Using whole-genome sequence (WGS) data are supposed to be optimal for genome-wide association studies and genomic predictions. However, sequencing thousands of individuals of interest is expensive. Imputation from single nucleotide polymorphisms panels to WGS data is an attractive approach to obtain highly reliable WGS data at low cost. Here, we conducted a genotype imputation study with a combined reference panel in yellow-feather dwarf broiler population. The combined reference panel was assembled by sequencing 24 key individuals of a yellow-feather dwarf broiler population (internal reference panel) and WGS data from 311 chickens in public databases (external reference panel). Three scenarios were investigated to determine how different factors affect the accuracy of imputation from 600 K array data to WGS data, including: genotype imputation with internal, external and combined reference panels; the number of internal reference individuals in the combined reference panel; and different reference sizes and selection strategies of an external reference panel. Results showed that imputation accuracy from 600 K to WGS data were 0.834±0.012, 0.920±0.007 and 0.982±0.003 for the internal, external and combined reference panels, respectively. Increasing the reference size from 50 to 250 improved the accuracy of genotype imputation from 0.848 to 0.974 for the combined reference panel and from 0.647 to 0.917 for the external reference panel. The selection strategies for the external reference panel had no impact on the accuracy of imputation using the combined reference panel. However, if only an external reference panel with reference size >50 was used, the selection strategy of minimizing the average distance to the closest leaf had the greatest imputation accuracy compared with other methods. Generally, using a combined reference panel provided greater imputation accuracy, especially for low-frequency variants. In conclusion, the optimal imputation strategy with a combined reference panel should comprehensively consider genetic diversity of the study population, availability and properties of external reference panels, sequencing and computing costs, and frequency of imputed variants. This work sheds light on how to design and execute genotype imputation with a combined external reference panel in a livestock population.

Multiple trait selection indexes in pig breeding programmes should take into account the population structure and time delay between parent selection and expressions of traits in all production levels next to the trait impacts on economic efficiency of production systems. Gene flow procedures could be used for the correct evaluation of maternal and direct traits of pig breeds involved in breeding or crossbreeding systems. Therefore, the aim of this study was to expand a previously developed bioeconomic model and computer program to calculate the marginal economic values by including a gene flow procedure to calculate the economic weights for maternal and direct traits in pig breeds. The new program was then applied to the three-way crossbreeding system of the Czech National Programme for Pig Breeding. Using this program, the marginal economic values of traits for dam breeds Czech Large White in the dam position and Czech Landrace in the sire position, and for the sire breed Pietrain were weighted by the number of discounted gene expressions of selected parents of each breed summarised within all links of the crossbreeding system during the 8-year investment period. Economic weights calculated in this way were compared with the approximate economic weights calculated previously without a gene flow procedure. Taking into account the time delay between parent selection and trait expression (using discounting with half-year discount rates of 2% or 5%) and including more than one generation of parent progeny had little impact on the relative economic importance of maternal and direct traits of breeds involved in the evaluated three-way crossbreeding system. These results indicated that this gene-flow method could be foregone when estimating the relative economic weights of traits in pig crossbreeding systems applying artificial insemination at all production levels.

The hypothesis of the research was the assumption, that manganese nanoparticles can affect the body in the same way as macromolecules. Their smaller size and greater biological reactivity will potentially allow the Mn addition to the diet to be reduced and, consequently, less excretion of this element into the environment. The aim of the study was to determine whether the use of Mn nanoparticles would make it possible to reduce the level of this micronutrient added to turkey diets without adversely affecting redox reactions in cells and epigenetic changes. The experiment was conducted on six groups with 10 replications, in a two-factor design with three dosages of manganese: 100, 50 and 10 mg/kg, and two sources: manganese oxide (MnO) and manganese nanoparticles (NP-Mn2O3). Markers of oxidative stress determined in the blood, that is, the concentration of lipid hydroperoxides, malondialdehyde, protein carbonyl derivatives, 3-nitrotyrosine, 8-hydroxydeoxyguanosine, total glutathione, superoxide dismutase, glutathione peroxidase, catalase, ceruloplasmin, total antioxidant status, albumin and vitamin C content. The level of epigenetic changes in the blood was determined by analysing global DNA methylation. In the experiment, in which the diet of turkeys was supplemented with two forms of Mn (MnO or NP-Mn2O3) at three dosages: 100, 50 and 10 mg/kg, the 10 mg/kg dose, especially in the form of NP-Mn2O3, induced lipid oxidation reactions to the greatest extent. Irrespective of the dosage of Mn in the turkey diet, Mn in the form of NP-Mn2O3 was found to reduce protein nitration more than Mn in the form of MnO. Reducing the Mn dosage in the diet from 100 to 50 mg/kg and then to 10 mg/kg is unfavourable because proportionally increases protein and DNA oxidation in cells, decreases the activity of antioxidant enzymes, and increases the level of glutathione. Reducing the dosage from 100 to 10 mg/kg increases global DNA methylation. The reduction of the Mn level, regardless of the form used, is disadvantageous, because it weakens the defense of the antioxidant system, which consequently can induce oxidative processes in the cells. Although Mn in the form of NP-Mn2O3 reduce protein nitration better than in MnO form, the use of manganese nanoparticles in turkey feeding (even in lower doses) requires further study.

l-theanine is a unique nonproteinogenic amino acid found in tea, and has recently received considerable attention because of its various biological activities. However, there is no available research report on the use of l-theanine as a feed additive in ducks. This study was conducted to investigate the potential benefits and appropriate dosages of l-theanine on the growth performance, immune function, serum biochemical parameters, and jejunum morphology and antioxidant capacity of ducks. A total of 600 1-day-old Chaohu ducks were randomly allocated into five dietary treatment groups supplemented with 0 (control group), 300, 600, 900 and 1500 mg/kg of l-theanine. Each group included five replicates of 24 birds each. Body weight at day 28 was increased (P<0.05) by l-theanine. From days 15 to 28, l-theanine elevated cumulative BW gain (BWG) and cumulative feed intake (FI), and decreased feed to gain ratio. From days 1 to 28, l-theanine elevated (P<0.05) cumulative BWG and cumulative FI. l-theanine elevated (P<0.05) the relative weight of bursa of Fabricus (day 14), thymus (day 14), spleen (day 28) and liver (day 28). On day 28, l-theanine decreased (P<0.05) serum glucose, uric acid, triacylglycerol, total cholesterol, low-density lipoprotein cholesterol, insulin, interleukin-2 (IL-2) and IL-6 contents, and elevated (P<0.05) serum total protein, globulin (GLB), immune globulin A (IgA) and IgG contents, but only serum insulin, interferon-γ, tumor necrosis factor-α and IL-6 contents was decreased (P<0.05) and serum GLB and IgM content was elevated (P<0.05) by l-theanine on day 14. On day 14, l-theanine decreased (P<0.05) jejunum crypt depth, and elevated (P<0.05) jejunum villus height, villus height to crypt depth ratio (V/C), goblet cell number and total superoxide dismutase (T-SOD) activity. On day 28, l-theanine decreased (P<0.05) jejunum malondialdehyde content, and elevated (P<0.05) jejunum villus height, V/C, goblet cell number, and T-SOD, catalase and glutathione peroxidase activities. l-theanine levels caused quadratic effect on the growth performance, relative organ weight, serum parameters, jejunum morphology and antioxidant capacity. In conclusion, l-theanine can be used as a promising feed additive for ducks, and its optimal supplementation level was 600 to 900 mg/kg based on the current experimental condition.

In current feed evaluation systems, the nutritional value of protein sources in diets for pigs is based on the ileal digestibility of protein and amino acids, which does not account for the kinetics of protein digestion along the gastrointestinal tract. The objective of the present study was to determine the in vitro protein digestion kinetics of different protein sources (soya bean meal (SBM), wheat gluten (WG), rapeseed meal (RSM), whey powder (WP), dried porcine plasma protein, yellow meal worm larvae and black soldier fly larvae (BSF)). Protein sources were incubated with pepsin at pH 3.5 for 0 to 90 min and subsequently with pancreatin at pH 6.8 for 0 to 210 min at 39°C. The in vitro protein digestion kinetics were described as the kinetics of nitrogen (N) solubilisation and the release of low molecular weight peptides (LMW) (<500 Da). The N solubilisation rate ranged from 0.025 min−1 for BSF to 0.685 min−1 for WP during the incubation with pepsin, and from 0.027 min−1 for RSM to 0.343 min−1 for WP during the incubation with pancreatin. The release rate of LMW peptides ranged from 0.027 min−1 for WG to 0.093 min−1 for WP during the incubation with pepsin, and from 0.029 min−1 for SBM to 0.385 min−1 for WP. Black soldier fly larvae showed a similar release rate of LMW peptides as WP during the incubation with pancreatin. At the end of the sequential incubation with pepsin (90 min) and pancreatin (210 min), WG and WP showed the highest percentage of N present in LMW peptides relative to total N (78% and 79%, respectively), whereas SBM showed the lowest (35%). In conclusion, protein sources for pig diets show substantial differences in in vitro protein digestion kinetics as measured by the kinetics of N solubilisation and the release of LMW peptides. The rate of release of LMW peptides was not correlated to the rate of N solubilisation for each of the protein sources evaluated.

Optimal type and dietary inclusion rates of cereal grains for periparturient sheep are unknown. The objective was to determine effects of feeding diets with high (H) v. low (L) levels of ground corn grain (CN) v. combined ground wheat and barley grains (WB) on intake, rumen fermentation, colostrum and milk properties, and blood metabolites of periparturient sheep. Twenty Afshari×Merino ewes were used in a completely randomized design study from 24 days prepartum through 21 days postpartum. Ewes were kept indoors in individual boxes and received once daily at 0900 h total mixed rations. Treatments were mixed rations containing either (1) H or (2) L concentrate based on either (1) 100% CN or (2) 50 : 50 ratio of ground wheat : ground barley grains in a 2×2 factorial arrangement. Each treatment group had five ewes including two twin-lamb ewes and three single-lamb ewes. Postpartal dry matter intake (DMI) increased by feeding high CN v. high and low WB, while high v. low CN improved postpartum DMI. The DMI during lambing tended to increase with the high v. low WB. Feeding CN v. WB, and feeding both CN and WB at L v. H level increased fecal pH. Postpartal rumen pH was lower with the high v. low WB (5.7 v. 6.2). Rumen concentrations of propionate were lower and of acetate were higher with L v. H grain levels. Increased dietary grain reduced urine pH for WB (7.24 v. 7.83) but not for CN (7.63 v. 7.52) prepartum. Colostrum properties, postpartal urine pH, lamb weight at birth and 21 days of age, and placental weight and expulsion time were unaffected. Milk yield increased and milk fat yield tended to increase by H v. L grain diets. Plasma glucose was increased by feeding high v. low WB, whereas CN v. WB tended to reduce peripartal plasma non-esterified fatty acids (NEFA) and increased insulin to NEFA ratio. In conclusion, more cereal grains can be included in periparturient sheep diets and CN instead of WB may be fed to periparturient sheep to improve energy status. Findings suggest opportunities to optimize periparturient ewe physiology and performance through feeding certain cereals and avoiding high levels of WB.

Carbohydrate-rich diets may increase urinary excretion of chromium (Cr) and increase its requirements. This study was conducted to investigate the effect of grain type (barley v. corn) and Cr supplementation on feed intake, feeding behavior and weight gain in dairy calves. Forty-eight neonatal Holstein female calves were assigned randomly to four experimental diets in a 2×2 factorial arrangement. Experimental diets were either barley-based diet (BBD) or corn-based diet (CBD) supplemented with (+Cr) or without (−Cr) Cr as Cr-methionine (0.05 mg/kg of BW0.75). Chromium was provided in milk (from days 3 to 73 of life) during the pre-weaning period and then in pre-warmed water (from day 74 until day 94 of life) after weaning. Meal length tended to increase in calves fed the BBD v. CBD during the pre-weaning period. During the post-weaning period, meal size, inter-meal interval, and eating rate increased concurrently but meal frequency and eating time decreased in the BBD v. CBD. During the pre-weaning period, feed efficiency, BW at weaning, and heart girth increased and non-nutritive oral behaviors tended to decrease with Cr supplementation. Due to increased meal frequency, the starter feed intake but not eating time increased by Cr supplementation during the post-weaning period. Supplementing Cr increased starter feed intake, final BW, average daily gain and heart girth during the overall period. Rumination time increased in BBD+Cr calves due to increases in the frequency and duration of rumination, or decreased rumination bout interval. Overall, the type of grain had no effect on feed intake and growth performance; however, Cr supplementation decreased non-nutritive oral behaviors and increased starter feed intake via increasing the meal frequency and thereby improved growth performance.

Large efforts have been deployed in developing methods to estimate methane emissions from cattle. For large scale applications, accurate and inexpensive methane predictors are required. Within a livestock precision farming context, the objective of this work was to integrate real-time data on animal feeding behaviour with an in silico model for predicting the individual dynamic pattern of methane emission in cattle. The integration of real-time data with a mathematical model to predict variables that are not directly measured constitutes a software sensor. We developed a dynamic parsimonious grey-box model that uses as predictor variables either dry matter intake (DMI) or the intake time (IT). The model is described by ordinary differential equations.

Model building was supported by experimental data of methane emissions from respiration chambers. The data set comes from a study with finishing beef steers (cross-bred Charolais and purebred Luing finishing). Dry matter intake and IT were recorded using feed bins. For research purposes, in this work, our software sensor operated off-line. That is, the predictor variables (DMI, IT) were extracted from the recorded data (rather than from an on-line sensor). A total of 37 individual dynamic patterns of methane production were analyzed. Model performance was assessed by concordance analysis between the predicted methane output and the methane measured in respiration chambers. The model predictors DMI and IT performed similarly with a Lin’s concordance correlation coefficient (CCC) of 0.78 on average. When predicting the daily methane production, the CCC was 0.99 for both DMI and IT predictors. Consequently, on the basis of concordance analysis, our model performs very well compared with reported literature results for methane proxies and predictive models. As IT measurements are easier to obtain than DMI measurements, this study suggests that a software sensor that integrates our in silico model with a real-time sensor providing accurate IT measurements is a viable solution for predicting methane output in a large scale context.

This study examined the comminution of fresh herbage, subsequent nutrient release, and the characteristics of swallowed boli from three physically and chemically contrasting forages during ingestive mastication by dairy cows. The extent and pattern of nutrient release will determine their availability to rumen microflora, and potentially influence their efficiency of use. The forages evaluated were perennial ryegrass (ryegrass, Lolium perenne L., cv Alto AR37), lucerne (Medicago sativa L., cv Torlesse) and chicory (Cichorium intybus L., cv Choice). Experimental design was a 3×3 cross-over with three forages and three consecutive 1-day measurement periods, conducted twice. Six non-lactating, pregnant, multiparous Holstein-Friesian×Jersey cows (Bos taurus) were used, with the first cross-over applied to three mature (10.1±0.61 years old; BW 631±64 kg) cows, and the second to three young (4.8±0.02 years; BW 505±19 kg) cows. Fresh cut forage was offered to the cows following partial rumen evacuation. Swallowed boli were collected directly at the cardia at the commencement, middle and end of the first feeding bout of the first meal of the day. Forage species did not affect the fresh weight of ingested boli (mean 169 g, P=0.605) but the proportion of saliva in boli varied between forage. Boli of chicory contained the greatest amount of herbage material and least amount of saliva, whereas ryegrass boli were the opposite. Boli fresh weight tended to increase as time in the meal progressed, but the age of the cow was not shown to affect any boli characteristics or nutrient release. Particle size reduction was affected by forage, with 31%, 38% and 35% of chicory, lucerne and ryegrass herbage reduced to <2 mm. There was little evidence of relationship between comminution and any physical or chemical characteristic of the forage, except in ryegrass where extent of comminution was moderately correlated with herbage strength. Proportional release of herbage soluble carbohydrate exceeded that of N during mastication. Differences in loss of N were moderately correlated with the amount of N in the herbage (R2=0.53) but herbage comminution was not strongly correlated with release of either N or carbohydrate. These findings illustrate the complex animal×forage interactions that occur during mastication, and that it is not possible to infer nutrient loss from herbage based on herbage characteristics as the driver for this differ between species.

Sugarcane is an important forage source for dairy cows in tropical countries. However, it provides limited digestible fiber and energy intake, and fat supplementation can be a way to increase energy density and decrease dietary, non-fiber carbohydrates concentrations. We aimed to evaluate the performance, digestion and metabolism of dairy cows in early lactation fed different concentrations of soybean oil (SBO) in sugarcane-based diets. Fourteen primiparous (545±17.2 kg of BW) and eight multiparous (629±26.7 kg BW) Holstein dairy cows were used according to a randomized block design. After calving, diets were randomly assigned to cows within the two parity groups. Diets were formulated with increasing concentrations of SBO (g/kg dry matter (DM)): control (0), low (LSBO; 15.7), medium (MSBO; 44.3) and high (HSBO; 73.4). The study was performed from calving until 84 days in milk, divided into three periods of 28 days each. Dry matter intake (DMI) was affected quadratically in response to SBO addition with the greatest and lowest values of 19.0 and 16.0 kg/day for LSBO and HSBO diets, respectively. The digestibility of potentially digestible NDF was quadratically affected by SBO with the greatest value of 623 g/kg for LSBO diet. Both milk and energy-corrected milk (ECM) production were quadratically affected by SBO inclusion, with greatest ECM values of 27.9 and 27.3 for LSBO and MSBO, respectively. Soybean oil inclusion linearly decreased milk fat concentration by 13.2% from control to HSBO. The CLA t10,c12-18:2 was observed in milk fat only for MSBO and HSBO diets. Soybean oil inclusion did not affect plasma glucose or serum concentrations of total proteins, globulins, albumin, urea nitrogen, beta-hydroxybutyrate, non-esterified fatty acids or insulin. Serum concentrations of total cholesterol, triglycerides and low-density lipoprotein increased with SBO supplementation. Soybean oil inclusion in sugarcane-based diets for early lactation dairy cows from 15.7 to 44.3 g/kg DM can improve energy intake and performance; however, at 44.3 g/kg DM milk fat concentration and ECM decreased. Soybean oil inclusion at 73.4 g/kg DM adversely affected energy intake, fiber digestion and performance of early lactation dairy cows and is not recommended.

Excitable temperament disrupts physiological events required for reproductive development in cattle, but no research has investigated the impacts of temperament on growth and puberty attainment in Bos indicus females. Hence, this experiment evaluated the effects of temperament on growth, plasma cortisol concentrations and puberty attainment in B. indicus heifers. A total of 170 Nelore heifers, weaned 4 months before the beginning of this experiment (days 0 to 91), were managed in two groups of 82 and 88 heifers each (mean ± SE; initial BW=238±2 kg, initial age=369±1 days across groups). Heifer temperament was evaluated via exit velocity on day 0. Individual exit score was calculated within each group by dividing exit velocity into quintiles and assigning heifers with a score from 1 to 5 (1=slowest; 5=fastest heifer). Heifers were classified according to exit score as adequate (ADQ, n=96; exit score⩽3) or excitable temperament (EXC, n=74; exit score>3). Heifer BW, body condition score (BCS) and blood samples were obtained on days 0, 31, 60 and 91. Heifer exit velocity and score were recorded again on days 31, 60 and 91. Ovarian transrectal ultrasonography was performed on days 0 and 10, 31 and 41, 60 and 70, 81 and 91 for puberty evaluation. Heifer was declared pubertal at the first 10-day interval in which a corpus luteum was detected. Exit velocity and exit score obtained on day 0 were correlated (r⩾0.64, P<0.01) with evaluations on days 31, 60 and 91. During the experiment, ADQ had greater (P<0.01) mean BCS and BW gain, and less (P<0.01) mean plasma cortisol concentration compared with EXC heifers. Temperament × time interactions were detected (P<0.01) for exit velocity and exit score, which were always greater (P<0.01) in EXC v. ADQ heifers. A temperament × time interaction was also detected (P=0.03) for puberty attainment, which was delayed in EXC v. ADQ heifers. At the end of the experiment, a greater (P<0.01) proportion of ADQ were pubertal compared with EXC heifers. In summary, B. indicus heifers classified as EXC had reduced growth, increased plasma cortisol concentrations and hindered puberty attainment compared to ADQ heifers. Moreover, exit velocity may serve as temperament selection criteria to optimize development of B. indicus replacement heifers.

Grain-rich diets often lead to subacute ruminal acidosis (SARA) impairing rumen and systemic cattle health. Recent data suggest beneficial effects of a clay mineral (CM)- based product on the rumen microbiome of cattle during SARA. This study sought to investigate whether the CM supplementation can counteract SARA-induced perturbations of the bovine systemic health. The study used an intermittent diet-induced SARA-model with eight dry Holstein cows receiving either no additive as control or CM via concentrates (n=8 per treatment). Cows received first a forage diet (Baseline) for 1 week, followed by a 1-week SARA-challenge (SARA 1), a 1-week recovery phase (Recovery) and finally a second SARA-challenge for 2 weeks (SARA 2). Cows were monitored for feed intake, reticular pH and chewing behavior. Blood samples were taken and analyzed for metabolites related to glucose and lipid metabolism as well as liver health biomarkers. In addition, a targeted electrospray ionization-liquid chromatography-MS-based metabolomics approach was carried out on the plasma samples obtained at the end of the Baseline and SARA 1 phase. Data showed that supplementing the cows’ diet with CM improved ruminating chews per regurgitated bolus by 16% in SARA 1 (P=0.01) and enhanced the dry matter intake during the Recovery phase (P=0.05). Moreover, the SARA-induced decreases in several amino acids and phosphatidylcholines were less pronounced in cows receiving CM (P≤0.10). The CM-supplemented cows also had lower concentrations of lactate (P=0.03) and biogenic amines such as histamine and spermine (P<0.01) in the blood. In contrast, the concentration of acylcarnitines with key metabolic functions was increased in the blood of treated cows (P≤0.05). In SARA 2, the CM-cows had lower concentrations of the liver enzymes aspartate aminotransferase and γ-glutamyltransferase (P<0.05). In conclusion, the data suggest that supplementation of CM holds the potential to alleviate the negative effects of high-grain feeding in cattle by counteracting multiple SARA-induced perturbations in the systemic metabolism and liver health.

An extended milking interval of 24 h (24-h milking interval (24h-MI)) constitutes the acute phase of cow adaptation to once-daily milking (ODM). A recent trial including 724 24h-MI challenges demonstrated that milk yield responses to this acute phase of ODM are highly variable (from+22% to −52% of milk yield when switching to the 24h-MI, mean=−25.3%) and that factors such as stage of lactation parity and milk yield level influenced cows’ responses but did not account for all individual variability. Additional traits related to physiological, immune and behavioural adaptation were measured on a subset (96 observations) of this data set. This study aimed to determine (1) the relationship of these traits with cows’ milk yield responses, (2) their ability – combined with previously identified traits – to help predict milk yield responses to 24h-MI (adaptive profiles). The 24h-MI challenge consisted of three successive periods: one control week of twice-daily milking (cTDM), one single day of 24h-MI and then 13 days of TDM (pTDM). Milk yield responses to the 24h-MI (corrected for effects of stage of lactation, parity, milk yield level and milk yield) were related to physiological traits measured during cTDM (milk flow rate, presence or absence of interleukin-8) and to their changes during the 24h-MI (absolute increase in milk flow rate and relative udder distension). Analysis of associations between milk yield responses, stage of lactation, parity, milk yield level, proteolysis, udder expansion and immune traits found three adaptive cow profile clusters. Cows in cluster 1 had a less compliant udder than cows in cluster 2, and they lost more milk during the 24h-MI than cluster-2 and cluster-3 cows. After resuming twice daily-milking (TDM), cluster-2 cows fully recovered the milk they had lost during the 24h-MI. On the opposite, cluster-3 cows did not recover the milk they lost, likely due to udder inflammation during cTDM, as suggested by elevated concentrations of interleukin-8 in their milk. These results combining new traits with stage of lactation, parity and milk yield level constitute a first step towards predicting individual cow responses to a 24h-MI.

New strategies must be developed to improve poultry performance and health. One of these strategies is the use of supplementations as sodium butyrate (SB) to improve the physiological status and then increasing the growth performance, but the best period of age in which the addition of SB is more effective on birds is not well understood. Therefore, the aim of this study was to investigate the effect of dietary inclusion of SB supplementation through the first, second or whole growth period on some physiological indices and growth performance of growing Japanese quail. In total, 240 unsexed 1-day-old quail chicks were divided into four groups (three replicates per group of 20 chicks in each). The first group was fed basal diet without SB from 1 to 42 days (control, T1), while SB at a rate of 1 g/kg basal diet was mixed with the feed of the 2nd, 3rd and 4th groups of chicks from 1 to 21 days (SB 1 to 21, T2), 1 to 42 days (SB 1 to 42, T3) and 22 to 42 days (SB 22 to 42, T4) of age, respectively. The results stated that addition of SB significantly improved live BW at 21 days, feed conversion ratio (FCR) and BW gain (BWG) during 1 to 21 days in T2 and T3 groups compared to T1 and T4 groups. During the whole period, group T3 had higher BWG and better FCR than the other groups (T1, T2 and T4). At 21 days, no significant differences among all treatments were detected on haematology and serum biochemistry except total protein and cholesterol. At 42 days, SB supplementation significantly improved most serum constituents, haematological parameters, villus height and width of intestine and morphometry of immune organs. The group fed SB throughout the experiment (T3) showed the best results. In conclusion, it is recommended feeding quail on diets containing SB through the whole growth period to show its affirmative impact on the growth and physiological indices.

Light colors may affect poultry behaviors, well-being and performance. However, preferences of layer pullets for light colors are not fully understood. This study was conducted to investigate the pullet preferences for four light-emitting diode colors, including white, red, green and blue, in a lighting preference test system. The system contained four identical compartments each provided with a respective light color. The pullets were able to move freely between the adjacent compartments. A total of three groups of 20 Chinese domestic Jingfen layer pullets (54 to 82 days of age) were used for the test. Pullet behaviors were continuously recorded and summarized for each light color/compartment into daily time spent (DTS), daily percentage of time spent (DPTS), daily times of visit (DTV), duration per visit, daily feed intake (DFI), daily feeding time (DFT), feeding rate (FR), distribution of pullet occupancy and hourly time spent. The results showed that the DTS (h/pullet·per day) were 3.9±0.4 under white, 1.4±0.3 under red, 2.2±0.3 under green and 4.5±0.4 under blue light, respectively. The DTS corresponded to 11.7% to 37.6% DPTS in 12-h lighting periods. The DTV (times/pullet·per day) were 84±5 under white, 48±10 under red, 88±10 under green and 94±8 under blue light. Each visit lasted 1.5 to 3.2 min. The DFI (g/pullet·per day) were 27.6±1.7 under white, 7.1±1.6 under red, 15.1±1.1 under green and 23.1±2.0 under blue light. The DFT was 0.18 to 0.65 h/pullet·per day and the FR was 0.57 to 0.75 g/min. For most of the time during the lighting periods, six to 10 birds stayed under white, and one to five birds stayed under red, green and blue light. Pullets preferred to stay under blue light when the light was on and under white light 4 h before the light off. Overall, pullets preferred blue light the most and red light the least. These findings substantiate the preferences of layer pullets for light colors, providing insights for use in the management of light-emitting diode colors to meet pullet needs.

Learning and mental abilities of farm animals are important for their adaptation to new environments and could serve as an indicator for welfare and performance. This study assessed the learning ability and memory retention of broiler breeders through a T-maze test with a reward v. no reward set-up. Feed supplemented with or without meal worms served as a reward. Two trials were conducted with either parent stock (PS) breeders or pure line A (PL) breeders and with the same dietary treatment namely a control (C) group fed with standard commercial diets and a reduced balanced protein (RP) group fed with RP diets (25% reduction of CP and amino acids). To maintain similar target BW, the RP group received on average 10% more feed. A tonic immobility (TI) test was performed to estimate the fearfulness of PS breeders. Most breeders were capable of completing the T-maze tests, but the C group needed less time compared with the RP group when their own feed was given as a reward. However, when meal worms were provided as an extra incentive, the RP group completed the maze significantly faster than the C group. Compared to the C breeders, the RP breeders remained longer in a TI state, indicating a higher level of fearfulness. Long-term memory retention in the T-maze test was observed in both groups. It is concluded that the RP diet had no influences on the learning ability of the reward v. no reward discrimination test and its memory retention of broiler breeders. The increased amount of time the RP breeders needed to solve the test was probably due to a higher sense of fear. Furthermore, the RP diet enhanced the motivation of breeders to obtain an alternative feed such as meal worms.

The effect of reduced balanced protein (RP) diet in the F0 and F1 generation of broiler breeders on the learning ability and memory retention of the F2 generation was investigated by means of a reward v. no reward discrimination T-maze test. There were two treatments for the F0 generation: control (C) group, reared on standard commercial diets, and reduced balanced protein (RP) group, fed with RP diets (25% reduction in CP and amino acids). The female F0-progeny of each treatment was again separated into the two dietary treatments, resulting in four treatments for the F1 generation: C/C, C/RP, RP/C and RP/RP (breeder feed in F0/F1 generation). The RP diets fed breeders received on average 10% more feed than C diets fed breeders to achieve a similar target BW. The F2 generation was composed of four treatments coming from the female F1-progeny of the four treatments and were all fed with C diet (namely C/C/C, C/RP/C, RP/C/C and RP/RP/C). All four F2 generation groups were able to complete the T-maze learning test with a slight difference in success rate but a significant difference within groups was observed regarding the time needed to complete the test. In general, the RP/RP/C group needed more time for completing the test compared with the other three groups and the shortest time was recorded for the RP/C/C group. At similar ages, breeders with early learning experience spent significantly less time in completing the test compared with unexperienced breeders. Long-term memory retention was observed in all four groups whereas the learning ability in solving the test decreased with age. It took longer for the breeders to complete the test at older ages. In conclusion, under our experimental conditions, the RP dietary treatment in previous generations had no influence on the T-maze learning ability and memory retention of broiler breeders of the third generation, although it might have effects on the working performance in the T-maze learning test of F2 generation breeders.

On-farm hatching systems for broiler chicks are increasingly used in practice. We studied whether or not performance, health and welfare aspects differed between commercial flocks hatched on-farm or in a hatchery (control). In two successive production cycles on seven farms, a total of 16 on-farm hatched flocks were paired to 16 control flocks, housed at the same farm. Paired flocks originated from the same batch of eggs and were subjected to similar on-farm management. On-farm hatched and control flocks only differed with respect to hatching conditions, with on-farm hatched flocks not being exposed to, for example, chick handling, post-hatch feed and water deprivation and transport, in contrast to control flocks that were subjected to standard hatchery procedures, subsequently transported and placed in the poultry house. Day-old chick quality (navel and hock scores), 1st week mortality, total mortality, BW at day (d) 0, d7 and at depopulation, and (total) feed conversion ratio were determined. Prevalence of footpad dermatitis, hock burn, breast discoloration/blisters and cleanliness, litter quality and gait score were determined at d21 of age and around depopulation (d39 on average). Gross pathology and gut morphology were examined at depopulation age in a sample of birds of five flocks per treatment. On-farm hatching resulted in a higher BW at d0 (Δ=5.4 g) and d7 (Δ=11.5 g) (P<0.001), but day-old chick quality as measured by navel (P=0.003) and hock (P=0.01) quality was worse for on-farm hatched compared to control birds. Body weight, 1st week and total mortality, and feed conversion ratio at slaughter age were similar for both on-farm hatched and control flocks. On-farm hatched flocks had less footpad dermatitis (P=0.05), which indicated a better welfare. This was likely related to a tendency for better litter quality in on-farm hatched flocks at 21 days of age in comparison to control flocks (P=0.08). No major differences in gross pathology or in intestinal morphology at depopulation age were found between treatments. In conclusion, on-farm hatching resulted in better 1st week broiler performance and better welfare compared to conventional hatching in a hatchery.

Some routine handling procedures can produce stress in farm animals, and an adequate control of these stressors is important to avoid the negative effects on animal health and production. The measurement of biomarkers in saliva can be a suitable tool for the evaluation and control of stress. In this report, lipase, butyrylcholinesterase (BChE), total esterase (TEA) and adenosine deaminase (ADA) activities in the saliva of sheep were evaluated as biomarkers of stress. For this purpose, they were measured after inducing stress by facing a dog (experiment 1) and shearing (experiment 2), and comparing them to other stress salivary biomarkers such as α-amylase (sAA) and cortisol, as well as heart rate (HR). Each analyte was measured at the basal time, and during and just after the end of the stressful stimulus, and at various times for the first hour after the period of stress induction. Values were compared with those obtained from a control group. Lipase was the only analyte that showed significant changes between the stress and the control group in both experiments. Although TEA and ADA increased after stress, no significant differences were seen compared with the control group. Lipase was correlated highly with sAA and HR, in experiment 1; and correlated moderately with cortisol and HR in experiment 2. Lipase showed the greatest percentage increase after the stressful stimuli and less overlap with the control group in the two experiments. From the results of this study it can be concluded that lipase, TEA, BChE and ADA are enzymes present in the saliva of sheep and that they can be measured by using simple and fast colorimetric methods. Further studies should be undertaken with regard to the possible application of lipase as a biomarker of stress in sheep.

There is community concern about the treatment of farm animals post-farm gate, particularly animal transport and slaughter. Relationships between lamb behavioural and physiological variables on farm, stockperson, dog and lamb behavioural variables pre-slaughter and plasma cortisol, glucose and lactate in lambs post-slaughter were studied in 400 lambs. The lambs were observed in three behavioural tests, novel arena, flight distance to a human and temperament tests, before transport for slaughter. Closed-circuit television video footage was used to record stockperson, dog and lamb behaviour immediately before slaughter. Blood samples for cortisol, glucose and lactate analyses were collected on farm following the three behavioural tests and immediately post-slaughter. The regression models that best predicted plasma cortisol, glucose and lactate concentrations post-slaughter included a mixture of stockperson and dog behavioural variables as well as lamb variables both on-farm and pre-slaughter. These regression models accounted for 33%, 34% and 44% of the variance in plasma cortisol, glucose and lactate concentrations post-slaughter, respectively. Some of the stockperson and dog behaviours pre-slaughter that were predictive of the stress and metabolic variables post-slaughter included the duration of negative stockperson behaviours such as fast locomotion and lifting/pulling lambs, and the duration of dog behaviours such as lunging and barking at the lamb, while some of the predictive lamb behaviour variables included the durations of jumping and fleeing. Some of the physiological and behavioural responses to the behavioural tests on farm were also predictive of the stress and metabolic variables post-slaughter. These relationships support the well-demonstrated effect of handling on fear and stress responses in livestock, and although not direct evidence of causal relationships, highlight the potential benefits of training stockpeople to reduce fear and stress in sheep at abattoirs.