Abstract #W5

# W5
Effect of using fresh ryegrass/berseem clover as forage basis for TMR on dairy cow behavior.
F. Pereira1,2, A. Torres1, M. F. Donoso1, D. L. Teixeira1, L. Boyle3, L. P. M. Filho2, D. Enriquez-Hidalgo*1, 1Facultad de Agronomía e Ingeniería Forestal, Pontificia Universidad Católica de Chile, Santiago, Región Metropolitana, Chile, 2Laboratorio de Etología Aplicada, Universidade Federal de Santa Catarina, Florianópolis, Santa Catarina, Brazil, 3Teagasc, Animal & Grassland Research and Innovation Centre, Moorepark, Fermoy, Co. Cork, Ireland.

Cows have a natural selection activity regarding their feed as they can make dietary choices or be reluctant facing a new diet. Thus, a change in the diet composition can change their feeding behavior, affecting feed intake. The objective of the study was to evaluate the effect of using fresh ryegrass/berseem clover (MIX) and alfalfa hay/maize silage (CON) as forage basis for TMR on dairy cow behavior. Lactating dairy cows (n = 24) were blocked according to productive traits and allocated to each TMR diet for 10 weeks. Cows were kept in individual pens (6 × 3.5 m) with free access to the TMR and water. Cow behavior was assessed through video recordings between milking times (10 to 14 h and 16 to 20 h) by scan sampling every 10 min during 4 d in wk 1, 6 and 8. Behaviors: eating, ruminating or idling, walking and other (e.g., grooming, drinking) were registered. The occurrence of social interactions with neighboring cows were registered during 60 s every 10 min. Individual (n = 16) lying time was recorded over 4 d/week using HOBO dataloggers fitted to the cow’s hind leg. Individual feed intake and milk production was daily recorded. Data were analyzed using generalized linear mixed models, including the week, diet type and its interactions as fixed effects and block as random effect. The day within week was used as a repeated measure. Ingestive behaviors, eating (33.9 ± 4.1%), ruminating (17.2 ± 2.4%) and idling (40.0 ± 6.6%) were not affected by TMR diet (P < 0.05). Feed intake tended to be higher with CON than with MIX diet (30.4 vs 25.1 ± 1.8 kg DM/d P = 0.05). There was no effect of the TMR diet on lying time (11.7 ± 0.38 h/d), number of lying bouts (6.9 ± 0.33/d), or bout duration (1.7 ± 0.06 h/bout). Social interactions (1.74 ± 0.65) and walking behavior (0.35 ± 0.01%) were not influenced by TMR diet (P < 0.05), but cows showed a higher frequency of “other” behaviors when fed with CON than when fed with MIX diet (9.2 vs 7.6 ± 0.07%; P < 0.05). We conclude that the TMR diets used in this study had minimal effects on dairy cow behavior. The study was supported by FONDECYT 11160697

Key Words: fresh forage, dairy cow, behavior