Tropical animal health and production最新文献

{"title":"Functional assessment of TÜRKVET: animal identification, movement control and veterinary traceability in Türkiye.","authors":"Mahmut Babur","doi":"10.1007/s11250-026-05370-6","DOIUrl":"https://doi.org/10.1007/s11250-026-05370-6","url":null,"abstract":"<p><p>National veterinary information systems are central to animal identification, movement control and official veterinary action, but their operational scope and system boundaries are often described imprecisely. This Short Communication assessed TÜRKVET using current Turkish legislation, official reports dated 24 July 2026 and an authorised examination of the live interface. TÜRKVET operates as a centrally governed national platform across all 81 provinces and integrates holding and actor registration, identifier governance, animal lifecycle records, movement certification and official-control functions. Official reports recorded 1,433,562 active holdings, 18,556,047 cattle and buffalo, and 64,231,597 sheep and goats. Its most comprehensive identification and lifecycle functions apply to cattle, buffalo, sheep and goats; dedicated equid functions are present; camels and other categories are represented through tracking, movement or certification workflows; and poultry and companion-animal identification are managed in complementary external systems. The authorised interface confirmed that identification, movement and official-control functions coexist within one national operational environment. However, public evidence on completeness, timeliness, duplicate resolution, trace-back performance and system availability remains limited. Future evaluation should therefore use explicit performance indicators rather than infer effectiveness from functional breadth or national scale alone.</p>","PeriodicalId":23329,"journal":{"name":"Tropical animal health and production","volume":"58 8","pages":""},"PeriodicalIF":2.0,"publicationDate":"2026-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149115474","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Inclusion of butterfly pea hay in corn silage (with or without cobs) increases nutrient intake and carcass weight in lambs.","authors":"Bruno Augusto de Souza Almeida, Fabio Andrade Teixeira, Timóteo Silva Dos Santos Nunes, Glayciane Costa Gois, Salete Alves de Moraes, Lucas Oliveira Reis, Ery Jonhons Nascimento Ramos, Arquinor Conceição Rodrigues, Daniel Ribeiro Menezes, Elisvaldo José Silva Alencar, Adeilson de Melo Silva, Rafael Torres de Souza Rodrigues, Tiago Bresolin, Mário Adriano Ávila Queiroz","doi":"10.1007/s11250-026-05361-7","DOIUrl":"10.1007/s11250-026-05361-7","url":null,"abstract":"<p><p>This study evaluated the effects of mixed corn silages, with and without commercially viable cobs, combined with butterfly pea (Clitoria ternatea L.) hay on intake, digestibility, water balance, nitrogen balance, and carcass characteristics of lambs. Twenty crossbred intact male lambs (18.0 ± 4.8 kg body weight) were distributed in a randomized complete block design with a 2 × 2 factorial arrangement and five replicates per treatment. Treatments consisted of corn silage with cobs (CSC), CSC plus butterfly pea hay (BH), corn silage without cobs (CSWC), and CSWC plus BH. Butterfly pea hay inclusion increased dry matter intake (P < 0.001), crude protein digestibility (P = 0.006), nitrogen absorption (P = 0.006), hot carcass weight (P = 0.011), and cold carcass weight (P = 0.009). Corn cobs improved starch digestibility (P = 0.015), water balance (P = 0.021), and hot carcass yield (P = 0.021). Average daily gain was not significantly affected, although a numerical increase was observed in lambs fed diets containing BH (P = 0.062). The inclusion of butterfly pea hay improved nutrient utilization and carcass weight, while the maintenance of corn cobs enhanced starch utilization and water balance in lambs fed corn silage-based diets.</p>","PeriodicalId":23329,"journal":{"name":"Tropical animal health and production","volume":"58 8","pages":""},"PeriodicalIF":2.0,"publicationDate":"2026-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13623800/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149082255","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of ovarian dynamics and circulating steroid hormones on OPU-IVEP outcomes in Holstein heifers.","authors":"Omer Faruk Yesilkaya, Muhammed Furkan Ciftci, Maide Gölbasi, Ayse Sari, Mustafa Bodu, Sakine Ülküm Ci̇zmeci","doi":"10.1007/s11250-026-05373-3","DOIUrl":"10.1007/s11250-026-05373-3","url":null,"abstract":"<p><p>In bovine in vitro embryo production (IVEP), optimizing oocyte quality and yield per donor serves as the cornerstone for improving blastocyst development and field efficiency. This study evaluated the impact of naturally occurring ovarian structures on follicular dynamics, oocyte quality, and embryo development during random-day ovum pick-up (OPU) in Holstein heifers (n = 78). Donors were divided into three groups based on ovarian patterns: Group I (corpus luteum [CL]; n = 43), Group II (only antral follicles [AF]; n = 20), or Group III (CL + dominant follicle [CL + DF]; n = 15). Follicles (3-8 mm) were aspirated, and serum progesterone (P4) and estradiol (E2) levels were measured. Group I had a significantly higher usable (A + B+C) oocyte count (7 vs. 3) and total oocyte count (10 vs. 5) than Group III (P < 0.05). The mid-sized follicle pool was lower in Group III than in Group II (11 vs. 13; P < 0.05). Mature oocytes, cleaved zygotes, and blastocyst counts were significantly lower in Group III than in Groups I and II (P < 0.05). Group I achieved a higher cleavage rate than Group III (77.60 vs. 62.06; P < 0.05). Crucially, the blastocyst formation rate was significantly higher in Groups I (49.59%) and II (45.45%) than in Group III (22.20%; P < 0.05). On the OPU day, donors with serum P4 > 1 ng/mL exhibited a higher yield of B-quality oocytes than did those with P4 < 1 ng/mL (1.5 vs. 1.0; P < 0.05). In conclusion, a dominant follicle during random-day OPU is closely associated with a lower antral follicle pool, compromised oocyte quality, and reduced embryo development. Consequently, avoiding active follicular dominance during donor management might represent a supportive strategy to optimize IVEP efficiency under commercial field conditions.</p>","PeriodicalId":23329,"journal":{"name":"Tropical animal health and production","volume":"58 8","pages":""},"PeriodicalIF":2.0,"publicationDate":"2026-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149075965","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lemongrass oil supplementation: buffalo-derived in vitro screening of ruminal fermentation and in vivo evaluation in growing beetal goats.","authors":"Pratik Sudan, Amit Sharma, J S Hundal, Mandeep Singla, R S Grewal","doi":"10.1007/s11250-026-05364-4","DOIUrl":"10.1007/s11250-026-05364-4","url":null,"abstract":"<p><p>The application of essential oils in ruminant diets presents challenges due to variability in their effects based on dose, diet composition and animal physiology. This study aimed to screen different supplementation levels of lemongrass oil (LGO) through in vitro evaluation for subsequent in vivo assessment of its effects on growth, nutrient digestibility and antioxidant status in Beetal goat kids. The in vitro trial used berseem fodder and concentrate mixture (60:40) incubated with LGO at 0, 0.5, 1.0, 1.5, and 2.0% of dry matter (DM) for 24 h. It was observed that LGO supplementation resulted in a quadratic effect on gas production, in vitro organic matter digestibility and metabolizable energy with values increasing up to 1.0% LGO and declining at higher inclusion levels. In contrast, in vitro dry matter digestibility remained unaffected, while partitioning factor and microbial biomass production tended to decrease with LGO supplementation. LGO supplementation shifted rumen fermentation towards greater propionate and lower acetate production. In the in vivo trial, eighteen goat kids (90 ± 5 days old; 6.29 ± 0.39 kg overall mean initial body weight) were fed either a basal diet or a basal diet supplemented with 1% LGO for 90 days. No significant differences were observed in body weight gain, dry matter intake, digestibility or blood biochemistry. However, LGO supplementation tended to improve erythrocytic catalase and superoxide dismutase activities, with a transient increase in skin-fold thickness up to 48 h post-injection. Overall, the observed responses may have been influenced by small sample size, lower weaning body weight and in vitro-in vivo microbial differences, warranting further study.</p>","PeriodicalId":23329,"journal":{"name":"Tropical animal health and production","volume":"58 8","pages":""},"PeriodicalIF":2.0,"publicationDate":"2026-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149076005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Melatonin and betaine supplementation mitigate oxidative and endocrine dysregulation to restore ovarian activity in summer anestrus buffaloes.","authors":"Abhijeet Fernandes, Chirag Pruthi, M Akram, Chinmayee Sahu, Nishant Kumar, T K Mohanty, Rubina K Baithalu","doi":"10.1007/s11250-026-05355-5","DOIUrl":"10.1007/s11250-026-05355-5","url":null,"abstract":"<p><p>Buffaloes are polyestrous but display a marked seasonal decline in reproductive efficiency during summer, primarily due to longer photoperiod, heat stress, altered endocrine profiles, and heightened oxidative stress, resulting in a high incidence of summer anestrus (36.6-59.6%). This study evaluated the effects of melatonin and betaine supplementation on ovarian function, endocrine dynamics, and oxidative status in buffaloes during the low-breeding season. Anestrus buffaloes (n = 22) with a history of up to 90 days postpartum anestrus were monitored for 21 days and allocated into three groups: Control (n = 7), melatonin-treated (T1; n = 7; sustained-release melatonin @ 18 mg/50 kg BW, S/C, once), and betaine-treated (T2; n = 8; 25 g/day orally for 30 days). Blood sampling and transrectal ultrasonography were performed at 10-day intervals to assess follicular activity, endocrine responses, and oxidative stress markers. Melatonin and betaine treatments significantly alleviated summer-induced stress, as evidenced by reduced prolactin and nitric oxide (NO) levels (P < 0.05) and by increased total antioxidant capacity (TAC) compared with controls. Melatonin administration caused a sustained increase in circulating melatonin concentrations and improved LH-dependent ovarian activity. Although dominant follicles developed in all animals, untreated controls failed to ovulate and exhibited follicular atresia, hyperprolactinemia, elevated NO, and reduced TAC. In contrast, treated groups exhibited increased TAC, reduced NO and prolactin from day 20 onward, and elevated progesterone following estrus induction, confirming ovulation. Estrus induction and conception rates were highest in the melatonin group (57.14% and 66.6%), followed by betaine (25% and 50%), whereas no conceptions occurred in controls. Overall, melatonin and betaine effectively mitigated oxidative and endocrine disruptions, enhanced follicular function, and facilitated reactivation of the hypothalamic-pituitary-ovarian axis, thereby improving estrus induction and ovulatory responses in buffaloes during the low-breeding summer season.</p>","PeriodicalId":23329,"journal":{"name":"Tropical animal health and production","volume":"58 8","pages":""},"PeriodicalIF":2.0,"publicationDate":"2026-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149075360","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hair cortisol as a biomarker of chronic stress in periparturient dairy cattle: associations with health status, lactation, and metabolic profiles.","authors":"Nusrat Jahan Momy, Md Naim Uddin Nipu, Md Shohel Al Faruk","doi":"10.1007/s11250-026-05371-5","DOIUrl":"10.1007/s11250-026-05371-5","url":null,"abstract":"<p><p>Dairy cows experience long-term stress during the pre- and postpartum period, as during this period they face extreme challenges related to their health, productivity and overall welfare. Recently, hair cortisol has gained attention as one of the most promising and non-invasive biomarkers for evaluating stress. However, the exact mechanism of its deposition in the hair remains unknown. This review combines the utility of hair cortisol as a tool for evaluating chronic stress and its effect on health status, lactation, parity, body condition score (BCS), and metabolic parameters, specifically glucose, β-hydroxybutyrate (BHBA), and non-esterified fatty acids in dairy cows. Emphasis is given to the transition period around parturition, where hormonal fluctuation, negative energy balance, and immunosuppression increase the animal's susceptibility to stress. Methodologically, tail hair exhibits a higher cortisol concentration than other regions due to a faster growth rate, making it an ideal site for maintaining a proper sampling interval during the transition period. Furthermore, regrown hair contains higher cortisol levels than native hair during parturition. In addition, hair cortisol level significantly elevated during peak lactation in multiparous cows and in cows with oversized or twin calves. Notably, newborn calves have higher cortisol than their dam during birth. Cows diagnosed with a disease condition display higher cortisol levels than healthy cows during the postpartum period. During the transition period, Glucose was found to be positively correlated with hair cortisol level, whereas β-hydroxybutyrate (BHBA) was negatively correlated with hair cortisol in multiparous cows. Ultimately, evaluating hair cortisol concentration alongside associated production and metabolic factors during the periparturient period can provide a proper framework for improving and monitoring dairy cattle welfare. However, further research is required on hair cortisol concentration and its connection with various stressors of the transition period, sampling and analytical methods, and a standardized reference range so that it can have practical use at the farm level.</p>","PeriodicalId":23329,"journal":{"name":"Tropical animal health and production","volume":"58 8","pages":""},"PeriodicalIF":2.0,"publicationDate":"2026-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149075996","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Animal reproduction in the tropics and subtropics: matching innovation with resilience and reality.","authors":"Carolina P Bianchi, Fernando Sánchez Dávila, Mounir Adnane, Sanjay Choudhary, Rodolfo Ungerfeld","doi":"10.1007/s11250-026-05369-z","DOIUrl":"10.1007/s11250-026-05369-z","url":null,"abstract":"<p><p>Climate variability poses a major challenge to reproductive performance in tropical and subtropical livestock systems, where prolonged droughts, irregular rainfall, heat stress, and abrupt nutritional restrictions can disrupt reproductive function. Thus, future research should focus on integrated, context-specific strategies that combine reproductive technologies with adapted genetics, management, nutrition, disease prevention, and accessible reproductive health services. Particular attention should be given to locally adapted breeds and populations, whose reproductive resilience conventional productivity metrics may not adequately capture. Genetic improvement should therefore be evaluated by animals' ability to maintain reproductive function and productivity under the specific constraints of their production environments. Research should also prioritize strategies that tolerate climatic and nutritional disruptions rather than relying on predictable seasonal patterns. Importantly, research should be conducted in collaboration with producers and communities to ensure practical relevance, adoption, and sustainability. The future of animal reproduction in tropical and subtropical regions should therefore focus on identifying and implementing species- and context-specific combinations of technologies and practices that maintain reproductive function under increasingly variable and unpredictable environments.</p>","PeriodicalId":23329,"journal":{"name":"Tropical animal health and production","volume":"58 8","pages":""},"PeriodicalIF":2.0,"publicationDate":"2026-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149075959","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Avoidance distance in dairy cattle as a behavioural indicator of fear responses: the confounding role of clinical health status in two Algerian dairy farms.","authors":"Nassima Bouhroum","doi":"10.1007/s11250-026-05352-8","DOIUrl":"10.1007/s11250-026-05352-8","url":null,"abstract":"<p><p>Fear responses toward humans are a central determinant of dairy cattle welfare and productivity. Avoidance distance (AD), the minimum approach distance tolerated by a stationary animal at the feeding rack, is a behavioural indicator of human-animal relationship (HAR) quality used in the Welfare Quality^® protocol. This preliminary, hypothesis-generating study examined predictors of AD ≥ 50 cm in 72 dairy bovines (Montbéliarde and Holstein Friesian) from two commercial farms in the wilaya of Aïn Defla, Algeria (Sidi Omer, n = 36; El-Hamoul, n = 36), using univariate chi-square/Fisher's exact tests and a generalised estimating equations (GEE) logistic regression with an exchangeable working correlation structure. Mastitis was by far the strongest correlate of avoidance: all 15 affected animals at Sidi Omer were avoidant (Fisher's exact p < 0.0001), consistent with pain-induced hypervigilance. Age was significant at Sidi Omer (χ² = 17.05; p = 0.0002) but not at El-Hamoul, where tolerance was near-universal. Sex was not significant at Sidi Omer alone (p = 0.149), and the nominally significant combined-sample result (χ² = 7.14; p = 0.0075) did not survive Bonferroni correction. A large between-farm difference was observed (χ² = 24.27; p < 0.0001): 97.2% of El-Hamoul animals were tolerant versus 44.4% at Sidi Omer. Farm membership was almost completely confounded with health status, so this contrast cannot be attributed to stockperson behaviour specifically. These findings support recording health status at AD testing and generate hypotheses on pain-related hypervigilance and farm-level management warranting confirmation in larger, multi-farm studies with direct assessment of stockperson behaviour.</p>","PeriodicalId":23329,"journal":{"name":"Tropical animal health and production","volume":"58 8","pages":""},"PeriodicalIF":2.0,"publicationDate":"2026-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149075991","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Growth modeling of Lori sheep using artificial neural networks and nonlinear regression.","authors":"Mohammad Reza Bahreini Behzadi, Samira Hasanalizadeh","doi":"10.1007/s11250-026-05366-2","DOIUrl":"10.1007/s11250-026-05366-2","url":null,"abstract":"<p><p>This study evaluates growth performance in Lori sheep using two modeling approaches: traditional nonlinear regression and artificial neural networks (ANNs). Body weight data were collected from 210 lambs at monthly intervals from birth to six months of age. Six nonlinear growth models including Brody, von Bertalanffy, Gompertz, Logistic, Verhulst, and negative exponential were compared with two neural network architectures: multilayer perceptron (MLP) and radial basis function (RBF). Model performance was assessed using the coefficient of determination (R²), root mean square error (RMSE), Akaike information criterion (AIC), and correlation between observed and predicted values. Among the nonlinear models, the Brody function provided the best fit, accurately capturing sigmoidal growth behavior and offering biologically interpretable parameters such as asymptotic mature weight (A) and maturity rate (k). Males exhibited higher growth rates and asymptotic weights than females, indicating sexual dimorphism. Growth velocity peaked early and declined with age, consistent with physiological development patterns. Artificial neural networks achieved high predictive accuracy, with correlation coefficients exceeding 0.996. Although these models effectively captured nonlinear growth dynamics, traditional models remain preferable in farm settings due to their interpretability and ease of use. The Brody model also proved reliable for predicting live weight at later stages using early body weight data, supporting improved decisions in nutrition planning, health monitoring, and breeding selection. For applications focused on growth curve monitoring, neural networks offer a practical alternative capable of automating evaluations and delivering accurate insights without requiring statistical expertise. Integrating biologically grounded models with machine learning techniques may enhance predictive accuracy and livestock management. Future research should explore hybrid modeling frameworks and incorporate environmental and nutritional variables to further optimize growth prediction.</p>","PeriodicalId":23329,"journal":{"name":"Tropical animal health and production","volume":"58 8","pages":""},"PeriodicalIF":2.0,"publicationDate":"2026-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149076052","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genomic evaluation of productive-life indicators associated with longevity in Girolando cattle under tropical dairy conditions.","authors":"Darlene Dos Santos Daltro, Elisandra Lurdes Kern, Jaime Araújo Cobuci, Renata Negri, Sabrina Kluska, Pamela Itajara Otto, Marco Antonio Machado, João Cláudio do Carmo Panetto, Marta Fonseca Martins, Edivaldo Ferreira Júnior, Fabrício Pilonetto, Marcos Vinicius Gualberto Barbosa da Silva","doi":"10.1007/s11250-026-05336-8","DOIUrl":"10.1007/s11250-026-05336-8","url":null,"abstract":"<p><p>This study aimed to estimate (co)variance components, heritability, and genetic associations among productive-life indicators related to longevity, productive traits, and fertility traits in Girolando cattle and to explore associated genomic regions. Four productive-life indicators were evaluated: total milk production across all lactations (L1), number of lactations initiated (L2), total days in milk across all lactations (L3), and number of complete lactations (L4). Productive traits comprised 305-d milk yield (MY305) and lactation length (LL), whereas fertility traits comprised age at first calving (AFC), calving interval (CI), and days open (DO). Variance components were estimated under linear animal models using the single-step genomic relationship matrix, using AIREMLF90 from the BLUPF90 suite. Heritability estimates ranged from 0.06 to 0.31 for productive-life indicators, 0.06 to 0.14 for productive traits, and 0.03 to 0.06 for fertility traits. Genetic correlations of productive-life indicators ranged from 0.02 to 0.31 with productive traits and from - 0.03 to 0.13 with fertility traits, indicating stronger associations with productive traits. An exploratory single-step genome-wide association study identified candidate regions for L1 and L3, whereas no SNP met the adopted significance criteria for L4. Because culling and death dates were unavailable, L1, L3, and L4 represent proxies of productive life rather than direct measures of functional longevity; consequently, related inferences remain preliminary. Overall, environmental and management effects substantially influence these indicators. Selection for improved productive life may therefore benefit from indexes combining productive-life indicators with routinely recorded productive and fertility traits.</p>","PeriodicalId":23329,"journal":{"name":"Tropical animal health and production","volume":"58 8","pages":""},"PeriodicalIF":2.0,"publicationDate":"2026-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149075977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}