Search

Trees play an important role in livestock grazing lands, but the effect of tree shade on grass productivity has not been studied widely. In this study, we evaluated the effect of tree shade on grass yield in pasturelands with dispersed trees in the humid tropics of Mexico. We sampled two livestock grazing systems: 1) scattered native trees in paddocks composed of Cordia alliodora and Cedrela odorata trees with Brachiaria brizantha cv. ‘Xaraes’ grass; and 2) scattered trees in paddocks composed of C. alliodora, C. odorata, and Guazuma ulmifolia, with B. brizantha cv. ‘Marandu’ grass. We established isolation cages at different distances from trees: 1) under the tree canopy, 2) on the border of the tree canopy, and 3) out of reach of the tree canopy, to measure grass yield, grass height, dry matter content, and senescent biomass from April to September. The effect of tree shade on grass yield was significant, with the highest grass production under the tree canopy compared with grasses that grew on the border of the tree canopy and in full sun. We found the highest forage yield in June for B. brizantha cv. Xaraes and the lowest yield in September for the same grass. During July and August, B. brizantha cv. Xaraes yielded the greatest average height, with the lowest values during April and May for B. brizantha cv. Marandu. The greatest dry matter content was recorded in September for B. brizantha cv. Xaraes. Additionally, the most senescent mass was recorded in June and the lowest in April for the same grass. Native trees that persist in grasslands positively influence forage yield during the dry season. Increasing the productivity of the grasslands by agroforestry practices may represent a valuable alternative to mitigate the negative effects of deforestation caused by extensive livestock farming.

We evaluated the effect of different dietary Tithonia diversifolia (TD: 0, 10, 20, and 30 %) on productive traits, egg quality, and economic efficiency in laying hens. Feed intake was higher in hens fed the 20 and 30 % TD diets (120.6 and 119.0 g/day) compared with those fed the 0 or 10 % TD diets (P < 0.0010). Feed egg weight conversion increased with dietary TD inclusion (P < 0.0010). The laying rate was higher (P < 0.0020) in hens on 0 and 10 % TD diets (94.5 and 94.6 %, respectively) than those on 20 and 30 % TD diets (89.7 and 84.9 %). Eggs and yolks were heavier in hens fed 0, 10, and 20 % TD compared with those fed the 30 % TD diet (P

Fire has been an integral part of ecosystem functioning in many biomes for a long time, but the increased intensity and frequency of wildfires often affect plant diversity and carbon storage. Prescribed burning is one of the alternatives to forest fuel management where the fire is controlled and carried out under a determined set of weather conditions and objectives. The effect of prescribed burning on plant diversity and carbon (C) storage has not been studied widely. The objective of this study was to evaluate the effect of prescribed burning on plant diversity indices, biomass stocks, and soil C storage in the tropical highland forests of Southern Mexico. We assessed plant diversity and carbon stocks at 21 sampling sites: seven with prescribed burning, seven non-burning, and seven with wildfires. We calculated tree biodiversity indices, stand structural properties, and species composition among burning treatments. We quantified C stocks in vegetation biomass by using an allometric equation and forest litter by direct sampling. We analyzed 252 soil samples for soil organic C content and other properties. The results showed that the biodiversity index was higher in sites with prescribed burning (Shannon index, H = 1.26) and non-burning (H = 1.14) than in wildfire sites (H = 0.36). There was a greater similarity in plant species composition between non-burning and prescribed burning sites compared to wildfire sites. Prescribed burning showed a positive effect on soil carbon storage (183.9 Mg C ha−1) when compared to wildfire (144.3 Mg C ha−1), but the difference was not statistically significant (p > 0.05) in biomass stocks. Prescribed burning in this study conserved plant diversity as well as soil carbon stocks compared to non-burning, the opposite of what we found in wildfires.

This study was carried out to evaluate the residual feed intake (RFI), volatile fatty acid (VFA) production and enteric methane (CH4) from growing Pelibuey sheep. In this case, 12 non-castrated Pelibuey with an initial average live weight (LW) of 21.17 ± 3.87 kg and an age of 3 months, were housed in individual pens and fed a basal diet with 16% of crude protein and 11 MJ ME for 45 days. Dry matter intake (DMI) was measured and the daily weight gain (DWG) was calculated using a linear regression between the LW and experimental period. Mean metabolic live weight (LW0.75) was calculated. RFI was determined by linear regression with DWG and LW0.75 as independent variables. Lambs were classified as low, medium, and high RFI. Feed efficiency was determined as DWG/DMI. For determining rumen pH, ammonia nitrogen concentration NH3-N), and VFA, ruminal fluid was obtained using an esophageal probe on day 40. Feed intake of low RFI lambs was approximately 16% lower (p < 0.05) while growth rate was not significantly different. Their average energy loss, expressed as CH4 production per kilogram of metabolic weight, was 17% lower (p < 0.05).

Understanding belowground morphological mechanisms of trees and grasses is a complicated task but can help in the design and management of silvopastoral systems. In this study, we evaluated the effect of the harvest intervals (i.e. 30 and 50 days) of aboveground biomass on the fine root density and vertical distribution in two silvopastoral systems (SPS): one comprising Leucaena leucocephala (legume tree) and Cynodon plectostachyus (grass) and the other L. leucocephala and Panicum maximum. We used a completely randomized design with four repetitions. We sampled fine roots by using a metal cylinder (8 cm diameter and 50 cm length) 7 days after each harvest. We washed the samples with pressurized water to separate them from the soil. The roots were digitalized at a resolution of 600 dpi to determine the diameter and specific root length by using IJ Rhizo® software. Samples were subsequently dried to quantify fine root mass. We found that the greater percentages of fine roots were between 0.4 and 0.8 mm for the legume and between 0.2 and 0.4 mm for grasses. The fine root length and mass density of P. maximum was higher (P 0.05). The effect of harvest interval was significant only in some soil layers in both SPS (P > 0.05). Most of the pasture roots were found in the upper soil layer (0–20 cm), while L. leucocephala roots were present to deeper soil layers. We conclude that P. maximum has a greater rooting capacity and a more rapid recovery than C. plectostachyus, which has greater diameters and lower root density. However, L. leucocephala presented deeper and thicker fine roots in both SPS, which is a good indication of its belowground recovery capacity to aboveground disturbances.

The tick Rhipicephalus microplus is known to develop resistance against some commercial acaracides, driving a search for natural alternatives. An evaluation was done of the acaricide activity against adult and larval R. microplus of ethanol extracts from three Leucaena spp. genotypes: L. leucocephala (Lam.) de Wit (Native); L. leucocephala (Cunningham); and L. Leucocephala x L. padilla (KX2). Larval immersion and adult immersion tests were used to evaluate acaricide activity. Secondary metabolite profiles of the three genotypes were generated using analytical chromatographic plates. Against the larvae, the 50% extract concentration exhibited 91.68% mortality for the Cunningham genotype, 82.00% for the KX2 and 54.06% for the Native. The Native genotype extract was most effective against adults with a 50% mortality at a 20% concentration. Flavonoids and terpenes were identified in all three genotypes and are probably responsible for their acaricide activity. The Leucaena spp. Cunningham and KX2 extracts were effective against R. microplus larvae, but further research is needed to identify the metabolites that provide this acaricide activity, be it individually or synergistically.

The objective of this study was to evaluate the effects of inclusion of tropical tree foliage on intake, digestibility, and nitrogen balance in sheep fed with a diet based on fresh chopped Pennisetum purpureum. Four male Pelibuey sheep were used, with an average live weight of 22 ± 1.5 kg, distributed in a (4 × 4) Latin square design. Treatments were P. purpureum (T1), P. purpureum + Brosimum alicastrum (T2), P. purpureum + Guazuma ulmifolia (T3), and P. purpureum + Piscidia piscipula (T4). Tree foliage was incorporated into the ration at a proportion rate of 300 g/kg of dry matter (DM). Intake, digestibility, and nitrogen balance were measured during 24 h periods for 7 days. DM intake, organic matter (OM), and crude protein (CP) intakes were not affected (P > 0.05) by including tree foliage (an average of 892.7, 784.2, and 88.9 g/day, respectively). OM and CP digestibility was similar among treatments (P > 0.05). Nevertheless, digestibility of DM and NDF was lower (P

The main constraints in the ruminant production systems in the tropics are low availability and quality of forage during the dry season. An alternative that could mitigate the lack of food during periods of scarcity is the use of trees/shrubs in fodder banks. However, the growth and production response of these plants may be influenced by several factors. The aim of the study was to evaluate the total height of plants, forage yield and crude protein (CP) concentration of Morus alba and Gliricidia sepium in mixed and pure fodder bank systems with three planting densities (i.e., 10,000, 13,333 and 20,000 plants ha−1). A completely randomized design with a 3 × 3 factorial arrangement was used, with four replicates per treatment. The total height of plants was similar among fodder banks. However, G. sepium and mixed fodder banks had a greater forage yield (5.48 and 5.50 t DM ha−1, respectively) and more CP concentration (20.07 and 20.41%, respectively) than M. alba fodder banks. There was no significant effect of planting densities on total height of plants, forage yield and CP concentration, in fodder bank systems. There was no significant effect of interaction between fodder banks and planting densities on total height of plants and forage yield. However, the CP concentration was greater in the M. alba and mixed fodder banks in three planting densities, together with G. sepium fodder bank in a density of 10,000 plants ha−1, compared to G. sepium fodder banks at planting densities of 13,333 and 20,000 plants ha−1. We conclude that the mixed fodder bank of M. alba and G. sepium can increase the production and forage quality of the system.

In dairy production systems, the efficient use of resources is required to guarantee its sustainability. Worldwide, the efficiency of feed utilization and its effects have been widely studied. However, few studies have quantified animal nitrogen use and its corresponding soil contribution in small-scale production systems. Therefore, this study aimed to determine the efficiency of feed utilization and quantify the soil chemical composition in small-scale production systems using two different feeding strategies. Twelve dairy farms were evaluated from May 2016 to April 2017. Data analysis was performed using an ANOVA following a completely randomized model and using feeding strategies as treatment. Regarding the feeding systems’ characteristics, significant differences (P

Aethina tumida, es una plaga de Apis mellifera L. (Hymenoptera: Apidae) responsable de pérdidas económicas en la producción de miel. En México no existe un producto autorizado para su control, razón por el cual, el objetivo fue evaluar el efecto tóxico de Dysphania ambrosioides L., Ocimum basilicum L. y Origanum vulgare L., bajo un diseño completamente al azar. Los tres polvos presentaron efecto tóxico contra adultos de A. tumida. D. ambrosioides registro un mejor efecto, siendo estadísticamente diferente al resto de los tratamientos (P ? 0.05), demostrando el 100% de mortalidad con 1, 5 y 10 g después de 24 o 48 h del tratamiento, no así para los tratamientos a base de O. basilicum y O. vulgare, donde la dosis y el tiempo jugaron un papel importante, ambos demostraron su mayor efectividad (69.2 y 65.8% respectivamente) con la dosis de 10 g a las 48 h posteriores al tratamiento.

Simple Summary Methane produced by enteric fermentation contributes to the emission of greenhouse gases (GHG) into the atmosphere. Methane is one of the GHG arising from anthropogenic activities with the greater contribution to global warming. This paper provides a brief introduction to the potential use of tropical foliage trees, pods, and secondary metabolites to reduce methane emissions from ruminant supply chains. A better knowledge of the available strategies for efficient foliage use in the tropics is essential in order to ensure increasing livestock production while preserving the environment. The mitigation of rumen methane production through the use of the foliage and metabolites of tropical trees represents an interesting challenge for scientists working in the field of ruminant nutrition. Abstract Methane produced by enteric fermentation contributes to the emission of greenhouse gases (GHG) into the atmosphere. Methane is one of the GHG resulting from anthropogenic activities with the greater global warming contribution. Ruminant production systems contribute between 18% and 33% of methane emissions. Due to this, there has been growing interest in finding feed alternatives which may help to mitigate methane production in the rumen. The presence of a vast range of secondary metabolites in tropical trees (coumarins, phenols, tannins, and saponins, among others) may be a valuable alternative to manipulate rumen fermentation and partially defaunate the rumen, and thus reduce enteric methane production. Recent reports suggest that it is possible to decrease methane emissions in sheep by up to 27% by feeding them saponins from the tea leaves of Camellia sinensis; partial defaunation (54%) of the rumen has been achieved using saponins from Sapindus saponaria. The aim of this review was to collect, analyze, and interpret scientific information on the potential of tropical trees and their secondary metabolites to mitigate methane emissions from ruminants.

The study aimed to evaluate the relationship between udder measurements and milk yield (MY) in dairy Pelibuey ewes. Udder measurements were taken twice a week for eight weeks before (initial) and after (final) milking, including udder depth (UD), udder circumference (UC), udder width (UW), teat length (TL) and teat diameter (TD) in 38 multiparous ewes. Additionally, udder volume (UV) and the difference (VDF) between initial UV (UVi) and final (UVf) was calculated as VDF = UVi &minus, UVf. The MY varied from 0.10 kg/d to 1.04 kg/d, with a mean of 0.39 kg/d, &plusmn, 0.18 kg/d. Initial UC (UCi) ranged from 25.80 cm to 53.30 cm, and VDF varied from 1 cm3 to 2418 cm3. The TL and TD were not correlated with MY (p &gt, 0.05), while UCi, UVi and VDF were positively correlated with MY (p &lt, 0.0001, r = from 0.66 to 0.74). For the prediction of MY, the obtained equations had an r2 ranging from 0.54 to 0.63. The UCi, UDf, UWi and UWf were included in these models (p &lt, 0.05). It is concluded that there was an acceptable correlation (r = 0.60) between the measurements of the udder, the volume of the udder and the daily milk yield in Pelibuey sheep. When direct measurements of milk production cannot be performed in practice, the measurement of udders and their volume could be a viable alternative to estimate milk yield production as an indirect method.

In Mexico, extensive production systems have caused a drastic reduction in tropical forests and in biological diversity. Most of the agroforestry systems (AFS) in Mexico use leguminous species that naturally associate with arbuscular mycorrhiza fungi (AMF) and bacterial nitrogen fixing that aid the uptake of N and P in poor soils of the tropics. The AMF and bacteria are predominant in tropical agroecosystems with wide ranges of hosts with potential to increase growth in forest species and in crop yield. Mexico is considered one of the countries with high diversity of plants within the countries of America with potentially high number of AMF species and bacteria in different SAF. Although we have considerable knowledge of the plants used in different AFS, the richness of soil microorganisms has received little attention in Mexico’s tropics. Understanding of the structure and functional diversity of AMF and bacteria have allowed us to generate the bases for a sustainable AFS, increasing productivity and, at the same time, AFS work as reservoirs and biological corridors that could reduce degradation of forests.

Livestock production in the tropics contributes significantly to global greenhouse gas emissions, so better understanding the role of silvopastoral systems (SPS) in mitigating such emissions is necessary. The aim of this study was to evaluate the amounts of carbon stored in the biomass and soil organic carbon (SOC) components of a Leucaena leucocephala cum Panicum maximum silvopasture system (SPS) compared to a deciduous tropical forest (DTF), and a grass monoculture (GM) in Michoacan, Mexico. The above- and below-ground biomass were measured by destructive sampling in the SPS and GM, while previously reported allometric equations were used to quantify biomass stocks in the DTF. The SOC concentration up to 30 cm was determined by dry combustion method. The SPS and DTF contained more aboveground biomass (41.8 ± 3.30 and 36.7 ± 5.72 Mg DM ha−1) compared to GM (8.0 ± 0.76 Mg DM ha−1). However, the SPS exhibited greater belowground biomass (16.4 ± 1.95 Mg DM ha−1) than the other systems. The DTF had the highest SOC fraction in all depth classes with values ranging from 3.1 ± 0.07% to 3.7 ± 0.06%, respectively, compared to the other systems. The total carbon stocks in SPS was similar to DTF (120.7 ± 10.97 vs. 120.9 ± 6.38 Mg C ha−1) but was significantly higher than GM (78.2 ± 8.41 Mg C ha−1). In dry tropical conditions, SPS displays enormous potential for increasing biomass and soil carbon stocks compared to the GM and can thus be used as a greenhouse gas mitigation strategy in livestock production systems.

En Mexico, la apicultura es una de las principales actividades del sector agropecuario debido a su produccion de miel de alta calidad la cual es apreciada en diversos paises de Europa. Esta actividad es practicada por mas de 40000 productores, que cuentan con alrededor de dos millones de colmenas en apiarios distribuidos en las cinco regiones apicolas a nivel nacional (Norte, Centro y Altiplano, Pacifico, Golfo y Peninsula de Yucatan). La peninsula de Yucatan incluye los estados de Campeche, Yucatan y Quintana Roo, considerada como la region mas importante debido a que destina cerca del 95 % de la produccion de miel al mercado internacional. La region concentra del 30 al 35 % del total de las colonias de abejas a nivel nacional y es considerada como una actividad secundaria. Con la finalidad de caracterizar la actividad apicola en Campeche (en municipios de Campeche, Champoton y Hopelchen), se aplicaron encuestas a 120 productores de julio a diciembre del 2016. La edad promedio de los apicultores fue de 57 anos, con un promedio de 2.27 apiarios por productor, con 20.6 colmenas por apiario. Los apicultores dedican dos dias a la semana a esta actividad y realizan en promedio 3.67 cosechas por ano. Con base en lo anterior, se recomienda fomentar el relevo generacional en la actividad apicola, que se enfoque en jovenes apicultores.

The objective was to evaluate the production and nutritional composition of cassava (Manihot esculenta Crantz) meal under dierent organic fertilization rates. Twenty 10 10 m plots were planted with cassava and fertilized with 0.0, 0.5, 1.0 and 1.5 kg plant-1 of sugarcane lter cake (part of the waste left after processing). The variables measured were fresh and dry forage yield (FFY and DFY), fresh and dry tuber yield (FTY and DTY), meal yield (MY) and their nutritional composition. The results indicate that the organic fertilization signicantly increased the FFY, DFY, FTY, DTY and MY compared to the control. Applying 1.5 kg of organic fertilizer signicantly improved crude protein content (CP, 3.37%). Organic fertilization with 1.5 kg plant-1 of compost improved forage and tuber yield, and CP content.

The rapid deforestation in the state of Tabasco due to extensive livestock farming has resulted in the decrease of the original forest cover. Only 4% of the original vegetation remains and that vegetation is concentrated in the mountainous regions of the state. This destructive process continues due to support by the current government livestock policies. Under these circumstances, the traditional silvopastoral systems of dispersed trees can present an option for reversing and mitigating deforestation practices. The objective of this study was to generate information on the tree species common to silvopastoral systems of dispersed trees in the pastures for two mountainous areas in Tabasco. In the study, 64 tree species, representing 26 plant families were identified. All species were characterized as multipurpose, with at least three reported uses and a maximum of seven for each species. In total, nine categories of local uses were identified for the trees. The main category of use was fuel (firewood), followed by timber and shade for the livestock. Although leguminous species (Fabaceae) were dominant, these species were utilized for uses other than the provision of fodder. Since 12 of the total species identified were recognized as sources of food for animals; the assumption that livestock farmers do not recognize the utility of these species for improving production yields is apparent. The results suggest that there is potential need to expand research and offer further education on the subject in Tabasco.

Las poblaciones endemicas de Abies religiosa (abeto, oyamel) poseen gran importancia economica, ecologica y social; ademas, forman distintas interacciones con microorganismos edaficos, principalmente con hongos ectomicorrizogenos. Actualmente, las poblaciones aisladas (i. e. oyamel) estan amenazadas por la deforestacion, la expansion agricola y el calentamiento global; por lo cual, es urgente entender las interacciones ecologicas y evolutivas con hongos ectomicorrizogenos. El objetivo de la presente investigacion fue analizar el uso de la ecologia, taxonomia y biologia molecular de ectomicorrizas para comprender el papel que juegan estos hongos en arboles de A. religiosa en Mexico. Se presentan areas de oportunidad de investigacion, asi como los principales vacios de informacion de la caracterizacion morfoanatomica/molecular, taxonomia y evolucion de la simbiosis ectomicorrizica en bosques de A. religiosa. Para lo anterior, se reunio informacion de 108 taxa de hongos potencialmente ectomicorrizogenos, colectados en diferentes poblaciones de abetos. Los taxa con potencial alto para inocular A. religiosa son Sebacina dimitica, Clavulina cf. cinerea, Membranomyces sp., Thelephoraceae, Russula spp., Ramaria spp., Lactarius spp. e Inocybe spp. Finalmente, se discuten aspectos que faltan por resolver para determinar su potencial de uso, manejo, conservacion y aprovechamiento de A. religiosa en zonas templadas de Mexico. Este problema puede resolverse combinando herramientas moleculares con la descripcion morfologica e histologica de morfotipos ectomicorrizogenos. Adicionalmente, se requieren metodologias que permitan estandarizar resultados para llegar a conclusiones mas solidas sobre las interacciones micorrizicas.

The aim of this study was to assess the effect of the inclusion of Leucaena leucocephala on dry matter (DM) intake and digestibility, nitrogen (N) balance and energy utilization in cattle fed a basal ration of Pennisetum purpureum and housed in metabolic crates. Five crossbred ( Bos taurus × Bos indicus ) heifers (BW: 295 ± 6 kg) were fed chopped P. purpureum grass and five increasing levels of L. leucocephala (0, 20, 40, 60 and 80% of DM) in a 5 × 5 Latin square design. The intake of DM was similar (P > 0.05) among treatments, with an average of 7.03 kg of DM/day. While the crude protein intake (CPI) linearly increased (P L. leucocephala , the DM digestibility (average 492.3 g/kg DM) and OM digestibility (average 501.6 g/kg OM) were not affected (P > 0.05) by the incorporation of L. leucocephala into the ration. The N intake and excretion in the urine increased linearly (P = 0.0001, 0.0001) as the level of L. leucocephala in the ration increased. In addition, methane energy loss as a percentage of that in the control ration, was of only 61% (P = 0.0005) with 80% incorporation of L. leucocephala in the ration. We concluded that the inclusion of L. leucocephala has the capacity to reduce energy losses in the form of methane emissions. Nevertheless, the energy losses in the urine increased with the addition of L. leucocephala to the ration, with the optimal levels of incorporation in the ration fluctuating between 20 and 40% of the ration DM, which had no effects on the dry matter intake (DMI), organic matter intake (OMI) or the digestibility of dry matter (DMD).

Introduction: The diversity of macro-arthropods is related to the state of disturbance of the soil, caused mainly by the change of land use for agricultural activities. A strategy for the conservation of these organisms is the implementation of diversified production systems such as silvopastoral systems, however; In the southeast of Mexico, information is still limited. Objective: The aim of the present study was to evaluate and compare the richness, abundance of macro-arthropods in four contrasting agro-ecosystems: two silvopastoral systems made of Leucaena leucocephalaand associated pastures (i.e. Panicum maximumcv mombaza and Cynodon plectostachyus), a pasture of Brachiaria brizanthawith scattered trees in low density and, a medium-stature forest. Methods: For this, the pit-fall traps were used, which consisted of plastic containers of one liter capacity and a diameter of 14.4 cm. The samplings were made in two periods: one in the month of February and another in the month of May 2018, in each month there were five spaced collections, which made a total of 100 samples. Results: A total of 1 737 organisms belonging to 14 species of 11 genera were collected. The systems with the greater abundance of macro-arthropods were the system of medium-stature forest (923 individuals) and the silvopastoral system of L. leucocephalawith C. plectostachyus(354 individuals). The most abundant genera were: Hymenoptera, Coleoptera, Aracnidos and Orthoptera. The greatest diversity of macro-arthropods occurred in the silvopastoral systems of L. leucocephalawith P. maximum(H '= 1.586) and L. leucocephalawith C. plectostachyus(H' = 1.441). Conclusions: The results show that livestock systems managed with woody components (trees or shrubs) can be equated, in terms of abundance and diversity of macro-arthropods, with systems such as tropical forests, which contributes to the integrity and functionality of the agro-ecosystems. Introducción: La diversidad de macro-artrópodos está relacionada con el estado de conservación del suelo, por lo tanto, el cambio de uso del suelo afecta su integridad. Una estrategia para la conservación de estos organismos es la implementación de sistemas de producción diversificados como los sistemas silvopastoriles; no obstante, en el sureste de México la información aún es limitada. Objetivo: El propósito del presente estudio fue evaluar y comparar la riqueza y la abundancia de macro-artrópodos en cuatro agro-ecosistemas contrastantes: dos sistemas silvopastoriles conformados por Leucaena leucocephalay pastos asociados (i.e. Panicum maximumcv mombaza y Cynodon plectostachyus), un pastizal convencional de Brachiaria brizanthacon árboles dispersos y una selva mediana subperennifolia. Métodos: Se utilizaron trampas pit-fall de un litro de capacidad y un diámetro de 14.4 cm. Los muestreos se realizaron en dos periodos: uno en el mes de febrero y otro en el mes de mayo del 2018, en cada mes se hicieron cinco colectas espaciadas, lo que hizo un total de 100 muestras. Resultados: Se recolectaron un total de 1 737 organismos pertenecientes a 14 especies de 11 órdenes. Los sistemas con mayor abundancia de macro-artrópodos fueron, el sistema de selva media subperennifolia (923 individuos) y el sistema silvopastoril de L. leucocephalacon C. plectostachyus(354 individuos). Los órdenes más abundantes fueron: Hymenoptera, Coleoptera, Aracnidos y Orthoptera.La mayor diversidad de macro-artrópodos se presentó en los sistemas silvopastoriles de L. leucocephalacon P. maximum(H’=1.586) y L. leucocephalacon C. plectostachyus(H´=1.441). Conclusiones: Los resultados encontrados muestran que los sistemas pecuarios manejados con componentes leñosos (árboles/arbustos) pueden equipararse, en términos de abundancia y diversidad de órdenes de macro-artrópodos, con sistemas como las selvas o bosques, lo cual contribuye a la integridad y funcionalidad de los agro-ecosistemas.

The aim of the present study was to develop and evaluate an equation to predict body weight (BW) using hip width (HW) in Pelibuey ewe lambs and ewes. Five hundred seventy-seven 2-month-old to 3-year-old, non-pregnant, non-lactating, clinically healthy ewe lambs and adult ewes with a mean BW of 34.7 ± 12.4 kg and HW of 15.6 ± 3.4 cm were considered. Three equations were evaluated: BW (kg): − 19.17 + 3.46 × HW (Eq. 1), BW (kg): − 17.79 + 3.25 × HW + 0.007 × HW2 (Eq. 2) and BW (kg): 0.39 × HW1.63 (Eq. 3). Independent data from 80 animals with similar characteristics (BW of 23.4 ± 10.9 kg and HW of 12 ± 3.1 cm) were also considered to evaluate the developed equations. The evaluation was based on the relationship between the observed and predicted values of BW analysed using a linear regression, the mean squared error of prediction (MSEP), the root MSEP (RMSEP) and the concordance correlation coefficients (CCCs). Additionally, cross-validation analyses were performed using the k-folds validation (k = 10) procedure. The correlation coefficient (r) between BW and HW was 0.94 (P 0.95%), accuracy (Cb > 0.98) and reproducibility (CCC > 0.96) in predicting the BW of ewe lambs and adult ewes. Equation (1) accurately predicted observed BW, with a bias (observed − predicted) of 4.3 kg and RMSEP of 9.68% with respect to the observed BW (random error of 84.23%); it also generated the best prediction according to the residual mean squared prediction error, coefficient of determination and mean absolute error. In conclusion, the highly correlated relationship between BW and HW in Pelibuey ewe lambs and adult ewes under humid tropic conditions enabled the development of mathematical models herein to estimate BW with an adequate goodness of fit. The linear model showed the best performance according to the goodness-of-fit evaluation and internal and external validation; hence, this model is proposed for use in both the experimental and commercial farms.