Rendimiento de leche derivado de energía y proteína de vacas en pastoreo recibiendo suplementos en un sistema agrosilvopastoril

Dual purpose farms southwest of the State of Mexico produce milk and calves under subtropical agrosilvopastoral systems (ASPS). During the dry season, farmers supplement their cattle due to the low availability and quality of grasses, without considering, besides grasses, the contribution of woody species to dry matter intake, metabolizable energy (ME), and crude protein (CP) requirements of cows. The aim of this study was to determine milk produced from forage energy (MFe) and protein (MFp) of grazing cow with three types of supplement. First supplement consisted of cracked maize and commercial concentrate resulting on 14 % of CP (S14). To the S14 mixture 7 % of soybean meal was added to increase CP to 16 % (S16), and commercial concentrate of 16 % CP was used as a third supplement (SC16). Six lactating cows were allocated in a 3x3 replicated Latin Square (three cows per square), three experimental periods (EP) (three weeks per EP). There were no significant effects of supplements (P=0.80) on performance variables. Mean milk yield was 6.8 kg/cow/d. Milk from forage energy and protein were 0.8 and 6.1 kg/cow/day, respectively. Mean milk urea nitrogen (MUN) was high regardless of supplement; but nitrogen in urine (44.1 mg/dL) and feces (1.4 mg/g) were higher for SC16 (P=0.001 and 0.04, respectively). Cows obtained 90 and 10 % of their CP and metabolizable energy requirements for maintenance and production from the agrosilvopastoral system.

Accounting for carbon exchanges in a semiarid oak savanna (dehesa).

<p>Semiarid oak savannas (grasslands with scattered trees), partially covered, subject to regular droughts, grazing, and high levels of solar radiation, are nonetheless, typically carbon sinks regarding CO2. However, dehesas are a productive system, a trait shared with other savannas, and they are shaped by their uses for economic production. One of its multiple uses, livestock extensive farming, key to its economic profitability and to the preservation of the agrosilvopastoral system structure, modifies the Greenhouse gas (GHG) balance by adding a significant amount of CH4 and N2O into the cycle. Recent reports and publications have evaluated and compared different types of livestock management within the context of climate change. GHG emissions, extensive use of the soil resource, or the introduction of nitrogen into the system, are some of the generated effects that cause a negative evaluation of extensive farming. Nevertheless, the importance of this sector, given its extension and impact on production and rural development, demands a more rigorous evaluation. It is necessary to precisely account for the fluxes in their totality (including the CO2 sink effect) and the relationships between them. Currently, there are few studies that determine the GHG balance of dehesas, and they are mainly centred on CO2 fluxes without integrating the influence of livestock, or in meadows without a tree layer (which changes the CO2 balance). The net global warming potential of dehesas is unknown, given that very few direct and long-term flux measurements have been taken on them. In this work, CO2 and H2O fluxes from an eddy covariance tower located in an Andalusian dehesa were processed (standard corrections), filtered and homogenized, including filling gaps using artificial neural networks. We calculated the annual CO2 budget since 2015, to assess the sink/source nature of the area. In a modeling exercise to be able to close the carbon cycle, we estimated CH4 and N2O depending on the number of livestock present in the area by season/year, evaluating the tipping point.</p>

ASSESSMENT OF AGROFORESTRY ADOPTION AMONG THE SUBSISTENCE FARMERS IN TSAFE LOCAL GOVERNMENT AREA OF ZAMFARA STATE, NIGERIA

The study was designed to determine what model(s) is (are) practiced, to determine the tree species preferred by people for agroforestry, to identify the problems being encountered by farmers. The study revealed that, adaptation of Agroforestry practice in Tsafe Local Government is up to 88.75% and only11.25% are not into the system. Also by looking into the determined rate of Agroforestry model in the study area, Agrosilvicultural is highest Agroforestry model system which constituted 76.8%, silvopastoral system (4.9%), Agrosilvopastoral system (16.2%) and others have the minimum of 2.1%. 64.8% of respondents intercropped their arable crops with fruit bearing tree. Maize and rice are the major food crops grown in the study area. The study area is faced with inadequate funds (31.0%), poor government intervention (38.0%) and lack of awareness and education (20.4%). An agroforestry system can be considered as a type of land use that is specific to a locality and described according to its biological composition and arrangement, level of technical management as social-economic features. It is recommended that government should provide Agroforestry regulatory policies, means of enlightenments, incentives and supports to improve the practice.

Forage production and productive performance of Nellore heifers in agrosilvopastoral systems

Agrosilvopastoral system is a type of production that involves the soil-forage-animal interface, both of which are benefited by the system. Hence, the present study evaluated the effects of agrosilvopastoral system on the quantitative and qualitative characteristics from pasture, and the animal performance during the feeding period of Nellore heifers. The treatments included: Soil-forage-animal – 357 eucalyptus trees per hectare (LFA14x2m); Soil-forage-animal – 227 eucalyptus trees per hectare (LFA22x2m); and Soil-animal – Five native trees remaining per hectare (CON). The forage used was Brachiaria brizantha cv. BRS Piatã and having as trees planted the Eucalyptus urograndis clones H 13. Treatment effects (P <0.05) for forage accumulation and pasture height, which were lowest in LFA14x2m compared to the others. Total forage dry mass in CON treatment was significantly greater (P <0.05) compared to the other treatments, showing maximum production in March. The LFA14x2m treatment was favorable for greater forage quality, showing an effect on chemical composition (P <0.05), compared to other treatments. Whereas, in November the LFA22x2m treatment was better for neutral detergent fiber. January and March, the treatments were similar (P >0.05) for average daily gain, while in November period, LFA14x2m treatment showed the lowest value (P <0.05). The lowest weight gain by area (November) occurred in the LFA14x2m treatment (P <0.05), although in March the LFA14x2m treatment stocking rate was similar to the others. Forage production and animal performance are altered by the trees densification in agrosilvopastoral systems. The chemical composition of pasture is better in systems with a higher trees density.

Structure et Régénération des Peuplements naturels de Balanites Aegyptiaca (L.) Del. et Ziziphus Mauritiana Lam. suivant un Gradient écologique dans la Région de Maradi au Niger

Les espèces ligneuses jouent un rôle important dans la vie des populations locales. Parmi les espèces couramment utilisées au Niger figurent Balanites aegyptiaca et Ziziphus mauritiana. Ces deux espèces sont exploitées comme sources alimentaires et pour divers produits médicinaux, avec comme conséquence une réduction de leurs peuplements. La présente étude vise à analyser la structure des peuplements et les modes de régénération des deux espèces dans deux secteurs agro-écologiques contrastées de la région de Maradi au centre sud du Niger. Au total, 60 relevés ont été délimités, d’une part dans des formations naturelles dominées par ces espèces, et d’autre part dans les systèmes agrosylvopastoraux des secteurs sahélien et sahélo-soudanien. Dans chaque placette et sur chaque arbre, le diamètre à 1,30 m au rasdu sol , la hauteur totale et deux diamètres perpendiculaires de houppier ont été mesurés. L’inventaire de la régénération a été effectué dans 5 placeaux. La nature de la régénération (drageon, marcotte, semis naturel), la hauteur totale et le nombre de tiges de chaque plantule ont été notés. La densité de B. aegyptiaca ne varie significativement entre sites et entre secteurs. Par contre, la densité de Z. mauritiana varie significativement entre sites et entre secteurs. En effet, le site de Birni Lallé, situé dans le secteur sahélien strict, et le site de Kegil dans le secteur sahélo-soudanien ont les densités les plus élevées de Z. mauritiana avec respectivement 66,4 ± 52,5 et 77,5 ± 61,4 arbres/ha. L’analyse de la distribution des tiges par classe de diamètre montre que pour les deux espèces, les individus jeunes sont bien représentés. Cela suggère une bonne régénération de ces espèces. L’analyse de la densité et nature de régénération montre que les deux espèces se régénèrent essentiellement par drageonnage. En réponse au ramassage des fruits pour diverses utilisations, les espèces B. aegyptiaca et Z. mauritiana ont développé des stratégies alternatives de propagation en zone sahélienne. Cette aptitude à la propagation végétative permet aux deux espèces de s’adapter en zones arides caractérisées par la sécheresse et les hautes températures. MOTS CLÉS : DISTRIBUTION DES ESPÈCES LIGNEUSES, B. AEGYPTIACA, Z. MAURITIANA, MARADI, NIGER, SAHÉLO-SOUDANIEN [83] afrika focus — Volume 33, Nr. 1, 2020 — pp. 83-104 RABIOU HABOU, MOUSSA MASSAOUDOU, TOUGIANI ABASSE, MAHAMANE ALI, MAHAMANE LARWANOU & PATRICK VAN DAMME Wood species play an important role in the life of local communities. Among the species commonly used in Niger, are Balanites aegyptiaca and Ziziphus mauritiana. This species are exploited as food sources and as various medicinal products, with a consequent reduction in their populations. The present study aims to analyze the stand structure and the regeneration modes of the two species in two contrasting agro-ecological sectors of the Maradi region in south central Niger. A total of 60 surveys were delineated in natural formations dominated by these species and in agrosilvopastoral system in the Sahelian and Sahelo-Sudanian zones. On each tree, the diameter at 1.30 m from the ground, the total height and two perpendicular tree crown diameters were measured. The inventory of natural regeneration was carried out in 5 plots delineated in each plot. The mode of reproduction of the regeneration (suckers, marcots, natural seedlings) was recorded as well as the total height and the number of stems of each juvenile were. The density of B. aegyptiaca does not vary significantly between sites and between sectors. The Birni Lallé site, located in the strict Sahelian zone, and the Kegil site in the Sahelo-Sudanese sector stand out in terms of Z. mauritiana density with respectively 66.4 ± 52.5 and 77.5 ± 61.4 trees. /Ha. The analysis of the diameter class structure shows that for both species, young individuals are well represented. This suggests strong regeneration among these species. The analysis of the density and nature of regeneration shows that the two species regenerate mainly by suckering. In response to the collection of fruits for various uses by local populations, B. aegyptiaca and Z. mauritiana have developed alternative propagation strategies in the Sahelian zone. This ability to propagate vegetatively allows these two species to adapt to arid areas characterized by drought and high temperatures. KEY WORDS: DISTRIBUTION OF WOODY SPECIES, B. AEGYPTIACA, Z. MAURITIANA, MARADI, NIGER, SAHELO-SUDANESE

Inorganic solid wastes from agrosilvopastoral sector in Ceres, Goiás, Brazil

This study aimed to verify the application of available legislation about to the production, quantity and appropriate disposal of inorganic solid wastes from agrosilvopastoral activities in Ceres/GO. The research had a descriptive character, with bibliographic, documentary and field research methods, based on quali-quantitative approaches, and the gathering of primary and secondary data. The data were extracted from official records and websites, including information of public and private institutions, and sourced by professional entities and associations responsible for collection, sorting, recycling and final disposal of solid wastes. On the basis of the obtained information, although Ceres/GO city has a small rural population, it was considered as good study model. The efforts and experiences carried out in Brazil and different countries gives us insights to understand and propose solutions related to the waste management from agrosilvopastoral system in Ceres/GO, which may be expanded into other Brazilian cities.

Influence of pastoral systems on Mahanarva spectabilis (Distant) (Hemiptera: Cercopidae) and the entomopathogen Metarhizium anisopliae (Metsch.) Sorokin

The influence of Urochloa brizantha (variety Marandu) grazing systems on Mahanarva spectabilis (Distant) and the entomopathogen Metarhizium anisopliae (Metsch.) was studied to understand the benefits of integrated systems in pest management. The pastoral systems studied were: (M) monoculture, (SP) silvopastoral and (ICLF). We assessed the number, per square meter, of alive spittlebug nymphs or infected by M. anisopliae as well as the demanded number of entomopathogen sprays in each pasture system to control the pest. Throughout the experiment period, M. spectabilis was the unique species found. Silvopastoral had a higher number of alive nymphs and a lower percentage of the infected nymphs compared to pasture in monoculture; however, in both systems, only one spray of M. anisopliae was enough to keep the pest below its threshold. In agrosilvopastoral system, there was no spittlebugs infestation, consequently, none sprays was demanded. Thus, intensified production systems such ICLF may be more sustainable, considering pest aspects.