Are dairy cows with a more reactive temperament less efficient in energetic metabolism and do they produce more enteric methane?

It remains unknown whether dairy cows with more reactive temperament produce more enteric methane (CH4) and are less bioenergetically efficient than the calmer ones. The objectives of this study were (a) to evaluate the relationship between cattle temperament assessed by traditionally used tests with energetic metabolism and enteric CH4 emissions by crossbred dairy cows; (b) to assess how cows' restlessness in respiration chambers affects energetic metabolism and enteric CH4 emissions. Temperament indicators were evaluated for 28 primiparous F1 Holstein-Gyr cows tested singly in the handling corral (entrance time, crush score, flight speed, and flight distance) and during milking (steps, kicks, defecation, rumination, and kick the milking cluster off). Cows' behaviors within respiration chambers were also recorded for each individual kept singly. Digestibility and calorimetry trials were performed to obtain energy partitioning and CH4 measures. Cows with more reactive temperament in milking (the ones that kicked the milking cluster off more frequently) spent 25.24% less net energy on lactation (P = 0.04) and emitted 36.77% more enteric CH4/kg of milk (P = 0.03). Furthermore, cows that showed a higher frequency of rumination at milking parlor allocated 57.93% more net energy for milk production (P < 0.01), spent 50.00% more metabolizable energy for milk production (P < 0.01) and 37.10% less CH4/kg of milk (P = 0.04). Regarding the handling temperament, most reactive cows according to flight speed, lost 29.16% less energy as urine (P = 0.05) and tended to have 14.30% more enteric CH4 production (P = 0.08), as well as cows with a lower entrance time (most reactive) that also lost 13.29% more energy as enteric CH4 (P = 0.04). Temperament and restless behavior of Holstein-Gyr cows were related to metabolic efficiency and enteric CH4 emissions. Cows' reactivity and rumination in the milking parlor, in addition to flight speed and entrance time in the squeeze chute during handling in the corral, could be useful measures to predict animals more prone to metabolic inefficiency, which could negatively affect the sustainability of dairy systems.

Reduced space in outdoor feedlot impacts beef cattle welfare.

There is a trend to reduce the space allowance per animal in cattle feedlot, despite its potential negative impact on animal welfare. Aiming to evaluate the effects of space allowance per animal in outdoor feedlots on beef cattle welfare, a total of 1350 Nellore bulls (450 pure and 900 crossbred) were confined for 12 weeks using three space allowances: 6 (SA6), 12 (SA12) and 24 (SA24) m2/animal (n = 450 per treatment). Bulls were housed in three pens per treatment (n = 150 per pen). The first 6 weeks in the feedlot were defined as 'dry' and the last as 'rainy' period, according to the accumulated precipitation. Animal-based (body cleanliness, health indicators and maintenance behaviour) and environmental-based indicators (mud depth and air dust concentration) were assessed weekly during the feedlot period. Most of the health indicators (nasal and ocular discharge, hoof and locomotion alterations, diarrhoea, bloated rumen and breathing difficulty) were assessed in a subset of 15 animals randomly selected from each pen. Coughs and sneezes were counted in each pen. Maintenance behaviours (number of animals lying and attending the feed bunk) were recorded with scan sampling and instantaneous recording at 20-min intervals. Postmortem assessments were carried out in all animals by recording the frequencies of macroscopic signs of bronchitis, pulmonary emphysema, nephritis and urinary cyst and by measuring the weight and cortical and medullar areas of adrenal glands (n = 30 per pen). Compared with SA12 and SA24, SA6 showed a greater number of sneezes per minute during the dry period and a greater percentage of animals with locomotion alterations during the rainy period. Coughing, diarrhoea and nasal discharge affected a larger number of animals in the SA6 relative to the other two groups. During the rainy period, there was a lower percentage of animals with nasal and ocular discharge, and a greater percentage of animals with abnormal hoof and lying. A lower percentage of animals in SA6 and SA12 (but not SA24) attended the feed bunk during the rainy relative to the dry period. A mud depth score of 0 (no mud) was most frequent in SA24 pens, followed by SA12 and then SA6. Adrenal gland weight and cortical area were lower in SA24 animals compared with those in SA6 and SA12. The results show that decreasing the space allowance for beef cattle in outdoor feedlots degrades the feedlot environment and impoverishes animal welfare.

Blood Glucose Concentrations in Nicarbazin-Fed Broiler Chickens.

Four floor pen studies were carried out to evaluate the effects of nicarbazin (NIC) administration on blood glucose concentrations and the onset of hypoglycemia in broiler chickens. All tests involved continuous NIC feeding at 0, 100, or 125 ppm to 28 days of age. In each study, birds were reared at both standard environmental temperatures and at 3 C below this level. In addition, two studies were conducted in the presence of coccidial infection and two were carried out in noninfected broilers. At 26 days of age in each test, two birds per pen were bled by puncture of the brachial vein, and whole blood glucose concentrations were determined. Results indicated that the administration of NIC to broilers for 26 days had no effect on blood glucose concentrations, although graded levels of NIC tended to increase these values. In addition, no evidence of hypoglycemia was recorded in any of the trials. In a similar fashion, blood glucose was unaffected by environmental temperature and coccidial challenge. These findings support previous work showing that NIC administration does not influence blood glucose levels and indicate that the product is not involved when field diagnoses use reduced blood glucose and hypoglycemia as indicators of production anomalies.

Evaluation of starter dietary digestible lysine level on broilers raised under a sex-separated or straight-run housing regime, part 2: Economics of sex separation and digestible lysine level for maximum returns.

The objective of this experiment was to determine the maximum net returns digestible lysine (dLys) levels (MNRL) when maintaining the ideal amino acid ratio for starter diets of broilers raised sex separate or comingled (straight-run). A total of 3,240 Ross 708 chicks was separated by sex and placed in 90 pens by 2 rearing types: sex separate (36 males or 36 females) or straight-run (18 males + 18 females). Each rearing type was fed 6 starter diets (25 d) formulated to have dLys levels between 1.05 and 1.80%. A common grower diet with 1.02% of dLys was fed from 25 to 32 days. Body weight gain (BWG) and feed intake were assessed at 25 and 32 d for performance evaluation. Additionally, at 26 and 33 d, 4 birds per pen were sampled for carcass yield evaluation. Data were modeled using response surface methodology in order to estimate feed intake and whole carcass weight at 1,600 g live BW. Returns over feed cost were estimated for a 1.8-million-broiler complex of each rearing system under 9 feed/meat price scenarios. Results indicated that females needed more feed to reach market weight, followed by straight-run birds, and then males. At medium meat and feed prices, female birds had MNRL at 1.07% dLys, whereas straight-run and males had MNRL at 1.05%. As feed and meat prices increased, females had MNRL increased up to 1.15% dLys. Sex separation resulted in increased revenue under certain feed and meat prices, and before sex separation cost was deducted. When the sexing cost was subtracted from the returns, sex separation was not shown to be economically viable when targeting birds for light market BW.

Performance and anticoccidial effects of nicarbazin-fed broilers reared at standard or reduced environmental temperatures.

A series of 4 floor pen studies was conducted to evaluate the effects of environmental temperature modification on nicarbazin (NIC) responses in broiler chickens raised to 28 d of age. Birds were reared at either standard temperatures (recommended by the primary breeder for ages zero to 28 d) or at 3°C below this level. From placement to 28 d, birds were provided feeds containing zero, 100, or 125 ppm NIC, comprising a 2 × 3 factorial arrangement in each test. Two of the trials were conducted in the presence of an imposed coccidial challenge and 2 were conducted in healthy animals. At 18 and 28 d of age, performance was recorded; cloacal temperatures were measured at 7, 14, 21, and 26 days. Mortality data were collected daily and coccidial lesions were scored at 6 d post challenge. Results of these studies revealed that NIC improved coccidial lesion scores regardless of environmental temperature. In the absence of coccidial challenge, NIC depressed performance, but reductions in environmental temperature diminished the magnitude of these responses. Under conditions of coccidial challenge, NIC significantly improved body weight gains in both temperature environments. Compared to standard temperature conditions, lower environmental temperatures exerted a positive effect on feed conversion rates of NIC-fed broilers. Birds reared in the low temperature environment exhibited lower cloacal temperatures than standard environment groups throughout the test period. Irrespective of coccidial challenge, lower environmental temperatures significantly reduced nicarbazin mortality compared to standard temperature groups, resulting in a significant nicarbazin x temperature interaction. This finding indicates that temperature modification is a practical method for minimizing mortality over the course of 28-day nicarbazin usage.

Straight-run vs. sex separate rearing for two broiler genetic lines Part 2: Economic analysis and processing advantages.

The objective of this analysis was to evaluate the effects of raising broilers under sex separate and straight-run conditions for 2 broiler genetic lines. One-day-old Ross 308 and Ross 708 chicks (n = 1,344) were sex separated and placed in 48 pens according to rearing type: sex separate (28 males or 28 females) or straight-run (14 males + 14 females). There were 3 dietary phases: starter (zero to 17 d), grower (17 to 32 d), and finisher (32 to 48 d). Bird individual BW and group feed intakes were measured at 12, 17, 25, 32, 42, and 48 d to evaluate performance. At 33, 43, and 49 d 4 birds per pen (straight-run pens 2 males + 2 females) were sampled for carcass yield evaluation. Data were analyzed using linear and non-linear regression in order to estimate feed intake and cut-up weights at 3 separate market weights (1,700, 2,700, and 3,700 g). Returns over feed cost were estimated for a 1.8 million broiler complex for each rearing system and under 9 feed/meat price scenarios. Overall, rearing birds that were sex separated resulted in extra income that ranged from ${\$}$48,824 to ${\$}$330,300 per week, depending on the market targeted and feed and meat price scenarios. Sex separation was shown to be especially important in disadvantageous scenarios in which feed prices were high. Gains from sex separation were markedly higher for the Ross 708 than for the Ross 308 broilers. Bird variability also was evaluated at the 3 separate market ages under narrow ranges of BW that were targeted. Straight-run birds decreased the number of birds present in the desired range. Depending on market weight, straight-run rearing resulted in 9.1 to 16.6% fewer birds than sex separate rearing to meet marketing goals. It was concluded that sex separation can result in increased company profitability and have possible beneficial effects at the processing plant due to increased bird uniformity.

Straight-run vs. sex separate rearing for 2 broiler genetic lines Part 1: Live production parameters, carcass yield, and feeding behavior.

The objective of this experiment was to evaluate the effects of raising broilers under sex separate and straight-run conditions for 2 broiler strains. Day-old Ross 308 and Ross 708 chicks (n = 1,344) were separated by sex and placed in 48 pens according to the rearing type: sex separate (28 males or 28 females) or straight-run (14 males + 14 females). There were 3 dietary phases: starter (zero to 17 d), grower (17 to 32 d), and finisher (32 to 48 d). Birds' individual BW and feed intakes were measured at 12, 17, 25, 32, 42, and 48 d to evaluate performance. At 33, 43, and 49 d, 4 birds per pen were sampled for carcass yield evaluation. Additionally, from 06:00 to 06:30, 13:00 to 13:30, and 22:00 to 22:30, video records were taken to assess behavior at 45 days. Data were analyzed as CRD with a 2 × 3 factorial arrangement of treatments over time. Throughout the experiment Ross 308 were heavier than the 708, and after 17 d, male pens had the heavier birds, followed by straight-run and then females. Straight-run pens had higher BW CV in comparison with sex separate pens. Sex separate male BW was negatively impacted from 17 to 32 days. On the other hand, females raised sex separate were heavier than females raised straight-run with lower CV from 25 to 41 days. Post 25 d, FCR was the lowest in male pens whereas feed intake was the highest for these pens after 17 days. Overall, males had total carcass cut-up weights higher than straight-run and females at the 3 processing times. The Ross 708 had higher white meat yields, whereas 308 had higher yields for dark meat. Feeding behavior results were not consistent over time. However, from 13:00 to 13:30, birds in female pens spent more time eating, followed by straight-run and then males. In conclusion, raising females in a straight-run system negatively impacted performance and CV, whereas males benefited from straight-run rearing, with the differences being possibly related to feeder space competition.

Genetic parameter estimates for prenatal and postnatal mortality in Nellore cattle.

The aim of this study was to estimate genetic parameters for prenatal (PRE) and postnatal (POS) mortality in Nellore cattle. A total of 13 141 (PRE) and 17 818 (POS) records from Nellore females were used. PRE and POS were recorded using binary scale scores: a score of '1' was given to calves that were born alive (PRE) and those that were alive at weaning (POS), and a score of '0' was given to calves that were not alive at or around birth (PRE), as well as to those weighed at birth but not at weaning (POS). The relationship matrix included 698 sires, 107 paternal grandsires and 69 maternal grandsires. Data were analysed using Bayesian inference and a sire-maternal grandsire threshold model, including contemporary groups as random effects, and the classes of dam age at the beginning of mating season (for PRE), and dam age at calving and birthweight (linear covariable) (for POS), as fixed effects. For both traits, the covariance between direct and maternal effects (rD,M ) was estimated (rD,M ≠ 0) or fixed at zero (rD,M  = 0). PRE and POS rates were 3.00 and 4.04%, respectively. Estimates of direct and maternal heritability were 0.07 and 0.17, respectively, for PRE, and 0.02 and 0.07, respectively, for POS, assuming rD,M  = 0. For rD,M  ≠ 0, these estimates were 0.07 and 0.12, respectively, for PRE, and 0.03 and 0.07, respectively, for POS. The correlation estimates between direct and maternal effects were -0.71 (PRE) and -0.33 (POS). PRE and POS show low genetic variability, indicating that these traits probably suffer major environmental influences. Additionally, our study shows that the maternal genetic component affects preweaning calf mortality twice as much (or more) as the direct genetic component. A large number of offspring per sire is necessary in progeny tests to genetically decrease calf mortality.

Pathogeny of Fatigued Walking Condition in Pekin Ducks.

Fatigued walking condition (FWC) in ducks is an important welfare and processing issue during the loading/unloading to the processing plant that can be related to heart and bone development. An experiment was conducted to evaluate the effects of incubation conditions on duck embryo bone and heart development and their subsequent effects on ducks showing FWC at market age. Four groups of 2500 Pekin duck eggs were subjected to combinations of two incubation temperature profiles (elevated [E] and normal [N]) and two eggshell conductance profiles (G) (reduced [GR] and normal [GN]). At hatch 10 ducklings from each treatment combination were sampled for heart, liver, residual yolk, and total body weight as well as relative weights (organ percentage of whole body weight). Femur, tibia, and tarsus length and weight were also obtained, and relative asymmetry (RA) was calculated for each leg section. At 35 days of age during unloading of the truck at the slaughter plant, five hens and five drakes demonstrating normal walking and FWC were sampled. Body, heart, and ventricular weights were obtained along with femur, tibia and tarsus length, weight, and RA. Bone strength was evaluated using a three-point bending test, and tibia ash content was assessed. At hatch duckling bone characteristics and organ weights were found to be primarily affected by GR conditions, while heart development in older ducks was mainly impacted by E incubation temperatures. Tibia and relative weight at 35 days were also increased by GR and E. Fatigued ducks presented heavier tibias with more RA and cortical thickness but lower ash percentage. In conclusion, the changes in bone development during incubation and posthatch life were related to duck FWC presence during transportation to the processing plant.

A note comparing the welfare of Zebu cattle following three stunning-slaughter methods.

The objective of this study was to assess welfare of cattle during bleeding after slaughter with or without stunning. A total of 434 bulls were distributed across three slaughter treatments: penetrating captive bolt stunning followed by chest sticking (PCB, N=279), non-penetrating captive bolt stunning followed by halal slaughter (NPCB, N=67) and shechita without previous stunning (SHE, N=88). Four measures of possible consciousness and return to sensibility were recorded 20 and 60 s after bleeding as welfare indicators. They were the frequencies of responses to nostril stimulation and tongue pinch, spontaneous eye blinking, and rhythmic breathing. All responses were absent in stunned cattle at both 20 and 60 s, and in SHE cattle 7, 4, 10, and 100% of the animals presented these responses, respectively. Repeat shots were required for 46% NPCB and 2% PCB (P<0.05). The application of religious slaughter without previous stunning may result in greater risk of cattle suffering, pain and distress at slaughter.

Effects of incubation temperatures and trace mineral sources on chicken live performance and footpad skin development.

One experiment was conducted to evaluate the effects of two incubation temperature profiles (TEM) and two trace mineral (TM) sources with their inclusion levels on performance and footpad skin development of Ross 708 chickens. A total of 1,000 eggs from 29-wk-old breeders were incubated following two TEM profiles: a standard (S) eggshell temperature (37.8±0.2°C) for 21 d of incubation and an early-low late-high (LH) TEM. The second profile had low (37.2±0.2°C) temperature for the first 3 d, and S until the last 3 d when eggshell temperature was 39.2±0.2°C. At hatch, 15 male and 15 female chicks from each TEM were selected, and footpads sampled. Additionally, 168 males per TEM were placed in 24 battery cages with 7 chickens each. The 48 cages were assigned to two TM dietary treatments: one with inorganic (ITM) sources of Zn (120 ppm), Cu (10 ppm), and Mn (120 ppm) and the other with chelated (CTM) mineral sources using lower inclusion levels of Zn (32 ppm), Cu (8 ppm), and Mn (32 ppm). At 7 and 21 d, BW gain and feed conversion ratio (FCR) were obtained and chicks sampled for footpads. Histological analysis assessed thickness and area ofstratus corneum(SC), epidermis, and dermis. Data were analyzed as a completely randomized block design in a 2×2 factorial arrangement of treatments with TEM and sex as main factors for hatch data and TEM and TM diets for 7 and 21 d data. The LH chicks were heavier than S chicks at hatch, but had more residual yolk. However, S TEM male chickens were heavier at 7 and 21 d. The S TEM had better FCR than LH TEM.Papillaedermis parameters at hatch were higher in the S TEM. At 7 d, SC height and area were increased by the S TEM. At 21 d CTM increased dermis height and area. In conclusion, TEM affected footpad skin development and broiler performance. Replacing ITM with reduced levels of CTM increased dermis development without affecting live performance or other skin layers.

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.

Effects of breeder feeding restriction programs and incubation temperatures on progeny footpad development.

Footpad dermatitis begins early in life, and there is evidence of individual susceptibility. An experiment was conducted to evaluate the carryover effects of breeder feed restriction programs and incubation temperatures (TEM) on progeny footpad development at hatch, and 7 and 22 d. Cobb 500 fast feathering breeders were subjected to 2 dietary feed restriction programs during rearing: skip-a-day (SAD) and every-day feeding (EDF). At 60 wk of age, eggs from each group were collected and incubated according to 2 TEM, standard (S) eggshell temperature (38.1°C) and early-low late-high (LH). This second profile had low (36.9°C) eggshell temperature for the first 3 d, and standard temperature until the last 3 d when eggs were subjected to elevated (38.9°C) eggshell temperature. At hatch, 15 chicks from each treatment combination were sampled to obtain footpads for histological analysis. Seventy-two chicks per treatment were placed in 48 cages (6/cage), and raised to 22 d. At 7 and 22 d, 1 and 2 chickens, respectively, were sampled for footpads. The BW and group feed intake were recorded to obtain BW gain and feed conversion ratio at 7 and 21 d. Histological analysis assessed thickness and total area of stratus corneum (SC), epidermis, and dermis, and total papillae height. Data were analyzed as randomized complete block design in a 2 × 2 factorial arrangement of treatments. There was a negative effect of LH TEM on performance at both ages. An interaction effect on SC area and papillae height was observed at hatch. Additionally, SAD treatment increased thickness and area of footpad dermis. At 7 d, the SC parameters of the SAD progeny were increased. Epidermis thickness was affected by treatment interaction. Furthermore, LH TEM decreased epidermis thickness and dermis area. At 22 d, interaction effects were observed in thickness and area of SC and epidermis. Incubation S TEM increased thickness and area of dermis. It was concluded that breeder feed restriction programs and incubation TEM profiles may have carryover effects on histomorphological traits of footpads.

Genetic variability for temperament indicators of Nellore cattle.

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.

The presence of black vultures at the calving sites and its effects on cows' and calves' behaviour immediately following parturition.

Black vultures (Coragyps atratus) are often present near calving sites, and under this situation they may play a positive role by removing animal carcasses and afterbirth or a negative role by attacking neonate calves or disturbing cow-calf behaviours following parturition. Cow-calf behaviour was recorded over a 4-year study period from a total of 300 births involving 200 Nellore, 54 Guzerat, 20 Gyr and 26 Caracu cows. The calving site in relation to the location of the herd, considering cow-calf pairs within, close or distant to the herd, the presence of vultures and the behaviour of cows and calves were recorded instantaneously, at 5-min interval. On average, vultures were present at 80% of the calving sites. The frequency of vultures present at calving sites was dependent on the years for the Nellore herd, increasing from 1998 to 2003. When vultures were present, the time that the cow was in contact with its calf decreased, and the percentage of time that the cow was standing still increased. Vultures were observed pecking cows and their neonates during 34.1% of all recordings. However, in only two cases pecking injuries were actually observed on calves that were noted to be very weak. The preliminary results suggest that although black vultures cannot be characterized as a predator of neonate calves, they sometimes attack neonate calves and their presence near the calving sites alter the behaviours of cows and calves.

Genetic associations between flight speed and growth traits in Nellore cattle.

The aim of the present study was to estimate genetic parameters for flight speed and its association with growth traits in Nellore beef cattle. The flight speed (FS) of 7,402 yearling animals was measured, using a device composed of a pair of photoelectric cells. Time interval data (s) were converted to speed (m/s) and faster animals were regarded as more reactive. The growth traits analyzed were weaning weight (WW), ADG from weaning to yearling age, and yearling scrotal circumference (SC). The (co)variance components were estimated using REML in a multitrait analysis applying an animal model. The model included random direct additive genetic and residual effects, fixed effects of contemporary groups, age of dam (classes), and age of animal as covariable. For WW, the model also included maternal genetic and permanent environmental random effects. The direct heritability estimate for FS was 0.26 ± 0.05 and direct heritability estimates for WW, SC, and ADG were 0.30 ± 0.01, 0.48 ± 0.02, and 0.19 ± 0.01, respectively. Estimates of the genetic correlation between FS and the growth traits were -0.12 ± 0.07 (WW), -0.13 ± 0.08 (ADG), and -0.11 ± 0.07 (SC). Although the values were low, these correlations showed that animals with better temperaments (slower FS) tended to present better performance. It is possible to infer that longterm selection for weight and scrotal circumference can promote a positive genetic response in the temperament of animals. Nevertheless, to obtain faster genetic progress in temperament, it would be necessary to perform direct selection for such trait. Flight speed is an easily measured indicator of temperament and can be included as a selection criterion in breeding programs for Nellore cattle.

Lead hepatotoxicology: a study in an animal model.

The increasing use of lead (Pb) for industrial purposes has resulted in the significant increase in environmental contamination of our planet especially in concern to water and food. In this study using the electron scanning microscopy (SEM), the authors showed the effects of this metal as a result of a chronic and cumulative process. As a primary method of detection of Pb in situ, SEM was chosen, coupled with a detection system Noran Voyager of basic microanalysis X-ray (SEM-XRM), with detection system energy dispersive spectrometry. Mice BALB/c was used as a study model. An animal model of inflammation was used, that consisted in the formation of a subcutaneous pocket of air. It was observed that 75% of Pb stock was captured by the liver, the main target organ in the capture of the metal, the kidney was the second organ to capture the Pb stock and the third was the spleen. It was verified that a low deposition of Pb was found in the lungs and the brain. The main results of this study showed how Pb is captured by different organs. We also demonstrated the vulnerability to inflammation of this metal.

The relationship between dairy cow hygiene and somatic cell count in milk.

Corporal hygiene is an important indicator of welfare for dairy cows and is dependent on facilities, climate conditions, and the behavior of the animals. The objectives of this study were to describe how the hygiene conditions of dairy cows vary over time and to assess whether a relationship exists between hygiene and somatic cell count (SCC) in milk. Monthly hygiene evaluations were conducted on lactating cows in 2 dairy farms for 9 consecutive months, totaling 3,554 evaluations from 545 animals. Hygiene was measured using a 4-point scoring system (very clean, clean, dirty, and very dirty) for 4 areas of the animal's body (leg, flank, abdomen, and udder) and combining these scores to generate a composite cleanliness score. A total of 2,218 milk samples was analyzed from 404 cows to determine SCC and somatic cell linear scores (SCLS). Individual variation was observed in the hygiene of cows throughout the year, with the highest proportion of clean cows being observed in August and the lowest in January. In spite of this seasonal variation, approximately half (55.62%) of the cows displayed consistent cleanliness scores, with 45.86% of them remaining consistently clean (very clean or clean) and 9.76% remaining dirty (very dirty or dirty) over the course of the study. The very clean cows had the lowest SCLS, followed by the clean, dirty, and very dirty cows (no statistically significant differences were found between the latter 2 groups). The most critical months for cow hygiene were those with the greatest rainfall, when a reduction in the welfare of cows and higher SCC values were observed. The evaluation and control of dairy cow hygiene are useful in defining management strategies to reduce problems with milk and improve the welfare of the animals.

The state of research into children with cancer across Europe: new policies for a new decade.

Overcoming childhood cancers is critically dependent on the state of research. Understanding how, with whom and what the research community is doing with childhood cancers is essential for ensuring the evidence-based policies at national and European level to support children, their families and researchers. As part of the European Union funded EUROCANCERCOMS project to study and integrate cancer communications across Europe, we have carried out new research into the state of research in childhood cancers. We are very grateful for all the support we have received from colleagues in the European paediatric oncology community, and in particular from Edel Fitzgerald and Samira Essiaf from the SIOP Europe office. This report and the evidence-based policies that arise from it come at a important junction for Europe and its Member States. They provide a timely reminder that research into childhood cancers is critical and needs sustainable long-term support.