DSpace Communidade: Embrapa Pesca e Aquicultura (CNPASA)

Effect of fish density on trophic interactions and food assimilation in polyculture of tambaqui (Colossoma macropomum) and curimba (Prochilodus lineatus).

2026-06-01T19:48:37Z

Título: Effect of fish density on trophic interactions and food assimilation in polyculture of tambaqui (Colossoma macropomum) and curimba (Prochilodus lineatus). Autoria: LIMA, A. F.; NAHON, S.; RALIEN, P. R.; SILVA, M. S. G. M. e; COSTA, V. E.; AUBIN, J.; VALENTI, W. C. Conteúdo: Determining the optimal combination and proportion of species remains a key challenge for balancing and optimizing nutrient recycling in polyculture systems. The aim of this study was to evaluate diet, food-source utilization, and trophic interactions of tambaqui (Colossoma macropomum) reared in monoculture or in polyculture with curimba (Prochilodus lineatus), using carbon and nitrogen stable isotopes and Ecopath modeling. Three production systems were compared: tambaqui monoculture (0.25 fish m−2) (T), and tambaqui–curimba polycultures with high (0.25 fish m−2) (TC) and low (0.08 fish m−2) tambaqui final densities (TLC). Across all treatments, tambaqui production was primarily supported by feed (<85%), while curimba growth relied on live or dead zooplankton. However, in TLC, the contribution of zooplankton to the curimba diet significantly decreased (from 68% in TC to 44% in TLC), while formulated feed increased (from 5% in TC to 24% in TLC), resulting in an overlap of isotopic niches between both fish species. Polyculture promoted higher ecotrophic efficiency of both feed and zooplankton, as well as higher system omnivory and Finn's cycling index. Polyculture may promote more efficient utilization of natural food resources in the ponds and lead to higher yields compared to monoculture. A high tambaqui density in polyculture (0.25 tambaqui m−2 with 0.30 curimba m−2) minimizes competition with curimba for formulated feed, while enhancing nutrient recovery and overall system efficiency.

Integrating curimba culture during the grow‐out phase of tambaqui affects overall productivity, water quality, and fish health.

2026-06-01T19:48:41Z

Título: Integrating curimba culture during the grow‐out phase of tambaqui affects overall productivity, water quality, and fish health. Autoria: LIMA, A. F.; PEREIRA, A. S.; GANECO-KIRSCHNIK, L. N.; MACIEL-HONDA, P. O.; VALENTI, W. C. Conteúdo: The efficiency of feed use in aquaculture may be improved by integrating the culture of extractive species into fedspecies systems. This study assessed the impact of including curimba (Prochilodus lineatus) in tambaqui (Colossoma macropomum) production during the grow-out phase in earthen ponds. A completely randomized experiment with two treatments (production systems) and three replications of each was conducted over 7 months. Tambaqui monoculture and tambaqui with curimba-integrated culture were compared. The addition of curimba did not affect tambaqui performance, which reached a final weight of 1.7 kg, survival rate of 60%, and feed conversion ratio of 1.73 in both systems; annual productivity reached about 7.1 t ha1. Curimba grew to 144 g, with a survival rate of 97% and annual production of 1.0 t ha1. Data indicated that total fish production (tambaqui + curimba) may be higher (25%) in the integrated culture system. The presence of curimba was associated with lower morning dissolved oxygen and afternoon pH, and higher levels of chlorophyll a, turbidity, and total dissolved and suspended solids in the water. Phytoplankton, zooplankton, and monogenean parasites in tambaqui tended to be higher in the integrated culture system, possibly related to the resuspension of nutrients induced by bioturbation caused by the curimba. Implementing the integrated culture increased net profit by approximately US$ 1.5 thousand per hectare per year. Curimba appears to be compatible with and complementary to tambaqui, making them suitable for co-culture. Therefore, tambaqui can be effectively farmed in an integrated culture with curimba (and possibly other benthic species), enhancing aquaculture production efficiency and aligning with the principles of the circular economy

A bibliometric review about scientific trends and advances on residual feed intake (RFI) and feed efficiency in ruminants.

2026-05-26T17:48:33Z

Título: A bibliometric review about scientific trends and advances on residual feed intake (RFI) and feed efficiency in ruminants. Autoria: FERREIRA, J.; GONÇALVES, L. F.; PAIM, T. do P.; BONILHA, S. F. M.; CYRILLO, J. N. dos S. G.; MERCADANTE, M. E. Z.; ARNANDES, R. H. B.; COSTA, R. L. D. da; MCMANUS, C. Conteúdo: The increasing demand for sustainable livestock production systems has intensified scientific interest in feed efficiency traits, particularly residual feed intake (RFI), as a strategy to improve productivity while reducing environmental impacts. This study provides a comprehensive bibliometric assessment of global scientific production on RFI and feed efficiency in ruminants. A total of 2632 documents indexed in Scopus and Web of Science databases between 2015 and 2024 were analyzed, covering 374 scientific sources and involving 8,406 authors. Scientific output showed a strong and consistent upward trend throughout the study period, with an annual growth rate of 48.9%, particularly from 2019 onwards. Brazil, United States, Australia, Canada, and China were identified as the leading contributors to research development in this field. Authorship patterns revealed a highly collaborative research structure, with an average of 6.97 co-authors per publication, reflecting the interdisciplinary nature of feed efficiency studies. Keyword co-occurrence and network analyses highlighted the close integration of RFI research with themes related to sustainability, methane emissions, genetics, nutrition, and rumen biology. Overall, the results indicate that research on RFI has evolved from a predominantly zootechnical indicator toward a consolidated and sustainability-oriented scientific domain, reinforcing its strategic importance for the development of climate-smart ruminant production systems.

Editorial: Advances in precision livestock management for grazing ruminant systems.

2026-05-26T16:48:38Z

Título: Editorial: Advances in precision livestock management for grazing ruminant systems. Autoria: LIMA, P. de M. T.; PAIM, T. do P. Conteúdo: Este editorial apresenta uma coletânea de pesquisas sobre a gestão de precisão na pecuária (PLM), focando especificamente nos desafios de monitorar ruminantes em sistemas de pastejo extensivos. Os autores destacam que, embora ambientes amplos e heterogêneos dificultem a supervisão humana, o surgimento de tecnologias como sensores, cercas virtuais e inteligência artificial agora permite o acompanhamento contínuo da saúde animal e do impacto ambiental. O texto sintetiza onze estudos globais que utilizam ferramentas inovadoras para aprimorar a eficiência nutricional, o bem-estar e a sustentabilidade da produção de carne e leite. Em última análise, o trabalho funciona como um roteiro para transformar dados digitais em decisões práticas, visando otimizar a produtividade em paisagens complexas.