive transfer had direct impacts on morbidity both preweaning and into the feedlot phase. This, therein, had indirect effects on preweaning and feedlot growth through effects of morbidity. Specifically, morbidity in the first 28 days of life led to a 16 kg/35 lb reduction in weaning weight. For those calves experiencing a serum IgG below the 8 g/L cut-off, they were 6.4 times more prone to sickness in the first 28 days of life, 3.2 times more prone to sickness prior to weaning, and 5.4 times more prone to death prior to weaning.
If we just look at the weight gain alone: Consider a 500-pound steer bringing $220 per hundredweight (cwt). A steer that weighs 35 lbs lighter equates to a price difference of $77 in today’s market.10 Another reminder: The prevalence of failure of transfer of passive immunity (FTPI) is reported to range from 11–31 percent in United States beef herds.11 There are many risk factors for failed TPI that can be outlined in a separate article itself. For the purposes of this one, let’s look at dystocia.
Dystocia and its impact
Calving difficulty certainly has implications for lack of sleep, but there are others as we consider the animal itself, starting specifically with the calf.
While the calf puller has allowed for many saved calves, it is important to understand this tool. The most impressive ability of this device is the immense force it can exert on a calf. Pearson et al. found the median cumulative force for mechanical deliveries to be 839 lbs per minute on the average and upwards of 1,856 lbs per minute in extreme cases.12 It goes without saying, this could exert enough force to cause trauma to the calf and, indeed, has consequences. In fact, dystocia in beef calves is the most common cause of preweaning mortality, accounting for 50 percent of deaths compared to other diseases.13 As we look at peripartum deaths specifically, most are indeed attributed to acidemia and trauma.14
In these instances, we need to circle back to the importance of colostrum. Some studies have shown an association between decreased absorption of IgG and dystociainduced respiratory acidosis, hypoxia, and hypercapnia.15,16 Others have not appreciated this phenomenon with both arterial and venous blood assessments.17,18 Regardless, the evidence of acidemia and trauma alone have indirect implications on colostrum consumption; suckling reflex and increased time to standing are proven and indicative of fetal stress.18 Studies have shown anywhere from a 52–74 percent reduction in colostrum consumption in the first 12 hours after birth.18,19
Colostrum as a vital tool
Scenarios like these are where utilizing a tool such as a colostrum replacer becomes a vital part of the calving kit. In dystocia cases, replacer could be argued as a pivotal component of what goes with the calf puller and in terms of post-delivery protocols. Given the likelihood of acidemia and, thereby, decreased ability to stand and suckle, a whole-bovine-based colostrum replacer can and should be utilized. This is especially true given the essence of time and importance of the first few hours for optimal IgG absorption.
New recommendations elicited from dairy calf research now indicate a mass of 300g of IgG be provided for normal calves within the first 12 hours of life.20 While most replacers on the market are typically between 100–150g of IgG in one packet, there are new replacers obtaining upwards of 200g of IgG. Given a calf can handle upwards of 10 percent of its body weight tube-fed (80lb/40kg calf = 4L) and the fact most dystocia calves are higher birth weight, it would be indicated to tube feed a dystocia calf between 200–300g of IgG within the first hours (4 to 4.5L final mixed volume), followed by another 100–200 by 12 hours old. This also can be done by utilizing two bags of 100g IgG or 2 bags of 115g IgG tube-fed right away. If a 150g IgG bag is utilized and has a total mixed volume of 2L by itself, one could then also tube feed 2 bags of a 150g IgG presentation. It will also work to tube feed 200–300g of IgG within the first hours and, if the calf is then up sucking within 12 hours, and the cow has good udder fill and teat confirmation, it likely will not need the second feeding.
Nowadays, everything should be challenged with economics while also keeping in mind judicious and preventative use of antimicrobials
This all may seem like an overload of colostrum, but it should indeed be a standard of care given the nature of the physiological consequences. Furthermore, even with aggressive colostrum intervention, these calves still pose risk for failed TPI and already carry a 2.4 times greater risk for disease and treatment in the first months of life.21
Nowadays, everything should be challenged with economics while also keeping in mind judicious and preventative use of antimicrobials. Given the stakes involved with inadequate passive transfer when considering morbidity, mortality, and average daily gain, it should be evident interventions involving colostrum feedings can provide a return on the investment, and that the use of colostrum replacer can, indeed, fit in a post-dystocia protocol.
