Associations between feed push-up frequency, feeding behavior and milk yield in dairy buffaloes

Feeding management factors have great potential to influence feeding behavior of dairy cows, which may have implications for their performance. The objective of this pilot study was to assess the effects of feed push-up frequency on the feed behavior and milk yield of Italian Mediterranean dairy buffaloes. Lactating Italian dairy buffaloes (n = 95±6.2, parity =4 ± 1.1; DIM: 97±8.2 mean ± SD) were housed in a freestall, milked twice per day, and offered ad libitum access to water and a total mixed ration (containing, on a dry matter basis: 25% corn silage, 25% grass/alfalfa haylage, 30% high-moisture corn, and 20% protein/mineral supplement), provided once/day. The pen was the experimental unit with the study lasting 40 days. Buffaloes within the pen were exposed to each of 2 treatments in a crossover design with 15-d treatment periods and a 10-d adjustment period in between treatments; treatment 1 had 3 feed push-up a day, whereas treatment 2 had 2 feed push-up a day. Dry matter intake and milk yield were recorded daily whereas every five days feed samples of fresh feed and orts were collected for particle size analysis and chemical evaluation. For the particle size analyses two separators have been used: the Penn State Particle size separator, fitted with 3 screens (19, 8, and 1.18 mm) and a bottom pan, resulting in 4 fractions (long, medium, short, fine) and a Z-box fitted with a 2.38mm screen for determination of the physical effectiveness factor of the TMR. Sorting was calculated as the actual intake of each particle size fraction expressed as a percentage of the predicted intake of that fraction. Feed push-up frequency had no effect on milk yield (13.26 ± 0.04 kg/d vs 13.021±0.05 kg/d for 3 vs 2 push-up) or feed sorting. Buffaloes sorted against long particles (76.4 ± 31.96%) and for short (99.38 ± 0.72%) and fine (100.06 ± 1.09%) particles. The pef of the TMR was not affected by the feed push-up frequency. Dry matter intake increased with increased push-up frequency (41.71±0.03 kg vs 37.11±0.03 kg for 3 vs 2 push-up). These preliminary results suggest that altering feed push-up frequency increases intake but doesn’t affect feed sorting or milk production. Further studies are needed to evaluate long term effects of feeding frequency on milk yield and composition