The sheep farming has economic and sociocultural importance in semi-arid regions worldwide. Of the total of 1.2 billion sheep in the world, 0.4 are found in semi-arid regions. In this review, we have discussed the main risk factors for neonatal lamb mortality and its association with the prevailing environmental conditions of tropical semi-arid regions. Over the last decades, the average mortality rate of newborn lambs remained relatively constant (~15%) around the world. This rate is reported to be higher (Up to 30%) in small-scale sheep farming systems from developing countries. Overall, the main risk factors of neonatal mortality include low birth weight, dystocia, adverse weather conditions, inadequate milk, or colostrum supply, competition between siblings in multiple births, and poor expression of maternal behaviour. In tropical semi-arid regions, recent findings revealed that newborn lambs from hair coat sheep breeds are less vigorous to perform the first suckling when even exposed to moderate cold conditions (18–20°C). On the other hand, the high radiant heat load in these areas can also challenge the thermoregulation of ewes and newborn lambs, especially if they are kept in areas without protection against direct short-wave solar radiation. Under such circumstances, newborn lambs were reported to be hyperthermic. The heat stress as risk factor for neonatal lamb mortality is a topic that deserves more investigation, particularly in tropical semi-arid areas, where is expected to be drier and hotter as consequence of rapid advances in climate change.

The work aimed to evaluate the effect of lactic acid bacteria, natamycin and hexanoic acid on the fermentation quality, aerobic stability and in vitro digestibility of total mixed ration (TMR) silages containing water bamboo sheath leaves. The treatments were as follows: (1) no additives (control, C), (2) lactic acid bacteria (L), (3) natamycin (N), (4) hexanoic acid (H), (5) lactic acid bacteria + natamycin (LN), (6) lactic acid bacteria + hexanoic acid (LH). Silos were opened and silages were evaluated to assess fermentation quality, aerobic stability and in vitro digestibility. All TMR silages were well-preserved as indicated by dominant lactic acid content, low ammonia nitrogen/total nitrogen, trace propionic acid and negligible butyric acid contents. All additives improved the fermentation quality and in vitro digestibility, evidenced by higher lactic acid/acetic acid ratio, lactic acid, acetic acid, water-soluble carbohydrate contents and lactic acid bacteria count, and lower pH, aerobic bacteria and yeast counts. The LN had the highest lactic acid, acetic acid, lactic acid/acetic acid ratio, in vitro gas production and in vitro digestibility. During aerobic exposure, the LN silage had the highest lactic acid and acetic acid contents, and the lowest pH among all TMR silages. The LN and LH prolonged aerobic stability, reaching 85.5 and 81.5 h, respectively. The LN is recommended to improve the fermentation quality, aerobic stability and in vitro digestibility of TMR prepared with water bamboo sheath leaves.

Interest in organic agriculture worldwide is growing and is mainly supported by a strong consumer interest. In the literature, a lot of attention has been paid to comparing organic and conventional systems, on studying the yield gap between the two systems and, how to reduce it. In the present work, based on the results from Polish organic and conventional series of field trials carried out in 2019–2021, organic and conventional systems were compared in terms of potato tuber yield. Moreover, we propose a Bayesian approach to the variety × environment × system data set and describe Bayesian counterparts of two stability measures. Using this methodology, we identify the most stable and highest tuber yielding varieties in the Polish potato organic and conventional series of field trials. It is shown that the tuber yield in the organic system was approx. 44% lower than the tuber yield in the conventional system. Moreover, varieties Tajfun and Otolia were the most stable and highest yielding varieties in the organic system, whereas in the conventional system, the variety Jurek was the most stable and highest yielding variety among the tested varieties. In the present work, the use of the Bayesian approach allowed us to calculate the probability that the mean of a given variety in given system exceeds the mean of control varieties in that system.

The objective was to evaluate steer performance, meat nutritional value, land-use, food–feed competition and both economic and environmental sustainability within temperate pasture-based suckler weanling-to-beef systems with or without (forage-only) concentrates. Post-weaning, 8-month-old, late-maturing breed steers (333 kg) were assigned to one of three systems: (1) grass silage + 1.2 kg concentrate DM (148 days), followed by pasture (123 days) and finished on ad libitum concentrates (120 days) – slaughter age, 21 months (GRAIN); (2) as per (1) but pasture (196 days) and finished on grass silage ad libitum + 3.5 kg concentrate DM (124 days) – slaughter age, 24 months (SIL + GRAIN); and (3) grass silage-only (148 days), pasture (196 days), silage-only (140 days) and finished on pasture (97 days) – slaughter age, 28 months (FORAGE). The mean target carcass weight was 390 kg for each system. Data generated were used to parameterize a farm-level beef systems model. Concentrate DM intake was 1187, 606 and 0 kg/head for GRAIN, SIL + GRAIN and FORAGE, respectively. The forage-only (FORAGE) system offers several advantages, including improved farm profitability, enhanced meat fatty acid profile and only utilized inedible human feed. Consequently, associated greenhouse gas (GHG) emissions per net human edible food produced were more favourable for FORAGE. However, compared to GRAIN, the FORAGE system had an older age at slaughter and associated increased pasture land-use and GHG emissions per animal, meat weight gain and essential amino acids gain. There are therefore inevitable trade-offs, as one beef system does not improve all sustainability and GHG emission metrics.

Crabgrass (Digitaria spp.) is an annual summer grass capable of self-reseeding and can provide forage with high nutritive value. However, knowledge is still limited about crabgrass management. Our objective was to compare the forage accumulation (FA) and nutritive value of two crabgrass varieties (Mojo and Quick-N-Big) for 2 years under combinations of nitrogen rates and harvesting management. The experimental design was in randomized complete blocks with five treatments and three replications for each crabgrass variety, totalling 15 experimental units for Mojo and 15 for Quick-N-Big, in adjacent fields. Treatments were combinations of nitrogen rates (0, 112, and 224 kg N/ha) and harvest management (harvesting once or twice during the growing season). Nitrogen fertilization increased FA in Mojo and Quick-N-Big. The combination of two harvests and 224 kg N/ha (H2N224) resulted in a total forage accumulation (TFA) of 7840 kg DM/ha/yr for Mojo in 2020 and 8550 kg DM/ha/yr for Quick-N-Big in 2021. The H2N224 management also resulted in the highest crude protein (CP) accumulation. Nitrogen fertilization accelerates plant maturity, which can increase neutral detergent fibre (NDF). In this case, harvesting twice stimulates new tissue production, limits NDF and increases CP and total digestible nutrients (TDN). Therefore, increasing harvesting frequency (twice during the growing season) as N is input increases TFA, CP and TDN, and also enhances N recovery, which may contribute to reducing animal supplementation costs and improve the economic return of forage-based livestock systems.

The milk production is strongly influenced by the dairy cow welfare related to a good nutrition and the analysis of the digestibility of feeds allows us to evaluate the health status of the animals. Through faeces’ visual examination it is possible to estimate the quality of diet fed in terms of lacking in fibre or too high in non-structural carbohydrates. The study was carried out in 2021, on four dairy farms in central Italy. The purpose of this work is the classification and evaluation of dairy cow faeces using RGB image analysis through an artificial intelligence (AI) (convolutional neural network (CNN)) algorithm. The main features to analyse are pH, colour and consistency. For the latter two RGB imaging was combined with deep learning and AI to reach objectivity in samples’ evaluation. The images have been captured with several smartphones and cameras, under various light conditions, collecting a data set of 441 images. Images acquired by RGB cameras are then analysed through CNN technology that extracts features and data previously standardized by a faecal score index assigned after a visual analysis and based on five classes. The results achieved with different training strategies show a training accuracy of 90% and a validation accuracy of 78% of the model which allow us to identify problems in bovine digestion and to intervene promptly in feed variation. The method used in this study eliminates subjectivity in field analysis and allows future improvement of increasing the data set to strengthen the model.

In pasture-based grazing systems, farm roadways are a pivotal link to connect paddocks on the grazing platform to the milking parlour. However, their effectiveness in the efficient movement of the dairy herd between the grazing paddocks and the milking parlour has yet to be fully quantified. A validation experiment was conducted on a research farm to analyse characteristics on farm roadways that may affect cow throughput, which was observed as the number of cows per minute (CPM) passing a specified location. Roadway width (R2 = 0.96) and surface condition score (SC) (R2 = 0.78, respectively) were both positively associated with CPM. Public road crossings imposed a 32.7% reduction in CPM in this study. CPM increased from 12.4 CPM on a one-metre-wide roadway with a SC of Index 1 to 107.6 CPM on a five-metre roadway with a SC of Index 5. This exercise allowed for CPM on commercial farms to be predicted. Farm roadways were examined across 55 Irish dairy farms. Greater roadway width, reduced verge width and greater water run-off were each associated with higher SC on commercial farms. Larger herd sizes had a lower CPM relative to herd size in contrast to smaller herd sizes, resulting in a significantly longer total time to move the dairy herd through any specific point on the farm roadway network. The findings from this study have quantified the parameters which affect both CPM on commercial farm roadways and parameters which may be associated with SC on commercial farm roadways.

The current study investigated the effects of pre-grazing herbage mass (PGHM, 1500 or 2500 kg dry matter (DM)/ha) and post-grazing sward height (PGSH, 4 or 6 cm) on herbage production and its nutritive value and DM intake, grazing behaviour and growth of Charolais steers (n = 96; 12 months of age; 396 ± 19.0 kg) during a 222-day grazing season, and the subsequent effect of an indoor finishing diet (grass silage alone or supplemented with concentrates) for 146 days, on performance and carcass traits. Steers were assigned to one of 12 grazing groups and group was assigned to a 2 (PGHM) × 2 (PGSH) factorial arrangement of treatments. At the end of the grazing season, live-weight was 16 kg heavier for PGHM-1500 than PGHM-2500 and 34 kg heavier for PGSH-6 than PGSH-4. After indoor finishing, there was no difference in carcass weight between PGHM treatments, but PGSH-6 had a 19 kg heavier carcass than PGSH-4. Herbage production was 881 and 517 kg DM/ha greater for PGHM-2500 than PGHM-1500 and for PGSH-4 than PGSH-6, respectively. Grazing stocking rate did not differ between PGHM treatments but PGSH-4 carried 1.35 more steers/ha than PGSH-6. Supplementing concentrates during the indoor period increased carcass weight (42 kg) and fat score (2.10 units). In conclusion, grazing to 6 rather than 4 cm, increased individual carcass weight but not carcass weight gain/ha. Compared to PGHM-2500, grazing PGHM-1500 increased steer live-weight gain at pasture, but did not affect carcass weight following indoor finishing.

The aim was to study the effect of the threshold number on the accuracy of genomic evaluation of the threshold traits using support vector machine (SVM), genomic best linear unbiased prediction (GBLUP) and Bayesian method B (BayesB). For this purpose, a genome consisting of three chromosomes was simulated for 1000 individuals on which 3000 bi-allelic single nucleotide polymorphism markers were evenly distributed. Genomic breeding values were predicted in different scenarios of threshold number (1–6 thresholds), QTL number (30 and 300 QTLs) and heritability level (0.1, 0.3 and 0.5). By increasing the number of thresholds from 1 to 6 thresholds, especially at higher levels of heritability, the accuracy of genomic evaluation increased; however, the increase in accuracy was not linear so that it was much more noticeable when the number of thresholds increased from 1 to 2 thresholds. In the most studied scenarios, SVM showed a very poor performance compared to other methods. BayesB ranked first regarding prediction accuracy, though in some cases the observed differences with GBLUP was not significant. While increase in heritability increased the accuracy of genomic evaluation, change in the QTL number had a slight effect on the prediction accuracy. According to the results, the SVM is not recommended for genomic evaluation of threshold traits, especially those which have only one threshold and instead, use of GBLUP and BayesB is recommended. For traits with more than one threshold, fortunately we can achieve accuracy similar to continuous traits by applying traditional genomic evaluation methods.

The objective was to evaluate energy partitioning and predict the relationship between metabolizable energy (ME) and digestible energy (DE) in hair sheep fed tropical diets at three feeding levels (maintenance, intermediate and high). To evaluate the energy partition, a database with 114 records (54 non-castrated males and 60 females) from comparative slaughter studies was used. To estimate the ratio ME:DE, 207 observations (74 non-castrated males and 133 females) were used from six studies in a multi-study approach, two indirect calorimetry studies (n = 93) and four comparative slaughter (n = 114), using a mixed model and study as random effect. A simple linear regression equation of the ME against DE was fitted to predict the efficiency of DE to ME conversion. Gas losses were greatest (P < 0.05) for animals fed at maintenance level (7.92% of gross energy intake). The variations of energy losses in the urine were 2.64, 2.06 and 2.08%; faecal losses were 34.37, 37.80 and 36.91% for maintenance, intermediary and high level of feeding, respectively. The regression analysis suggested a strong linear relationship between ME and DE, generating the model ME (MJ/day) = −0.1559 (±0.07525) + 0.8503 (±0.005864) × DE (MJ/day). This study highlights the importance of the relationship ME:DE. Equation/factor 0.85 presented herein is alternative that could be used for the calculation of ME from DE in feedlot diets tropical. In conclusion, we suggest that for hair sheep fed tropical diets the conversion factor 0.85 is more adequate to predict ME from DE.

This study aimed to quantify a latent variable for body size (BS) in pigs by using five linear body measurements including body length (BL), body height (BH), chest width (CW), chest girth (CG) and tube girth (TG), and also to identify the most associated single nucleotide polymorphisms (SNP) and related genes with BS by using the genomic best linear unbiased prediction (GBLUP) based genome-wide association study (GWAS) or GBLUP-GWAS methodology. To perform a GWAS on the BS latent trait, we used a mixed linear model and identified a total of 53 significant SNPs. Additionally, we found that nine genes, including Rho GTPase activating protein 12 (ARHGAP12), transmembrane protein 108 (TMEM108), T-cell lymphoma invasion and metastasis inducing factor 1 (TIAM1), ras homologue gene family member B (RHOB), POU class 4 homeobox 1 (POU4F1), follistatin-related protein 4 (FSTL4), cellular communication network factor 2 (CCN2), beaded filament structural protein 2 (BFSP2) and attractin-like protein 1 (ATRNL1) were associated with the BS trait in pigs. These genes are involved in several biological processes, including the regulation of anatomical structure, morphogenesis, the regulation of cell size and growth. The results suggest that the identified SNP and related genes may play important roles in regulating the growth and development of pigs. The results imply that these genes could be promising candidates for further exploration of the underlying mechanisms of body size variation. Furthermore, the findings have significant practical implications for enhancing the efficiency and profitability of pig farming through genetic selection.

The optimal feeding time of microencapsulated sodium butyrate (SB) in whole milk (WM) and starter feed on growth performance and health in dairy calves was evaluated. Forty-eight newborn Holstein calves (body weight (BW) = 39.45 ± 2.48 kg) were randomly assigned to one of the four treatment groups (12 calves per treatment; seven females and five males) in a complete randomized block design and fed (1) WM without microencapsulated SB (CON) supplementation; (2) 4 g/day SB added to WM since days 4–32 (SB-4-32); (3) 4 g/day SB added to WM since days 61–74 and an equal amount was added to starter since days 75–88 (SB-61-88) and (4) 4 g/day SB added to WM since days 4–74 and an equal amount was added to starter since days 75–88 (SB-4-88). Total dry matter intake, starter intake, BW, average daily gain and gain-to-feed were similar between treatments. Calves fed SB-4-32, and SB-4-88 had lower faecal score during pre-weaning, and overall. In addition, calves in SB-4-32 and SB-4-88 groups had fewer numbers of days with scours during the pre-weaning period, and throughout the study. Calves fed SB-61-88 had greater serum total protein during post-weaning. Post-weaning and overall albumin concentrations were greater in SB-4-32 and SB-4-88 calves and tended to be greater in the pre-weaning period compared to control calves. In general, the time of SB addition had no remarkable effect on performance but better faecal score within the pre- and post-weaning periods.

The intensification of production systems raises concerns about animal welfare. In egg production, the use of cages is the main reason for discussion. The current transition from the production system to cage-free systems raises questions about consumer perception. The objective of this study was to typify, characterize and differentiate the profile of Brazilian consumers regarding animal welfare in laying poultry. For this, a questionnaire with 28 questions, addressing questions about sociodemographic indicators (SOC), eating habits (HAB), knowledge about the production chain (CON), general perception of animal welfare in egg production (HPW) and about eggs with an animal welfare guarantee (PEAWG) was answered by 1415 consumers. Machine learning techniques were applied to characterize; typify and holistic perception. Three groups of consumers were defined: interested, emerging and indifferent. All indicators under study showed discriminatory power (P < 0.001). The indicators that showed the greatest importance for the classification of the three profiles were HPW < EHAB < COM < PEAWG < SOC. The results indicate the potential of interested and emerging groups to become consumers of cage-free eggs and also indicate the need to inform the population about animal welfare in egg production. The results reinforce the need to create specific public policies for the production chain, in order to value egg production and reaffirm interest in the area, especially in specific niches such as production in cage-free systems.

In meat-type poultry breeding, pectoral angle (PA) is a conventional anatomical indicator for changes in body conformation and meat traits; its correlation to egg performance is however deemed controversial. In this context, we revisited, assessed and put forward evidence for the usefulness of this classic phenotypic variable and its specific integrative index of pectoral angle-to-body weight ratio (PA/BW). Specifically, we identified respective correlations and used them for distinguishing the major categories (production types) of diverse chicken breeds under the traditional classification model (TCM) and genotypic clustering models of the global chicken gene pool subdivision. Also, the usefulness of the supplementary integrative egg mass yield index (EMY) for this objective was demonstrated. Because of estimating the total mass of eggs laid (i.e. egg number times egg weight), EMY can serve as an indicator of egg production. Direct approximation of EMY values by PA and BW values did not lead to significant correlation dependences between these indicators in each of the four breed utility types according to TCM. However, using the ratio of PA to BW, instead of PA and BW alone, resulted in significant correlation of EMY with PA/BW, allowing for distinction between egg-type and non-productive breeds. The validity of the proposed correlation-based models was supported by PCA and Neighbor Joining clustering analyses. Collectively, we suggested that PA can be a potentially correlated trait for selecting hens and roosters in breeding flocks to boost egg yield. These results can also be applied to chicken breeding as well as conservation- and phenome-related research.

Medicinal plants with high phytochemical values are critical for enhancing the productivity of livestock systems, while reducing their environmental impact. This study investigated the influence of graded levels of Cassia fistula leaf powder (CFLP) on in vitro ruminal fermentation parameters, gas production and degradability of diets for ruminants. Five concentrate diets were formulated to contain varying levels of CFLP (0, 15, 30, 45 and 60 mg/g dry matter (DM), denoted CF0, CF15, CF30, CF45 and CF60, respectively). The concentrate diets combined with guinea grass hay at the ratio of 4 : 6 (concentrate : forage) served as a substrate for the study. In vitro gas production test was performed by incubating 200 mg DM of the substrate for 48 h. At the end of the incubation period, the total gas and methane production, nutrient digestibility, in vitro fermentation and post-incubation parameters were evaluated. Results revealed a linear decrease (P < 0.001) in gas and methane production across the treatment groups with an increase in CFLP levels. The amount of methane produced varied from 9.3 ml/200 mg DM in the CF60 diet to 20 ml/200 mg DM in the control diet. Nutrient digestibility was highest in the control diet and lowest in the CF60 diet. There was a linear decrease in ammonia-nitrogen and total volatile fatty acid (TVFA) concentration with an increase in the CFLP level. Inclusion of CFLP up to 30 mg/g DM ruminant diet was found to reduce methane production and ammonia-nitrogen concentration with minimal effects on nutrient degradation and TVFA concentration.

There is a need for a low-cost strategy that accelerates the genetic change in local chicken breeds. Therefore, the objective of this study is to develop a strategy for marker-assisted selection for growth in local chickens in the developing countries. The studied lines were a homozygous normally feathered selected line (CE1), homozygous naked-neck selected line (CE3) and their corresponding control lines (CE2 and CE4). Lines CE1 and CE3 have been selected for high 6-week body weight (BW) for five generations. Three generations were obtained for this study. In the current study, we consider the 6th generation as the base generation for marker-assisted selection study. Two subsequent selected generations were obtained from the base generation. The selected lines were significantly heavier at 6 weeks of age than their corresponding control lines by 24.15 and 27.07% in the base generation and by 51.4 and 34.5% in the second selected generation. A total of 34 polymorphic alleles in 19 loci were flown over generations and the flow trends were different in different lines and families within lines. Principal component analysis was applied to the data of both lines and two main components were found and three canonical correlations were obtained. Four and five alleles were persistently concomitant with the highly performed families in lines CE1 and CE3, respectively. These alleles would have brought 6-week BW into higher levels of performance by 25.1 and 16.6% in the second generation if they would have been considered in the selection for 6-week BW.