8 research outputs found
Livestock feed resources used as alternatives during feed shortages and their impact on the environment and ruminant performance in West Africa: a systematic review
No full textRuminant feed is a major problem for the livestock sector in West African developing countries causing animal nutritional diseases, reducing ruminant production, and creating a massive ecological crisis through greenhouse gas emissions. Alternative feeds, which include agro-industrial by-products, fodder trees, crop residues, insects, fodder legumes, algae, and pulses, constitute enormous feed resources for livestock in Africa. This study was conducted in accordance with the methodological recommendations of PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses). We conducted a literature search using Google Scholar, Web of Science, and Scopus to identify documents related to alternative ruminant feeds using the following keywords: alternative feeds, ruminant products, environmental impacts, and West Africa. Those that met the inclusion criteria were included, resulting in 44 articles published between 2013 and 2023. These studies included 45 alternative feeds divided into six groups, including agro-industrial by-products (48.89%), followed by fodder trees (17.78%), crop residues (13.33%), insects (8.89%), fodder legumes (6.67%) and seaweeds (4.44%). Our results revealed that alternative feed resources and their effects on ruminant’s performances and environment are poorly known in West Africa, which limits their inclusion in rations and sometimes leads to their misuse. Future research should focus on these aspects in order to make efficient use of these resources to improve ruminant milk and meat production
Sommaire - 12(3) Septembre 2024
No full textSommaire
Production et Santé Animales
Evaluation des pratiques et moyens de prise en charge des chirurgies digestives dans les cabinets vétérinaires en Afrique de l’Ouest
Sahidi ADAMOU, Rock Allister LAPO, Noureddine BEN CHEHIDA
141-148
Caractéristiques socio-démographiques et techniques des systèmes d’élevage de ruminants et analyse des contraintes de production en Côte d’Ivoire
Adam Camille KOUAME, Gouagoua Séverin KOUADJA, Kouakou Eugène KOUADIO, Pierre TOURE, Kalo Laciné BAMBA, Kouabena KREMAN
149-157
Typologie des élevages de dindons locaux (Meleagris gallopavo) dans les zones agro-écologiques Ouest Atacora et Vivrière du Sud Borgou au Bénin
Cham ALABI, Yaya IDRISSOU, S.A. ASSANI, S.H.S. WOROGO, M. AZALOU, I.T. ALKOIRET
158-163
Prévalence sérologique de la Trypanosomose Animale Africaine (TAA) chez les bovins élevés dans la vallée de la Semuliki, RD Congo
Faustin LITALEMA LOKINDA, Sébastien KAKULE, Jolie OSANDO, Rigobert LITINDI
164-169
Production Végétale et Environnement
Le piège à tissus comme méthode physique innovante de surveillance et de capture au champ de Noorda blitealis, principal ravageur du Moringa
Mamane Sani HALILOU, Ali DOUMMA
170-173
Système de production et importance socio-économiques du taro (Colocasia esculenta (L.) Schott) et du macabo (Xanthosoma sagittifolium Schott) au Bénin
Sylvie TAMADAHO, Gbèdomèdji Hurgues Aristide HOUENON, Rose Fernande FAGBEDJI, Aristide Cossi ADOMOU, Hounnankpon YEDOMONHAN
174-182
Nutrition et Technologie Alimentaire
Consommation, interdits, risques sanitaires, et enjeux de l’élevage des silures en Côte d’Ivoire
Kouamé Benjamin ATTA, Ahou Rachel KOUMI, Bénié Rose Danielle ABOUA, Kadjo Henri Joël NIAMIEN, Boua Célestin ATSÉ, Essétchi Paul KOUAMÉLAN
183-189
Ressources Naturelles et Foresterie
Ethno-zoologie du Dendrocygne veuf (Dendrocygna viduata) dans la vallée du fleuve Niger
Hassane SOUMAILA, Issiaka YOUSSOUFA, Soumana IDRISSA, Abdourhimou AMADOU ISSOUFOU, Ali MAHAMANE
190-195
Rendement des fours traditionnels de production de charbon à Acacia auriculiformis et A. mangium sur le plateau des Batéké, RD Congo
Jean SEMEKI NGABINZEKE, Etienne YUSUFU KACHAKA, Rodrigue DAASSI, Clarin BASUSU MASIMO, Micheline KANI KANI, Jean LEJOLY
196-20
Governing digital innovation in livestock systems: institutional gaps and coordination challenges in Benin
No full textDigital technologies offer transformative potential for livestock systems by enhancing productivity, resource efficiency, and market access. However, institutional and governance challenges often constrain the adoption of such innovations. This study explores how national policies, legal frameworks, and actor configurations influence the development and use of digital tools in Benin’s livestock sector. A qualitative exploratory design was adopted using Ostrom’s Institutional Analysis and Development (IAD) framework. Data were collected through documentary analysis of key legal instruments and strategic plans and unstructured interviews with a diverse group of stakeholders, including public officials, farmer organizations, NGOs, and agri-tech startups. Thematic coding and triangulation were used to analyze how institutional arrangements influence digital innovation in livestock systems. While Benin has established digital and agricultural policies, they lack specificity for livestock systems. Regulatory voids, fragmented governance, and unclear data protection frameworks undermine stakeholder trust and coordination. Stakeholders operate under divergent logics—bureaucratic, commercial, and advocacy-driven—resulting in isolated pilot projects that are unable to scale or integrate into national systems. Institutional exclusion of farmer voices further limits the relevance and uptake of digital tools. The study highlights that without coherent regulatory frameworks, coordinated governance platforms, and inclusive stakeholder participation, digital innovations in livestock systems are unlikely to achieve systemic impact. Effective digital transformation requires sector-specific policy development, multi-stakeholder engagement, and integration of digital services into extension systems. These institutional reforms are essential for realizing digital agriculture’s potential in supporting resilient and equitable livestock livelihoods
Croissance et teneurs en nutriments des juvéniles de Clarias gariepinus élevés en milieu contaminé aux insecticides Emamectine benzoate et Acétamipride
No full textThis study aims to evaluate, under controlled conditions, the effects on growth and biochemical composition of an exposure of Clarias gariepinus to the insecticides Emamectin benzoate and Acetamiprid. Juveniles of C. gariepinus (2.38 ± 0.1 g) were subjected to three sub-lethal concentrations of a commercial product containing the two insecticides (0; 0.25 and 0.50 µl/l) for 28 days. Data collected and assays in the laboratory performed on whole fish, were used to determine the survival rate, growth performance, feed efficiency and nutritional parameters. Results of the study showed that while survival rates were similar for all treatments, the growth of exposed fishes was relatively lower than that of the control. This low growth in contaminated fish is related to the decrease in food intake and feed efficiency. This is due to preferential use of body proteins and some carbohydrates to produce energy in order to cope with chemical stress and energy cost of abnormal behaviors (hyperactivity, rapid swimming, loss of balance, etc.) induced by the insecticides.
Keywords: Exposure, insecticide, Clarias gariepinus, growth, biochemical compositionCette étude vise à évaluer en conditions contrôlées, les effets sur la croissance et la composition biochimique, d’une exposition de Clarias gariepinus aux insecticides Emamectine benzoate et Acétamipride. Ainsi, des juvéniles de C. gariepinus (2,38 ± 0,1 g) ont été soumis à trois concentrations sub-létales d\u27un produit commercial contenant les deux insecticides (0; 0,25 et 0,50 µl/l) pendant 28 jours. Les données collectées et les dosages au laboratoire réalisés sur des poissons entiers, ont permis de déterminer les taux de survie, les performances de croissance, l’efficacité alimentaire et les paramètres nutritionnels. Les résultats de l’étude ont montré que si les taux de survie sont semblables pour tous les traitements, la croissance des individus exposés aux insecticides était relativement inférieure à celle des individus témoins. Cette faible croissance chez les individus contaminés est liée à la baisse de la prise alimentaire et de l’efficacité alimentaire. Ceci est lié à l’utilisation préférentielle des protéines corporelles et d’une partie des glucides pour produire de l’énergie afin de faire face au stress chimique et au coût énergétique des comportements inhabituels (hyperactivité, nage rapide, perte d’équilibre, etc) induits par l’insecticide.
Mots Clés: Exposition, insecticide, Clarias gariepinus, croissance, composition biochimiqu
The functional traits and threats to the Borgou cattle breed as perceived by farmers in Benin
No full textAbstract Benin has been facing the loss of its animal genetic heritage over the years. The aim of this study was to explore the reasons related to the progressive abandonment of the Borgou cattle breed. The assessment of threat level and functional traits related to the Borgou breed was therefore collected through semi-structured interviews from 105 cattle farmers using the Likert scale (1 to 5), and the scores recorded were compared within each group of farmers using the Kruskal–Wallis and the Mann–Whitney U tests. The results showed that depending on the types of farmers surveyed, the Borgou breed is much more threatened by the Zebu Goudali (p > 0.05), Yakana (p > 0.05) and Azawak (p 0.05). Farmers appreciated its qualities such as adaptability, resistance to diseases, fertility, manure production, conformation, aptitude for draught and valorization of food resources (median: 3 to 5). However, scores recorded (medians 2 to 3) for the growth (p > 0.05), milk production (p > 0.05) and selling price (p < 0.01) of Borgou cattle indicated that these traits were unsatisfactory for farmers and reveal that the Borgou breed is mainly discarded in view of its low capacity to swiftly produce meat and its low milk productivity. This leads farmers to resort to cross-breeding through the use of other more productive breeds. This study will therefore allow to take into account farmers’ perceptions in the development of programmes and sustainable in situ conservation strategies of the Borgou cattle breed in Benin
Cesaro bounded operators in Banach spaces
No full text[EN] We study several notions of boundedness for operators. It is known that any power bounded operator is absolutely Cesaro bounded and strongly Kreiss bounded (in particular, uniformly Kreiss bounded). The converses do not hold in general. In this note, we give examples of topologically mixing (hence, not power bounded) absolutely Cesaro bounded operators on l(p)(N), 1 <= p < infinity, and provide examples of uniformly Kreiss bounded operators which are not absolutely Cesaro bounded. These results complement a few known examples (see [27] and [2]). We also obtain a characterization of power bounded operators which generalizes a result of Van Casteren [32]. In [2] Aleman and Suciu asked if every uniformly Kreiss bounded operator T on a Banach space satisfies that. We solve this question for Hilbert space operators and, moreover, we prove that, if T is absolutely Cesaro bounded on a Banach (Hilbert) space, then parallel to T-n parallel to = o(n) ((parallel to Tn parallel to=o(n12), respectively). As a consequence, every absolutely Cesaro bounded operator on a reflexive Banach space is mean ergodic.The first, second and fourth authors were supported by MINECO and FEDER, Project MTM201675963-P.
The third author was supported by grant No. 17-27844S of GA CR and RVO: 67985840.
The fourth author was also supported by Generalitat Valenciana, Project PROMETEO/2017/102.Bermúdez, T.; Bonilla, A.; Muller, V.; Peris Manguillot, A. (2020). Cesaro bounded operators in Banach spaces. Journal d Analyse Mathématique. 140(1):187-206. https://doi.org/10.1007/s11854-020-0085-8S1872061401A. Albanese, J. Bonet and W. J. Ricker, Mean ergodic operators in Fréchet spaces, Ann. Acad. Sci. Fenn. Math. 34 (2009), 401–436.A. Aleman and L. Suciu, On ergodic operator means in Banach spaces, Integral Equations Operator Theory 85 (2016), 259–287.I. Assani, Sur les opérateurs à puissances bornées et le théorème ergodique ponctuel dans Lp[0, 1], 1 < p < ∞, Canad. J. Math. 38 (1986), 937–946.M. J. Beltrán-Meneu, Operators on Weighted Spaces of Holomorphic Functions, PhD Thesis, Universitat Politècnica de Valencia, Valencia, Spain, 2014.M. J. Beltrán, J. Bonet and C. Fernández, Classical operators on weighted Banach spaces of entire functions, Proc. Amer. Math. Soc. 141 (2013), 4293–4303.M. J. Beltrán, M.C. Gómez-Collado, E. Jordá and D. Jornet, Mean ergodic composition operators on Banach spaces of holomorphic functions, J. Funct. Anal. 270 (2016), 4369–4385.N. C. Bernardes, Jr., A. Bonilla, V. Müller and A. Peris, Distributional chaos for linear operators, J. Funct. Anal. 265 (2013), 2143–2163.N. C. Bernardes, Jr., A. Bonilla, A. Peris and X. Wu, Distributional chaos for operators in Banach spaces, J. Math. Anal. Appl. 459 (2018), 797–821.J. Bonet, Dynamics of the differentiation operator on weighted spaces of entire functions, Math. Z. 261 (2009), 649–657.Y. Derriennic, On the mean ergodic theorem for Cesaro bounded operators, Colloq. Math. 84/85 (2000), 443–455.Y. Derriennic and M. Lin, On invariant measures and ergodic theorems for positive operators, J. Funct. Anal. 13 (1973), 252–267.R. Émilion, Mean-bounded operators and mean ergodic theorems, J. Funct. Anal. 61 (1985), 1–14.A. Gomilko and J. Zemánek, On the uniform Kreiss resolvent condition, (Russian) Funktsional. Anal. i Prilozhen. 42 (2008), 81–84A. Gomilko and J. Zemánek, English translation in Funct. Anal. Appl. 42 (2008), 230–233.K.-G. Grosse-Erdmann and A. Peris, Linear Chaos, Springer, London, 2011.B. Z. Guo and H. Zwart, On the relation between stability of continuous- and discrete-time evolution equations via the Cayley transform, Integral Equations Operator Theory 54 (2006), 349–383.B. Hou and L. Luo, Some remarks on distributional chaos for bounded linear operators, Turk. J. Math. 39 (2015), 251–258.E. Hille, Remarks on ergodic theorems, Trans. Amer. Math. Soc. 57 (1945), 246–269.I. Kornfeld and W. Kosek, Positive L1operators associated with nonsingular mappings and an example of E. Hille, Colloq. Math. 98 (2003), 63–77.W. Kosek, Example of a mean ergodic L1operator with the linear rate of growth, Colloq. Math. 124 (2011), 15–22.U. Krengel, Ergodic Theorems, Walter de Gruyter, Berlin, 1985.C. Lubich and O. Nevanlinna, On resolvent conditions and stability estimates, BIT, 31 (1991), 293–313.C. A. McCarthy, A Strong Resolvent Condition does not Imply Power-Boundedness, Chalmers Institute of Technology and the University of Göteborg, Preprint No. 15 (1971).A. Montes-Rodríguez, J. Sánchez-Álvarez and J. Zemánek, Uniform Abel—Kreiss boundedness and the extremal behavior of the Volterra operator, Proc. London Math. Soc. 91 (2005), 761–788.V. Müller and J. Vrsovsky, Orbits of linear operators tending to infinity, Rocky Mountain J. Math. 39 (2009), 219–230.O. Nevanlinna, Resolvent conditions and powers of operators, Studia Math. 145 (2001), 113–134.J. Neveu, Mathematical Foundations of the Calculus of Probability, Holden-Day, San Francisco, Calif.-London-Amsterdam, 1965.A. L. Shields, On Möbius Bounded operators, Acta Sci. Math. (Szeged) 40 (1978), 371–374.J. C. Strikwerda and B. A. Wade, A survey of the Kreiss matrix theorem for power bounded families of matrices and its extensions, in Linear Operators, Polish Acad. Sci., Warsaw, 1997, pp. 339–360.L. Suciu, Ergodic behaviors of the regular operator means, Banach J. Math. Anal. 11 (2017), 239–265.L. Suciu and J. Zemánek, Growth conditions on Cesàro means of higher order, Acta Sci. Math (Szeged) 79 (2013), 545–581.Y. Tomilov and J. Zemánek, A new way of constructing examples in operator ergodic theory, Math. Proc. Cambridge Philos. Soc. 137 (2004), 209–225.J. A. Van Casteren, Boundedness properties of resolvents and semigroups of operators, in Linear Operators, Polish Acad. Sci. Inst. Math., Warsaw, 1997, pp. 59–74
Differences in the gas and dust distribution in the transitional disk of a sun-like young star, PDS 70
No full textThis is the author accepted manuscript. The final version is available from the publisher via the DOI in this recordThe American Astronomical Society. All rights reserved. We present ALMA 0.87 mm continuum, HCO + J = 4-3 emission line, and CO J = 3-2 emission line data of the disk of material around the young, Sun-like star PDS 70. These data reveal the existence of a possible two-component transitional disk system with a radial dust gap of 0.″42 ±0.″05, an azimuthal gap in the HCO + J = 4-3 moment zero map, as well as two bridge-like features in the gas data. Interestingly these features in the gas disk have no analog in the dust disk making them of particular interest. We modeled the dust disk using the Monte Carlo radiative transfer code HOCHUNK3D using a two-disk component. We find that there is a radial gap that extends from 15 to 60 au in all grain sizes, which differs from previous work.This work is supported supported by the NASA XRP grants NNX17AF88G and NNX16AJ75G. MC thanks the support from the Centro de Astrofísica de Valparaíso. S.K. acknowledges support from an STFC Rutherford Fellowship (ST/J004030/1) and ERC Starting Grant (Grant Agreement No. 639889). This work is supported by the Astrobiology Center Program of National Institutes of Natural Sciences (NINS) (Grant Number: AB281013) and by MEXT KAKENHI No. 17K05399 (EA). Y.H. is currently supported by Jet Propulsion Laboratory, California Institute of Technology, under a contract from NASA. This paper makes use of the following ALMA data: ADS/JAO.ALMA#2015.1.00888.S. ALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada), MOST and ASIAA (Taiwan), and KASI (Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO, and NAOJ. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, In
Investigating the effects of large wood and forest management on flood risk and flood hydrology
No full textThe changes to catchment scale flood risk following river restoration works, including the addition of large wood logjams to the channel, are poorly quantified in the literature. Key concerns following river restoration for river managers and other stakeholders are changes to flood hydrology at the reach and catchment scale and changes in the mobility of large wood pieces. The effects of accumulations of large wood (logjams) on local flood hydrology have been documented in the literature, showing logjams slow flood wave travel time and increase the duration and extent of local overbank inundation. Modelling studies conducted at a reach scale have shown that these local effects can slow flood wave travel time through a reach and delay the timing of flood peak discharge at the reach outflow. How these local and reach scale effects translate to the catchment scale remains to be illustrated in the literature.In this thesis a combination of field and modelling studies are used to; elucidate the link between logjam form and function, to quantify the mobility of pieces of large wood relative to their physical characteristics, to predict the changes in floodplain forest restoration over time and to provide predictions of changes to catchment scale flood hydrology following river restoration at a range of scales and locations.It is shown that logjams inducing a step in the water profile are most effective at creating diverse geomorphology and habitats. Logjams were found to account for 65% of flow resistance in forested river channels, rising to 75-98% of flow resistance where the logjam was inducing a step in the water profile.Large wood in small forested river channels was found to be highly mobile with 75% of pieces moving, with the longest transport length of 5.6km. Large wood mobility is governed primarily by the length of a piece of wood with wood in excess of 1.5x channel width a threshold for a lower probability of movement.Hydrological modelling using OVERFLOW shows that reach scale river restoration can lead to modest changes in catchment scale flood hydrology. It is concluded that flood risk management can incorporate river restoration, but that results are likely to be unpredictable if engineered logjams are used alone. Substantial benefits in reducing catchment outflow peak discharge (up to 5% reduction) are modelled for floodplain forest restoration at the sub-catchment scale (10-15% of catchment area), rising to up to 10% reductions as the forest matures and becomes more complex
