Poster SNGTV ElectroPidolate
Hypocalcaemia or milk fever appears when there is an imbalance in phosphocalcic homeostasis peripartum, primarily with highly productive, multiparous dairy cows. It affects on average between 0 and 10 % of the dairy cow population (l, 2, 4, 6) and has major sanitary and economic impacts. The objective of this study is to evaluate the effect of Vetalis intraruminal boluses of calcium pidolate and magnesium pidolate on the phosphocalcic metabolism and on the production of dairy cows as compared to other veterinary preventive products and a control group without supplements. Pidolate, associated with calcium and magnesium, is a very water-soluble organic salt that plays the role of active transporter of its cation right to the cytoplasm of the target cell, so improving its absorption rate.
Materials and methods
30 multiparous (≥ 2) Prim Holstein dairy cows, from the same farm, were divided up into 5 groups of 6 animals. Their calcaemia and phosphataemia were measured at various times (H-4, H0…) over 24 hours. Group 1 received 2 Vetalis boluses in 1 application, 1 to 4 hours before calving (total 7.56 g of Ca (Pidolate) and 1.19 g of Mg (Pidolate)); group 2 received 3 Vetalis boluses in 1 application, 1 to 4 hours before calving (total 11.34 g of Ca (Pidolate) and 1.785 g of Mg (Pidolate)); group 3 = negative control; group 4 received 3 boluses of Ca (total 129 g of Ca (Chloride and Sulphate)) in 3 applications (1 to 4 hours before calving, 4 to 5 hours after and 10 to 12 hours after); group 5 received 3 bottles of gel (total 156 g of Ca and 135 g of P (Diphosphate and Monophosphate) and 2.4 g of Mg (Chloride)) in 3 applications (1 to 4 hours before calving, 4 to 5 hours after and 10 to 12 hours after). The products were administered under the responsibility of the veterinary investigator. The potential milk production (PL) at the peak of lactation and the total potential production over 305 days were estimated using INRA equations: PLmaxpot. = PI*0.84 + 13 kg PL305pot. = PLmaxpot. *224 (for a multiparous cow) Where PI (kg) is the Initial Milk Production observed, which is equal to the average of the production on days 4, 5 and 6.
• Calcaemia The average calcaemia of groups 4 and 5 are higher than those of group 1 (2 Vetalis boluses). They are equivalent to those of group 2 (3 Vetalis boluses) between H0 and H+ 10 even though animals of group 2 received less calcium: 11.34 g as against 129 g in all for group 4 and 156 g for group 5. • Phosphataemia The average phosphataemia of group 1 that, however, did not receive any phosphorus, are comparable to those of group 5 between H0 and H+ 10, which received 135 g over 3 doses. They are even 7 to 23 % higher than those of control group 3.
• Milk production (MP) The estimated potential milk production at the peak of lactation shows a difference of 3 – 4 litres of milk between the groups 1, 2 and 5 as compared to group 3 (control), which means a bonus of 700 – 930 litres in the total estimated potential production over 305 days.
The results show, on the one hand, the effectiveness of pidolate salt as a carrier for calcium and, on the other hand, that the active ingredient mobilises the endogenous phosphorus. This property is interesting since it is known as a complication of hypophosphataemia in nearly 55 % of the cases of milk fever (5) making worse chances of recovery. According to the estimates for the potential milk production, the animals treated with the Vetalis boluses or with the bottles of drinkable gel would produce more milk than group 3 (control), which would represent an interesting result to the farm. Groups G1 and G2 (Vetalis boluses) could even produce between 22.5 % and 30 % more milk than in the previous season. The Vetalis bolus, based on calcium pidolate and magnesium pidolate, helps in having a good start to lactation by its effect on the phosphocalcic metabolism. According to the scientific literature, pidolate, through the γ-glutamyl cycle, seems to be the intra-cellular activator of a mechanism for the transport of amino acids at the level of the mammary glands (7), which could explain an improvement in the milk production among other factors.
A field trial would be needed to explore this hypothesis, while taking other factors that influence milk production into account. Out of the 30 animals studied, only one case of milk fever appeared in group 3 (control), which demonstrates the efficacy of the preventive treatments. Moreover, the animals of groups G1 and G2 (with the Vetalis boluses) appear to be more dynamic post-partum. In addition to possibly mobilising endogenous phosphorus, by participating in the glutathione cycle(3), responsible for the fight against oxidative stress, pidolate could be involved in a better fight against peripartum stress and improve the physical recovery of the animal.
Despite the fact that the concentrations of calcium and magnesium are less than in the competing products studied at the same time and the absence of phosphorus, the Vetalis bolus, based on Calcium Pidolate and Magnesium Pidolate, acts efficiently on the phosphocalcic metabolism of the dairy cow in peripartum. It also seems to clearly improve milk production and to have a positive effect on the animal regarding recovery after calving. Furthermore, the one single application of the Vetalis bolus is far less time consuming than the administration in several doses of the competing products. This new bolus has been the object of a patent by Vetalis in 2010.
• Thanks Our thanks go to Dr Pin, who carried out this test with the support of Drs Dubois and Casteret, as well as to the farmer, Mr Blanlœuil, for his vigilance.