Epsilon Archive for Student Projects

Abstract

With the intensification of the cattle farming system, a high amount of easily fermentable carbohydrates is being fed to increase production and fulfill the nutrient requirement of the cows. Feeding high amounts of easily degradable carbohydrates such as starch can reduce the rumen pH of cows, resulting in the condition subacute ruminal acidosis (SARA). SARA has a great impact on the production, health, and welfare of the cow, leading to a decreased economy for the farmer. Hence, the diagnosis of SARA is important in the early stages. Diagnosis of SARA is done on the basis of rumen pH. The technology used previously for the determination of rumen pH was highly expensive and invasive and did not provide accurate data on rumen pH. With the advancement of technology, a wireless sensor bolus was developed, which is non-invasive, farmer-friendly, and provides continuous monitoring of rumen pH. The efficacy of this technology and its ability to detect minute variations in rumen pH are still in question. Moreover, due to its battery lifespan and drift over time, the use of this technology in real farm conditions is highly expensive and unfeasible. Considering it, an alternative indicator of SARA must be found, which should be noninvasive, cheap, and accurate. Hence, this study aims to monitor the effect of SARA inducing diet on rumen pH using a wireless sensor bolus, together analyze the effect of inducing diet on milk yield (MY), dry matter intake (DMI), and milk parameters, such as milk fat, milk protein and milk fat to protein ratio.
A continous study was performed on 25 primiparous cows in 3 periods lasting for 52 days. Rumen sensor bolus was applied on the first day of the study. Then, a low concentrate diet containing a 48:52 concentrate-to-silage ratio was fed for the first 9 days (CONT1 period). Then, from day 10 to 32, the SARA inducing diet containing a 64:36 concentrate-to-silage ratio was fed (SAR2 period). Finally, the study was ended by feeding the same CONT1 diet from day 33 to day 52 (RECOV3). During the period, rumen pH was monitored every day throughout the period. Daily DMI and MY was measured throughout the period. A sampling of milk was done for the last two days of each period to analyze the milk parameters.
Variation in rumen pH across periods and fluctuations in rumen pH within a day was seen in this study. A significant drop in mean rumen pH and an increase in the mean duration of a cow with rumen pH 6 was reported in the SAR2 period, which instantly reverted back to normal when the low concentrate diet was fed during the RECOV3 period. Using the rumen pH metrics, cows that were likely to be in SARA were identified. No changes were observed in MY throughout the periods. Significant differences in results were observed for DMI and milk parameters. Considering the results of this study and the outcomes from other studies, it was concluded that the rumen sensor bolus was able to detect minute changes in rumen pH throughout the day, making it an efficient device for monitoring rumen pH in cows. Additionally, the use of other parameters, such as DMI, MY, and milk parameters, as indicators of SARA demands more studies that include the factors that have a direct effect on those parameters.