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Currently available conventional breeding methods for broilers often result in impaired biomechanics and skeletal growth for the animals. The addition of environmental enrichment is an alternative which can help alleviate these effects. This study examines the effects of environmental enrichment on biomechanics, morphometry, and bone mass of broilers across various age groups. In total, 112 Cobb 500 chicks (50% male and 50% female) were used in a completely randomized design experiment, with 56 broilers per treatment (T1 and T2), carried out in subdivided plots. Each plot was subjected to a different treatment, as follows: all plots were subjected to the treatments (T1 = environmental enrichment and T2 = no environment enrichment) and the sub-plots held the broilers' age groups (1, 7, 14, 21, 28, 35 and 42 days old). Eight broilers were euthanized on a weekly basis for two production cycles in order to perform morphometric (diameter and length) and biomechanical analysis of the response variables. These measurements were performed on the femur and tibia. Birds were subjected to classical linear fixed effects model and compared through Tukey's mean test. Significant interactions between environmental enrichment and broiler age were noticed, particularly at 42 days, which displayed bone development for all variables under study. Except for the length of the femur of broiler chickens (p = 0.4638). Therefore, simple effects will not be evaluated. Environmental enrichment had a notable impact on tibia length (p = 0.0035), femur weight (p = 0.0014), and tibia weight (p<0.0001) at 42 days, indicating a favorable effect on skeletal growth in broilers. Enrichment resulted in a 1% increase in femur inertia, a 2% rise in tibia inertia, and a 1% enhancement in ultimate bending stress for both bones, displaying improved structural integrity and durability. Beneficial changes in bone morphology and biomechanics were observed at 42 days after enrichment., Competing Interests: The authors have declared that no competing interests exist., (Copyright: This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.)

The objectives of this study were: (i) to verify and compare the coat surface temperature (CST) of regions of interest (ROI) measured through infrared pyrometer (IRP) and thermography (IRT) under two environmental conditions, to evaluate (ii) reliability and (iii) sensitivity of the two infrared equipments to the environmental effect. Twenty hair ewes (Ovis aries), multiparous, non-lactating, non-pregnant, with body weight 59.38 ± 6.23 kg and body score condition ranging from 2.5 to 4.5 were evaluated. All CST, in both infrared methods, were higher (P < 0.001) in the afternoon (2 to 3 p.m.), with the exception of eyes surface temperature (TSEY) from IRT, which was higher (P < 0.001) in the morning (8 to 9 a.m.). Regarding the infrared methods at different times (twice a day, morning and afternoon), of the day, CST values for all ROIs were significantly higher (P < 0.001) in thermography, regardless of the time shift, except for ear pinna surface temperature (TSE) and rectum surface temperature (TSR), which showed no significant difference (P > 0.05) between the infrared methods during the morning shift. The thermal environment significantly influences (P < 0.001) the surface temperature of various anatomical regions in both infrared methods. The correlation coefficients between IRT and IRP were moderate. The IRT is more sensitive to the thermal environment, as it presented higher canonical coefficients in the environmental variables. Among surface temperatures, eye surface temperature is the most influenced by variables in the thermal environment, especially THI. All three methods (digital thermometer-DT, IRT and IRP) showed >80 % of the data variation in the first two components. Using the DT, we observed an association between vaginal temperature (VT) and RT with air temperature (AT) and temperature humidity index (THI), which was similar to the infrared thermography pattern, in which all ROIs were highly correlated with AT and THI. The opposite was observed in the pyrometer, in which an association between eye temperature and RH and lower factor loadings of the other ROIs with AT and THI in the first component was observed. In conclusion, while IRP and IRT showed similar performance in the morning, IRT proved to be more accurate in the afternoon, demonstrating a higher success rate in classifying the group of origin. Therefore, it is concluded that IRT is more reliable than IRP in detecting surface temperature changes under high temperatures., Competing Interests: Declaration of competing interest The authors declare that they have no conflicts of interest., (Copyright © 2024. Published by Elsevier Ltd.)

This study aimed to evaluate forage production and ingestive behavior of Morada Nova sheep in an intensive system with capim-tamani grass in both monoculture and silvopastoral irrigated systems in the Semi-arid region. Eighteen adult sheep, approximately 3 years old, with an average body weight of 26.8 ± 4.3 kg, were allocated to treatments with capim-tamani grass cultivated in monoculture and in silvopastoral systems with Caatinga trees. The experiment followed a completely randomized complete block design with two plots and three replications. Forage production, consumption, and behavioral activities were the assessed variables. The animals remained in the pasture daily between 6 am and 6 pm. No effects of the monoculture and silvopastoral systems were observed on the structural and productive characteristics of the capim-tamani grass pasture. There were also no observed effects on body condition score, consumption, and disappearance rate of dry matter (DM) and other nutrients in both systems. However, there was an interaction between the time animals spent under shade in monoculture and silvopastoral systems. In general, the animals spent more time under shade where there were trees, except during the period between 2 pm and 4 pm, when the times were similar. On average, the animals spent approximately 15.6% (equivalent to 1.87 h) of their total time in the artificial shade available in the monoculture system, whereas in the silvopastoral system, they remained under natural shade for approximately 40% (five and a half hours) of their time spent in the pasture during the day. The grazing frequency in both systems was approximately 70% (8.4 h) in relation to the total time spent in the pasture. The capim-tamani grass pasture managed intensively with sheep in the silvopastoral system showed similar forage production and consumption compared to the monoculture system. There was a positive influence of trees on the duration of solar radiation exposure to the animals throughout the day. The results support the need to provide shade for sheep, as well as to promote these sustainable systems in semi-arid regions., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

The present study describes the expression of genes in the Longissimus dorsi muscle related to meat quality of hair lambs finished in an Integration Crop-Livestock system. Twenty-eight non-castrated lambs of two breeds, Somalis Brasileira and Santa Inês, at 120 ± 15 days of age, with an average initial live weight of 18 ± 3.1 kg, were kept in a pasture-based finishing system with supplementation. Upon reaching 28 kg body weight, animals were sent for slaughter. Samples of the Longissimus dorsi and Biceps femoris muscle were harvested for analyses of gene expression and physicochemical properties. Significant differences were detected between the breeds for tissue and chemical composition, whereas the physical aspects did not differ. We observed the expression of six genes related to lipid synthesis (acetyl-CoA carboxylase [ACACA], fatty acid synthase [FAS], stearoyl-CoA desaturase [SCD], lipoprotein lipase [LPL], cell death-inducing DFFA-like effector A [CIDEA], and thyroid hormone responsive [THRSP]) and six genes related to molecular synthesis (myostatin [MSTN], growth differentiation factor 8 [GDF8], insulin-like growth factor 1 [IGF1], insulin-like growth factor 2 [IGF2], delta-like 1 homolog [DLK1], and growth hormone receptor [GHr]) in both breeds. The Santa Inês breed and the Somalis Brasileira showed similar expression patterns of genes related to lipogenesis and myogenesis of the Longissimus dorsi muscle, with the exception of the THRSP gene, in which the Somalis Brasileira have more receptors for the action of thyroid hormones, which resulted in greater thickness of fat in the carcass (subcutaneous fat) and higher lipid content in the chemical composition of the meat., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

The Morada Nova sheep breed is essential for the economy of the semi-arid region of Northeast Brazil, standing out for its adaptability, resistance to parasites and reproductive ability. However, the white variant is endangered, highlighting the importance of studies on its productivity to support conservation efforts. This study focuses on the growth curve of the Morada Nova sheep breed, using nonlinear models and analyzing flock profiles. Total of 764 observations of 165 animals from four farms in Ceará and Rio Grande do Norte, Brazil, were analyzed. Canonical discriminant analysis (CDA) was used for the exploratory analysis and four nonlinear models were used to study the growth curve. Weight from birth to 270 days of age, absolute growth rate (AGR), and the impact of sex on growth curves were assessed. Sex and farm are significant discriminating variables (P < 0.05) for the studied effects (weight and age). Weight was the primary phenotypic biomarker that discriminated between the two indicators, while age was a discriminating indicator only for the core effect. The Gompertz model was the most efficient, presenting the lowest residuals and greatest convergence. The study reveals new information about the growth of Morada Nova sheep, the white variety, including weight differences between the sexes at all analyzed ages and an inflection point before 90 days of age. These discoveries contribute to the understanding of the breed's growth and help in the formulation of conservation strategies., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

This study aimed to evaluate the thermal performance and meat quality in broilers reared in positive pressure tunnel ventilation (PP) and negative pressure tunnel ventilation (NP) in production houses. 320 Cobb broilers (40 broilers per house) were used. Pectoralis major muscles from 40 broilers (10 broilers per house) were randomly selected and analysed for L* (lightness), a* (redness), b* (yellowness), pH, drip loss (DL), cooking loss (CL) and shear force (SF). Air temperature and humidity of the transportation and slaughterhouse waiting room were recorded in the last week of rearing. Subsequently, the enthalpy comfort index (ECI) was calculated. Air temperature and ECI were higher ( p < 0.05) in positive pressure sheds, whereas relative humidity was higher ( p < 0.001) in negative pressure sheds. There was no statistically significant difference between the enthalpy comfort index during transport and lairage ( p > 0.005). Meat quality defects (high L*, DL, CL, SF) were found in PP and NP. It was observed that b* was higher in PP, although pH and CL were higher in NP. Differences in pH, b* and CL indicate that broilers from PP had a higher level of heat stress. In conclusion, differences in pH, b*value and cooking loss in breast broilers indicate that birds in PP had a higher level of heat stress. Additional studies investigating pre-slaughter handling methods to minimise injuries and heat stress are recommended in order to improve animal welfare and meat quality.

Coat color is a factor affecting heat tolerance in tropical ruminant and a particular coat color can determine which is more resilient to environmental changes. The aim of this study was to measure the level of adaptation of Morada Nova sheep with different coat color by using an Adaptability Index (AI). Adult ewes were used, including two different coat colors of Morada Nova sheep (red and white) with mean of body weight of 28.02 ± 5.70 kg and 31.47 ± 3.41 kg, respectively. Physiology parameters, hematology, electrolytes, acid-base status, mineral, renal functions, metabolites, enzymes, and proteins were measured. AI was designed using a multivariate approach (principal component analysis) to "weigh" the influence of each variable in the animal responses. The variables more important for adaptive aspects of Red Morada Nova were: haematology, electrolytes and acid-base status. The hemoglobin (HG), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), sodium (Na + ), oxygen pressure (PO 2 ), glucose (GLU) and albumin (ALB) were significantly higher in Red Morada Nova sheep and hydrogen carbonate (HCO 3 ), base excess (BE), total carbon dioxide concentration (TCO 2 ) and URE were significantly higher in the white phenotype. The variables more important for adaptive aspects of White Morada Nova sheep were: (K + ), total protein (TP), PO 2 , HG, cholesterol (CHO), rectal temperature (RT) and glucose (GLU). Both phenotypes showed a high adaptation level, however, a higher value was generated for the Red Morada Nova sheep (81.97). This study concludes that both phenotypes of the Morada Nova sheep breed are well adapted to the climatic condition of the Brazilian tropical region using different adaptive mechanisms., (© 2024. The Author(s) under exclusive licence to International Society of Biometeorology.)

Different resources, such as environmental enrichment, are being evaluated in order to minimize animal stress and promote better conditions during the life cycle of animals, as consumers are increasingly concerned about animal welfare issues. Lairage represents an important stage in the swine production chain and is directly related to animal welfare. The aim of this study was to evaluate the effect of lairage time in the slaughterhouse and environmental enrichment on the level of skin lesions and behavioral responses in pigs. A total of 648 finishing pigs of both sexes were assessed before and after lairage at the slaughterhouse with a five-point scale (0 = none, to 4 = ≥16 superficial lesions or >10 deep lesions). After lairage (after slaughter), lesions were also classified according to their source (mounting, fighting, and handling). Pigs were distributed into two treatments groups during lairage: with environmental enrichment (EE) on the pen, with hanging metal chains, and with no enrichment (NE). Behavior was monitored during the first four hours of lairage. Proportional odds, mixed linear model for longitudinal data, and non-parametric Wilcoxon signed rank tests were used to analyze the relation between treatments, skin lesions, and behavior. The simple metal chains did not affect skin lesion score or pigs' behavior ( p > 0.05), whereas lairage duration influenced standing (SA), sitting (S), lying (L), idleness (I), and drinking water (D) ( p < 0.001). The main source of skin lesions was handling, which did not differ between treatments (EE and NE) ( p > 0.05). It was observed that the severity of the lesions (highest scores of 3, 4, and 5) increased in the different anatomical regions of the pigs when compared before and after slaughter, with the exception of the frontal area, which was the same ( p = 0.7547). Lairage time has a proportional relation with skin lesions, and hanging chains at the slaughterhouse pens was not enough to reduce the number of lesions and to change pig behavior.

The proliferation of rearing systems providing opportunities for birds to engage in natural behaviors can trigger behavioral repertoires that when not manageable compromise animal welfare and the economic viability of the flock. Smothering in laying hens has long been perceived as "natural" or the result of hysteria among birds in the flock. However, the current literature has recognized smothering as an abnormal outcome with the potential to result in significant losses in cage-free poultry systems. Recent studies have specifically aimed to categorize the organization of smothering behavior and highlight its potential causes and consequences. In this study, literature review and bibliographic mapping, drawing on published articles and engagement with poultry farmers through extension and rural technical assistance, were employed. The findings indicate that smothering is a behavior triggered by factors related to the environment in which the laying hens are kept. This study concludes that there is a critical need for more rigorous and detailed research to elucidate the nuances of avian behavioral physiology and assess the impact of production systems on animal welfare and the economic impacts on the flock. This research contributes to a deeper understanding of bird behavior in high-production environments and provides practical insights for the poultry industry.

Biscuit bran (BB) is a co-product with worldwide distribution, with Brazil as the second largest cookie producer in the world with 1,157,051 tons. We evaluate the impact of completely replacing corn with BB on the characteristics and morphometry of carcass of purebred and crossbred Morada Nova lambs using machine learning techniques as an auxiliary method. Twenty male lambs from two genetic groups (GG) were used: purebred red-coated Morada Nova (MNR) and crossbred MNR × white-coated Morada Nova (MNF1). Supervised and unsupervised machine learning techniques were used. No interaction (P > 0.05) was observed between diets (D) and genetic groups (GG) and no simple isolated effect was observed for carcass characteristics, qualitative-quantitative typification of the Longissimus dorsi muscle, weight of non-carcass components, weight and yield of commercial cuts and carcass morphometric measurements. The formation of two horizontal clusters was verified: (i) crossed lambs with corn and BB and (ii) purebred lambs fed corn and BB. Vertically, three clusters were formed based on carcass and meat characteristics of native lambs: (i) thermal insulation, body capacity, true yield, and commercial cuts; (ii) choice, performance, physical carcass traits, and palatability; and (iii) yield cuts and non-carcass components. The heatmap also allowed us to observe that pure MN lambs had a greater body capacity when fed BB, while those fed corn showed superiority in commercial cuts, true yields, and non-carcass components. Crossbred lambs, regardless of diet, showed a greater association of physical characteristics of the carcass, performance, palatability, and less noble cuts. Crossbred lambs, regardless of diet, showed a greater association of physical characteristics of the carcass, performance, palatability, and less noble cuts. BB can be considered an alternative energy source in total replacement of corn. Integrating of machine learning techniques is a useful statistical tool for studies with large numbers of variables, especially when it comes to analyzing complex data with multiple effects in the search for data patterns and insights in decision-making on the farm., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

In poultry farming, robots are considered by birds as intruder elements to their environment, because animals escape due to their movement. Their escape is measured using the escape distance (ED) technique. This study analyzes the behavior of animals in relation to their ED through the use of a robot with two speeds: 12 rpm and 26 rpm. The objective is to understand whether the speeds cause variations in ED and their implications for animal stress. A broiler breeding cycle was analyzed (six weeks) through the introduction of the robot weekly. ED analyses were carried out on static images generated from footage of the robot running. The results indicate higher escape distance rates ( p < 0.05) peaking midway through the production cycle, notably in the third week. Conversely, the final weeks saw the lowest ED, with the most significant reduction occurring in the last week. This pattern indicates a gradual escalation of ED up to the fourth week, followed by a subsequent decline. Despite RPM12 having shown low ED results, it did not show enough ED to move the animals away from their path of travel, causing bumps and collisions. RPM26 showed higher ED in all breeding phases, but showed ED with no bumps and collisions.

This study aimed to evaluate and compare the physiological performance of different genetic groups of sheep, by physiological variables and serum hormone levels, in a hot weather environment. Thirty sheep from five genetic groups were used: Santa Inês (SI), ½ Dorper + ½ Santa Inês (DO), ½ Ilê de France + ½ Santa Inês (IF), ½ Suffolk + ½ Santa Inês (SK), and ½ Texel + ½ Santa Inês (TX). The readings and records of physiological parameters (respiratory rate (RR), rectal temperature (RT), auricular cavity temperature (ACT), and surface temperature (ST)) were carried out at 7:00 am, 1:00 pm, and 7:00 pm, in 12 non-consecutive days. The collections of blood samples for hormone analysis (triiodothyronine (T 3 ), thyroxine (T 4 ), and cortisol (CORT)) is in four consecutive days. The environmental conditions of the experimental period caused a thermal discomfort in the sheep, but not a state of thermal stress. The thermolysis mechanisms, sensitive (ST and ACT) and latent (RR) processes, were enough to maintain their homeostasis (RT). The results showed that crossbred breeds presented a higher metabolism and were more efficient at dissipating heat through thermolysis than the SI breed. The crossbred breeds were efficient at dissipating heat through the elevation of body surface temperature and respiratory rate, mainly SK and TX, i.e., crossbred breeds, despite the wool cover, used thermoregulatory mechanisms that promoted lower variation of RT. The analysis of variance showed significant effects (P < 0.05) to the time factor in the responses of T 4 and T 3 , and to the breed factor in the responses of CORT, T 4 , and T 3 . We did not observe interaction between the factors to any of the hormonal variables. Therefore, we can state that the effect of time was independent of breed and vice versa. Thyroid hormones presented lower blood concentration in the mornings (4.03 ± 0.82, T 4 ; 65.08 ± 10.6, T 3 ), increasing their concentration in the afternoon (4.60 ± 1.03, T 4 ; 70.16 ± 14.17, T 3 ). The thyroid hormones presented a normal circadian rhythm, with the exception of SK. Air temperature (AT) showed greater correlation with physiological variables than enthalpy (H) did, in the experimental conditions. However, H showed correlation with T 4 and T 3 . The adaptive profile of the genetic groups under study are different, but the IF genetic group showed better performance under environmental conditions., (© 2023. The Author(s) under exclusive licence to International Society of Biometeorology.)

Animal welfare and productive performance are compromised when animals are housed in environments which place them outside their thermal comfort zone. However, the identification of thermal stress, when based on air properties, suggests the use of outdated and generic indices. The objective of this work was to develop and validate a methodology for classifying and diagnosing heat stress in production animals based on psychrometric air relations. The model was created for broilers, pigs, dairy cattle, and laying birds, categorized into a total of 21 breeding phases. For each phase, a bibliographic search was carried out for the psychrometric parameters of the air-dry bulb temperature (AT) and relative humidity (RH)-that satisfied the animals' critical and ideal thermoneutral zones. Adding the local atmospheric pressure (AP), the parameters were used to calculate the enthalpy (h), resulting in five comfort ranges. Based on this, a decision tree was elaborated, consisting of three attributes (AT, RH, and h) and seven diagnostic classes, based on the psychrometric principles of air. The proposed methodology was used in a case study, with a database extracted from an individual shelter for calves. For the evaluation of the decision tree, two induction algorithms, ID3 and c4.5, were compared, both of which presented high accuracy and proposed simpler tree models than the one theoretically developed for the methodology. In conclusion, the methodology represents a great potential to characterize the thermal comfort of the animals, diagnose the causes of stress, and recommend possible corrective actions. The study revealed that decision trees can be adapted and simplified for each creation phase., (© 2023. The Author(s) under exclusive licence to International Society of Biometeorology.)

The objective of the study was to characterize the adaptive profile of Ibero-American sheep of the Canaria breed, evaluating the possible changes in thermoregulatory responses and coat characteristics to which the animals are exposed in the different seasons of the year. Data collected over a period of 12 months were analyzed, with information being observed in the interval of 15 days of each month, in 23 adult ewes kept in an intensive breeding system. The rectal temperature (RT) of Canaria ewes was higher (P < 0.001) in the summer and spring seasons. In contrast, the respiratory rate (RR) of the animals was higher in autumn. The surface temperature (ST) of the herd was lower during the spring. It was observed that the hair length (HL) and the hair density (NH) did not vary during the seasons. However, the hair diameter (HD) and the coat thickness (CT) varied, being in the spring, the season in which the animals had the highest HD and autumn, the season in which they had the lowest. The performance was similar throughout the seasons (P > 0.05). The morphological variables of the coat presented 63.8% of original cases grouped, which may characterize the morphological responses of the coat of these animals as an important trait of the adaptive profile of the breed, whereas the opposite occurred for thermoregulatory responses. The variables most used by the herd and that were most important were autumn (CT, NH, HD, HR, RT, and HL), summer (ST and RR), spring (RR, ST, and RT), and winter (RT, HD, HR, and RR). Sheep of the Canaria breed have an adaptive profile that dynamically uses thermoregulatory and morphological responses, molding themselves according to climate changes resulting from seasonal periods on the Island of Tenerife, Spain. The Canaria sheep stood out for the modification of the morphological characteristics of the coat, especially during autumn and spring, and can be considered an excellent genetic resource with excellent adaptive characteristics for arid environments such as those found in the Canary Islands., (© 2023. The Author(s) under exclusive licence to International Society of Biometeorology.)

The aim of this study was to evaluate the effect of the polymorphic FecG E allele on reproductive traits in Santa Inês and Morada Nova ewes. The traits evaluated were as follows: total progeny weights at birth (PWB) and weaning (PWW) and progeny survival rates at birth (PSRB) and weaning (PSRW). A total of 389 animals, belonging to two Santa Inês herds and one Morada Nova herd, were genotyped. There was a difference between the averages for all the traits studied regarding type of parturition, herd/breed, genotype/herd, and genotype/type of parturition. For each additional progeny, if the female was FecG E/E , the PWB decreased by 1.02 kg and the PWW by 3.16 kg, also with a 0.04% reduction in PSRB and no change in PSRW. If the female was FecG E/+ , the reduction in PWB was 0.24 kg, with an increase in PSRW by 0.11%, but no change in PWW and PSRB. In general, these results demonstrate that FecG +/+ females have a better ability to increase their number of progenies without reducing PWB and PWW (also similar to FecG E/+ ). Thus, it is suggested that further studies on the association between the traits of interest and candidate genes in sheep should be carried out so that the regions which have the greatest effect on the expression of these traits are actually identified. It was not possible to verify the effect of the FecG E allele on the PWB, PWW, PSRB, and PSRW in these Morada Nova and Santa Inês herds., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

The resistance of pigs' bone structure was evaluated for the first time, reared with and without environmental enrichment (EE) in the finishing phase using techniques in bone biomechanics; 432 swine from the Hampshire breed, being males and females, with initial body weight between 22 and 27 kg and final body weight between 110 and 125 kg were evaluated for 112 days. The experimental design was in randomized blocks, with 6 treatments, distributed in a 2 × 3 factorial scheme (sex × conditions in creation), with 12 repetitions/treatment, totaling 72 pens. The treatments were as follows: branched chain for males (T1), sisal branched string for males (T2), males without EE (T3), branched chain for females (T4), sisal branched string for females (T5), and females without EE (T6). At the end of the experimental period, all animals were slaughtered in an industrial slaughterhouse, having their femur bones collected for bone biomechanics analysis. There was no effect (P > 0.05) of the interaction (enrichment × sex) and individual factors for bone weight. There was a tendency (P = 0.08) of the interaction for flexion force, being higher in males enriched with branched ropes and chains. For breaking stress, there was an interaction effect (P = 0.04), being the females without EE the ones showing the lowest breaking stress, favoring bone fragility. The use of branched ropes and chains strengthens the bone structure in swine in the termination phase (110-125 kg BW - 183-190 days in age), being an important strategy used to meet the animal welfare requirements., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

For all the benefits of a compost barn system to be achieved, the management, especially with the bedding, must be done correctly. One should consider the requirements regarding the revolving of the material, use of good quality organic matter, suitable ventilation, and an ideal animal stocking rate, so that the composting occurs efficiently. Given this, this work aimed to evaluate the spatial variability of thermal characteristics of rice straw bedding, using values of temperature (surface and internal) and humidity. The temperature and moisture values of the litter were recorded at intervals during the morning shift, from 6:00 am to 7:00 am and from 8:00 am to 9:00 am, and during the afternoon shift, from 3:00 pm to 4:00 pm and from 5:00 pm to 6:00 pm, considering the management of the turn-over, that is, before and after the movement of the litter. Litter variables were collected at points distributed on a 39-point grid. There were no differences between litter surface temperatures before and after turning over in the morning shift, but in the afternoon shift, the surface temperature was lower (P < 0.05) before, when compared to after turning. The internal temperature and litter moisture were higher (P < 0.05) before revolving in both shifts. Spatial dependence was verified (IDE) for the variables studied. Based on the geostatistical analysis, it is concluded that the IDE was rated as strong for surface and internal temperatures, which demonstrates heterogeneity among the points evaluated and a large spatial variability regarding bed temperatures. In the case of litter moisture, the greatest variability occurred in the morning period. The litter surface temperature values did not exceed the ambient air temperature values., (© 2023. The Author(s) under exclusive licence to International Society of Biometeorology.)

The aim of this study was to evaluate the effect of adding selenium-enriched yeast (SE) in the diet of dairy goats during 60 days of lactation and its effect on productive, thermoregulatory, and hormonal responses of animals managed in a semi-arid region. Sixteen Saanen × Toggenburg crossbred goats were used in a completely randomized design. Goats were weighed, and their milk yield was monitored weekly. Before the animals entered the treatments and at every 20-day milk producing, blood samples were collected to determine the SE levels. At 20, 40, and days of the lactation cycle, individual milk samples were collected to determine composition, casein, urea nitrogen, and selenium content. Measurements of respiratory rate (RR), rectal temperature (RT), coat surface temperature (CST), and epidermal temperature (ET) were performed weekly during the experimental period in two shifts, one in the morning (9 am) and the other in the afternoon (3 pm). No difference (P > 0.05) was detected for body weight, milk yield, composition, selenium concentration, and urea nitrogen. Lower RR and ET (P < 0.05) were observed for animals that received SE supplementation. Thyroid hormone concentrations were similar between treatments (P > 0.05). The positive results of the SE supplementation were concentrated in thermoregulatory responses, and there was no effect on productive, hormonal responses, and plasmatic concentration of selenium in the milk. The SE supplementation for dairy goats managed in a Brazilian semi-arid region was able to promote reduction of RR and coat temperatures., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

A commercial low-profile cross-ventilated system (LPCV) free-stall barn with evaporative cooling pads on the air intake side was used to assess the potential of cross-ventilation with evaporative cooling to alleviate heat stress in lactating dairy cows. A total of 5712 records (238 days × 24 h) of air temperature (AT) and relative humidity (RH) values were collected. In order to state the effectiveness of the ventilation system and potential heat stress, the temperature humidity index (THI) and enthalpy (h) were calculated outside and inside the LPCV barn. The cooling capacity of the LPCV system is greater in conditions of low humidity, and the difference between the values of the internal and external temperature reached -12 °C. The LPCV reduced exposure to heat stress, increasing the time cows spent in thermoneutral conditions. This system could reduce the occurrence of temperature above 25 °C from 33 to 5% and 11% in sections A (represents the inlet side of the barn) and D (represents the outlet side of the barn), respectively. On the other hand, the LPCV kept a high and constant rate of RH throughout the day. The average inside and outside AT were significantly different, but differences in temperature were observed across the width of the barn. Analyzing the barn by the indexes, the THI showed that the barn promoted cows more time confined under non-stressful thermal conditions (between 83.8 and 90% vs 68.7%) and stress period much lower compared to the external environment (between 10 and 16.2% vs. 31.3%). The enthalpy index showed that there was not much difference between the internal and external environments. The LPCV system is another installation alternative for raising dairy cow in a hot and humid climate., (© 2023. The Author(s) under exclusive licence to International Society of Biometeorology.)

The objective of this study was to evaluate the effect of standardized ileal digestible (SID) tryptophan (Trp) and lysine (Lys) levels on eating and sleeping behavior and the respective feed intake of barrows. Sixty-four pigs, averaging 15.00 ± 1.63 kg of initial body weight, were used and distributed in a randomized blocks design, in a 4 × 4 factorial scheme, consisting of four levels of SID Trp (0.155, 0.185, 0.215, 0.245%) and four levels of SID Lys (0.972, 1.112, 1.252, and 1.392%). Behavior evaluation was performed by an instantaneous sampling using 10-min intervals during 24 h, at each 7 days (days 7, 14, and 21), and each day was divided into four times of 6 h each one (08:30-14:20, 14:30-20:20, 20:30-02:20, and 02:30-08:20 h), during all the experimental period, yielding a total of 3 × 24 h behavior recordings (72 h) × 6 10-min intervals, totalizing 432 observations per animal. Data were analyzed by classifying behavior into eating or sleeping. All these behaviors were measured in order to obtain the estimated frequency of the eating and sleeping behaviors. Changes were observed (P<0.05) for all the behavioral parameters during the starting phase. SID Trp and SID Lys showed an interactive positive effect on the estimated frequency of eating behavior, and mainly SID Trp increased the estimated frequency of the sleeping behavior of starting pigs in the nocturnal time. Pig diets with increasing levels of SID Trp and SID Lys until 0.245 and 1.392%, respectively, increased the average daily feed intake, and the interaction of the amino acids increased the estimated frequency of eating behavior during all the starting phase, and mainly the increasing levels of SID Trp increased the estimated frequency of sleeping behavior of pigs from the middle to the end of the starting phase, from 2:30 to 8:20 h., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

Environmental enrichment consists of a way to provide better living conditions for animals, but its influence on physical integrity, thermoregulatory responses, and quality of pork meat is not known. The objective of this study was to evaluate the thermoregulatory responses, lesion score, lameness, carcass traits, and meat quality of pigs with and without access to environmental enrichment (EE) in the finishing phase. A total of 432 pigs of the Hampshire lineage, males and females, with average initial and final weights between 22-27 kg and 110-125 kg respectively were evaluated. The experimental design used was in randomized blocks, with 6 treatments, distributed in a 2×3 factorial scheme (sex × environmental enrichment), with 12 repetitions per treatment, totaling 72 stalls. The treatments were branched chain for males (T1), branched sisal rope for males (T2), males without EE (T3), branched chain for females (T4), branched sisal rope for females (T5), and females without EE (T6). Weekly, two assessments of physiological data were performed, in loco, in the morning and afternoon. Lesions on the tail, ear, body, and lameness were evaluated on the 1st, 16th, 37th, 51st, 79th, 93rd, and 112th days. On the 112th day, 72 animals were slaughtered for carcass traits and meat quality analyses. Statistical analysis was performed using generalized and mixed linear models. There was no effect (p>0.05) of the interaction of the studied factors (environmental enrichment × sex × period) on the head, back, leg, and average temperature. However, there was an effect of the period factor (p<0.01), with higher temperatures in the afternoon compared to the morning. For tail injury, there was no association between injury degree and gender (p=0.56) and between injury degree and enrichment (p=0.99), and there was no interaction effect (p=0.15). For ear injury, there was no association between the degree of ear injury and gender (p=0.72), as well as for the degree of ear injury and enrichment (p=0.99) and interaction (p=0.47). There was a higher occurrence of categories 2, 3, and 4 for lesions on the body in males (p=0.0257), regardless of the EE. Water retention, carcass yield, cut yield, marbling pattern, pH, and color showed no effect for sex, enrichment, and interaction between the two factors (p>0.05). The use of environmental enrichment with sisal ropes and branched chains does not change the thermophysical responses, carcass traits, and meat quality of finishing pig., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

This study's objective was to evaluate the thermoregulation aspects of native goats through broken-line regression to understand the triggering of physiological responses in the homeothermy process. Data were collected from ten healthy dams of the Canindé breed once a week at hourly intervals (24 h) for eight consecutive weeks. Air temperature (AT; °C), relative humidity (RH; %) were measured and temperature-humidity index (THI) calculated. The thermoregulation parameters evaluated were: respiratory rate (RR; breaths.min -1 ), rectal temperature (RT; °C) and sweating rate (SR; g.m -2 .h -1 ). All variables were subjected to analysis of variance with repeated measures over time. The hour was considered a fixed effect (00:00 h, 01:00 h, …, 23:00 h), and the animal was a random effect. Multiple regression analyses were also examined using General Linear Models and Variance Inflation Factors were calculated. Broken line non-linear regressions for RR, RT and SR were examined using independent variables. The highest average for AT and RH were 35.9 °C (13:00 h) and 92.4% (04:00 h), respectively. The lowest average of TA and RH were 22.1 °C (05:00 h) and 28.0% (12:00 h), respectively. The highest average THI was 102.1 (13:00 h), and the lowest 78.0 (05:00 h). The environmental thresholds at which RR, RT and SR began to increase for AT were between 17-21 °C and RH were > 17% (RR), ≥ 21 (RT) and > 23% (SR). For THI the limits were 108.4 for RR, 78.0 for RT and 100.1 for SR. Using THI, the thermoregulatory parameters are activated in the following order: SR, RR and RT. Estimates can serve as a basis to implement heat stress mitigation and improve animal welfare strategies for native goats., (© 2023. The Author(s) under exclusive licence to International Society of Biometeorology.)

The compost barn is presented as a system which is capable of providing a suitable environment for dairy cows, but this must be assessed for different climatic regions. Few studies have been carried out evaluating the physics of the thermal environment of this system under tropical conditions. In this study, we evaluated thermoregulatory, behavioral, and productive responses and physical integrity in primiparous and multiparous cows housed in a compost barn system under tropical conditions. From a total of 121 clinically healthy dairy cows aged 3 to 6 years, 30 Girolando cows (7/8) were randomly selected, divided into two groups, according to calving order (primiparous and multiparous), body weight, lactation curve and milk production for the evaluations. Thus, group 1 (primiparous) with an average weight of 524 kg and production of 30 kg was characterized, and group 2 (multiparous) with an average weight and production of 635 kg and 36 kg, respectively. The enthalpy was higher (P < 0.05) in the internal environment of the shed at the three evaluated times (3:30 a.m., 11:30 a.m., and 6:30 p.m.), but the humidity did not vary (P > 0.05) between the internal and external environments at the evaluated times. Respiratory rate was higher (P < 0.0001) in multiparous cows at 11:30 a.m., but was similar at 3:30 a.m. and 6:30 p.m. when compared with primiparous cows. The coat surface temperature was higher (P < 0.001) at 3:30 a.m., but similar at the other two times. For the variables lameness and dirtiness, the vast majority of animals presented scores considered adequate (1 and 2), indicating that it was able to provide an ideal physical environment. Regarding animal behavior, panting (O) and lying idle (OD) were higher (P < 0.05) in multiparous cows. Multiparous cows have higher (P < 0.0001) milk production. Milk production has a negative correlation with enthalpy. The CB system was not able to provide a suitable thermal environment for the animals. Multiparous cows present higher heat stress with change in behavioral responses, especially at midday, but with higher milk production when compared to primiparous cows in compost barn under tropical conditions., (© 2023. The Author(s) under exclusive licence to International Society of Biometeorology.)

This study aimed to evaluate the thermoregulatory capacity and performance of Saanen goat kids from birth to weaning in a hot climate. Twelve newborn males and female goat kids with an initial body weight of 4.17 ± 0.81 kg were used. Physiological responses, climatic variables, and biometric traits data were collected. Univariate and multivariate analysis techniques were used. Heart rate (H R ) was high up to the 6th week of life, with a reduction from the 7th week on (P < 0.001). Rectal temperature (R T ) was lower in the first 2 weeks (P < 0.001), with an increase and stabilization occurring in the 7th and 8th weeks. Coat surface temperature (S T ) was more activated from the 5th week onwards (P < 0.001). Body weight (B W ) and withers height (W H ) were higher in later weeks of the calving phase with a linear effect (P < 0.001). The first principal component demonstrated the relationship of sensible heat dissipation × body area of the goat kids; the second component shows the relationship of meteorological data with R T , having a positive relationship between R T with R H and negative with A T , and the third component points to the association of R R and H R . Of the animals, 81.3% were correctly classified in their group of origin in discriminant canonical analysis, with emphasis on the classification of the kids in the 1st-2nd and 3rd-4th weeks (classification percentage Ʃ = 95.8%). It is concluded that (i) newborn kids activate latent mechanisms to maintain their homoeothermic during the first 2 weeks of life, and as they grow, they use sensitive heat loss processes, especially from the 5th week of life onwards and (ii) male and female goats do not show sexual dimorphism effect on body performance and body morphometric measurements up to 60 days of life., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

Productive and behavioral responses of finishing pigs with and without access to environmental enrichment (EE) were evaluated. A total of 432 pigs, male and female, Hampshire line, initial and final weight of 22-27 kg and 110-125 kg, respectively, were studied for 112 days. The study design was in random blocks, with 6 treatments, distributed in a factorial scheme 2 × 3 (sex × treatment) and 12 repetitions/treatment, totalling 72 pens. The animals were weighed and distributed in 3 blocks-light (20.3 to 24.8 kg), medium weight (24.8 to 27.7 kg), and heavy (27.7 to 33.8 kg). The treatments were as follows: branched chains for males (T 1 ); branched sisal ropes for males (T 2 ), males without EE (T 3 ); branched chains for females (T 4 ); branched sisal ropes for females (T 5 ) and females without EA (T 6 ). There was no effect (P > 0.05) of interaction (enrichment × sex) and sex on performance. Daily consumption and daily weight gain were lower (P < 0.05) in the chain group compared to the sisal rope and control groups. Feed conversion was similar (P > 0.05) between treatments under study. There was no interaction between gender and enrichment for behavioral responses (P = 0.8986). However, there was an environmental enrichment (P = 0.0017; P < 0.001) and gender (P = 0.0251; P < 0.001) effect in relation to the animals' behavior in the morning and in the afternoon, respectively. Calmer animals, regardless of sex, were observed for groups without enrichment (control) and morning and afternoon periods. The animals interacted with the types of enrichment under study, given the higher probabilities of interaction with the object for males and females in the morning and afternoon shifts. It was observed, regardless of the shifts, that the control treatment for males and females was different when compared to the other enrichments for males and females. In general, the pigs' behaviors were expressed more in the afternoon when compared to the morning. It was observed that the animal interaction and aggression (afternoon shift) behaviors are more related to the control group, while object interaction is more related to the enriched treatments. The use of sisal ropes and branched chains guarantees the performance and behavior of pigs in the finishing phase, but we recommend the use of branched chains, as this enrichment increased the profitability of the farmer by reducing feed consumption, maintaining feed conversion and animal welfare, besides being a more durable material than sisal rope., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

Genetic parameters were estimated for egg production, egg quality, and eggshell colors in eight lineages of Brazilian laying hens. Age at first egg (AFE), total egg production up to the 45th week (PROD), egg weight (EW), albumen height (AH), yolk color (YC), the Haugh units (HU), eggshell strength (ESS), eggshell thickness (EST), yolk weight (YW), eggshell weight (ESW), and eggshell color (L*, a*, and b*) were measured in 2030 eggs obtained from 645 laying hens. Variance components were estimated from a mixed animal model, which included the fixed effects of contemporary groups, cage location, and hen line, and the additive genetic, permanent environmental, and residual as random effects. In general, heritabilities were low to moderate (h 2 = 0.11 to 0.48). Genetic correlations among eggshell quality traits were moderate to high (0.36 and 0.69). High genetic correlations were obtained between the eggshell color traits [r g = -0.90 (L* and a*); r g = -0.64 (L* and b*); and r g = 0.65 (a* and b*)]. Results suggest that EW is strongly correlated with ESW, but the genetic correlations between EW and ESS and between EW and EST were low. Genetic correlations between L* and eggshell quality traits were low to moderate, suggesting that L* has little or no relation with external egg quality. However, genetic correlations between a* and b* values and eggshell quality traits were high. The genetic correlations between eggshell color and eggshell quality traits were low, suggesting that the eggshell color does not influence external egg quality. Genetic correlations between PROD and egg quality traits were negative and varied between -0.42 and -0.05. This antagonistic relationship emphasizes the importance of adopting breeding schemes that allow the simultaneous genetic progress of these traits by considering their genetic correlation and economic relevance, such as the selection index., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

The aim of this study was to evaluate the effect of organic selenium (SE) supplementation on blood constituents related to hematology and serum biochemistry of dairy goats in the productive phase. A total of 16 lactating Saanen × Toggenburg crossbred goats, aged between 2 and 3, lactating, nonpregnant, clinically healthy, and having a body weight (BW) of 40.75 ± 8.31 kg were selected for this study. Higher SE concentrations were observed on the 42 nd day of supplementation, and on the 63 rd day, the SE concentrations were similar ([Formula: see text]) to the 21 st and 42 nd days. There was no interaction for plasma constituents comparing treatment effects and days of supplementation ([Formula: see text]). SE supplementation reduced ([Formula: see text]) plasma proteins with a gradual increase in available SE. There was no difference ([Formula: see text]) for the blood count comparing the effects of treatment and days of supplementation. There was no interaction ([Formula: see text]) for serum biochemical constituents between treatments and periods, except for urea ([Formula: see text]). Animals that received SE supplementation had similar plasma urea concentrations before and after supplementation, while animals that did not receive SE in the diet had increased serum urea concentrations. The main action of selenium in metabolism occurred in the reduction of plasma proteins and urea levels, which leads us to conclude that it influenced protein metabolism. Finally, hematology, liver function, and energy metabolism are not affected by selenium supplementation in dairy goats reared in semiarid conditions., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

Selenium is an important element in nutrition, showing great potential in the udder health of dairy goats and in the control of subclinical mastitis. However, there are few studies that evaluated the influence of selenium supplementation on subclinical mastitis in goats. The aim of this study was to evaluate the incidence of subclinical mastitis in dairy goats supplemented with organic selenium (Se yeast) in a semi-arid region. Sixteen Saanen × Toggenburg crossbred lactating goats were allocated randomly into two treatments: with and without addition of organic selenium (Se) to the concentrate. Milk samples were collected every 20 days from each udder half to determine the somatic cell count (SSC), chloride content, pH, electrical conductivity, microbiological isolation, composition, and selenium contents. The highest serum selenium concentrations in the blood of these goats occurred at 42 days of supplementation (P < 0.001). Goats which received organic selenium supplementation had higher serum selenium concentrations (P < 0.05). The milk composition variables did not differ (P > 0.05) between the tested treatments, teats, and collections. After 60 days of supplementation, a difference was observed (P < 0.05) between treatments for SSC, chloride content, and pH. Addition of organic selenium to the diet of dairy goats after 60 days of supplementation was promising in reducing the somatic cell count, consequently improving milk quality., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

Given the current bans on the use of some growth promoting antibiotics in poultry nutrition, the need to use alternative additives which could replace traditional promoters in diets has arisen. The objective of this study was to evaluate the effect of alternative additives, associated or not, in replacing the antibiotic growth promoter in the diets of laying hens on performance, egg quality, biometry, bone characteristics, and economic viability. A total of 378 birds at 97 weeks of age, weighing 1691 ± 80g with an average production of 79.96 ± 4.9%, were randomly distributed and submitted to different diets: negative control - NC (no additive); positive control - PC, conventional growth promoter (Enramycin); associated organic acids (OA); symbiotic (S); Essential oil (EO); OA + S; and S+EO. The diet did not influence (P > 0.05) performance, egg quality, biometry, and bone traits. However, the use of alternative additives and their associations with the exception of S+OA, provided better economic indices when compared to NC and CP. The first component showed a negative relationship between feed conversion per mass and dozen eggs with gut length, Seedor index, egg production, and egg mass; the second component showed a positive relationship between yolk, pancreas, proventriculus, and gizzard; and, finally, the third component showed that feed consumption has a negative relationship with bone strength and deformity. The first two canonical functions were significant and discriminated 100% of the differences between the diets. Moreover, 50% of the birds were correctly classified in their group of origin, in which the positive control group (83.3%) and OA+S presented the highest rates of correct responses (66.7%). Bone deformity and bowel length were the only two variables with discriminatory power. Natural growth promoters alone or in association do not harm performance, egg quality, digestive organs biometry or bird bone characteristics, in addition to promoting greater economic return. Thus, they can be considered possible substitutes for traditional antibiotics. Finally, unsupervised machine learning methods are useful statistical techniques to study the relationship of variables and point out the main biomarkers of poultry production., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

Due to the high milk production of Holstein cows, many countries have chosen to import semen to improve local dairy herds. This strategy would be more effective if this semen was used in the same environment conditions in which the bulls were selected. If the effect of genotype by environment (G × E) interaction is not considered, the estimated breeding values (EBVs) may vary, potentially reducing the selection response. We evaluate the impact of heat stress on selection for milk yield and composition of Holstein cows using random regression models. To verify the interference of heat stress in milk yield (MY) and composition traits (fat, protein, total saturated, and total unsaturated fatty acids content in milk), temperature-humidity index (THI) on test-day milk records was used. The threshold value to divide the environments using test-day information from Brazilian Holstein cows was 72 units of THI, i.e., < 72 represented no heat stress and > 72 represented heat stress. Legendre polynomials of second-order (Leg 2) model and two lactation points (33 and 122 DIM) were used to estimate heritabilities and EBVs for five important dairy traits. The heritabilities of milk components and fatty acids were low (0.09-0.29), regardless of lactation period and degree of heat stress, with the exception of protein content (0.30-0.35). Fat content was the only milk component that was reduced according to the degree of heat stress and lactation period. The EBVs tended to decrease in heat stress conditions, thus animals with high genetic potential demonstrated evidence of G × E interaction. However, acclimatization of dairy cows to heat stress in the farm production systems may have been responsible for the low differences among genetic parameters and EBVs with and without heat stress found in this study., (© 2022. The Author(s) under exclusive licence to International Society of Biometeorology.)

Genomic tools can help in the selection of animals genetically resistant to heat stress, especially the genome-wide association studies (GWAS). The objective of this study was to compare the variance explained by SNPs and direct genomic breeding values (DGVs) at two levels of a temperature and humidity index (THI). Records of milk yield (MY), somatic cell score (SCS), and percentages of casein (CAS), saturated fatty acids (SFA), and unsaturated fatty acids (UFA) in milk from 1157 Holstein cows were used. Traditional breeding values (EBV) were determined in a previous study and used as pseudo-phenotypes. Two levels of THI (heat comfort zone and heat stress zone) were used as environments and were treated as "traits" in a bi-trait model. The GWAS was performed using the genomic best linear unbiased prediction (GBLUP) method. Considering the top 50 SNPs, a total of 36 SNPs were not common between environments, eight of which were located in gene regions related to the evaluated traits. Even for those SNPs that had differences in their explained variances between the two environments, the differences were very small. The animals showed virtually no rank order, with rank correlation values of 0.90, 0.88, 1.00, 0.88, and 0.97 for MY, CAS, SCS, SFA, and UFA, respectively. The small difference between the environments studied can be attributed to the small difference in the pseudo-phenotypes used between the environments, on-farm acclimation, the polygenic nature of the traits, and the THI values studied near the threshold between comfort and heat stress. It is recommended that future studies be conducted with a larger number of animals and at more extreme THI levels., Competing Interests: We certify that there is no conflict of interest with any financial organization regarding the material discussed in the manuscript.

This research evaluated the effects of using by-product from biscuit industry (BBI) in the diet of fattening lambs of Morada Nova breed. Lamb growth performances and carcass traits were investigated. Twenty Morada Nova breed male lambs body weight (BW) 17.1 ± 3.74 kg, single born, and age 141 ± 7 days were divided into four homogeneous groups (n = 5) fed for 8.5 weeks with four experimental diets replacing corn with BBI at 0, 150, 300, and 450 g/kg. Experimental diets were consisted of 30% Tifton-85 hay and 70% concentrate on dry matter (DM) basis. Diets were formulated to be isonitrogenous and isoenergetic in order to supply nutrient requirements of growing lambs with an average daily gain of 200 g/day. Increased feeding levels of BBI partially replacing corn did not affect dry matter intake, organic matter, and crude protein intake (P > 0.05). Animal performance was not affected by the dietary treatments (P > 0.05). BBI addition to the concentrate did not influence carcass traits, carcass measurements, quali-quantitative of Longissimus lumborum muscle, and meat cuts (P > 0.05). Partially replacing corn with a by-product from biscuit industry does not affect performance and carcass traits of fattening lambs. The BBI can partially replace up to 450 g/kg DM of corn on lambs' diets as a suitable agro-industrial by-product., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)

This study aimed to estimate the variance components and genetic parameters for body weight in tropical goats testing different models using Bayesian approach and investigate the effectiveness of fitting the effects of maternal genetic, permanent environmental, and covariance between direct and maternal effects. Records from 1980 to 2010 of 1453 Anglo-Nubian goats' herd were used. Six performance growth traits: birth weight (BW, kg), at 28 (W28, kg), 56 (W56, kg), 112 (W112, kg), 140 (W140, kg), and 196 (W196; kg) days of age, were evaluated. There was a negative covariance between direct genetic effects and maternal additive for all weights. The effect of maternal permanent environment is an important source of variation for performance characteristics in goats until the 196 days, and must be considered in genetic evaluation models in order to obtain accurate predictions of breeding values of individuals. The importance of inclusion of the additive maternal effect appears to be more dependent on the structure of the data set under evaluation. Given the structure of the data, the described management and criteria for choosing the best model (deviance information criterion and the Bayes factor) should make the estimation of parameters for weights at birth and at 28 and 56 days using model IV, since that will provide more consistent results than the type I (less complex), without the need of accurate representations of knowledge prior to data collection. Over time, the breeding program will have more data and thereby increase the possibility of building a prior distribution confident that would enable the inference of parameters for more complex models. However, these are preferable components for the estimation of the characteristics and weights to 112 at 140 and at 196 days, using model I (less complex)., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)

Knowledge on heat stress of animals is key to developing management strategies to mitigate its effects on livestock production. Efficiency and profitability of production systems will certainly be challenged by the forecasted global temperature increase of 1.5 °C between 2030 and 2050. Goats are a resilient animal model, much less affected by climatic variations than average livestock. However, this statement is only true to a certain threshold, which, if exceeded, may affect energy metabolism of goats thus affecting respiratory frequency, heart pulse, evaporative thermolysis and rectal temperature, also altering on hormonal profile of animals, leading to behavioural changes such as altering feed and water intake and sheltering in the quest for homeothermic status. Dairy goat breeds, such as Saanen, are more sensitive to heat stress. Adaptations in nutritional and environmental management, as well as selecting better adapted breeds are strategic practices targeting the mitigation of effects of thermal stress of goats in farming systems. However, studies on effects of ambient temperature on energy and basal metabolisms of goats are scarce. This review aims to elucidate energetic and basal metabolism responses of goats under heat stress targeting the development of management strategies to mitigate heat stress in the farming systems and the conservation of genetic resources, adaptability, phenotypic plasticity, and basal heat production in different breeds., Competing Interests: Declaration of competing interest There were no conflicts of interest., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

The economic feasibility of replacing corn grain with by-product from biscuit manufacture (BBM) as an energy source in the diet for purebred and crossbred native lambs raised in feedlot was evaluated. Four production systems were developed based on nutritional management and genetic groups: (PS 1 ) purebred native lambs fed a conventional diet based on corn and soybean meal; (PS 2 ) purebred native lambs fed a diet with BBM replacing 100% of the corn; (PS 3 ) crossbred native lambs fed a conventional diet based on corn and soybean meal; and (PS 4 ) crossbred native lambs fed a diet with BBM replacing 100% of the corn in the diet. The extrapolation was performed for a module of 24 Morada Nova (MN) breed lambs (12 MN red (MNR) and 12 ½MNR × ½MN white lambs)) with an initial body weight of 18.8 ± 0.875 and 15.0 ± 0.838 kg for MNR and crossbred, respectively. Feed, animal acquisition, and labor present the total production costs. The greatest profits were obtained in the production systems that fed the crossbred lambs with BBM. The lesser cost of BBM contributed to greater total factor productivity regardless of genetic group (1.095 vs. 1.015 for BBM and conventional feed, respectively). Systems using BBM (SP 2 and SP 4 ) showed an estimated payback of 5.44 and 3.24 years, respectively, while the use of conventional feed contributed to negative economic data (PS 1 and PS 3 ) with payback period greater than 10 years. The use of BBM as an energy source in the diet of crossbred sheep was economically feasible and showed better economic indices when compared to the systems using a conventional diet., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)

Feed restriction (FR) occurs commonly in sheep production systems in the Brazilian semi-arid region and can cause physiological changes in the progeny. We assessed the effects of the FR pre and postnatal on the performance and carcass traits of Morada Nova lambs. Twenty-four lambs born from a group of 68 ewes were distributed in three treatments of 8 replicates as follows: ewes fed ad libitum pre and postnatal (AL-AL); postnatal restriction (POSTN-R): included lambs born from ewes fed ad libitum in the last third of pregnancy with FR postnatal; and prenatal feeding restriction (PREN-AL): comprised lambs born from ewes subjected to FR in the last third of pregnancy but ad libitum postnatal. Slaughter body weight (20.96 kg); total weight gain (11.34 kg); average daily weight (0.096 kg); fasting carcass weight (19.45); hot carcass weight (9.33 kg); and cold carcass weight (9.11 kg) were smaller (P < 0.05) in POSTN-R but similar between AL-AL and PREN-AL. Rib (0.47 kg), shoulder (0.85 kg), loin (0.50 kg), and chest-flank (0.97 kg) had lower weight in lambs under POSTN-R (P < 0.05). The treatments did not affect the tissue composition of the 12th rib. The non-carcass components and carcass traits are the variables that best discriminate animals under FR plans. The postpartum FR in native lambs has an impact on the performance and carcass weight of the progeny, unlike lambs submitted to prepartum FR, which demonstrates the adaptation to intrauterine nutritional deficiency in Morada Nova ewes to produce lambs with heavy carcasses in regions semi-arid., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)

Investigations in the Brazilian semi-arid region evaluating the performance and carcass traits of sheep of indigenous breeds and their crossings have been performed; however, these studies use exotic breeds which produce precocious lambs with heavier carcasses, but not adapted to climatic conditions and the extensive production system, jeopardizing the sustainability of the sheep production system. We crossed between three indigenous breeds: Morada Nova (MN - maternal breed); Rabo Largo (RL - paternal breed), and Santa Inês (SI - paternal breed) with the objective of evaluating the effect of genotype and sex on the performance and carcass traits of purebred and crossbred animals. A total of 30 lambs, males and females, reared in a semi-intensive system were evaluated. Birth and weaning weights were 2.26 ± 0.53 and 7.31 ± 1.85, respectively. All lambs were slaughtered at 10 months of age. A completely randomized design in a 3 × 2 factorial scheme (three genotypes and two sexes) was used. Multivariate techniques were also performed to reduce group and discriminate variables. Birth and weaning weight were similar (P > 0.05) among genetic groups and sexes. The weight gain, carcass and morphometric trait characteristics, and the main commercial cuts were higher in crossbred lambs (P < 0.05). All indicators have discriminatory power between genotypes and sexes, but the carcass traits have a higher discriminatory power (P < 0.001). All genotypes, regardless of sex, have particular characteristics, i.e. MN × SI was characterized by greater forelimb and ham perimeters (P < 0.001), and the MN × RL by higher hot carcass weight and finish (P = 0.001). The cluster analysis and the heatmap plot revealed associations between SI and the size of cuts and RL with the cut commercial yield and the reduction in weight loss due to cooling. Our findings confirm the hypothesis that crossing between indigenous breeds represents an adequate alternative in sheep meat production systems in semi-arid regions. Finally, we encourage the use of indigenous breeds for sheep meat production with breed identity in order to favor the conservation of genetic resources and the sustainability of the production system., (© 2021. The Author(s), under exclusive licence to Springer Nature B.V.)

The relationship between hair color characteristics and thermoregulatory responses in ewes raised in hot environment were evaluated. 15 Santa Inês hair ewes of different genotypes associated with coat colors (light brown, dark brown and black) with body weight of 41.2 ± 8.1 kg were evaluated during three consecutive days. Rectal temperature (R T , °C) and coat surface temperature (C ST , °C) of seven anatomical points (front, back, croup, loin, side, thigh, and belly) were measured during the morning and afternoon periods. Thermoregulatory responses were recorded along with meteorological variables. Heat tolerance index (H TI ) and thermal gradient (T G , °C) were estimated for each genotype. R T and C ST were influenced by periods of the day ( P < 0.05), being higher in the afternoon, but T G did not differ ( P > 0.05) between periods. H TI , C ST , and T G were equal ( P > 0.05) among the three genotypes. Only R T was higher in animals with dark brown coats compared to light brown, but equal to the black coat. It was observed that animals with black or dark brown hairs have a strong association between the C ST under study, and yet these had an inverse behavior with the R T . Animals with a darker coat tend to trigger heat dissipation in various anatomical regions of the body, presenting dynamics in thermoregulatory responses in relation to those with lighter coats. Santa Inês ewes have heat dissipation mechanisms as a function of different genotypes associated with coat colors, but have the same thermoregulatory aspects to maintain homeostasis, demonstrating an excellent adaptive mechanism in a hot environment.

The aim of this study was to investigate the influence of environmental conditions and species on thermoregulatory responses, acid-base and electrolyte balance of black goats and ewes in an equatorial semi-arid environment. Ten Canindé goats and seven Morada Nova ewes with black coat color, all multiparous, aged between 2 and 3 years, non-lactating, non-pregnant, and body weight (B W ) of 22.84 ± 4.17 kg for goats and 22.60 ± 3.18 kg for ewes were used in this study. Air temperature (A T ) and relative humidity (R H ) were measured. Respiratory rate (R R ), Rectal temperature (R T ), sweating rate (S R ), hydrogen potential (pH), partial pressure of carbon dioxide (PCO 2 ), venous oxygen pressure (PO 2 ), bicarbonate (HCO 3 ), base excess (BE), total carbon dioxide concentration (TCO 2 ), venous oxygen saturation (SO 2 ), sodium (Na + ) and potassium (K + ) were recorded. Animal species (caprine and ovine) and environmental conditions (Thermoneutral condition, T C and Heat condition, H C ) were considered as fixed effects. Univariate and multivariate analysis techniques were used. Differences were observed between the two environmental conditions. Significant changes in all thermoregulatory responses for goats and ewes were observed according to the environmental condition effect. The general means of the species showed that only S R was high in ewes (P < 0.05), following a reverse change when compared to goat S R . For the environmental condition effect, only the blood pH of goats did not change under H C (P < 0.05), while the B E and TCO 2 did not change for ewes. The general means of PCO 2 , HCO 3 , BE, TCO 2 and SO 2 were higher in ewes compared to goats. For electrolytic balance, Na  +  demonstrated elevations in H C . Brazilian black goats and ewes raised in an equatorial semi-arid environment tend to have particular homeothermy, acid-base and electrolytic balance which mostly depend on the environmental conditions they are raised. The results support the changes in physiological mechanisms between black goats and ewes; however, both are locally adapted., (Copyright © 2021. Published by Elsevier Ltd.)

The objective of this study was to characterize and typify dairy farms and to evaluate society's perception of dairy production in rural settlements in the Brazilian semi-arid region. A questionnaire containing questions related to socioeconomic, livestock, physical, herd management, and production indicators was applied to 17 milk farmers for typological analysis. A second questionnaire was subsequently applied to the same 17 farmers for the holistic perception of dairy farming in rural settlements, in addition to 47 technicians in the area of animal science and 140 laypeople. Milk samples were collected in the settlement's community cooling tank, while the water used for milking management was collected in the milking parlor at the 17 farms. Multivariate analysis techniques and thematic analysis were performed. Three dairy production systems were identified: low production group (0-25 L), medium production group (25-50 L), and high production group (50-100 L). The physicochemical properties (composition, density, and cryoscopy) of milk attended the Brazilian regulation values. The microbiological parameters of milk and water used for milking are at odds with regulations. Regarding the typology, the indicators, livestock, and productivity showed discriminatory power (P < 0.05) between the productive systems. The responses from the segments of society showed different views on dairy production in rural settlements. It is concluded that the dairy farmers have low education and the cleaning product and water used in milking are out of regulation. The livestock and production indicators typified mainly dairy farms, while the holistic perception showed a lack of efficiency in rural extension, ignorance of the potential of the productive system. Finally, the creation of public policies focusing on the development of the milk production system in settlements is recommended., (© 2021. The Author(s), under exclusive licence to Springer Nature B.V.)

The aim of this study was to gain insights in respect to how locally adapted goats exhibit dynamic body heat in an equatorial semi-arid environment. Ten Canindé goats were used in the study (22.90 ± 2.70 kg). Respiratory rate (R R ; min breaths -1 ), rectal temperature (R T ; °C) and sweating rate (S R ; g m -2  h -1 ) were measured for 8 days, once a week, for 8 consecutive weeks in each animal, with collection intervals of 1 h throughout the day (24 h), together with the meteorological variables. Air temperature (A T , °C) and relative humidity (R H , %) were measured, and then, the temperature humidity index (T HI ) was calculated. First, we determined 2 days with stressful climatic conditions and similar environmental characteristics (day 1 and 2) among the 8 experimental days. The R T was evaluated on these 2 days using the means of each hour as the cut-off point, and determining whether the animals are efficient (EF) or inefficient (INEF) in heat loss (β 1 ) and gain (β 2 ). The R T was separated in β 1 and β 2 for 24 h, setting times to obtain the angular coefficients (β) for both. The days with stressful climatic conditions and similar environmental characteristics were day 1 and 2. The hours in which the Canindé goats gained and lost heat were respectively 11 a.m. to 3 p.m. and from 4 p.m. to 10 a.m. The animals classified as EF lost more or equal the amount of heat represented for R T . When the mean of all animals was evaluated for efficiency in heat control, the flock was classified as EF. Differences (P < 0.05) were observed for R R and S R between periods. The efficiency in dynamic body heat of the locally adapted goats in this study was determined and showed that the flock as a whole possesses an excellent heat dynamic in an equatorial semi-arid environment.

The objective of this study was to evaluate the thermoregulatory responses, acid-basic and electrolytic equilibrium of locally adapted goats under natural heat conditions in a semi-arid region. Ten (10) Canindé goats aged between 2 and 3 years, non-lactating, non-pregnant and having a body weight (B W ) of 22.90 ± 2.70 kg were used in this study. Air temperature (A T ) and relative humidity (R H ) were measured, and the radiant heat load (RHL) was subsequently calculated. Rectal temperature (R T ), respiratory rate (R R ), sweating rate (S R ) and heat shock (S) were recorded at 1-h intervals for 24 continuous hours. Hydrogen potential (pH), partial pressure of carbon dioxide (PCO 2 ), partial pressure of oxygen (PO 2 ), bicarbonate (HCO 3 ), base excess (BE), total carbon dioxide concentration (TCO 2 ), oxygen saturation (SO 2 ), sodium (Na + ) and potassium (K + ) were recorded at three moments during the day (5 a.m.; 1 p.m.; 6 p.m.). There were also significant differences between the means of hours of the day for A T and R H . R R was the thermoregulatory response which most closely followed RHL, with important elevations in the periods between 10 a.m. to noon. It was observed that the goats activated their SR mechanism before R R , more precisely between the hours of 9 a.m. and 1 p.m. The acid-base and electrolytic equilibrium for the goats which showed great association with the first components contributed the most to the total variation of the data. The most important variables in the adaptive profile of these animals in order of importance were: SO 2 , PO 2 , R R , R T , S R , HCO 3 , BE, TCO 2 and pH. An association between all variables grouped in each period was observed, where the thermoregulatory responses in the periods of 5 a.m. and 6 p.m. were closer than when compared to 1 p.m., showing a physiological return to the initial state. Therefore, the variation in thermoregulatory responses, acid-base and electrolytic equilibrium indicated that the goats have the ability to recover after a challenging environmental condition., Competing Interests: Declaration of competing interest The authors declare that they have no conflicts of interest., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The objective of this study was designed to evaluate the association between thermoregulatory responses, hormonal, hematological and serum biochemical values features aiming to propose an adaptability index (AI) for dairy cows under tropical conditions. Thirty adult dairy cows were used, including 15 Sindi and 15 Girolando breeds with mean weight of 338.52 ± 42.79 kg and 487.54 ± 60.67 kg, respectively. These data included rectal temperature (RT) and respiratory rate (RR). For the serum of blood sample, the levels of glucose (GLU), cholesterol (CHO), triglycerides (TRI), total protein (TP), creatinine (CRE), albumin (ALB), urea (URE), aspartate aminotrasferase (AST) and alanine aminotrasferase (ALT) and hormonal concentrations (triiodothyronine - T 3 and thyroxine - T 4 ). For the total blood samples were analyzed for hematology variables: red blood cell count (RBC); hemoglobin concentration (HC); packet cell volume (PCV); mean corpuscular volume (MCV); white blood cell (WBC). The AI was development using multivariate analysis to "weigh" the influence of each variable in the animal responses. The variables more important for adaptive aspects of Sindi and Girolando cows were respectively: GLU; MCV; AST; PCV; RBC; HE; TP; ALB; ALT; RR; T 4 ; RT; T 3 ; URE; CHO; TRI; CRE; WBC and ALB; GLU; TP; AST; RR; ALT; CRE; CHO; RT; RBC; T 4 ; HE; PCV; MCV; URE; TRI; WBC; T 3 . The difference between breeds was just over 8% for AI. We developed a preliminary AI, able to measure the level of adaptability of dairy cows under tropical region. The methodological framework has potential to inform decision-makers on the adaptability animal conditions and high inference of the blood values from adaptability of cows., Competing Interests: Declaration of competing interest The authors declare that they have no conflicts of interest., (Crown Copyright © 2020. Published by Elsevier Ltd. All rights reserved.)

The objectives of this study were to determine the main variables which act in the adaptive profile and the dynamic of the thermoregulatory responses of Sindi and Girolando dairy cows in tropical conditions using multivariate analyses as the auxiliary method. Thirty dairy cows were evaluated, in which the data were collected monthly during 12 months. Rectal temperature (R T ) and respiratory rate (R R ) were measured twice a day (morning and afternoon), along with meteorological variables (air temperature, relative humidity, and wind speed), and later the Black Globe and Humidity Index and Radiant Heat Load were calculated. Blood samples were collected for estimating the levels of triiodothyronine (T 3 ), thyroxine (T 4 ), hemoglobin concentration (HC), red blood cells (RBC), packet cell volume (PCV), mean corpuscular volume (MCV), white blood cells (WBC), glucose (GLU), cholesterol (CHO), triglycerides (TRI), creatinine (CRE), total protein (TP), urea (URE), albumin (ALB), aspartate aminotransferase (AST), and alanine aminotransferase (ALT). The more active variables in the adaptive profile for Sindi cows were T 4 , PCV, RBC, WBC, TRI, CRE, HC, T 3 , and URE, while PCV, RBC, ALB, TP, R T , R R , URE, ALT, and AST variables were more active for Girolando cows. All animals were classified according to their corresponding group when considering all variables under study. The classification error percentage was > 40% in the Sindi cows when the physiological responses were considered, whereas an 80% success rate was observed in Girolando cows in the winter and summer seasons. The physiological responses of the dairy cows are similar in winter and distinct in summer in tropical conditions.

Heat stress is one of the most important factors that affect the performance of some Bos taurus breeds and crosses in tropical regions. The Brahman breed was developed in hot regions of the world and often has genes that confer resistance to heat stress compared to other breeds of beef cattle. The goal of this work was to evaluate the adaptive responses of Brahman bulls, based on physiological, hormonal and hair characteristics according to season. The physiological, hormonal and hair characteristics were rectal temperature (R T ), respiratory rate (R R ), sweating rate (S R ), triiodothyronine (T 3 ), thyroxine (T 4 ), cortisol concentrations (C O ), coat thickness (C T ), hair length (H L ), hair diameter (H D ) and hair density (N D ). These were recorded in Brahman bulls from a Cerrado biome during four seasons: spring (21 September to 20 December), summer (21 December to 17 March), autumn (18 March to 20 June) and winter (21 June to 20 September). Data was analyzed using a general linear model that included season as a fixed effect; in addition, multivariate tests and logistic regression were also used to characterize the animals within each season. The meteorological variables defined the four seasons, besides identifying climatic differences between them. Significant differences (P > 0.05) were found for most of the physiological, hormonal and hair characteristics according to season. The Brahman bulls presented particular adaptive characteristics in each season. Individually, most of the Brahman bulls presented the same adaptive reaction in each season; particular similarity occurred for the summer and autumn. This pattern is a reflection of the inter-relationships between physiological responses and hair characteristics., (Copyright © 2019. Published by Elsevier Ltd.)