Of calves that become sick at a young age, more than 50% experience digestive problems (including diarrhoea)1, with these problems most often occurring in the calf's 2nd week of life2. This not only leads to short-term damage, such as dropout1 and reduced growth2,3, but can also lead to long-term damage4. Growth and development are important for a calf to develop into a good dairy cow. In addition, diarrhoea can cause stress and pain5,6 which is undesirable in terms of animal welfare. Besides the possible cost of treatment, calf diarrhoea also has economic consequences later in life4: reduced milk yield in the first lactation and reduced fertility3.
Diarrhoea
Diarrhoea can occur under the influence of various factors, from housing and hygiene to nutrition, stress and reduced immunity. However, calf diarrhoea at a young age often involves a combination of several factors4. In most cases, diarrhoea starts with the ingestion of one or more pathogens, such as a bacterium or virus. In the intestines, these pathogens attack the villi in the intestinal wall. This reduces the intestinal surface area, allowing less fluid to be absorbed from the intestines. On top of this, the pathogens also interfere with the transport of electrolytes and fluids through the intestinal wall. This results in a watery stool, which in addition to fluid loss is accompanied by additional electrolyte loss, which is observed externally as diarrhoea4. This decreases the calf's vitality and the calf becomes weaker, dehydrated and more susceptible to other diseases7.
If infectious diarrhoea is suspected, treatment with an antibiotic in accordance with the farm treatment plan may be necessary in severe cases. Besides the importance of reducing the use of antibiotics in view of antibiotic resistance, the use of antibiotics in young calves also has the disadvantage of killing beneficial bacteria in the developing intestinal flora in addition to harmful bacteria4. This can upset the balance of bacteria present in the gut8,9, which can lead to long-term negative effects10.
Colostrum
Colostrum, the first milk produced after calving, of good quality contains immunoglobulins (IgG), which are very important for the calf to acquire initial resistance. However, in addition to this IgG, colostrum contains many other substances that play a role in defending resistance4. One of these substances is lactoferrin. This is a protein that has been shown to prevent bacterial growth, which is related to its ability to bind iron that bacteria need for growth11. Another example is lactoperoxidase, an enzyme that can be found in colostrum, which has been shown to prevent bacterial development11. A third example is lysozyme, an enzyme that feeds on the cell walls of bacteria, killing them11. Furthermore, colostrum contains substances such as IGF-1, which stimulate gut growth and development4.
Providing colostrum after the 1st day of life can have beneficial effects for the calf. For example, research shows that providing colostrum for 14 days increased daily growth and reduced the risk of diarrhoea12,13. Which substances are responsible for this is still under investigation. Besides the previously mentioned substances, IgG may also play a role here, because even though it can no longer be absorbed by the gut at that point, it still has a protective function in the gastrointestinal tract4.
However, this does show that colostrum is a versatile natural product that offers the necessary potential for further research. After all, you only get one chance to give a calf a good start.
Source
1 Urie et al. (2018). Preweaned heifer management on US dairy operations: Part V. Factors associated with morbidity and mortality in preweaned dairy heifer calves. Journal of Dairy Science 101, 9229-9244.
2 Bartels et al. (2010). Prevalence, prediction and risk factors of enteropathogens in normal and non-normal faeces of young Dutch dairy calves. Preventive Veterinary Medicine 93, 162-169.
3 Abuelo et al. (2021). Effect of preweaning disease on the reproductive performance and first-lactation milk production in a large dairy herd. Journal of Dairy Science 104, 7008-7017.
4 Carter et al. (2021). A narrative review on the unexplored potential of colostrum as a preventive treatment and therapy for diarrhea in neonatal dairy calves. Animals 11, 2221.
5 Constable (2009). Treatment of calf diarrhea: antimicrobial and ancillary treatments. Veterinary Clinics: Food Animal Practice 25, 101-120.
6 Hulbert & Moisá (2016). Stress, immunity, and the management of calves. Journal of Dairy Science 99, 3199-3216.
7 Sjoers (2023). Onderzoek: kan biest antibiotica vervangen bij diarree? www.melkveebedrijf.nl, 7 december 2023.
8 Oultram et al. (2015). Effects of antibiotics (oxytetracycline, florfenicol or tulathromycin) on neonatal calves’ faecal microbial diversity. Veterinary Record 117, 598.
9 Van Vleck Pereira et al. (2016). Ingestion of milk containing very low concentration of antimicrobials: longitudinal effect on fecal microbiota composition in preweaned calves. PLoS ONE 11, e0147525.
10 Becattine et al. (2016). Antibiotic-induced changes in the intestinal microbiota and disease. Trends in Molecular Medicine 22, 458-478.
11 Pakkanen & Aalto (1997). Growth factors and antimicrobial factors of bovine colostrum. International Dairy Journal 7, 285-297.
12 Kargar et al. (2020). Extended colostrum feeding for 2 weeks improves growth performance and reduces the susceptibility to diarrhea and pneumonia in neonatal Holstein dairy calves. Journal of Dairy Science 103, 8130-8142.
13 Berge et al. (2009). Targeting therapy to minimize antimicrobial use in preweaned calves: effects on health, growth, and treatment costs. Journal of Dairy Science 92, 4707-4714.
