Anyone who has cared for a mare during her pregnancy, attended a foaling, or shepherded a foal through its first weeks of life, is anxious to keep them healthy and comfortable, with the foal successfully launched on its way.
Studies have shown that stress may interfere with the proper functioning of the endocrine system, immune system, or both, resulting in impaired fetal growth and reproductive losses. The beneficial effects of bioactive proteins (marketed as LIFELINE®) on animals during the stress of pregnancy and lactation may be due to modulation of the immune system, which can reduce the negative effects associated with stressful conditions. Evidence in mice and humans indicates that inflammation interferes with the maintenance of pregnancy, fetal survival and growth, and implantation of embryos. In theory, oral bioactive proteins may improve overall well-being and reduce stress associated with pregnant and lactating mares and their foals.
The Blue Hors study took place in Denmark, with the approval of the Danish Ministry of Food, Agriculture, and Fisheries, on 26 pregnant Warmblood dressage mares, to evaluate the effect of bioactive proteins in late pregnancy and early lactation. Certain stress biomarkers were monitored at regular intervals in the mares and their foals, to assess changes.
Of the 26 mares, 13 were given a placebo, and 13 were given oral bioactive proteins at the rate of 240g per head per day in two doses, from approximately 50 days prior to foaling, until 60 days post-foaling. Some of each group were located in each of two barns, and the people dosing and recording observations knew only the color of the label, and not the content of the supplement. Both the placebo and the bioactive proteins had been tested ahead of time for palatability to ensure 100% consumption.
Behavior and health issues in both mares and foals were carefully recorded, as well as swelling of joints or limbs in the mares, and fecal consistency in foals. And at regular intervals, blood samples were taken, then coagulated and centrifuged to extract the serum (the liquid component of plasma after the blood cells and fibrins have been separated out). Levels of certain components of the serum were then measured and recorded.
Body weight was also recorded at regular intervals. Five days after foaling, the mares on bioactive proteins had been able to maintain higher body weights, and then came into line with the Placebo mares at 30 and 60 days.
Foals from mares on bioactive proteins had significantly fewer medical treatments (7.7% as compared to 30.8%) than those in the placebo group, and the supplemented mares had higher IgG levels for all testing intervals, indicating better immune status. IgG is a special type of protein that is the most common antibody found in the circulatory system, and antibodies are important in fighting disease, as they kill bacteria, viruses, and other germs.
All who have raised foals will be familiar with the IgG test on the foal administered by the veterinarian 12-18 hours after birth, and then most of the time, having the hanging bag of gamma plasma administered shortly thereafter, to raise the IgG level, and thereby the ability of the newborn to fight disease until his/her own immune system develops in the second month.
The mares on bioactive protein and their foals had lower levels of both TNF-a cells and SAA proteins for all intervals of serum testing. This is significant in that Tumor Necrosis Factor alpha (TNF-a) and Serum Amyloid A (SAA) are involved in systemic inflammation, and a reduction in inflammation would help explain the better health status and reduced number of medical treatments in these foals.
The data (IgG, TNF-a, and SAA) may indicate that the mares that received the bioactive proteins and their foals, had reduced markers related to stress-induced inflammation and immune activation. It has been suggested that SAA levels correlate well with disease activity in the early stages of inflammatory joint disease, a fact borne out in a study by Coverdale and Campbell, 2014, that showed a lengthening of stride and enhanced knee range in performance horses receiving bioactive proteins.
This improved immune competence and reduced over-stimulation of the immune system is consistent with results observed in farm animals, and suggests a transfer of stress biomarkers from mares to foals, likely through the colostrum. Thus, indications seem to point to the efficacy of bioactive proteins to promote overall well-being and stress reduction in pregnant and lactating mares and their foals - good news for breeders.