Crush Score Research Articles

Genetic associations between temperament and performance traits in Nellore beef cattle.

The aim of this study was to estimate genetic associations between temperament and performance traits. Temperament was evaluated in yearling male and female Nellore cattle, using four traits: temperament score (TS), for assessing animals' reactions in a corral pen (n = 25,691); movement score (MOV), for animals' movements recorded inside the crush; crush score (CS), for animal's general reactivity inside the crush; and flight speed (FS), for the speed (in m/s) at which the animals exited the crush (n = 11,697, for the last three methods); for all the temperament traits, lower scores indicate animals with calmer temperament. Performance traits were visual scores for conformation (C), finishing precocity (P) and muscling (M) evaluated at yearlings, and average daily gain (ADG) was estimated from weaning to yearling. Bayesian inference using Gibbs sampling was applied to estimate (co)variance components and genetic and phenotypic parameters. Heritability estimates for the temperament traits ranged from 0.07 (CS) to 0.28 (FS). Genetic correlations of the temperament traits with ADG and C, P and M were negative and ranged from -0.02 to -0.31. Phenotypic correlations were negative and consistently lower than the genetic, ranging from -0.08 to -0.02. It was concluded that the temperament traits assessed had favourable genetic correlation estimates with the performance traits studied. However, indirect responses in temperament when selecting for higher ADG and visual scoring system of C, P and M, will be low.

Caracterización de la reactividad conductual frente al manejo y su relación con el Cortisol sanguíneo, contusiones y pH de la carne en novillos

SuMMAry In order to e xplore the capacity of behavioural tests to predict the incidence of high pH meat (dark cutting) in commercial setting, we assessed the relationship between behavioural reactivity, physiological parameters and meat quality in steers. Fourty-two steers were weighed individually in a scale (2.5x3x2.5m) to assess two behavioural parameters: crush test and exit velocity. Repeatability of the behavioural responses during 3 weighing events was calculated and a consistency scale was created to determine consistency of the parameters. Blood samples were collected from each steer after the second crush test and at bleeding, then analyzed for serum cortisol. Bruising and pH were registered after slaughter on the carcasses. Crush score was highly consistent (r = 0.81-0.87) and exit velocity moderately consistent (r = 0.44-0.60), however individual differences were detected in the “acclimation” and “sensitization” to the test through time. Higher crush score was associated with higher on farm cortisol concentration. Steers producing carcasses with multiple bruises (3-4) had a higher serum cortisol concentration at bleeding (P < 0.05) than steers with less carcass bruising. Behavioural parameters, carcass bruising and meat pH were not statistically associated. We conclude that it is important to evaluate behavioural reactivity using serial tests and we recommend further exploration on the capacity of reactivity tests to detect differences in reactivity that can be reflected in differences in meat quality parameters.

Validity and feasibility of qualitative behavior assessment for the evaluation of Nellore cattle temperament

The aims of this study were to assess the validity and the feasibility of the qualitative behavior assessment (QBA) method as indicator of Nellore cattle temperament under field conditions, evaluating its associations with four other traditional methods and weight gain. The temperament and live weight of 2229 Nellore cattle was assessed at approximately 550 days of age. Five measurements of cattle temperament were recorded: flight speed test (FS, in m/s), visual scores of movement in the crush (MOV), crush score (CS), temperament score (TS), and the qualitative behavior assessment method (QBA), by using a list of 12 behavioral based adjectives as descriptors of temperament. Average daily weight gain (ADG) was calculated for each animal. For statistical analysis of QBA data, the Principal Component Analysis was used. A temperament index (TI) was defined for each animal using the scores for the first principal component. Pearson's correlation coefficients were estimated between TI with FS and ADG. A mixed model ANOVA was used to analyze the TI variation as a function of TS, CS, and MOV. The score plot for the first and second principal components was used to classify the cattle in four groups (from very bad to very good temperament). The first principal component explained 49.50% of the variation in the data set, with higher positive loadings for the adjectives ‘agitated’ and ‘active’, and higher negative loadings for ‘calm’ and ‘relaxed’. TI was significantly correlated with FS (r=0.49; P<0.01) and ADG (r=−0.10; P<0.01). The means of ADG, FS, and the temperament scores (CS, TS, MOV) differed significantly (P<0.01) among the four groups, from very bad to very good temperament. The QBA method could discriminate different behavioral profiles of Nellore cattle and were in agreement with other traditional methods used as indicators of cattle temperament. Additional studies are needed to assess the inter- and intra-observers reliability and to study its association with physiological parameters.

Precalving temperament and maternal defensiveness are independent traits but precalving fear may impact calf growth1

Human safety can be compromised by the response of beef cows to handling or when defending their calf. However, little is known about how precalving temperament, postcalving defensiveness, and maternal care are related. The impacts of cow temperament on calf neonatal vigor and ADG are also unknown. Data were collected on 2 farms (Farm 1, n = 143, 1 parity; Farm 2, n = 237, 2 parities). Temperament was recorded before calving when restrained in a crush (crush score), on exit from the crush (flight speed), and when isolated with a handler. Defensiveness was recorded within 4 d after calving during handling of the calf. Maternal interactions with the calf and calf vigor were recorded for 3 h after calving (Farm 1 only) and ADG was measured over 7 mo. Crush score and flight speed were repeatable within a parity (range in repeatability 0.33 to 0.49; P < 0.001). Crush score (0.50; P < 0.001) and defensiveness (up to 0.71; P < 0.001) were repeatable across parities. Temperament and defensiveness were unrelated on Farm 1; on Farm 2 a fearful crush score was associated with heightened defensiveness as measured by vigorous movement during calf handling (P < 0.001). Temperament and defensiveness were unrelated to calving ease or the amount of maternal behavior shown to the calf. At Farm 1, cows that exited the crush quickly had calves with a lighter birth weight (P = 0.023) and those that were agitated when isolated had calves with a decreased ADG (P = 0.017). Defensiveness was unrelated to ADG and neither temperament nor defensiveness affected calf vigor. Cow precalving temperament and postcalving defensiveness are repeatable but appear to be independent traits, neither of which is related to maternal interactions with the neonatal calf. Reducing precalving fearfulness should not affect postcalving behavior and changing postcalving defensiveness should not affect other maternal care traits. Fearful cows may produce calves with decreased birth weight and ADG, which, if confirmed, suggests that cow fearfulness may have wider economic implications than previously realized.

Genetic variability for temperament indicators of Nellore cattle1

The aim of this study was to estimate genetic parameters of 4 temperament indicator traits for Nellore cattle and evaluate the possibility of using such traits as selection criteria in breeding programs. Temperament was assessed for 23,420 male and female animals at 550 d of age, which were born between 2002 and 2009. A temperament score (TS) was used, which is based on a scale from 1 to 5 and considers the reaction of animals after exiting the crush. Moreover, 9,150 individuals born in 2008 and 2009 were measured for these characteristics: movement score (MOV), where animals were scored from 1 to 5 according to their movement inside the crush; crush score (CS), which assigns scores from 1 to 4 for the general reactivity inside the crush; and flight speed (FS), which is a recording of the speed (m/s) at which animals exit the crush after being weighed. The weaning weight (WW) was included in the multitrait analysis to reduce the effect of the selection performed at weaning. Bayesian inference using Gibbs sampling was applied to estimate (co)variance components and breeding values of the animals. The model included random direct additive genetic and residual effects, fixed effects of contemporary groups, age of the dam (classes), and age of the animal as covariate (linear and quadratic effects for WW and TS, and only linear effects for the other traits). A linear model was applied to WW and FS, whereas a threshold model was used for TS, CS, and MOV. Heritability estimates for FS, TS, CS, and MOV were 0.35, 0.15, 0.19, and 0.18, respectively. The genetic correlation estimates of FS with TS (0.85), CS (0.85), and MOV (0.76) were high, although the phenotypic correlations were low (between 0.18 and 0.25). For CS and MOV, the genetic and phenotypic correlation estimates were high (0.99 and 0.71, respectively). We concluded that all of the temperament indicator traits addressed in this study presented enough genetic variability to respond to selection; however, the use of FS would result in a faster genetic gain. With regard to the practical applicability in breeding programs, the use of FS is also favorable because it produces data on a continuous scale, allows for recording of the data electronically, and requires low investment.

Having and being an other-sex crush during early adolescence

This study examined other-sex crush experiences (both having and being perceived as an other-sex crush) among 544 young adolescents (mean age=12.74 years). Results indicated that 56% had at least one current other-sex crush, with little overlap between crushes, friends, and boyfriends/girlfriends. Significant associations between other-sex crush scores (scores reflecting the number of crush nominations received) and physical attractiveness, relational aggression, physical aggression, and popularity, as reported by same-sex and other-sex peers, were found. In addition, crush scores were (a) associated with same-sex likeability for boys (but not girls) and (b) uniquely related to peer nominations of popularity and physical attractiveness, as reported by other-sex peers. Neither having nor being perceived as an other-sex crush was uniquely related to loneliness. Taken together, the findings suggest that other-sex crushes are normative experiences during early adolescence that warrant further research attention.

Associations between response to handling and growth and meat quality in frequently handled Bos taurus beef cattle1

Fearful behavioral responses to handling (temperament) are undesirably associated with ADG and meat quality in infrequently handled Bos indicus cattle. It has never been assessed whether these relationships exist in calmer Bos taurus breeds in systems where handling is more frequent. Such systems predominate in some countries where beef production is a major agricultural activity. During fattening, 144 crossbred cattle from Limousin and Aberdeen Angus sires were assessed for temperament using 4 approaches: response to movement along a race (race score; 4 occasions), restraint in a crush (crush score; 4 occasions), flight speed from the crush (flight speed; 4 occasions), and isolation in a pen with a human (isolation score; 1 occasion in yr 1, 2 occasions in yr 2). Measurements of ADG were made between birth and slaughter and between 16 and 18 mo of age during fattening. Fattening occurred indoors on a complete mixed diet fed for ad libitum intake. Meat quality was measured by pH, color, and Volodkevitch shear force and by a sensory panel. The repeatability of temperament traits was 0.17 (race score), 0.35 (crush score), 0.51 (flight speed), and 0.36 (isolation score). The proportion of the total variance of temperament traits attributable to the sire and the social group was low (0.003 to 0.402). However, the sire did affect behavior in all tests apart from the crush score (ranging from P = 0.02 to P < 0.001). Correlations between behavior in the different tests (ranging from r = 0.21 to 0.54, and P = 0.02 to P < 0.001) apart from between-flight speed and isolation score indicate that fearful behavior was consistently shown across assessment methods. A calm response in the crush score test was associated with a greater ADG during fattening (P = 0.05), whereas a calm response during the isolation test was associated with a greater ADG in cold carcass weight (P = 0.02). Animals with a calm isolation score had less tender meat as judged by the sensory panel (P = 0.03), but no other effects were apparent between temperament and meat quality measures, although several tendencies (0.06 ≤ P ≤ 0.10) were found. Temperament did not appear to relate to meat quality in this study of frequently handled Bos taurus genotypes, which is in contrast to other studies using different beef production systems. Genetic correlations between temperament and meat quality under these conditions could, although not measured in this study, still exist in the absence of phenotypic correlations.

Temperament and hypothalamic-pituitary-adrenal axis function are related and combine to affect growth, efficiency, carcass, and meat quality traits in Brahman steers

Associations between temperament, stress physiology, and productivity were studied in yearling Brahman steers (n = 81). Steers differed in calpain system gene marker status; 41 were implanted with a hormonal growth promotant at feedlot entry. Temperament was assessed with repeated measurements of flight speed (FS) and crush score (CS) during 6 mo of backgrounding at pasture and 117 d of grain finishing. Adrenal responsiveness was assessed with ACTH challenge, with plasma samples collected immediately before and 60 min after challenge. Steers with higher FS and CS had higher prechallenge plasma cortisol, glucose, lactate, and nonesterified fatty acid concentrations. The ACTH-induced cortisol response was unrelated to FS or CS, but glucose remained higher after challenge in flightier steers. The hormonal growth promotant reduced adrenal responsiveness; tenderness genotype had no effect. When temperament assessments and cortisol concentrations before and after challenge were combined in a principal components analysis, four vectors accounting for 38%, 25%, 18%, and 9% of the variation were identified. The first vector had significant loadings on temperament and prechallenge cortisol; increasing scores were associated with increased plasma glucose, lactate, and nonesterified fatty acid and with reductions in BW and feedlot growth rates, carcass fatness, and muscle pH. The second vector loaded only on ACTH-induced cortisol response; increased scores related to increased residual feed intake, number of daily feed sessions, and meat marbling score. The third and fourth vectors had different loadings on FS and CS and appeared to identify different aspects of temperament measured by FS or CS. Fewer associations were found between the third or fourth vectors and productivity traits, possibly because of lower variance accounted for by these vectors. In conclusion, temperament was related to prechallenge cortisol but not to ACTH-induced cortisol response. Principal components analysis separated these traits into separate components, which in turn had different relations with productivity traits. The largest component of temperament was described similarly by FS and CS, but there were smaller components that these described differently. There were some temperament-related differences in the metabolic status of the steers which were not related to the variation in cortisol, suggesting involvement of the sympatho-adrenal-medullary axis in these temperament-related effects.

Consistency of flight speed and response to restraint in a crush in dairy cattle

Flight speed (FS) is an objective measure of the behavioural response to handling procedures in beef cattle but to date there is no published work on dairy cattle. It is useful to determine whether there is consistency in FS in dairy cattle, and assess the relationship between FS and other subjective measures of responsiveness in dairy cattle. The aims of this study were to: (a) evaluate the repeatability of the FS and crush score (CS) test in dairy cattle by repeated measurements and (b) examine the correlation of FS and CS with reactivity responses in a human approach test (HAT). FS and CS measurements for 55 Holstein–Friesian heifers were conducted three times at 4-week intervals. Flight response to a HAT was assessed in the passageway of the home-pen on a subset of 33 animals. On completion of the HAT, an assessment of six qualitative terms (at ease, friendly, bold, docile, shy, fearful and nervous) were assessed on a visual analogue scale according to a subjective judgement of whether a cow scored low or high for each term. Correlations between the three monthly repetitions of FS measurements were all significant and positive (FS 1,2: r s = 0.36, P = 0.007; FS 2,3: r s = 0.31, P = 0.002; FS 1,3: r s = 0.47, P < 0.001) which indicates a level of individual consistency. No significant correlations between the three monthly repetitions of CS measurements were found. The mean FS was correlated with HAT flight response ( r s = 0.42, P = 0.004). However, no significant correlations existed between the HAT and the CS. In conclusion, the results suggest that both HAT and FS measurements provide consistent (both intra- and inter-measure) assessments of temperament under these handling situations in dairy cows.

English

&nbsp; The objective of the current study is to compare the behavioural responses of Xhosa lob-eared, Nguni and Boer goats and their crosses to blood collection and rectal palpation. A total of 48, six- month old castrated male indigenous goats of the Xhosa lob-eared, Nguni and Boer goats and their crosses were kept at the University of Fort Hare Farm, South Africa for eight weeks. The goats were randomly assigned to four pen groups with each pen having three goats of the same breed among the 12 goats in each pen. Immediately after blood and faecal collection, behavioural measurements through vocalization scoring (VS), pen scoring (PS), crush scoring (CS), flight speed (FS) and flight time (FT) were recorded for each goat every forth-night for 8 weeks. The Nguni was the most temperamental (p &lt; 0.05) and the Boer goats were the most calm. There were significant increases in the behavioural scores of the four breeds during the successive weeks of handling. It can be concluded that the Boer goats had the calmest temperament, followed by the crossbreds, and lastly the Xhosa the Nguni were the most combative. &nbsp; Key words:&nbsp;Indigenous goats, crush score, flight speed, pen score, temperament, welfare.

The relationships between temperament during routine handling tasks, weight gain and facial hair whorl position in frequently handled beef cattle

A relationship has been described between facial hair whorl position and temperament in infrequently handled beef cattle when both traits were measured on categorical scales. Hair whorl position has also been found to relate to daily weight gain in dairy heifers. Using both a categorical scale and a modified approach in which hair whorl position was recorded as a more continuous variable, the relationship between whorl position and temperament in commercially relevant contexts was examined using frequently handed beef cattle ( Bos taurus). The behaviour during restraint in a handling crush and flight speed upon exit from the crush were recorded for 76 steers and heifers (5 European crossbreeds) on 4 occasions. Temperament during restraint was recorded using both a subjective categorical score (crush score; 1–4 scale from calm to violent reaction) and, from videos, by the durations of behaviours pushing/pulling back against the bail of the crush, shaking, neck stretching, head swaying and head rising/lowering. Using still photographs, hair whorl position was recorded both categorically and as a continuous variable with respect to its position between the crown of the head and the nostrils. Weight gain was measured monthly during the 3 months of the study. Cattle with whorls located towards the top of the head on the categorical scale received a crush score indicative of greater restlessness (mean crush scores 2.70, 2.03, 2.16 and 2.11 S.E.D. 0.91, for high, middle, low and absent whorls, respectively, p < 0.05). No significant relationship between hair whorl position on either scale and flight speed was found, indicating that the association between whorl position and temperament seems to be sensitive to the precise context in which temperament is measured and, in addition, we found no link with weight gain. The value of hair whorl position as a potential indicator trait in selection against flighty temperaments in frequently handled cattle therefore seems to be limited. The causative mechanism linking hair patterning and behavioural expression in apparently normally developed cattle is uncertain and should be understood before the use of hair whorls in selective breeding could be advocated.

Genetics of flight time and other measures of temperament and their value as selection criteria for improving meat quality traits in tropically adapted breeds of beef cattle

Flight time, an objective measure of temperament, was recorded in 3594 Brahman, Belmont Red, and Santa Gertrudis heifers and steers. Two subjective measures of temperament (crush score and flight speed score) were also available for over 2000 of these animals. Temperament measures were recorded post-weaning (average age 8 months) and again at the start of finishing (average age 19 months) on a subset of the animals. Nine meat quality traits were measured on these animals and included measures on 2 different muscles [M. longissimus thoracis et lumborum (LTL) and M. semitendinosus (ST)]. The heritability of flight time measured post-weaning and at the start of finishing was 0.30 and 0.34, respectively, with a repeatability of 0.46 across the measurement times. Heritabilities for scored temperament traits were 0.21, 0.19, and 0.15 for post-weaning flight speed score, post-weaning crush score, and start of finishing crush score, respectively. Genetic correlations across measurement times for flight time were 0.98 and 0.96 for crush score, indicating a strong underlying genetic basis of these temperament measures over time; however, the corresponding phenotypic correlations were lower (0.48 and 0.37, respectively). Longer flight times (i.e. better temperament) were genetically correlated with improved tenderness (i.e. lower shear force and higher tenderness scores), with genetic correlations of –0.42 and 0.33 between LTL shear force, and Meat Standards Australia (MSA) tenderness, respectively. Genetic correlations between post-weaning crush score and the same meat quality traits were 0.39 and –0.47, respectively. However, genetic and phenotypic correlations between measures of temperament and other meat quality traits were generally low, with the exception of crush scores with LTL Minolta a* value (–0.37 and –0.63 for post-weaning and start of finishing measurement time, respectively). Predicted correlated responses of –0.17 kg LTL shear force and 2.6 MSA tenderness points per generation were predicted based on the genetic parameter estimates and a recording regime of both flight time and crush scores. Selection based on the measures of temperament described in this study could be used to improve temperament itself and correlated improvements can also occur in meat tenderness and eating quality traits in tropically adapted breeds of cattle.

Genetic and environmental factors affecting temperament of zebu and zebu-derived beef cattle grazed at pasture in the tropics

Separate experiments were conducted in 2 zebu-derived herds grazed at pasture in the dry tropics of Central Queensland, to determine genetic and environmental effects on At Duckponds, temperament of crossbreed steers and heifers from 2 calf crops was assessed using an objective flight speed score and 2 subjective scores (a visual flight speed score and a crush score) to determine whether the subjective tests were useful as selection criteria for on-farm selection programs. At Belmont, temperament of bull and heifer calves from 7 calf crops was measured by recording objective flight speed scores of individual animals at weaning (6 months), 12 months, and 18 months. At Duckponds, heritabilities of average objective flight speed, visual flight speed, and crush scores were 0.35, 0.08, and 0.30, respectively. Phenotypic and genetic correlations between the different measures of temperament were moderate to low. Based on low correlations and re-ranking of fixed effect classes that occurred between subjective tests, it was concluded the subjective tests were not sufficiently correlated with the objective measure to justify their use. The objective flight speed score is recommended as the test of choice for use in breeding programs using Bos indicus or Bos indicus derived animals. At Belmont, even a single flight speed score was moderately heritable, but use of the average of 2 or 3 repeated flight speed scores substantially increased heritability. The realised heritability of average flight speed score was 0.48, almost identical to the estimated heritability of average flight speed score of 0.50. Direct responses to a single generation of divergent selection for single flight speed scores at different ages demonstrated that selection for flight speed was effective in modifying flight speed scores of progeny. Correlated responses to divergent selection for flight speed scores indicated that, under extensive grazing systems, the economic value of temperament arose mainly through a reduction in production costs. There were significant differences in temperament scores between sire breeds used in the crossbreeding experiment at Duckponds, but there were no differences between lines at Belmont. From these results, it is possible that Continental breeds either have specific, negative combining ability when crossed with Brahmans, or themselves have temperaments that are no better than those of Bos indicus. Treatment to control gastrointestinal parasites (worms) had a significant (P &lt; 0.001) negative effect on flight speed.

Associations between temperament, performance and immune function in cattle entering a commercial feedlot

Behavioural, endocrine and immunological measures made at weaning or feedlot entry were examined for associations amongst them and with feedlot performance with a view to identifying predictors of the suitability of cattle for feedlot finishing. The 24 animals used in this experiment were chosen to represent the extremes of temperament amongst 209 beef steer calves that were weaned at 7–9 months of age. From a subgroup of 50 animals that were paddock-weaned without handling or supplementary feeding, the 12 animals with the worst temperament were selected on the basis of flight time and crush behaviour assessment. From a matched subgroup of 100 animals that were weaned in yards and hand fed for 10 days, the 12 animals with the best temperament were selected on the basis of flight time, crush score and a novel behavioural test performed as follows. Each morning, fresh hay and a small amount of grain were offered in an adjacent pen and calves were scored on their willingness to walk past an observer standing by the gateway between the 2 pens. These 2 experimental groups were designated as ‘nervous’ and ‘calm’, respectively. Blood samples were collected at the start and end of weaning for cortisol assay. On entry to a commercial feedlot 6 months later, blood samples were collected for cortisol and immunological assays on day 1 (immediately after induction processing) and day 5 (after 4 days in the feedlot pen). The nervous group had significantly higher cortisol levels at weaning and at the feedlot and, after 85 days on feed, had significantly lower average daily gain and significantly higher morbidity than the calm group. Groups did not differ in total and differential leucocyte counts, lymphocyte proliferation, production of the cytokine interferon, natural killer cell activity, neutrophil myeloperoxidase activity, lymphocyte subsets (CD4, CD8 or WC1), and serum concentrations of IgA, but IgM was lower in the calm group. Significant correlations were found between cortisol and a number of haematological variables, flight time, and average daily gain. The correlations suggest that desirable traits at feedlot entry may include slow flight time, low crush score and high confidence score, low cortisol, low total white cell count, low neutrophil count, high CD8 + lymphocyte percentage, high lymphocyte proliferative activity and high IgA concentration. Relationships between behavioural traits and immunological measures may have utility in predicting the suitability of individuals for the feedlot environment.