Blood calcium balance
X-Zelit is a simple tool to optimise transition feeding. An optimal transition feeding can reduce both clinical and subclinical hypocalcemia in dairy cows. around 50 percent of cows are suffering from subclinical hypocalcaemia. Hypocalcaemia reduces muscle function and immune response resulting in a knock-on effect to other disorders. Through lots of trials, tests and farm experiences X-Zelit has proven its effectiveness and unique mode of action.
Reduced number of empty days / Improved fertility
Hypocalcaemia has a negative impact on reproduction and cows with a low calcium level are having more empty days (Martinez et al., 2011), lower pregnancy rate (Caixeta et al., 2017) and a later heat (Rodriguez et al., 2017) than the cows maintaining a calcium level above 2.125 mmol/L (8.5 mg/dL) in the periparturient period.Supplementation of X-Zelit in the last 14 days of the dry period is increasing the plasma calcium level, and thus it is expected that X-Zelit has a positive impact on reproduction.
Increased milk yield / Higher feed intake
Other effect on production parameters were investigated. In the trial at Cornell University an average yield increase of 0.8 ECM was found in cows supplemented with X-Zelit (figure 4). The positive yield increase is a result from higher levels of fat and protein.
The feed intake was 0.5 kg DM higher for the X-Zelit group in the lactation, whereas the feed intake in the dry period was 0.6 kg DM lower for the X-Zelit group (figure 5). The production differences are at the same level as previous observations, but they were not significant in the trial at Cornell (Kerwin et al., 2018b).
Figure 4. Energy corrected milk during the first 4 weeks for cows supplemented with or without X-Zelit.
Figure 5. Dry matter intake before and after calving for cows supplemented with or without X-Zelit.
Better quality of colostrum
Use of X-Zelit will decrease the volume of colostrum around 10 % but increase the level of immunoglobulins with around 10 % - suggesting that the cows produce the same number of immunoglobulin but it is concentrated in a smaller volume using X-Zelit. Farmers will usually find a higher BRIX values of the colostrum when using X-Zelit.
Figure: Volume and IgG in colostrum for cows supplemented with X-Zelit in close-up compared with non-supplemented control
A higher calcium level during calving has a positive effect on many production characteristics. Among other things, the high level contributes to the cows being more vigorous after calving and having a higher feed intake. The higher feed intake is in this trial indicated by the rumination data (Figure 2).
Figure 2. Rumination in minutes per day over the first 82 days of lactation
The rumination time was higher from the start of lactation for the X-Zelit group as well as throughout the 82 days during, which the cows were observed. This indicates that cows that are off to a good start in lactation, retain the benefit for a very long period. The result is consistent with the Cornell experiment, where a 30 minutes/day increase in rumination was observed in the first week of lactation.