Is the temperament of crossbred dairy cows related to milk cortisol and oxytocin concentrations, milk yield, and quality?

Reactive dairy cows are more susceptible to stress, and this may result in negative effects on milk yield and quality. The aims of this study were to investigate the relationships between temperament traits and concentration of milk cortisol and oxytocin, milk yield, milkability, and milk quality in Holstein-Gyr cows. Temperament traits were assessed in 76 Holstein-Gyr cows in the milking parlor (by scoring milking reactivity and recording the numbers of steps and kicks during pre-milking udder preparation and when fitting the milking cluster) and during handling in the corral (by measuring the time to enter in the squeeze chute, ET and flight speed, FS). Milk samples were collected for milk quality (% fat, % protein, % lactose, and somatic cell count, SCC), and milk cortisol and oxytocin. Milk yield, milking time, and average flow were also measured. The calmer cows during milking management (class 'low') produced milk with higher protein (p = 0.028) content and tendencies for lower fat (p = 0.056) and higher lactose (p = 0.055) contents. Regarding the hormones, the most reactive cows (class 'high') in the milking and handling corral produced milk with higher concentrations of cortisol (p<0.001) and oxytocin (p = 0.023). In addition, the temperament of the animals affected some of the productive measures evaluated. Cows with reactive temperament had lower milk flow and longer milking time than the intermediate ones and had higher fat and a tendency for lower protein percentage in milk compared to cows with intermediate temperaments. Calm and intermediate cows in the handling corral produced more milk and presented better milkability parameters, such as a shorter milking time and greater average milk flow. Our results suggest that the cows' behavioral reactivity can be related to the intensity of their response to stress during handling.

Flunixin Meglumine Is Superior to Meloxicam for Providing Analgesia after Surgical Castration in 2-Month-Old Goats.

Farm animals are exposed to various painful procedures during their productive lives, making it necessary to implement anesthetic and analgesic protocols. However, there are few studies evaluating the effectiveness of these drugs. Our objective was to compare the analgesic effects of two nonsteroidal anti-inflammatory drugs (NSAIDs): meloxicam (MEL) and flunixin meglumine (FLU), in goat kids subjected to surgical castration under local anesthesia. Anglo-Nubian goat kids (60 days old) were allocated into two groups: MEL (n = 9), and FLU (n = 8), each administered 5 min before starting castration. All had been previously subjected to local anesthesia with lidocaine, injected bilaterally into the testes, plus subcutaneous in the scrotal raphe. Pain sensitivity was evaluated using the von Frey monofilaments test. Reactions were recorded before castration (M0), immediately after castration (M1), and once-daily for three consecutive days post-castration (M2, M3, and M4, respectively). Pain assessments were conducted in three body regions: at four points of the scrotum (dorsal and ventral; left and right lateral; R1); medial region of the pelvic limb, gracilis muscle (R2); and hypogastric region of the abdomen (R3). MEL goats had considerably greater pain reaction in R1 and R2 over time, mainly in M2; therefore, FLU was a more effective analgesic than MEL, resulting in less pain reaction.

Limited Effects of Pain Control Treatments on Behaviour and Weight Gain of Pure and Crossbred Nellore Heifer Calves When Subjected to Hot-Iron Branding.

Hot-iron branding is still commonly performed in cattle farming in tropical countries, and possibly has negative consequences for animal welfare and weight gain. This study examined the behavioural and weight gain responses of pure and crossbred Nellore heifer calves subjected to hot-iron branding on the cheek, without and with use of anaesthesia and analgesia. Ninety-two heifer calves, around 120 days old, were studied prospectively when subjected to hot-iron branding on the cheek (a statutory procedure in Brazil following brucellosis vaccination). Four randomly selected groups of calves were allocated to four treatments: no pain control (CO); subcutaneous anaesthetic local block (LA); intramuscular analgesia (meloxicam) (LT); and local anaesthesia plus meloxicam (LL). Behaviour, flight speed and body weight were evaluated before, during, and five (5-d) and 60 days (60-d) after branding. For these parameters, the only difference observed was higher tension in the CO group 5-d post-branding, suggesting a short-term negative effect of branding without pain control. The limited effects of the pain control treatments suggest interference in pain assessment by other factors, such as expression of fear and stress. Despite the lack of differences observed in behaviour and production parameters, facial hot-iron branding is an obvious welfare issue and, due to the additional handling involved, adoption of a simple pain relief protocol is not sufficient to minimise the welfare impact.

Effect of work on body language of ranch horses in Brazil.

The horses' responses to exercise are commonly monitored using physiological variables, nonetheless physical and mental states can also be expressed through body language. The aims of this study were: (i) to identify how facial expressions and other behavioural variables change in ranch horses after a routine workday, and (ii) to investigate if these changes can be used as indicators of physical tiredness by relating them to known variables of physical fitness and workload. Fourteen crossbred ranch horses were assessed pre- and post-workday on two farms, recording the body language, physiological and workload variables. Statistical analysis consisted of four stages: (i) comparisons between the sampling times (pre- vs post-workday) using linear mixed-effects models with repeated measures and a paired Wilcoxon test; (ii) selection of the most powerful variables by applying Kaiser-Meyer-Olkin test and principal components analyses (PCA); (iii) evaluations of the relationships within these selected variables utilizing PCA and Spearman rank coefficients; and (iv) identifying a critical level of the most robust behavioural indicators using a non-hierarchical cluster analysis. Results showed that after a workday the horses increased the frequency/duration of body language indicative of resting. They also decreased the frequency/duration of body language indicative of attention and movements to avoid flies. However, some of these behaviours are also shown when horses are in pain, leading us to suggest that some ranch horses were probably experiencing a combination of of tiredness and slight soreness. Of particular interest, because of the ease with which it can be assessed on the farm and generalized to other situations, we suggest that the frequency of shifting weight between the forelegs has potential to be used as an indicator of physical tiredness in horses. The results can also be used in the development of tools to improve the welfare of ranch horses as well as horses used in other activities, although more research is needed to validate this assumption.

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.

Effectiveness of pneumatically powered penetrating and non-penetrating captive bolts in stunning cattle.

This study assessed the effectiveness of penetrating (PCB; 190 psi; N = 363) and non-penetrating captive bolt guns (NPCB; 210-220 psi; N = 92) to stun a total of 455 cattle (Zebu and Zebu Cross). Physical bolt parameters (momentum, kinetic energy and energy density) were evaluated. Clinical indicators of brain function were recorded after stunning (GR), after being hoisted (HO) and at the bleeding rail (BL). Physical bolt parameters (bolt velocity, momentum, kinetic energy, energy density and sectional density) were significantly higher (P < 0.001) for PCB. The need for two or more shots was more frequent for NPCB (210-220 psi; 29% vs. 12%, P < 0.001). Cattle were more likely to collapse at first shot with PCB (190 psi; 99%) compared to NPCB (91%; P < 0.002) which can be attributed to the higher values of bolt physical parameters. Incidence of eyeball rotation (5% vs. 1%) and righting behaviour (7% vs. 1%) were higher (P < 0.001) for NPCB (210-220 psi) at GR than PCB. The NPCB with 210-220 psi had a higher frequency of response to nostril stimulation (2% vs. 0%; P < 0.001) than PCB. Rhythmic respiration was more frequently found for NPCB with 210-220 psi at GR, HO and BL. Therefore, PCB with 190 psi was more effective in ensuring unconsciousness in cattle.

Efficiency of low versus high airline pressure in stunning cattle with a pneumatically powered penetrating captive bolt gun.

The efficiency of stunning cattle was assessed in 443 animals (304 pure Zebu and 139 crossbred cattle), being mainly mature bulls and cows. Cattle were stunned using a Jarvis pneumatically powered penetrating captive bolt gun operating with low (160-175psi, N=82) and high (190psi, N=363) airline pressure, which was within the manufactures specifications. Signs of brain function and the position of the shots on the heads were recorded after stunning. Velocity of the captive bolt and its physical parameters were calculated. Cattle shot with low pressures showed more rhythmic respiration (27 vs. 8%, P<0.001), less tongue protrusion (4 vs. 12%, P=0.03) and less masseter relaxation (22 vs. 48%, P<0.001). There was an increased frequency of shots in the ideal position when cattle were shot with the low compared to high airline pressures (15.3 vs. 3.1%). Bolt velocity and its physical parameters were significantly (P<0.01) higher when using high pressure. Airline pressures below 190psi are inappropriate when shooting adult Zebu beef cattle with pneumatically powered penetrating captive bolt guns.

Long-term effects of good handling practices during the pre-weaning period of crossbred dairy heifer calves.

The aim of this study was to determine whether applying good practices of handling during the pre-weaning period have long-term effects on behavioral and physiological indicators, health status, and average daily gain (ADG) of crossbred Bos taurus × Bos indicus heifer calves. During the pre-weaning period, 98 crossbred of Holstein × Gir heifer calves were allotted into three treatments: (1) good practices of handling + brushing (GPB; n = 25), (2) good practices of handling (GP; n = 25), and (3) control (n = 48). Every 2 months, four evaluation periods (EV1 to EV4) were conducted to record data. Behavioral indicators comprised time to drive (TD), flight speed (FS), flight distance (FD), and composite reactivity score (CRS). Physiological indicators of acute stress during handling comprised respiratory and heart rates. Health status comprised data regarding occurrence of most common diseases (i.e., pneumonia and anaplasmosis). Collected data were analyzed by using a linear mixed model for repeated measures, Tukey's test, and chi-squared procedures. Treatment influenced (P < 0.05) TD, FS, and FD but not CRS (P = 0.78). From EV1 to EV3, the control calves had the lowest TD. The GPB group had lower FS than the control but did not differ from GP. The GPB group had lower FD means than the other two groups in EV2, EV3, and EV4. No differences (P > 0.05) due to treatment were observed on heart and respiratory rates, ADG, or occurrence of pneumonia and anaplasmosis. It was concluded that adoption of good practices of handling during pre-weaning period may lead to long-term positive effects.

Genome-Wide Association Study between Single Nucleotide Polymorphisms and Flight Speed in Nellore Cattle.

INTRODUCTION: Cattle temperament is an important factor that affects the profitability of beef cattle enterprises, due to its relationship with productivity traits, animal welfare and labor safety. Temperament is a complex phenotype often assessed by measuring a series of behavioral traits, which result from the effects of multiple environmental and genetic factors, and their interactions. The aims of this study were to perform a genome-wide association study and detect genomic regions, potential candidate genes and their biological mechanisms underlying temperament, measured by flight speed (FS) test in Nellore cattle. MATERIALS AND METHODS: The genome-wide association study (GWAS) was performed using a single-step procedure (ssGBLUP) which combined simultaneously all 16,600 phenotypes from genotyped and non-genotyped animals, full pedigree information of 162,645 animals and 1,384 genotyped animals in one step. The animals were genotyped with High Density Bovine SNP BeadChip which contains 777,962 SNP markers. After quality control (QC) a total of 455,374 SNPs remained. RESULTS: Heritability estimated for FS was 0.21 ± 0.02. Consecutive SNPs explaining 1% or more of the total additive genetic variance were considered as windows associated with FS. Nine candidate regions located on eight different Bos taurus chromosomes (BTA) (1 at 73 Mb, 2 at 65 Mb, 5 at 22 Mb and 119 Mb, 9 at 98 Mb, 11 at 67 Mb, 15 at 16 Mb, 17 at 63 Kb, and 26 at 47 Mb) were identified. The candidate genes identified in these regions were NCKAP5 (BTA2), PARK2 (BTA9), ANTXR1 (BTA11), GUCY1A2 (BTA15), CPE (BTA17) and DOCK1 (BTA26). Among these genes PARK2, GUCY1A2, CPE and DOCK1 are related to dopaminergic system, memory formation, biosynthesis of peptide hormone and neurotransmitter and brain development, respectively. CONCLUSIONS: Our findings allowed us to identify nine genomic regions (SNP windows) associated with beef cattle temperament, measured by FS test. Within these windows, six promising candidate genes and their biological functions were identified. These results may contribute to a better comprehension into the genetic control of temperament expression in Nellore cattle.