Tropical animal health and production最新文献

{"title":"Critical thresholds of BHBA and NEFA for subclinical ketosis and its prevalence prediction in Indian mithun (Bos frontalis) cows demonstrated by ROC analyses.","authors":"Vivek Joshi, J K Chamuah, Vikram R, Lipenthung Y Ezung, Kobu Khate","doi":"10.1007/s11250-025-04394-8","DOIUrl":"https://doi.org/10.1007/s11250-025-04394-8","url":null,"abstract":"<p><p>Indian mithun (Bos frontalis), a rare ruminant species, is exclusively found in northeastern hill region of India and reared under semi-intensive system. Subclinical ketosis (SCK) is caused by an imbalance between energy supply and the needs of cows during lactation. To date, SCK prevalence is not known in mithun and biomarkers for its prediction have not been standardized. The study aimed to establish critical thresholds for serum beta-hydroxybutyrate (BHBA) and non-esterified fatty acids (NEFA) for diagnosis and prevalence prediction of SCK in early-lactation mithun cows. Thirty apparently healthy multiparous (second to sixth lactation) mithun cows (average body weight of 342 ± 45.5 kg) with confirmed pregnancy were selected from two semi-intensive farms. None of the early-lactation mithuns with average milk yield of 1.2 kg/day exhibited signs of any metabolic disease during monitoring period (1, 2, 4 weeks post-partum). Using receiver operating characteristic (ROC) curve analyses, the optimal cut-off point was selected to be ≥ 1.10 mmol/L for BHBA (80% sensitivity, 80% specificity, AUC = 0.9) and ≥ 0.26 mmol/L for NEFA (88.20% sensitivity, 72% specificity, AUC = 0.9). In accordance with cut-off points, mithuns were classified as having SCK and healthy. At 1, 2 and 4 weeks post-partum, 55%, 82% and 64% of the mithun cows had SCK, respectively. There was a significant positive correlation between BHBA and NEFA concentrations (r = 0.78). A rise in serum NEFA and SGOT activity with a concomitant decline in total cholesterol and triglycerides may predict the risk of liver dysfunction associated with SCK. This study is of value in addressing future research on the development of fresh mithun cow programs to prevent SCK and associated liver dysfunction in first 4 weeks post-partum.</p>","PeriodicalId":23329,"journal":{"name":"Tropical animal health and production","volume":"57 3","pages":"130"},"PeriodicalIF":1.7,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143658735","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":"Effect of additional intracervical prostaglandin administration on cervical dilatation during incomplete cervical dilatation in uterine torsion corrected buffaloes.","authors":"Ankit Ahuja, Mrigank Honparkhe, Ajeet Kumar, Pankaj Sood","doi":"10.1007/s11250-025-04379-7","DOIUrl":"https://doi.org/10.1007/s11250-025-04379-7","url":null,"abstract":"<p><p>Present study investigated the efficacy of additional intracervical (IC) prostaglandin (PG; cloprostenol sodium-500 μg) administration in buffaloes experiencing incomplete cervical dilatation (ICD) after uterine torsion correction. Twenty-two buffaloes in first stage of labor with soft to partially lobulated external-os post-torsion correction, with mean age: 7.0 ± 0.54 years, parity: 3.6 ± 0.47 (no.) and gestation length: 311.5 ± 1.12 days, were randomly divided into two groups viz. IC-group (n = 14) and intramuscular (IM) group (n = 8). In addition to conventional induction protocol, IC-group received an additional IC injection of PG at the start of experiment, whereas IM-group received an extra IM dose of PG after either 24 h or when no cervical dilatation progress was noticed. Surprisingly, mean cervical dilatation in terms of external-os and internal-os diameter after 12 h was 2.05 times and 3.38 times, and after 24 h, 2.03 times and 3.33 times higher (P < 0.001) in IC-group as compared to IM-group. After 36 h, calving occurred (P < 0.001) in 100.0 percent buffaloes of IC-group whereas in IM-group it occurred in 25.0 percent buffaloes. Rates of cervical dilatation, both in terms of external-os and internal-os diameter, after 12 and 24 h post-treatment, were also higher (P < 0.001) in IC-group in comparison to IM-group. Predictive model (P < 0.001) demonstrated that for each hour of progression, cervical dilatation at external-os and internal-os was increased by 0.285 and 0.301 units (cm) in IC-group, and 0.150 and 0.131 units in IM-group, respectively. Hence it can be concluded that additional intracervical prostaglandin in buffaloes affected with ICD post-torsion correction accentuates cervical dilatation.</p>","PeriodicalId":23329,"journal":{"name":"Tropical animal health and production","volume":"57 3","pages":"123"},"PeriodicalIF":1.7,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143650207","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":"Retinol and cholecalciferol affect buserelin-induced estrous in anestrous mares.","authors":"Syed S U H Bukhari, Sundas Urooj","doi":"10.1007/s11250-025-04369-9","DOIUrl":"10.1007/s11250-025-04369-9","url":null,"abstract":"<p><p>In winter anestrous, prolonged melatonin secretion inhibits gonadotropin-releasing hormone (GnRH). However, synthetic GnRH analogues such as buserelin can stimulate follicular development. We aimed to investigate clinical relationship between retinol, cholecalciferol, and buserelin for inducing estrous in anestrous mares (Equus caballus). We used a total of twenty-one anestrous mares, randomly divided into three groups of seven animals. Group A received retinol, cholecalciferol, and buserelin; group B received buserelin; and group C was control. Groups A, B, and C had 71.42% (n = 5; 95% CI: 26.30%-96.56%), 28.57% (n = 2; 95% CI: 16.56%-73.70%), and 0% mares in estrous, respectively. A significantly greater number of group A mares exhibited estrous (P = 0.005) and higher ovarian follicular size (P = 0.001) compared to group C. Serum estrogen was significantly higher in group A compared to Group B (P = 0.03) and C mares (P = 0.001). In multiple correspondence analysis (MCA) factor map, treatment with retinol, cholecalciferol, and buserelin was clustered with estrous mares having serum estrogen levels > 40 pg/ml and follicular size > 30 mm. The variance explained by the first two dimensions of MCA was 87.83%. Supplementing with retinol and cholecalciferol improved the rate of buserelin-induced estrous in anestrous mares. Further research is necessary to determine underlying mechanisms.</p>","PeriodicalId":23329,"journal":{"name":"Tropical animal health and production","volume":"57 3","pages":"124"},"PeriodicalIF":1.7,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11913942/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143650421","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":"Ruminal fermentation kinetics and in vitro gas production of yeast-enriched agro-industrial by-products as alternatives to soybean meal in ruminant diets.","authors":"Arlan Araujo Rodrigues, Sara Silva Reis, Igor Machado Ferreira, André Luiz Rodrigues Magalhães, Fleming Sena Campos, Juliana Silva de Oliveira, Edson Mauro Santos, Daniele de Jesus Ferreira, Hilario Cuquetto Mantovani, Anderson de Moura Zanine, Severino Gonzaga Neto","doi":"10.1007/s11250-025-04371-1","DOIUrl":"https://doi.org/10.1007/s11250-025-04371-1","url":null,"abstract":"<p><p>This study aimed to evaluate the impact of replacing soybean meal with yeast-enriched acerola, pineapple, and orange agro-industrial residues on ruminal fermentation kinetics and in vitro gas production. Using a 3 × 5 factorial design in a completely randomized design with three replicates, the study tested three agro-industrial residues (acerola, orange, and pineapple) at five replacement levels (0, 25, 50, 75, and 100% on a dry matter basis). Cumulative gas production was measured over time and analyzed using the Gompertz model. Linear and quadratic polynomial contrasts were used to examine the responses of feeds to increasing addition levels of the residues. The inclusion of pineapple residue linearly increased total gas production (P = 0.038), while acerola residue resulted in a linear decrease (P = 0.004) and orange residue had no significant effect on gas production (P > 0.05). Orange residue linearly reduced the lag phase (P = 0.048), acerola showed a quadratic effect with an increase of up to 75% inclusion, followed by a decrease (P = 0.009), while pineapple had no significant effect on the lag phase (P > 0.05). Digestibility of organic matter increased with the inclusion of orange and pineapple residues (P < 0.05) but decreased linearly with higher acerola inclusion (P = 0.008). Overall, replacing soybean meal with yeast-enriched residues affects ruminal fermentation, gas production, and digestibility of organic matter. Pineapple and orange residues are effective substitutes, capable of replacing up to 100% of the soybean meal in the concentrate. However, the inclusion of acerola residue was not efficient, resulting in lower responses in the evaluated parameters compared to the control treatment.</p>","PeriodicalId":23329,"journal":{"name":"Tropical animal health and production","volume":"57 3","pages":"125"},"PeriodicalIF":1.7,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143650604","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":"Random regression in comparison with finite-dimensional models for estimation of genetic parameters for growth traits in goats.","authors":"Zeleke Tesema, Belay Derbie, Tesfaye Getachew, Selam Meseret, Solomon Gizaw","doi":"10.1007/s11250-025-04366-y","DOIUrl":"https://doi.org/10.1007/s11250-025-04366-y","url":null,"abstract":"<p><p>The application of the random regression model in comparison with finite-dimensional models (univariate and multivariate animal models) for genetic parameter estimation of growth traits in goats was evaluated in this study. A total of 2888 body weight records from 875 animals, recorded from birth to yearling age were used. All models included direct additive genetic and maternal genetic effects as a random effect in addition to fixed effects. Random regression model (RRM) was fitted with different orders (1st - 3rd) of Legendre polynomials and accounted for both homogeneous and heterogeneous residual variance. The best-fitting RRM had a polynomial of three orders for both random effects. The direct heritability estimate obtained via RRM was moderate to high, while it varied from 0.00 ± 0.08 to 0.36 ± 0.10 in finite dimensional models. A lower standard error of heritability and genetic correlation estimates was observed with RRM compared to multivariate (MUV) and univariate (UNI) analysis. Likewise, high accuracy and reliability of breeding value estimates are obtained via RRM, whereas the accuracy for MUV and UNI animal models were moderate and low to moderate, respectively. Based on standard errors, accuracy, and reliability of estimates, RRM seems versatile for genetic evaluation of growth traits of goats. However, the MUV animal model is the best-fitting model, according to the information criteria values. Thus, for small and less frequently measured data set, multivariate animal model seems good. Further studies with large and frequently measured body weight data sets may help ensure random regression's applicability and differentiate it from finite-dimensional models.</p>","PeriodicalId":23329,"journal":{"name":"Tropical animal health and production","volume":"57 2","pages":"121"},"PeriodicalIF":1.7,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143634832","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 yeast and saccharides based-product to replace monensin in the diet of confined steers: performance, rumen environment, metabolism, animal health, and meat quality.","authors":"Charles Marcon, Luisa Nora, Guilherme L Deolindo, Mateus H Signor, Andrei L R Brunetto, Pedro D B Benedeti, Diego D C Cucco, Luiz E Lobo, Roger Wagner, Bruna Klein, Miklos M Bajay, Bianca F Bissacotti, Marcylene V Silveira, Eduardo M Paula, Verônica Lisboa Santos, Juliana Bueno da Silva, Aleksandro S da Silva","doi":"10.1007/s11250-025-04353-3","DOIUrl":"https://doi.org/10.1007/s11250-025-04353-3","url":null,"abstract":"<p><p>The present study aimed to evaluate a blend of yeast and saccharides based-product fed via diet to feedlot cattle on performance, health, meat quality, and rumen metabolism when compared to monensin. Twenty-four non-castrated crossbred male steers (Charolais x Nellore) were divided into control (n = 12), receiving the basal diet with monensin (215 mg/animal/day) and treatment (n = 12) receiving the basal diet with the blend of yeast and saccharides based-product (17.2 g/animal/day). Animals were weighed on days 1, 20, and 113, and on days 20, 70, and 113, blood and rumen fluid were collected, which was also used to determine the genera of bacteria present in the rumen and to quantify protozoa. Total feces were collected to determine apparent total tract digestibility from days 108 to 112 of the experiment. There was no treatment effect for weight gain, feed intake, or feed efficiency. There was a gain in the loin eye area in the control group (P = 0.05) and greater subcutaneous fat thickness in the loin and rump cap control group (P = 0.01). In the ruminal fluid, there was higher protozoa count in the treatment group on day 113 (P = 0.03) and a higher proportion of propionic acid in the treatment group on day 70 (P = 0.03). Total short-chain fatty acids were lower in steers in the treatment group. There was no treatment effect on the ruminal microbiota. There were lower counts of lymphocytes and granulocytes in the blood of steer in the treatment group (P < 0,05). A significant increase in the concentrations of immunoglobin A (IgA) and others heavy-chain immunoglobulins (IgM, IgG, IgM and IgE) were observed in the treatment group. There was an effect of treatment on glutathione S-transferase (GST) activity on days 70 and 113 (P = 0.02). Likewise, high GST activity in the liver was identified in the treatment group (P = 0.01). For fatty acid profile in meat, oleic acid presented higher proportion in the treatment group (P = 0.04), in contrast to docis-5,8,11,14,17-eicosapentaenoic acid, which was lower in the same group (P = 0.05). It is concluded that the blend of yeast and saccharides based-product played a role similar to monensin's in productive performance, demonstrating a potential to substitute monensin. Furthermore, the inclusion of yeast and saccharides in the diet stimulated the humoral immune response and antioxidant action without affecting meat quality.</p>","PeriodicalId":23329,"journal":{"name":"Tropical animal health and production","volume":"57 2","pages":"120"},"PeriodicalIF":1.7,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143634830","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":"Effects of breed, diet and sex on expression of growth-related genes in Nigerian goats.","authors":"Iliya Mallam, Abdulmojeed Yakubu, Maikano Mohammed Ari, Ibrahim Suleiman Musa, Neyu Patrick Achi","doi":"10.1007/s11250-025-04380-0","DOIUrl":"https://doi.org/10.1007/s11250-025-04380-0","url":null,"abstract":"<p><p>This experiment was conducted to study the effects of breed, diet and sex on expression of growth-related genes in Nigerian goats. A total of 36 weaner goats of two breeds (West African dwarf, n = 18; 9 males + 9 females) and Red Sokoto goats, n = 18; 9 males + 9 females) of about 3-4 months of age were used for the experiment. A 2 × 3 × 2 factorial experiment comprising 2 breeds, 3 diets groups and 2 sexes in a Completely Randomized Design was used. The data for gene expression and their interaction effects were all analysed using Statistix Analytical software, file version 8.0. Results showed that breed, diet and breed × diet interaction had significant (P < 0.05) effect on IGF-1 tissue expression. Sex had significant (P < 0.05) effect on myostatin tissue expression. Breed × diet interaction had no significant (P > 0.05) effect on MSTN expression in the tissue of goats. The results for breed × sex interaction had no significant (P > 0.05) effect on the level of IGF-1 expression in the tissue of goats but had significant (P < 0.05) effect on myostatin gene. Red Sokoto breed is recommended over West African dwarf breed while RS × 50%DS + 50%GH is recommended for IGF-1 expression. There is need for further research to fully understand the IGF-1 and MSTN gene expression levels in various tissues and organs of goats at different stages of growth.</p>","PeriodicalId":23329,"journal":{"name":"Tropical animal health and production","volume":"57 2","pages":"122"},"PeriodicalIF":1.7,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143634827","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":"Ultrasound imaging of the spleen, liver, and kidneys in healthy hair sheep: a pilot study.","authors":"Tatiane Vitor da Silva, Rafael do Prado Freitas, Claudilane Rodrigues Carvalho, Beatriz Souza Costa, Marcella Silva Rosendo Dos Santos, Delia Maria Lacasta Lozano, Pablo Quilez Lozano, Jobson Filipe de Paula Cajueiro, Mário Felipe Alvarez Balaro","doi":"10.1007/s11250-025-04375-x","DOIUrl":"https://doi.org/10.1007/s11250-025-04375-x","url":null,"abstract":"<p><p>This study aimed to describe the ultrasonographic appearance of the liver, spleen, and kidneys in 35 healthy Santa Inês breed sheep. The spleen was located caudal to the last rib and extended to the 8th intercostal space (ICS), while the splenic vein was predominantly visible between the 11th and 10th ICS, located between the 12th and 9th ICS. The liver was visualized from the 12th to the 7th ICS, with the portal vein exhibiting a mean diameter of 15.4 ± 2.0 mm, a rounded shape, and echogenic walls. The caudal vena cava appeared in triangular, elliptical, or round shapes, with a mean diameter of 12.13 ± 3.0 mm. The gallbladder (GB) displayed various shapes, with anechoic to hypoechoic content, and wall measurements of 29.2 ± 11.8 mm in length, 237.4 ± 147.7 mm² in area, and 10.3 ± 4.1 mm in height. The kidneys were examined in both the craniodorsal and caudodorsal quadrants, with the right kidney observed at the 12th ICS and the left kidney typically in the right caudodorsal quadrant. The mean kidney volume was 42.8 ± 9.8 cm³ for the right kidney and 44.2 ± 10.6 cm³ for the left kidney, with average cortical and medullary diameters of 0.74 ± 0.1 cm and 0.6 ± 0.15 cm, respectively. The biometric measurements for the ureter, renal pelvis, and hilum were as follows: right kidney (0.13 ± 0.02, 0.16 ± 0.05, 0.7 ± 0.1 mm) and left kidney (0.14 ± 0.02, 0.15 ± 0.05, 0.6 ± 0.1 mm). These findings provide valuable reference values for ultrasonographic examination of abdominal organs in Santa Inês sheep, which may assist in the diagnosis and monitoring of pathologies in these animals. The methodology used showed a complete scan of the liver, spleen and kidney and proved to be a reliable technique for application in clinical routine as it allows the evaluation of the extent of the entire organ, avoiding incomplete or mistaken diagnoses.</p>","PeriodicalId":23329,"journal":{"name":"Tropical animal health and production","volume":"57 2","pages":"119"},"PeriodicalIF":1.7,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143630842","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":"Staphylococcus borealis causing subclinical mastitis in dromedary camels.","authors":"Rakesh Ranjan, Aruna Kuniyal, Amita Ranjan, Meetpal Singh, Basanti Jyotsana, R K Sawal, Khulape Sagar Ashok","doi":"10.1007/s11250-025-04372-0","DOIUrl":"https://doi.org/10.1007/s11250-025-04372-0","url":null,"abstract":"<p><p>Recent studies revealed increasing incidence of udder infections caused by Coagulase Negative Staphylococci (CNS) in dairy cattle, though studies in dromedary camel are meagre. The present report describes sub-clinical mastitis in two dromedary camels caused by Staphylococcus borealis, a recently recognized udder pathogen in cattle. The bacterium was identified on the basis of morphological and biochemical characteristics, MALDI-TOF MS analysis, 16s rRNA sequencing and BLAST. Phylogenetic analysis was also performed. The isolate was submitted to National Centre for Veterinary Type Cultures, Hisar, India. The bacterium showed varying biochemical reactions as compared to bovine and human isolates. The bacterium has high antibiotic sensitivity perhaps due to less use of antibiotics in treatment of different diseases in camel. To our knowledge, this is the first report indicating Staphylococcus borealis as a cause of subclinical mastitis in dromedary camel.</p>","PeriodicalId":23329,"journal":{"name":"Tropical animal health and production","volume":"57 2","pages":"117"},"PeriodicalIF":1.7,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143630836","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":"Evaluation of empirical and mechanistic models and sampling intervals to model the lactation curves of F1 dairy sheep.","authors":"Lilian Guevara, Nicolas Lopez-Villalobos, Geoffrey Ernest Pollott, Benito Albarrán-Portillo, Alberto Magno Fernandes, Jesús Armando Salinas-Martínez, Juan Carlos Angeles-Hernandez","doi":"10.1007/s11250-025-04365-z","DOIUrl":"10.1007/s11250-025-04365-z","url":null,"abstract":"<p><p>Recently Latin American countries have developed a dairy sheep industry with an increasing number of specialized dairy-sheep flocks. The objective of this study was to evaluate the goodness of fit of empirical and mechanistic models and sampling interval to model the lactation curve of F1 dairy sheep with different shape of lactation curves in an intensively managed flock of the central highlands of Mexico. A total of 4,494 weekly (7D) test day records (TDR) from 156 lactations were analyzed. Three datasets were generated from the original 7D data set, setting TDR at different sampling intervals: 14 (14D), 21 (21D) and 28 (28D) days. Lactation curves were fitted using two empirical (Wood and Wilmink) and two mechanistic models (Dijkstra and Pollott). The parameters of the empirical and mechanistic models were estimated using the iterative non-linear curve fitting procedure in R. The results showed that the estimation of TMY was not affected by the sampling interval. However, the estimation of peak yield (PY) and day at peak yield (TPY) was affected by sampling interval (P < 0.05), with better estimates for 7D and 14D. Estimates of PY and TPY differed between the empirical and mechanistic models with both methods failing to estimate PY and TPY in atypical curves. The Dijkstra model showed the best fit for typical curves and the Pollott model for atypical curves in all the sampling intervals evaluated.</p>","PeriodicalId":23329,"journal":{"name":"Tropical animal health and production","volume":"57 2","pages":"116"},"PeriodicalIF":1.7,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11906548/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143626024","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}