Search Results (147)

This study comprehensively explores the environmental implications of two feeding strategies in pig farming, focusing on three scenarios: Brazilian tables (BT-2017), NRC (NRC-2012), and AGPIC (AGPIC-2021). The comparison involves conventional phase-feeding (CON) and the daily fit model (DFM). The five-phase system provided the same diet to all pigs within a group during each proposed phase. In contrast, the DFM adjusted the diet based on the nutritional requirements of pigs, anticipating subsequent diets through daily adjustments. We employed a cradle-to-gate approach, with the functional unit defined as one barrow with an initial body weight of 20.61 ± 0.85 kg, raised to 138.94 ± 0.90 kg over a 120-day growing-finishing period. Input data were sourced from observed commercial records from pig farms in Brazil, including over 1,000,000 data points from pigs raised under standard industry conditions. We evaluated the impact of the life cycle by considering factors such as acidification, climate change, ecotoxicity, eutrophication, land use, resource use, and water use. The OpenLCA software (version 1.11.0) and the Environmental Footprint 3.0 impact assessment method were used. Our results indicate that the DFM consistently outperforms the CON strategy in terms of reducing environmental impacts. Among the three scenarios, BT-2017 results in higher environmental impact reductions compared with NRC-2012 and AGPIC-2021. This is due to the higher concentration of corn and soybean meal in diets. Notable reductions include in relation to land use-related climate change impacts (12.55%), freshwater eutrophication (6.21%), mineral and metal resource depletion (6.11%), and fossil resource use (4.88%). These findings highlight that even modest adjustments to feeding strategies can effectively reduce the environmental footprint of pig farming. Full article

This 2 × 2 factorial study examined the welfare and performance of finishing pigs at two group sizes (9 or 18 pigs) over 12 weeks. For each set of groups of either 9 or 18 pigs, half of the pigs in each group size were fed ad libitum, while the others received a mildly restricted ration. Treatments were assigned to 16 partially slatted floor pens in a randomized block design, with a floor space of 1.15 m²/pig. Except in Week 1, there were proportionally fewer pigs with ear (p = 0.020) and tail (p < 0.0001) bite marks in groups of 18 than in groups of 9. Ear bite marks declined over time in both group sizes (p < 0.0001). There was also a significant interaction between group size and week regarding severe bite marks on the ears (p < 0.0002). Tail bite mark prevalence increased over time in the smaller groups but decreased in the larger groups (interaction: p < 0.001). A higher proportion of pigs in smaller groups sought human contact in Weeks 1 and 6, but this measurement equalized by Week 10 (interaction: p = 0.008). There were proportionally more pigs with tucked tails in the smaller groups in Week 1 but not in later weeks (interaction: p < 0.0001). Group size did not influence pig cleanliness or locomotion disorders. Ad libitum (vs. restricted) feeding increased average daily gain (p < 0.001), feed intake (p = 0.002), and slaughter weight (p = 0.030). Results suggest better welfare in the larger than in the smaller groups. Full article

Automated pig-welfare monitoring needs scalable, non-invasive signals that work across ages and individuals. A key methodological contribution of this study is the use of subject-wise validation, which ensures generalization to unseen animals and prevents inflated accuracy caused by growth-related and individual ‘voice’ differences. Vocalizations can help, but growth and individual “voice” differences can confound distress patterns and overstate accuracy without subject-wise validation. In our study, we explicitly accounted for individual variability by including animal identity as a random effect in mixed models and by using grouped cross-validation, where models were tested only on pigs not seen during training. This approach ensures that the reported accuracy reflects generalization across different individuals rather than memorization of specific vocal signatures. We analyzed 2221 vocal samples from 40 pigs (20 males, 20 females) recorded across four growth phases (farrowing, nursery, growing, finishing) under six conditions (pain, hunger, thirst, cold stress, heat stress, normal). Acoustic features extracted in Praat included energy, duration, intensity, pitch, and formants (F1–F4). Using blockwise variance decomposition, we quantified contributions of distress exposure, growth phase, and sex, and estimated the additional variance explained by animal identity. Distress exposure dominated intensity and spectral traits, particularly Formant 2, whereas the growth phase produced systematic shifts in duration and pitch. Animal identity added a modest but consistent increment in explained variance (~+0.02–0.03 R² beyond sex, phase, and distress). For prediction, we used 5-fold cross-validation grouped by animal. A Random Forest achieved a modest balanced accuracy of 0.609 and macro-F1 of 0.597; pain was most separable (recall 0.825), while other states showed moderate recall, indicating overlap. These results support hierarchical acoustic encoding of distress and establish a benchmark for precision welfare monitoring. Furthermore, they highlight that resolving complex physiological overlaps, such as heat stress and resource competition, requires a shift from unimodal acoustic models to multimodal Precision Livestock Farming (PLF) systems that integrate bioacoustics with continuous environmental and behavioral data streams. Full article

Accurate and physiologically relevant in vitro models are needed to predict nutrient digestibility and hindgut fermentation in pigs, as conventional in vivo trials are resource-intensive and raise animal welfare concerns. This study evaluated and compared the predictive performance of three in vitro digestion approaches—shaking (S), dialysis (D), and a combined shaking plus dialysis (SD) method—for estimating in vivo apparent total tract digestibility (ATTD) and fermentation characteristics across weaning, growing, and finishing pigs. Commercial diets were subjected to simulated gastric and small-intestinal digestion using S, D, or SD, followed by fecal inoculation to model hindgut fermentation for 12 and 48 h. During the gastrointestinal phase, crude protein digestibility was highest with D (>75%), intermediate with SD, and lowest with S (50–60%), indicating that product removal by dialysis mitigated enzyme inhibition from metabolite accumulation. After 48 h of fermentation, all methods showed strong linear correlations with in vivo ATTD (r > 0.93), but only D achieved high absolute agreement (Lin’s CCC > 0.95 for dry matter and crude protein). Moreover, D and SD at 48 h closely reflected in vivo fecal profiles of skatole, indole, and microbial enzyme activities, with D at 12 h showing an especially strong correlation for protease (r = 0.98). While D provided the most precise predictions of absolute values, the SD method offered an optimal balance between physiological relevance and operational efficiency, supporting its use as a robust, high-throughput platform for porcine feed evaluation and fecal nitrogenous odorant prediction. Full article

In intensive commercial pig production systems, the spatial distribution of elimination and lying behaviors plays a crucial role in pen hygiene, management efficiency, and animal welfare. Pen partition design and the provision of hiding facilities are key structural factors that may influence pigs’ spatial preferences; however, systematic evaluations of their combined effects remain limited. A total of 108 growing–finishing pigs were used in a 3 × 2 factorial design to assess the effects of different partition types and hiding facility configurations, as well as their interaction, on the spatial distribution of elimination and lying behaviors. Behavioral data were analyzed using non-parametric statistical methods. The results showed that partition type and hiding facilities significantly influenced the spatial patterns of elimination and lying behaviors (p < 0.05), whereas no significant effects were observed on total daily elimination duration, elimination frequency, or lying posture distribution (p > 0.05). Elimination behavior was predominantly concentrated in the slatted floor area. The combination of a front-closed partition with a hiding facility significantly increased the proportion of disturbed elimination events (16.2 ± 14.3%), which was higher than that observed in the open partition combined with a hiding facility (7.9 ± 7.6%, p < 0.05). In contrast, the rear-closed partition design was associated with atypical elimination occurring on the solid floor area. Overall, pigs showed a clear preference for lying on the solid floor. The front-closed partition combined with a hiding facility significantly reduced the proportion of lying on the solid floor (64.6 ± 8.5%), whereas the open partition combined with a hiding facility resulted in a higher-than-average proportion of solid-floor lying behavior (80.6 ± 8.9%). These findings indicate that an open partition design combined with a hiding facility is more effective in maintaining functional separation between elimination and resting areas while reducing disturbed elimination events. This study provides experimental evidence to support structural optimization of growing–finishing pig housing, contributing to improved pen hygiene and enhanced animal welfare. Full article

In intensive pig production systems, limited space and lack of enrichment materials (EMs) restrict natural behaviors, inducing chronic stress and impairing welfare and health. Conventional EMs such as straw and sawdust improve comfort but increase NH₃ and particulate emissions and hinder manure management on slatted floors. This study compared rice-straw silage (RS), sawdust (SD), and sling belt (SB) as EMs for growing-finishing pigs to evaluate their effects on growth performance, behavior, body lesions, cleanliness score of body, and pen air quality. A total of 344 crossbred pigs ([Landrace × Yorkshire] × Duroc, 30.5 ± 3.10 kg) were randomly allocated to four treatments: Control, 50% slatted and 50% solid flooring; RS, 100% solid flooring with a 7-cm layer of RS; SD, 100% solid flooring with a 7-cm layer of SD; SB, 50% slatted and 50% solid flooring with 10 SBs (1.5 m long and 75 mm wide). At week 10, the RS pigs had the lowest body weight. At week 0, the RS and SD pigs exhibited more positive behaviors, although the SD pigs also showed the highest number of injurious interactions at week 3. Between weeks 0 and 5, the SD pigs spent less time lateral lying and more time sternal lying, while during weeks 8–11, sitting was more prevalent. Both RS and SD groups exhibited lower cleanliness scores at week 6 and higher NH₃ and CO₂ levels at week 10. In conclusion, bedding materials such as RS and SD promoted positive behaviors during the early phase; however, prolonged use without adequate management impaired hygiene, air quality, resting behavior, and growth performance. These findings highlight the importance of the appropriate selection and management of EMs in intensive pig production systems. Full article

This study aimed to investigate the effects of partially replacing corn with rice in the diet and supplementing with cellulase on growth performance, pork quality, and gut microbiota of growing–finishing pigs. A total of 64 healthy pigs (68.03 ± 1.59 kg) were randomly assigned into four groups: CON (basal diet), ASE (basal diet + 20,000 IU/g cellulase), RICE (the basal diet replaced 50% of corn with rice), RASE (the basal diet replaced 50% of corn with rice + 20,000 IU/g cellulase). The results indicated that dietary rice and cellulase, either individually or in combination, had no significant effects (p > 0.05) on the FBW, ADG, ADFI, and F/G of pigs. However, the dietary rice markedly increased the intramuscular fat (IMF) content (p < 0.05). Furthermore, gut microbiota profiling indicated that Papillibacte were enriched in the RICE group and positively associated with IMF content. Metabolomic analysis revealed substantial differences in fecal metabolites among the treatment groups. The RICE group exhibited reduced levels of Zygadenine, Carpaine, and Rhodioloside E, which were negatively correlated with both IMF content and Papillibacter. In conclusion, dietary rice can promote IMF deposition by modulating gut microbiota and host metabolism, without compromising the growth performance of pigs. Full article

Crude protein (CP) decrease coupled to amino acid (AAs) supplementation is interesting for swine nutrition. A proteomics approach unraveled physiological events underlying differences between sexes fed two diets: control and low CP in fast-growing Duroc X (Landrace X Large white) finishing pigs. Sixty animals per sex were distributed in pens (five replicate pens/group), fed ad libitum with two isoenergetic diets (145 vs. 125 g CP/kg with AA supplementation; control and low-CP) for 42 days. Semimembranosus muscle was sampled. Five samples per group were used for Label Free proteomics. Four comparisons were considered: Control Males vs. Control Females; Control Females vs. Low CP females; Control males vs. Low CP males, and Low CP males vs. Low CP females, identifying, respectively, 26, 19, 12, and 11 DAPs (Differentially Accumulated Proteins). Control males had higher abundance of proteins related to cell differentiation and growth compared to females, highlighting continual muscle accretion in the former and lipogenesis onset in the latter. Control females and males had increased DAPs related to tissue growth and differentiation compared to Low CP animals that had increased lipid accretion. Both sexes reacted similarly to the two diets. Low CP diet led to advanced lipogenesis and decreased muscle accretion pathways. Full article

Previous studies have demonstrated that follicle-stimulating hormone (FSH) plays a critical role in promoting adipogenesis. Surgical castration results in elevated FSH concentrations in pigs, and is accompanied by reduced feed efficiency. This study aimed to investigate the effects of a novel FSH vaccine comprising FSHβ13AA-tandem-ovalbumin conjugate on growth performance and meat quality in barrows. Twenty-four barrows with initial body weight of 32.54 ± 1.90 kg and 12-week age, were randomly assigned to three groups: Placebo-immunized, GnRH-immunized, and FSH-immunized. At three weeks after booster immunization, the FSH-immunized group exhibited significantly improved feed efficiency compared to GnRH-immunized barrows. Compared to the Placebo-immunized group, GnRH and FSH vaccination reduced average backfat thickness by 0.90% and 4.55%, abdominal fat weight by 3.49% and 10.56%, and abdominal fat percentage by 4.09% and 11.95%, respectively. Moreover, the FSH-immunized group showed a significant increase in liver weight relative to the Placebo-immunized group. In addition, compared with the control group, at slaughter FSH vaccination significantly increased muscle pH at 45 min, drip loss at 24 h, and shear force (p < 0.05). These results demonstrate that active immunization against FSH in barrows can enhance feed efficiency and reduce adiposity, as well as influence the meat quality. Full article

The gut microbiota plays a crucial role in maintaining swine health and understanding its stage-specific variations provides a scientific basis for health assessment. This study investigated the structural changes in intestinal microbiota during the development of Sichuan–Tibetan black pigs (n = 15) by collecting fecal samples at three growth stages: the nursery period (1 month), growing period (3 months), and finishing period (10 months). Microbial profiling was performed using 16S rRNA sequencing. Results showed no significant difference in the Shannon index between the nursery and growing periods, while the finishing period exhibited distinct ACE and Chao 1 indices compared to other stages. PCoA and NMDS analyses revealed significant structural divergence in the finishing period microbiota, with greater intra-group variability observed in the nursery and growing periods. At the phylum level, Firmicutes abundance increased progressively with growth, becoming the absolute dominant phylum, whereas Bacteroidota showed a declining trend. These characteristics are particularly prominent during the finishing period. At the family level, Lactobacillaceae abundance increased continuously. Oscillospiraceae remained stable during the early stages but decreased significantly in the finishing period. Genus-level analysis shows that Lactobacillus, especially L. amylovorus and L. reuteri, become dominant bacterial species during the finishing period. A total of 84 differentially abundant core microbiota were identified, with the finishing period containing the highest number. Functional annotation revealed 19 significantly different metabolic pathways across the three stages. The most significant is the enhanced activity of microorganisms during the finishing period in pathogen-related metabolism and exogenous degradation, reflecting their adaptability to complex feed. These findings demonstrate stage-dependent variations in the gut microbiota of Sichuan–Tibetan black pigs, providing valuable references for nutritional regulation and feeding management practices. Full article

Intensive pig production practices may shape cognition and behavior. We evaluated whether repeated regrouping (mixing) and gender (gilts vs. barrows) affect social interactions, fear-related responses, and affective state. A total of 96 growing pigs were separated into two treatments: control—pigs that were mixed once during the growing–finishing period; and social stress—pigs that were mixed thrice during the growing–finishing period. Social and non-social behaviors were directly noted, and four behavioral tests were conducted: open field, novel object, couples, and judgment bias tests. The statistical analysis compared gender and treatment, and p-values ≤ 0.05 were considered significant. Females stayed longer in the test pen entrance area during the novel object test and barrows spent more time at the feeder and defecated more during the couples’ test. With regard to the judgment bias test, females took longer to be considered trained in the discriminatory learning task and presented a “pessimistic judgment” during the ambiguous cue. Our results suggest that gender influences judgment bias in pigs and can influence social and non-social behavior, which may reflect a negative affective state with implications for their welfare and management. Full article

In swine production, it is broadly recognized that ventilation rates and indoor environmental conditions influence pig productivity. However, sparse scientific data are available on the combined effects and potential interactions of these factors in commercial production systems. This study investigated indoor environmental and management factors influencing wean-to-finish pig mortality in a commercial system. Temperature, relative humidity (RH), and carbon dioxide (CO₂) were recorded every 10 min in the front and back of 16 barns across five grow-finish sites in eastern North Carolina for two turns (four barns) or three turns (12 barns) for a total of 44 pig groups. Proportional weekly mortality was modeled using a generalized linear mixed model. Results showed that pigs in environments warmer than the desired room temperature had lower mortality (p < 0.001), suggesting cold stress was more detrimental than heat stress. Elevated RH and CO₂ at the back of the barn were linked to increased mortality (p < 0.001), highlighting air exchange rates as a key indicator. Mortality was greatest in pig groups placed during Spring and lowest in Summer (p < 0.05), and mortality declined as pigs aged (p = 0.0134). Surprisingly, greater barn occupancy correlated with lower mortality (p = 0.0012), potentially related to piglet quality at placement. The predictive power of the model varied with the turn of pigs, with R² averaging 0.24 (ranging from 0.001 to 0.61) and an average RMSE of 0.36% (ranging from 0.17% to 0.77%). Ammonia (NH₃) was recorded at the back of six barns, and concentrations were modeled. Greater NH₃ concentrations were associated with increased pig age, RH, and CO₂, as well as lower deviation from desired room temperature and lower barn occupancy. Collectively, these findings highlight the importance of proper ventilation and management on swine productivity. Full article

This experiment was performed to evaluate the optimum level of net energy (NE) to improve growth performance and nutrient digestibility, and reduce noxious gas emissions in growing–finishing pigs. A total of 150 pigs ([Yorkshire × Landrace] × Duroc) with an initial average body weight (BW) of 32.64 ± 1.49 kg were randomly assigned to one of five treatments for 112 days (16 weeks: growing stage, initial–week 6; finishing stage, 6-finish/week 16). There were five treatment groups with six replicates and five pigs (three males and two females) per pen. The dietary treatment includes CON, a basal diet (NE 2475 kcal/kg), TRT1, basal diet −5.0% NE (2353 kcal/kg), TRT2, basal diet −2.5% NE (2414 kcal/kg), TRT3, basal diet +2.5% NE (2537 kcal/kg), and TRT4, basal diet +5.0% NE (2599 kcal/kg). Through the experiment, increasing NE by +5.0% increased average daily gain and bodyweight, having the highest value (p < 0.05) and a decreased feed conversion ratio (p < 0.05), whereas decreasing NE by −5% decreased average daily gain (p < 0.05) and increased feed conversion ratio (p < 0.05) at week 6 with no effects on nutrient digestibility and noxious gas emission. Hence, integrating the increasing level of net energy (NE) with +5.0% into the pig diet during the growing–finishing phase can be considered the appropriate approach for enhancing both average daily gain and feed efficiency in pigs. A +5% (2599 kcal/kg) increase in NE has the potential to reduce costs by lowering the amount of feed needed while either sustaining or improving growth, as the use of energy-dense ingredients becomes more cost effective. Full article

Estimated population growth and increased demand for food production bring with them the evident need for more efficient and sustainable production systems. Because of this, computer vision plays a fundamental role in the development and application of solutions that help producers with the issues that limit livestock production in Brazil and the world. In addition to being stressful for the producer and the animal, the conventional pig weighing system causes productive losses and can compromise meat quality, being considered a practice that does not value animal welfare. The objective was to develop a computational procedure to predict the live weight of pigs in the growth and finishing phases, through the volume of the animals extracted through the processing of 3D images, as well as to analyze the real and estimated biometric measurements to define the relationships of these with live weight and volume obtained. The study was conducted at Roçadinho farm, in the municipality of Capoeiras, located in the Agreste region of the state of Pernambuco, Brazil. The variables weight and 3D images were obtained using a Kinect^®—V2 camera and biometric measurements of 20 animals in the growth phase and 24 animals in the finishing phase, males and females, from the crossing of Pietrain and Large White, totaling 44 animals. To analyze the images, a program developed in Python (PyCharm Community Edition 2020.1.4) was used, to relate the variables, principal component analyses and regression analyzes were performed. The coefficient of linear determination between weight and volume was 73.3, 74.1, and 97.3% for pigs in the growing, finishing, and global phases, showing that this relationship is positive and satisfactorily expressed the weight of the animals. The relationship between the real and estimated biometric variables had a more expressive coefficient of determination in the global phase, having presented values between 77 and 94%. Full article

In cold-temperature regions, particularly on family farms, threats to livestock health constrain the potential of livestock husbandry. This study aimed to explore the effects of different dietary energy levels, adjusted by oil addition, on gut microbiota and metabolic homeostasis at cold temperatures. Twenty-four healthy pigs were randomly divided into two groups and fed a basal diet (BD) or a basal diet supplemented with oil (OD, with net energy increased by 100 kcal/kg) for 103 days. The cold temperature and humidity were maintained at 14 ± 2 °C and 65 ± 10%, respectively. On day 103 of the experiment, six pigs per group (three barrows and three females) were slaughtered after an overnight fast for sample collection: colon, colonic contents, plasma, and liver. The results showed that dietary oil addition remodeled the gut microbiota, forming a healthier microbial community characterized by a higher abundance of Paludibacter, Parabacteroides, Peptococcaceae, and UCG-008 and a lower abundance of Actinomyces, Turicibacter, Staphylococcus, Megamonas, Fusobacterium, and Achromobacter (p < 0.05). Consistently, dietary oil addition resulted in higher levels of short-chain fatty acids (isobutyrate and isovalerate) and the Claudin-1 protein in the colon (p < 0.05). Plasma analysis showed that dietary oil addition increased energy metabolism and decreased inflammation. This change was characterized by higher levels of glucocorticoid, citrate, corticosterone, taurodeoxycholic acid, and ascorbic acid and lower levels of IL-6 and hypoxanthine (p < 0.05). Transcriptomic and protein expression results in the liver further indicated that dietary oil addition alleviated energy stress and apoptosis by modulating metabolic states at cold temperatures. In conclusion, dietary oil addition improved gut health at cold temperatures in growing–finishing pigs, which was inextricably linked to the remodeling of the gut microbiota and metabolic states. Full article