Cows in conventional herds follow a structured routine and receive all their nutrients from a total mixed ration, while cows in herds with robotic milking systems have the opportunity to be milked more frequently and fed more precisely, but there are challenges in maintaining a consistent milking frequency and finding the right balance of feed ingredients.
- Since the first commercial systems appeared in 1992, automatic milking systems (AMS) have been installed at an increasing rate
- In most cases, cows obtain all their nutrients from a TMR; in herds equipped with robotic or AMS, a fraction of their nutrients is provided during milking, mainly as a means to attract cows to the milking system, whereas the remaining fraction is supplied in the feed bunk through a partial mixed ration (PMR)
- Opportunity from AMS resides in the possibility of milking more frequently, assigning different milking frequencies to different cows, and feeding cows more precisely or closely to their nutrient needs, potentially resulting in improved feed efficiency and economic returns rendering a more profitable production system than when using a single TMR
- From a behavioral standpoint, free traffic conditions coupled with frequent deliveries of the PMR at the feed bunk and limiting concentrate allowance in the AMS to 3 to 4 kg/d seem more beneficial for milking cows in a AMS
- Tremblay et al (2016) found a negative association between concentrate allowance in the AMS and milk yield, the same study reported a positive association between the percentage of feed allowance that was not consumed and milk production. This emphasizes that the potential advantages of feeding cows more closely to their nutrient needs are only achieved if the precision at which these nutrients are offered is high
- Restricting concentrate allowance to <3 to 4 kg/d is recommended to maximize economic returns and minimize variation in nutrient intake
| Item (per cow per day) | Free traffic | Guided traffic | SE | P-value |
|---|---|---|---|---|
| Total milkings (no.) | 2.2 | 2.5 | 0.04 | <0.001 |
| Fetched milkings (no.) | 0.5 | 0.1 | 0.03 | <0.001 |
| PMR1 intake (kg) | 18.6 | 17.6 | 1.34 | 0.24 |
| PMR1 meals (no.) | 10.1 | 6.6 | 0.30 | <0.001 |
| Concentrate intake (kg) | 2.5 | 2.5 | 0.09 | 0.99 |
| Milk production (kg) | 29.8 | 30.9 | 1.74 | 0.32 |
| Milk fat (%) | 3.65 | 3.44 | 0.078 | 0.06 |
| Milk protein (%) | 3.38 | 3.31 | 0.022 | 0.05 |
Bach et al (2008) reported that key management aspects, such as age at first calving, amount of feed refusals, number of feed pushups, and stocking density, explained more than 55% of the variation in milk production in 47 herds that were feeding exactly the same TMR Bach, A., & Cabrera, V. (2017). Robotic milking: Feeding strategies and economic returns. Journal of Dairy Science, 100(9), 7720–7728.
