Abstract #138
Section: Animal Behavior and Well-Being (orals)
Session: Animal Behavior and Well-Being I
Format: Oral
Day/Time: Monday 2:00 PM–2:15 PM
Location: Room 300 AB
Session: Animal Behavior and Well-Being I
Format: Oral
Day/Time: Monday 2:00 PM–2:15 PM
Location: Room 300 AB
# 138
Feeding behavior, dry matter intake and intake rate in dominant and subordinate dairy heifers allocated in competitive dyads.
Carolina Fiol*1, Ignacio Donadio1, Leticia Eustathiou1, Guillermo Matto1, María Noel Méndez1, Verónica Sánchez1, Francisco Triay1, Martín Aguerre2, Mariana Carriquiry3, Rodolfo Ungerfeld4, 1Departamento de Bovinos, Facultad de Veterinaria, UdelaR, Libertad, San José, Uruguay, 2Red Tecnológica Sectorial de Lechería, Montevideo, Uruguay, 3Departamento de Producción Animal y Pasturas, Facultad de Agronomía, UdelaR, Montevideo, Uruguay, 4Departamento de Fisiología, Facultad de Veterinaria, UdelaR, Montevideo, Uruguay.
Key Words: cattle, social hierarchy, social behavior
Feeding behavior, dry matter intake and intake rate in dominant and subordinate dairy heifers allocated in competitive dyads.
Carolina Fiol*1, Ignacio Donadio1, Leticia Eustathiou1, Guillermo Matto1, María Noel Méndez1, Verónica Sánchez1, Francisco Triay1, Martín Aguerre2, Mariana Carriquiry3, Rodolfo Ungerfeld4, 1Departamento de Bovinos, Facultad de Veterinaria, UdelaR, Libertad, San José, Uruguay, 2Red Tecnológica Sectorial de Lechería, Montevideo, Uruguay, 3Departamento de Producción Animal y Pasturas, Facultad de Agronomía, UdelaR, Montevideo, Uruguay, 4Departamento de Fisiología, Facultad de Veterinaria, UdelaR, Montevideo, Uruguay.
The objective was to evaluate feeding behavior, individual DMI and intake rate in dominant (DOM) and subordinate (SUB) pre-pubertal dairy heifers maintained under competitive situations. Holstein (n = 12) and Jersey × Holstein (n = 4) pre-pubertal heifers (250.8 ± 9.8 d old, 208.5 ± 13.9 kg; mean ± SEM) were allocated into 8 homogeneous dyads for 120 d (d 0 = beginning of measurements), and received a total mixed ration (TMR) on 1 feeder/day. The DOM and SUB heifers were determined by observation of the winner in agonistic interactions in each dyad after TMR supply. Behavioral activity of each heifer was recorded by instantaneous scan-sampling, every 10 min for 12 h (hour 0 = TMR), in 7 periods (corresponding to d 1, 21, 35, 60, 75, 100 and 120). Individual DMI was estimated with double marker technique, in 3 periods (I, II, and III corresponds to d 17–26, 78–87, and 112–120), while intake rate (DM/min) was calculated as DMI/eating time. Behavioral data were analyzed with PROC GLIMMIX, while DMI and intake rate were analyzed by PROC MIXED. During the first 5 h after feed delivery, DOM spent more time ruminating (12.2 and 8.4%, DOM and SUB; SE = 1.2; P < 0.01) and lying (18.6 and 17.4%; SE = 2.7; P = 0.04) than SUB, but SUB spent more time standing than DOM (30.0 and 34.8%, DOM and SUB; SE = 2.4; P = 0.05). Along the 12 h of recording, DOM spent more time eating than SUB on hour 4 (32.1 and 26.6%; SE = 3.0; P = 0.05) and 6 (15.9 and 10.2%, SE = 3.6; P < 0.01). While on hour 1 (11.3 and 16.9%, SE = 3.6), 2 (21.6 and 28.7%; SE = 3.6) and 4 (44.6 and 51.6%; SE = 3.6) SUB spent more time standing than DOM heifers (P < 0.01). Dry matter intake was similar for DOM and SUB (6.7 and 6.9 kg/d, DOM and SUB; SE = 0.3; P > 0.05), but SUB ate at a faster rate (0.044 and 0.049 kg/min, DOM and SUB; SE = 0.003; P = 0.02) on Period II compared with DOM heifers. In conclusion, SUB had greater intake rate, with no differences on food intake, spent less time ruminating, and showed more behaviors probably associated with greater levels of social stress than DOM heifers.
Key Words: cattle, social hierarchy, social behavior
