Tropical animal health and production最新文献

{"title":"Timing of supplementation on intake and grazing behavior dairy cows.","authors":"Citlali Anais Castro Jaime, María Magdalena Crosby Galvan, Juan Andrés Burgueño Ferreira, Rodolfo Ramírez Valverde, Juan Daniel Jiménez Rosales, Ricardo Daniel Améndola Massiotti","doi":"10.1007/s11250-025-04354-2","DOIUrl":"https://doi.org/10.1007/s11250-025-04354-2","url":null,"abstract":"<p><p>The objective was to evaluate the response of New Zealand Holstein cows to concentrate supplementation at contrasting times of the day on herbage intake and ingestive behavior. Two experiments were conducted in winter and spring-summer in a grazing dairy production system of Medicago sativa L. with Dactylis glomerata L. pastures. Three moments of supplying 5.0 kg DM concentrate cow^-1 d^-1 were used: AM after morning milking, PM after afternoon milking, and the AM-PM control equally dividing that amount after both milkings. The experimental units were groups of six cows in winter (a total of 18 cows) and five cows in spring-summer (a total of 15 cows), additionally their respective grazed areas were also considered as experimental units. The design used was a three × three (treatments × periods) cross-over; the allotment of groups to the treatments was consecutive and randomized. The management criterion of rotational grazing was 8 cm of residual forage height for all treatments. Each time the target height of residual herbage was reached, the portable electric fence was manually moved forward allowing on average 36 m² fresh pasture. In winter, intake was not different (P < 0.5) between treatments; however, during spring-summer it was 8% lower (P < 0.005) with AM supplementation. There was no effect (P > 0.5) of treatments on total grazing time, rumination and other activities. In conclusion, AM supplementation in spring-summer resulted in dominant evening grazing, and herbage was utilized at its time of highest nutrient concentration.</p>","PeriodicalId":23329,"journal":{"name":"Tropical animal health and production","volume":"57 2","pages":"94"},"PeriodicalIF":1.7,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143543392","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":"Comparative efficacy of commercial phytases on phosphorus availability for broilers.","authors":"Rosa Aparecida Reis de Léo, Jean Kaique Valentim, Rafael de Sousa Ferreira, Thaisa Pereira de França, Artur Macedo Ribeiro, Kaique Moreira Gomes, Alexander Alexandre de Almeida, Arele Arlindo Calderano","doi":"10.1007/s11250-025-04343-5","DOIUrl":"https://doi.org/10.1007/s11250-025-04343-5","url":null,"abstract":"<p><p>The presence of phytate in broiler diets restricts phosphorus availability, a crucial nutrient for muscle and bone development, leading to reduced performance. To alleviate this issue, exogenous enzymes such as phytase are introduced; however, the wide variety of phytases available on the market and their effectiveness are not yet fully understood. The objective of this study was to evaluate the phosphorus equivalence of commercial phytase in broiler diets, using the standard curve, and its effects on performance, bone mineralization, intestinal histological integrity, liver relative weight, and total alkaline phosphatase in the initial phase (1 to 21 days) of broiler. We used 2,500 male broiler chickens, with an initial weight of 44 g, distributed in a completely randomized design with 10 treatments and 10 replications of 25 birds per experimental unit. The diets were formulated to meet the nutritional requirements of the birds, except for the available phosphorus (Pd) and calcium content. The treatments were divided as follows: T1-Control (CT) with 0.18% Pd; T2-CT + 0.07% aP; T3-CT + 0.14% aP; T4-CT + 0.21% aP; T5-CT + phytase 1; T6-CT + phytase 2; T7-CT + phytase 3; T8-CT + phytase 4; T9-CT + phytase 5; and T10-CT + phytase 6. For enzymatic standardization, 500 FTU/kg (Phytase Units) of each enzyme were used. Animals subjected to the highest levels of P (T2, T3, and T4) and with the addition of commercial phytases (T5, T6, T7, T8, T9, and T10) had better performance and bone mineralization results when compared to T1-CT. All phytases evaluated improved final live weight, weight gain, feed conversion, and ash and phosphorus content in the tibia and intestinal development compared to CT. Supplementing broiler diets with commercial phytases enhances performance, bone mineralization, and jejunal development from 1 to 21 days.The average phosphorus availability from phytic acid in these phytases was 0.154%. The comparison of the six commercial phytases in diets for broiler chickens, using the standard curve and supplementation with 25 g/t of commercial phytase, showed similar results, promoting improvements in performance, bone mineralization, and jejunal development.</p>","PeriodicalId":23329,"journal":{"name":"Tropical animal health and production","volume":"57 2","pages":"93"},"PeriodicalIF":1.7,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143543386","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":"Expression and characterization of the immunogenicity of rec-gp45 of Babesia bigemina using cattle.","authors":"Zia-Ul-Rehman, Sarfraz-Ur-Rahman, Kamran Ashraf, Muhammad Suleman, Sikandar Ali, Muhammad Imran Rashid","doi":"10.1007/s11250-025-04350-6","DOIUrl":"https://doi.org/10.1007/s11250-025-04350-6","url":null,"abstract":"<p><p>Bovine Babesiosis (BB) is a tick-borne blood protozoan disease caused by Babesia, worldwide. The disease in tropical and subtropical regions is caused by B. bovis and B. bigemina. The main aim of this study was to develop the rec-gp45 of B. bigemina and to do experiments for the conduction of promising immunogenic trials on calves. Initially, microscopy was performed to identify B. bigemina through a thin blood smear, and DNA extraction was done. Subsequently, PCR was performed to amplify the gp45 sequence. Transformation of pET28α-gp45 into BL-21 was done by heat shock method. The rec-gp45 was identified at 39 kDa through SDS-PAGE and Western blot analyses. Indirect ELISA was performed to check specificity and sensitivity. Flow cytometry was also performed to assess the cellular responses following inoculation of rec-gp45 in calves. Indirect ELISA showed the specificity and sensitivity 100%, respectively. The immunogenic responses against BB in calves were checked through flow cytometry and we found 29.96% of CD8 + and 1.390% of CD4 + T cells, whereas cellular and humoral responses were shown against BB and it showed specific IgG response with OD value 2.460 ± 0.3151. The recombinant protein gp45 can be a promising immunogenic candidate against B. bigemina.</p>","PeriodicalId":23329,"journal":{"name":"Tropical animal health and production","volume":"57 2","pages":"92"},"PeriodicalIF":1.7,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143543387","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":"Impact of feeding Murraya koenigii and Aegle marmelos leaves on metabolic and reproductive performance in crossbred cows.","authors":"Juli Chakma, Narayan Dutta, Sunil Ekanath Jadhav, Sanjay Kumar Singh, Divyaprakash Ramjibhai Choravada, Abhijeet Champati, Sonali Namdeo, Navneet Kaur","doi":"10.1007/s11250-025-04351-5","DOIUrl":"https://doi.org/10.1007/s11250-025-04351-5","url":null,"abstract":"<p><p>The study was carried out to ascertain the effect of feeding herbal formulation (A. marmelos and M. koenigii) on metabolic profile and reproductive performance of crossbred cows. Crossbred cows (24) were randomly assigned to four treatment groups. Cows in CON (control) group were fed a diet comprised of green fodder, concentrate and wheat straw, while, the cows in HP (herbal powder), HPL (herbal pellets) and HEX (herbal extract) groups were offered CON diet having herbal powder (200gd^-1), herbal pellets (200gd^-1) and methanolic herbal extract (equivalent to 200 g herbal powder d^-1), respectively. The cows were fed on treatment diets for 7 d and continued with CON diet up to one month. Hb levels were analogous among the treatments; however, haematocrit values were significantly higher (P < 0.05) in the HEX group relative to CON. Total protein, albumin, globulin, A:G ratio, serum glucose, total cholesterol, AST and ALT were comparable across the dietary treatments. Serum NEFA, urea and creatinine were lower (P < 0.01) in treatment groups relative to CON. Serum minerals viz. i-P, Cu, Zn, Mn and iron were significantly (P < 0.01) higher in all the treatments than CON. The conception at first insemination was considerably higher in HPL, HEX and HP groups relative to CON. Spinnbarkeit and pH values of cervical mucus were noticeably higher in HP, HPL and HEX groups. The typical fern pattern of cervical mucus exhibited higher conception rate in treatment groups. It may be concluded that the herbal formulation positively influenced metabolic parameters and reproductive performance in post-partum crossbred cows.</p>","PeriodicalId":23329,"journal":{"name":"Tropical animal health and production","volume":"57 2","pages":"90"},"PeriodicalIF":1.7,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143543388","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 propolis extract supplementation in breeder and broiler diets and it's in ovo injection on immune status, blood parameters, vaccine-antibody response and intestinal microflora of broiler chick.","authors":"Kalbiye Konanc, Ergin Ozturk","doi":"10.1007/s11250-025-04329-3","DOIUrl":"10.1007/s11250-025-04329-3","url":null,"abstract":"<p><p>This study evaluated the effects of dietary propolis extract supplementation and in-ovo propolis injection on the immune status, blood parameters, vaccine-antibody response, and intestinal microflora of broiler chickens. A total of 600 Ross 308 broiler chicks were used. Breeder diets were supplemented with 400 ppm propolis extract (P) or left unsupplemented (C) during weeks 38-39. Eggs from the control group (C) were divided into four groups, with in-ovo injections of 400 ppm propolis extract (C-iP) or physiological saline (C-iS) on day 18 of incubation. Untreated eggs formed the control (C-C) or propolis-supplemented (P-C) groups. Chicks were fed either a basal diet (C) or a diet supplemented with 400 ppm propolis extract (P), forming six experimental groups: C-C, C-P, P-C, P-P, C-iP, and C-iS, with 10 replicates per group (10 chicks per replicate). Propolis supplementation significantly increased immunoglobulin levels (IgA, IgG, IgM) compared to the control group. Although it positively affected certain blood parameters, no significant differences were found in post-vaccination antibody titers. The C-C group had the highest total antioxidant levels, while total oxidant levels and oxidative stress index were lowest in the P-P group. Despite positive effects on blood parameters and intestinal microflora, no significant improvements in growth performance were observed. Nevertheless, propolis extract shows potential as an immune enhancer for broiler chickens through parental feeding, standard diets, or in-ovo injection.</p>","PeriodicalId":23329,"journal":{"name":"Tropical animal health and production","volume":"57 2","pages":"89"},"PeriodicalIF":1.7,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143537729","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":"The first report of schmallenberg virus seroprevalence and associated risk factors in cattles in northern Algeria.","authors":"Karima Benfodil, Abdellah Mohamed Cherif, Samir Ansel, Amine Abdelli, Khatima Ait-Oudhia","doi":"10.1007/s11250-025-04349-z","DOIUrl":"https://doi.org/10.1007/s11250-025-04349-z","url":null,"abstract":"<p><p>Schmallenberg virus (SBV) is an arbovirus belonging to the Peribunyaviridae family. It is spread by many biting midges of Culicoides spp genus. In cattle, SBV infection can lead to sporadic abortions, as well as significant reproductive issues, including congenital malformations in newborns and stillbirths. Our study aimed to assess the seroprevalence of schmallenberg virus infection in cattles using indirect ELISA test, and identifying related risk factors. A total of 370 blood samples were randomly collected from cattles of six districts in north Algeria (Algiers, Blida, Bouira, Boumerdès, Tipaza, and Tizi Ouzou). A questionnaire was performed in order to collect zootechnical parameters data, clinical signs, and geographic location. A seroprevalence of 44% (CI95%, 39 - 49.2%) was revealed. Univariate analyses and multivariate logistic regression were used to assess related risk factors with SBV infection. The findings showed that animals older than 2 years, those in the third stage of pregnancy, and cattle exhibiting symptoms like diarrhea had the highest rates of SBV infection. This study demonstrated that the Schmallenberg virus is endemic in cattle within the investigated region. Effective control of arboviruses is vital for both public health and animal health. To enhance vector disease management for SBV and reduce the risk of its spread to non-endemic regions in Algeria, it is important to establish entomological surveillance as soon as possible.</p>","PeriodicalId":23329,"journal":{"name":"Tropical animal health and production","volume":"57 2","pages":"91"},"PeriodicalIF":1.7,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143543389","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":"Relationship between feed efficiency and reproductive traits in precocious Nelore heifers.","authors":"Renata Brandão de Gois, Tiago do Prado Paim, Rogério Fonseca Guimarães Peres, Karen Martins Leão, Camila Alves Dos Santos, Adriana Luize Bocchi, Josiel Ferreira","doi":"10.1007/s11250-025-04342-6","DOIUrl":"https://doi.org/10.1007/s11250-025-04342-6","url":null,"abstract":"<p><p>Residual feed intake (RFI) is one of the most used measure to assess feed efficiency. Animals with a negative RFI are considered more efficient, as they consume less feed than predicted for the observed weight gain. The RFI measures are commonly adjusted for subcutaneous fat thickness, however the energy efficiency detected by RFI may arise from reduced accumulation of visceral fat, an important energy storage for females during the reproductive cycle. Thus, the hypothesis evaluated here is that more efficient Nelore heifers have a lower body energy reserve, harming your reconception after the first calving as early primiparous (close to 24 months of age). Therefore, the present study aimed to evaluate whether there is a relationship between RFI adjusted for subcutaneous fat thickness and the reconception ability of early primiparous Nelore females and the relationships between growth, carcass traits, and reproduction according to RFI classification. Low and not significant correlations (phenotypic and genetic) were observed between RFI and reproductive traits, such as days to first conception (DFC), days to second conception (DSC), first gestation length (FGL), second gestation length (SGL), probability of second conception (PSC) and probability of second parturition (PSP). Reproductive traits exhibited low heritability (< 0.15), indicating limited potential for genetic selection in a tropical environment. In addition, the RFI classification had no influence on reproductive aspects. The results observed suggest that selection for more efficient animals did not affect the reconception of early primiparous females in the evaluated environment. However, these results can be affected by the environmental challenge imposed on these females. Therefore, obtaining similar data in other rearing environments would be interesting to explore the genotype by environment interaction in these traits' relationships. These findings are specific to the tested tropical environment, and the low heritability of reproductive traits may limit the potential for genetic improvement.</p>","PeriodicalId":23329,"journal":{"name":"Tropical animal health and production","volume":"57 2","pages":"88"},"PeriodicalIF":1.7,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143537732","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":"Equalizing light and heavy litters with extra piglet relative to sow functional teats: impacts on lactational performance.","authors":"Laura Dos Santos, Gabriela Piovesan Zanin, Ingrid Camargo Lima, Ana Paula Gonçalves Mellagi, Fernando Pandolfo Bortolozzo, Rafael da Rosa Ulguim","doi":"10.1007/s11250-025-04359-x","DOIUrl":"https://doi.org/10.1007/s11250-025-04359-x","url":null,"abstract":"<p><p>This study evaluated the effects of litter equalization with different weights and numbers of piglets relative to the number of functional teats on sow and piglet performance during lactation. Litters (n = 183) were equalized based on weight (light: 0.955-1.289 kg; heavy: ≥ 1.399-1.935 kg) and piglet number by total number of functional teats (Eq-0: same number of piglets and teats; Eq + 1: one extra piglet than the teat number). Sow body condition was evaluated during lactation. Piglets were individually weighed and evaluated for face, body, and joint injuries. Females lost more caliper units in heavy litters (-0.39; P = 0.05), with no interaction with Eq-0 or Eq + 1 (P = 0.11). There was no difference in the total number of piglets weaned (P ≥ 0.08) regardless of litter weight, number of piglets by functional teats, or their interaction. Weaning weight and average daily gain were positively affected (P < 0.01) in heavy (6.1 ± 0.1 kg; 227.9 ± 0.3 g/d) compared to light litters (5.5 ± 0.1 kg; 214.0 ± 0.3 g/d). Mortality was not affected by different groups (P ≥ 0.60). However, the percentage of piglets removed before weaning was higher for Eq + 1 (5.21 ± 0.75%) than Eq-0 litters (2.66 ± 0.49%; P < 0.01). Heavy litters had a higher percentage of piglets with facial, body, and joint injuries compared to light litters, regardless of the number of piglets by functional teats. Equalizing litters with one extra piglet resulted in a higher pre-weaning piglet removal rate. Body parameters of sows were not compromised comparing Eq-0 and Eq + 1.</p>","PeriodicalId":23329,"journal":{"name":"Tropical animal health and production","volume":"57 2","pages":"87"},"PeriodicalIF":1.7,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143537730","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":"The effects of naked neck and frizzle genes on the fertility, hatchability, egg quality and pterylosis of locally developed commercial layer parent lines.","authors":"Gregory Tamba Dunga, Kwaku Adomako, Bernard Ato Hagan, Jacob Alhassan Hamidu, Oscar Simon Olympio","doi":"10.1007/s11250-025-04335-5","DOIUrl":"https://doi.org/10.1007/s11250-025-04335-5","url":null,"abstract":"<p><p>In this study, the effects of feather cover and feather colour genotypes and their interactions on the fertility, hatchability, external and internal egg qualities of 24-week-old locally developed layer parent lines were assessed. A 2 x 3 factorial experiment laid out in a randomized complete block design of two feather colour variants (brown and white) and three feather cover genotypes (naked neck, frizzle and normal feather) was used for this study. A total of 3,196 eggs from 360 layers of three feather genotypes were set for incubation. Data on fertility, hatchability, egg quality characteristics and chick weight were analysed using the PROC MIXED of SAS and differences between means were separated using LSD at 5% probability level. Percentage fertility of eggs of naked neck and frizzle feathered birds were significantly higher (p<0.05) than those in the normal feathered birds (71.98%, 70.29% vs 63.17%). Eggs of frizzle feathered birds (76.81%) recorded higher (p<0.05) hatchability than those of the naked neck (65.07%) and normal feathered birds (59.64%). Feather cover genotype had no significant difference (p>0.05) on weight of day-old chick. Feather colour genotype significantly (p<0.05) influenced egg weight but not other external egg characteristics. Feather cover and colour genotypes had significant (p<0.05) effect on some of the internal egg qualities. Follicle numbers in the ventral, dorsal and lateral regions were lower (p<0.05) in the naked neck birds relative to the frizzle and normal feathered birds. The incorporation of F and Na alleles into layer parent stocks in hot humid areas could improve fertility, hatchability and egg quality traits of birds.</p>","PeriodicalId":23329,"journal":{"name":"Tropical animal health and production","volume":"57 2","pages":"86"},"PeriodicalIF":1.7,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143524547","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":"Greenhouse gas emissions from Fleckvieh cattle production systems in the Amazon region, Peru.","authors":"Deysi Ruiz-Llontop, Segundo M Portocarrero-Villegas, Hugo Frias, Luis Murga, Joe Mantilla-Oliva, Dante M Pizarro, José Velarde-Guillén, José Américo Saucedo-Uriarte","doi":"10.1007/s11250-025-04358-y","DOIUrl":"10.1007/s11250-025-04358-y","url":null,"abstract":"<p><p>This study aimed to quantify the carbon footprint (CF) from Fleckvieh cattle production systems in the Amazon region of Peru. Ten farms distributed across four provinces: Chachapoyas (System I; n = 2), Bongara (System II; n = 4), Rodriguez de Mendoza (System III; n = 2), and Utcubamba (System IV; n = 2) were assessed. Parameters such as average live weight, animal units (AU), dry matter intake, fat and protein-corrected milk (FPCM), digestibility, and protein content of consumed forage were analyzed. CF was calculated using the 2019 Refinement to 2006 IPCC guidelines. The database was analyzed using analysis of variance and Duncan's statistical test (p < 0.05) to compare the systems. A Pearson correlation was carried out to observe the variables association level. Results revealed a CF of 2.50, 2.70 and 2.65 kg CO₂eq/kg FPCM by biophysical allocation, according to Global Warming Potential 2007, 2014 and 2021, respectively. Enteric methane (82.6%) and nitrous oxide from manure management (17.2%) were the main contributors to greenhouse gas emissions. Positive correlations were found between methane and nitrous oxide emissions whit total FPCM (r = 0.94), total AU (r = 0.99), and low-producing animals (r = 0.96). System I exhibited the lowest enteric methane emissions, suggesting better livestock and feed management. The study highlights the need to optimize herd composition, increase production levels, and reduce low-producing animals to mitigate CF. Additionally, improving forage quality (increasing the digestibility) enhances milk production, securing the economic well-being of smallholder farmers and agricultural sustainability in the Amazon region.</p>","PeriodicalId":23329,"journal":{"name":"Tropical animal health and production","volume":"57 2","pages":"83"},"PeriodicalIF":1.7,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11868227/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143516449","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}