Abomasal damage (AD) and poor rumen development (RD) are 2 common gastric impairments in veal calves. The question is: do they negatively impact welfare? We searched for links between gastric health and behavioral indicators of welfare in 2 experiments (Exp). Exp1: 48 calves (8 to 26 wk, 3 calves/pen) were fed milk replacer with 1 of 4 solid feed (SF) amounts (0, 40, 80, 120 kg DM/calf provided over 4 months, twice daily and increased on a weekly basis) with 50% concentrate, 25% maize and 25% straw on DM basis. Exp2: 160 calves (12 to 29 wk, 5 calves/pen) were fed milk replacer with 1 of 4 SF amounts (20, 100, 180, 260 kg DM/calf fed over 4 months, once daily and increased on a weekly basis) and 1 of 2 SF compositions (80% concentrate, 10% maize, 10% straw or the one used in Exp1). Behavior (ruminate, tongue play, manipulate object, lie, groom, play, idle) was noted using instantaneous scan sampling (5 min intervals for 30 min, 7 scans/d) at 24 wk. At slaughter, AD (number and size of lesions) and RD (score from 1 to 4, with 4 being ‘well developed’) were noted. For each Exp, a principal component analysis with behavioral and gastric health variables was done. Loadings >0.40 were considered of interest. The different diets ensured diversity in gastric health and behavioral variables but were not included in the analysis. RD and AD were compared across Exp using genralized linear models. RD was similar in both Exp (1.9±0.05; P=0.381), whereas AD was worse in Exp2 (4.2±0.41 vs 2.2±0.37; P=0.011). The first 2 principal components (PC) had eigenvalues >1 and, together, explained 35.8% and 33.8% of the variance for Exp 1 and 2 respectively. Exp1: PC1 did not include gastric health variables. PC2 loaded high on RD and AD, and low on tongue play. This was expected because RD occurs with high amounts of SF, which increase rumination and decrease tongue playing. Exp2: PC1 loaded high on RD and ruminate, and loaded low on manipulate object and idle: 2 potential indicators of poor welfare. PC2 loaded high on AD, lie and idle, and loaded low on play. RD was linked with indicators of good welfare: i.e. high rumination and low abnormal behaviors, i.e. tongue play and manipulate object. AD was linked with indicators of good welfare (i.e. low tongue play) and poor welfare (i.e. low play). Tongue playing may protect against AD by reducing stress. The association between AD, lie and idle may indicate pain, because animals in pain are less likely to perform active behaviors. Finally, this study does not support the idea that a developed rumen protects against AD.
|Title of host publication||Proceedings of the 50th Congress of the International Society for Applied Ethology|
|Publisher||Wageningen Academic Publishers|
|Publication status||Published - 12 Jul 2016|
|Event||50th Congress of the International Society for Applied Ethology - Edinburg, United Kingdom|
Duration: 12 Jul 2016 → 15 Jul 2016
|Conference||50th Congress of the International Society for Applied Ethology|
|Period||12/07/16 → 15/07/16|