Reactivity of Nellore steers in two feedlot housing systems and its relationship with plasmatic cortisol

Human animal relationships in Bos indicus cattle breeds addressed from a Five Domains welfare framework

The present review has two objectives, the first is to investigate the differences in temperament between Bos indicus and Bos taurus breeds and determining the effects on production due to positive treatment and to compare this with negative HAR, by using the Five Domain Model as framework. The second objective is to discuss potential strategies to achieve better HAR when working with Bos indicus cattle. Bos indicus are more reactive and temperamental than Bos taurus cattle. When human animal relationships (HAR) are evaluated, Bos indicus cattle may react with greater intensity. They may be more likely to develop a negative emotional state, especially in extensively raised Bos indicus cattle that are handled only a few times each year. Bos indicus cattle can have positive emotional states when they have frequent positive interactions with people. Interactions with people, both positive and negative, would be in the fourth Domain of the Five Domains model. Cattle that are more reactive during handling may also have lower weight gain, even when they have abundant feed. This would be in the first Domain of Nutrition. When cattle are handled in races and corrals, injuries may be more likely to occur. Injuries and bruises would be in the third Domain of Health. Injuries could be caused by either poor handling practices by people or poor handling facilities. Yelling or electric prod use would be examples of poor HAR. Second Environmental Domain issues may be broken facilities or slick, slippery floors that are associated with falls.

Relationships between temperament, meat quality, and carcass traits in Nellore cattle1

The aim of this study was to evaluate the relationship between temperament in Nellore bulls with carcass and meat quality traits. In total, 1,400 bulls were studied, and temperament was assessed using two measurements: movement score (MOV) and flight speed test (FS). Both MOV and FS were measured at two time points, with background (MOVb and FSb) temperament measured at yearling age, ~550 d after birth, and the preslaughter (MOVps and FSps) temperament measured at the end of the feedlot period. The change of temperament resulting in an increase or decrease in reactivity was also used to measure meat quality. The traits used to define carcass and meat quality included carcass bruises (BRU), hot carcass weight (HCW, kg), ribeye area (REA, cm2), backfat thickness (BFT, cm), marbling score (MS), meat pH after thawing (pH), presence or absence of dark cutters, color parameters of luminosity (L*), redness (a*) and yellowness (b*), cooking loss (CL, %), and Warner-Bratzler shear force (WBSF, kg). A principal component (PC) analysis was initially applied to the carcass and meat quality traits, followed by logistic regression models and linear mixed models to evaluate the effects of temperament on carcass and meat quality. The risks of carcass bruises and dark cutters did not differ as a function of any temperament trait (P > 0.05). In turn, animals classified as high MOVb (reactive) had lower PC3 values (P = 0.05), CL (P = 0.02), and tended to have lower MS (P = 0.08). In addition, animals classified as high FSb (faster and reactive cattle) produced carcasses with smaller REA (P < 0.01), higher meat pH (P < 0.01), lower color gradients (L*, P = 0.04; b*, P < 0.01), and lower PC1 and PC4 scores (P < 0.01) when compared with the low FSb class. For preslaughter temperament, high MOVps was related to lower color a* (P = 0.04), whereas high FSps was related to lower HCW, MS, and PC2 (P < 0.01) than the calmer ones (low FSps). The reduction in MOV was related to more tender meat, and the reduction in FS to heavier carcass and brighter meat. We conclude that excitable temperament in Nellore cattle may have negative effects in some of the carcass and meat quality attributes assessed, mainly those related to muscle deposition on carcass and color gradients. Measurement of temperament before the cattle entered the feedlot was a better predictor of carcass and meat quality traits, compared with temperament assessment at the end of the feeding period.

Flight speed as an indicator of Zebu cattle growth performance and suitability to the feedlot environment

Context Studies assessing the relationship between cattle reactivity and growth performance, as well as suitability to the feedlot, in Zebu cattle are limited. Based on previous studies using Bos Taurus cattle, it is expected that reactivity measured at weaning could be used as a predictor of feedlot performance, and that cattle with greater flight speed (FS) would have reduced average daily gain (ADG). Aims The aims of this study were to (1) determine if FS (m/s) measured before entry into the feedlot could be used as a predictor of cattle performance, (2) evaluate the consistency of FS over time, and (3) determine when FS should be measured to best predict animal suitability to the feedlot. Methods A total of 54 Nellore and 40 Guzerat calves were assessed by using FS, which was collected at the time of (FS0) and 1 week after weaning (FS1), as well as on Day 28 (FS28), 56 (FS56) and 168 (FS168) after entry into the feedlot, and a FS average was calculated using FS28, FS56 and FS168 (FS28–168). Performance using ADG (kg/calf.day) was calculated for each animal over three periods: ADG1–28, ADG28–168 and ADG1–168. Bunk attendance (min/calf.day) was recorded over a 173-day feeding period. Key results The ADG28–168 was reduced by 0.14 kg/calf.day for each unit increase in FS0 (P &lt; 0.05). Both ADG28–168 and ADG1–168 were reduced by 0.02 kg/calf.day for each unit increase in FS1 (P ≤ 0.01), but neither FS0 nor FS1 was associated with ADG1–28 (P &gt; 0.10). A significant increase was observed between FS1 and FS28 (P &lt; 0.01), followed by a reduction in FS56 (P &lt; 0.01) and FS168 (P &lt; 0.01). Conclusion FS measured at or within 1 week of weaning has the potential to be used as an indicator of feedlot growth performance in Nellore and Guzerat cattle. Implications Although our results do not indicate the efficacy of FS as a predictor of early suitability of cattle to the feedlot, it does have the potential to support its recommendation as an indicator of overall feedlot growth performance in Nellore and Guzerat breeds.

Frequent handling of grazing beef cattle maintained under the rotational stocking method improves temperament over time

Our aims were to assess the effects of handling frequency on temperament evolution in cattle kept under rotational stocking method (RSM), as well as to compare the temperament of animals maintained under rotational versus alternate stocking (ASM) methods. We evaluated 4256 males raised on pasture from four private properties (Farms 1–4), for a total of 9628 observations. The study was divided into two complementary approaches. In the first one, monthly visits were conducted at 35-day intervals to assess the cattle temperament (n = 1979) raised on grazing system using RSM, while, in the second approach, we evaluated the temperament of cattle (n = 3600) kept under two different stocking methods, namely, (1) RSM (n = 2007), characterised by a high frequency of animal handling and a 4-day grazing period, and (2) ASM (n = 1593), characterised by a low frequency of handling and a 20-day grazing period. Composite reactivity score (RS), and flight speed (FS) were considered as temperament indicators. Reductions of RS and FS means were observed during successive assessments under RSM. Significant effects of stocking method on FS (P < 0.05) and RS (P < 0.01) were found, with lower FS and RS means for animals under RSM than for those under ASM. In conclusion, the frequent handling in the rotational stocking method favoured the improvement of cattle temperament over time, with lower levels of reactivity among cattle raised under this stocking method than with animals raised under the alternate stocking method.