Producción de materia seca y componentes morfológicos de cuatro cultivares de Brachiaria en el trópico

El objetivo fue evaluar bajo condiciones de temporal la adaptación de cuatro cultivares de Brachiaria, con base en su comportamiento agronómico a diferentes edades de corte. Las variables medidas fueron: altura, producción de hojas, tallos, total, material vivo y muerto. Los datos se analizaron en diseño de bloques al azar con arreglo en parcelas divididas y prueba de Tukey, P<0.05, para diferencia múltiple de medias. La altura fue mayor (P<0.001) en los cultivares B. brizantha (Mg4) e Híbrido Mulato, con 42 y 41 cm, respectivamente, con relación a B. brizantha. La producción de hoja y material vivo fue mayor en el Híbrido Mulato, con 688 kg ms ha-1 (P<0.006) y 1,104 ms ha-1; P<0.001), respectivamente, comparada con B. decumbens. La producción de tallos (457 kg ms ha-1; P=0.05) y materia seca total (1,125 ms ha-1; P=0.05), tuvo tendencia a ser mayor en Híbrido Mulato. Se concluye que los cultivares con mejor desempeño agronómico fueron Brachiaria ruziziensis X B. brizantha (Híbrido Mulato) y Mg4, sin diferencia en la producción de materia seca entre cultivares

IDENTIFICACIÓN, USOS Y MEDICIÓN DE LEGUMINOSAS ARBÓREAS FORRAJERAS EN RANCHOS GANADEROS DEL SUR DEL ESTADO DE MÉXICO

El objetivo del trabajo fue identificar las especies arbóreas leguminosas, usos, densidad, frecuencia, abundancia y medidas dasométricas en ranchos ganaderos del sur del Estado de México; así como evaluar la producción de follaje (kg materia seca árbol-1ha-1) de Pithecellobium dulce, Haematoxylum brasiletto y Gliricidia sepium -preferidas por los ganaderos como fuente de forraje y con mayor densidad-; y evaluar la producción de fruto (kg materia seca árbol-1ha-1) de Acacia cochliacantha y P. dulce. La información de usos se obtuvo mediante entrevistas semiestructuradas aplicadas a 69 ganaderos, cantidad que representó 83% de la población. Las mediciones de los árboles se realizaron en seis ranchos mediante trabajo de campo. La información se analizó usando estadísticas descriptivas. Se identificaron 12 especies arbóreas (Acacia cochliacantha, Lysiloma divaricata, Pithecellobium dulce, Haematoxylum brasiletto y Gliricidia sepium), las cuales presentaron mayor densidad, frecuencia y abundancia. De 46.6% de las arbóreas, su follaje y fruto es consumido por rumiantes; de 20%, es consumido follaje, fruto y flor. Se proporcionan de cinco a ocho usos en 80% de las especies, además del forrajero, como leña, poste, sombra, cerca viva, medicinal, consumo humano, artesanal y maderable. Las arbóreas con mayor fuste fueron: Caesalpinia coriaria, Pithecellobium dulce, Enterolobium cyclocarpum y Leucaena esculenta, con diámetro basal (DB) de 47.11 a 57.2 cm, diámetro a la altura del pecho (DAP) de 49.34 a 50.3 cm y altura (A) de 7.4 a 14.5 m, los cuales son preferidos para sombra. La producción de follaje de Pithecellobium dulce, Haematoxylum brasiletto y Gliricidia sepium fue de 44.5, 8.8 y 8.4 kg MS arbol-1, respectivamente. La producción de fruto de Pithecellobium dulce y Acacia cochliacantha fue 63.9 y 21.7 kg MS árbol-1, respectivamente. Las 12 leguminosas arbóreas identificadas en la zona son reconocidas por los productores como arbóreas multipropósito, cuyo follaje es fuente de alimento para el ganado en lluvias y el fruto en secas, por lo que es importante su conservación y manejo en los ranchos ganaderos

Productive response of lambs fed Crescentia alata and Guazuma ulmifolia fruits in a tropical region of Mexico

polyethylene glycol (PEG) of the fruits of Crescentia alata and Guazuma ulmifolia was evaluated, the degradation kinetics of lamb diets with added fruit of the tree was determined, and the ration intake and growth rate of lambs fed these diets were measured. Twenty-five entire male lambs of 23.5± 0.44 kg body weight were used and distributed in treatments: T0 (control without fruit); T1 and T2, 15 and 30 % of the fruit of C. alata; and T3 and T4, 15 and 30 % of the fruit of G. ulmifoli

Influence of Salix babylonica extract addition on in vitro rumen gas production and degradability of ryegrass silage harvested in different cutting days

Four cutoffs of ryegrass after 15 days (CD15), 30 days (CD30), 45 days (CD45), and 60 days (CD60) with Salix babylonica (SB) extract at 0, 30, and 60 ml/kg ryegrass silage were ensiled for 40 days and then evaluated for the in vitro dry matter (DM) digestibility and gas production (GP). No interactions occurred between cutting day and SB extract for silage’s nutrient contents and in vitro GP. The DM and organic matter (OM) contents were decreased linearly with decreased crude protein (CP), neutral detergent fibres, acid detergent fibres, and acid detergent lignin contents with advancing of days. In contrary, addition of SB extract increased silages’ OM and decreased CP contents. Addition of SB extract for CD15 and CD60 silages, quadratically decreased the lag time. However, SB extract increased the rate of GP and GP during the first 12 h of incubation at the level of 30 ml/kg with CD30 silage and asymptotic GP with the level 60 ml/kg of CD60 silage. Increased DM degradability (DMD) of CD30 and CD60 silages versus decreased DMD with CD15 with increased relative GP (ml gas/g DMD). It could be concluded that CD15 had the highest DM and OM content; however, higher GP was noted with CD45 and CD60. SB extract had weak effects on nutrient content and GP, and the level of 30 ml/kg DM was more effective than the level of 60 ml/kg DM

The chemical composition and in vitro digestibility evaluation of almond tree (Prunus dulcis D. A. Webb syn. Prunus amygdalus; var. Shokoufeh) leaves versus hulls and green versus dry leaves as feed for ruminants

The current study aimed to evaluate the chemical composition and in vitro digestibility of almond tree (Prunus dulcis D. A. Webb syn. Prunus amygdalus; var. Shokoufeh) leaves versus hulls, and green versus dry leaves as feed for ruminants. The fresh green almond hulls (GAH) and leaves (GAL) were harvested and spread under a shade to dry. Dry almond leaves (DAL) were collected from under the trees where as dry almond hulls (DAH) were collected 4 weeks after harvesting the fresh samples. The chemical composition of substrates was determined using standard approaches and the metabolisable energy (ME), in vitro dry matter (DMD) and in vitro organic matter (OMD) digestibility were measured using the in vitro gas production (GP) technique. The GAL contained 81 g crude protein (CP) kg-1 DM while DAH contained 103 g CP kg-1 DM. The CP was higher (P = 0.0003) in dry (leaves and hulls) than in green (leaves and hulls) samples. The ash content ranged from 99.2 to 181.5 g kg-1 DM in DAH and DAL, respectively, (P = 0.0041). The ether extract content ranged from 27 for DAH to 65 g kg-1 for DAL (P = 0.0018). The acid detergent fibre and neutral detergent fibre content ranged from 185 to 304 and 444 to 620 g kg-1 DM (P = 0.04), for GAL and DAH, respectively. The DAH had the highest (P = 0.0001) GP24 and GP96. The DAH had the highest (P = 0.0001) potential GP (i.e., b), while the GP rate was highest for GAL and GAH (P = 0.034), ME was highest for DAH (P = 0.0001), and in vitro OMD was highest for DAH (P = 0.0001). The highest DMD (P = 0.0001) values were obtained with DAH followed by GAL, DAL and GAH, respectively. It can be concluded that almond hulls and leaves have a good nutritional potential to cover the maintenance nutrient requirements of small ruminants. Almond hulls and leaves can also be used as supplement to low quality mature pasture and/or crop residues. However, more studies are warranted to better characterize these feeds in in vivo animal feeding trials

Influence of oral administration of Salix babylonica extract on milk production and composition in dairy cows

Ruminal fermentation is accompanied by losses of the energy and protein consumed by dairy cows (Tamminga, 1992; Busquet et al., 2006) which may limit productive performance and contribute to release of pollutants to the environment (Calsamiglia et al., 2007). Ionophores have been used to reduce these losses (McGuffey et al., 2001), but the use of antibiotics in animal feeds has been banned in the European Union since January 2006 (Jiménez-Peralta et al., 2012) due to potential appearance of residues in milk (Russell and Houlihan, 2003). For this reason, there is substantial interest in evaluating the potential of using natural antimicrobials, such as plant extracts generally recognized as safe for human consumption (Busquet et al., 2006; Fandiño et al., 2008), to modify rumen microbial fermentation. Extract of Salix babylonica (SB) have been evaluated for their anti-microbial effects and for their potential to modulate ruminal fermentation and improve nutrient utilization in ruminants (Mejía-Hernández et al., 2013; Salem, 2012; Salem et al., 2010, 2011).The antimicrobial activity of SB extracts has been attributed to a number of plant secondary metabolites (PSM) such as alkaloids, saponins and phenolics (Jiménez-Peralta et al., 2011). Rumen microorganisms have the ability to degrade low concentrations of PSM without negative effects on rumen fermentation. Rumen microorganisms can also degrade alkaloids (Lanigan, 1970; Wachenheim et al., 1992), saponins (Lu and Jorgensen, 1987; Hu et al., 2005; Hart et al., 2008) and phenolics (Varel and Jung, 1986; Varel et al., 1991) and utilize them as an energy source. Some PSM can enhance protein metabolism and decrease methane production (Benchaar et al., 2007), and have the ability to suppress or stimulate microbial growth, increase binding of ammonia during urea ammoniation of straw and reduce odours from cattle manure in dairy barns (Makkar et al., 1998; Salem et al., 2012). In addition, some PSM reduce nutritional stress such as bloat and/or improve animal health and productivity (Patra et al., 2006; Benchaar et al., 2007, Xhomfulana et al., 2009; Salem et al., 2010). Positive effects on daily gain, voluntary feed intake and milk production (Salem et al., 2011) have been demonstrated, as well as a protective effect on dietary protein in the rumen in order to promote duodenal absorption, minimize excretion of nitrogen, modify the acetate to propionate ratio in rumen fluid and decrease the parasitic load (Salem et al., 2010; Jiménez- Peralta et al., 2011). Use of plant extracts could be limited by their secondary compound concentrations as consumption of large amounts of tannins or saponins may have a direct haemolytic effect and may even cause death (Athanasiadou and Kyriazakis, 2004). Moreover, long term feeding of plants rich in secondary compounds may have detrimental effects on animal health (Mahgoub et al., 2008). This experiment was conducted to determine effects of SB extract mixed in the diet on milk production and composition in Brown Swiss cows in addition to in vitro gas production of the diet fed to the cows with different doses of SB.A 3×3 Latin Square design was used to evaluate effects of 0, 150 and 300 mL of Salix babylonica (SB) extract mixed into the diet on daily milk production and composition in cows. Three Brown Swiss dairy cows (420±30.3 kg body weight), at late lactation (220±25.1 d in milk), were fed a diet with a restricted amount of concentrate and oat hay ad libitum twice daily in equal amounts. The SB extract was mixed daily with a small amount of concentrate and fed to the cows. In vitro gas production of the diet fed to the cows was recorded at 2, 4, 6, 8, 10, 12, 24, 48, and 72 h of incubation with 0, 0.6, 1.2 and 1.8 mL SB/g DM

The chemical composition and in vitro digestibility evaluation of almond tree (Prunus dulcis D. A. Webb syn. Prunus amygdalus; var. Shokoufeh) leaves versus hulls and green versus dry leaves as feed for ruminants

Almond, (Prunus dulcis D. A. Webb syn. Prunus amygdalus) is a species belonging to the Rosaceae family (Sfahlan et al. 2009). The state of California in the USA is the major producer of almond; however, its production is widely distributed (Wijerante et al. 2006) and there is increasing interest to produce almond and its by-products worldwide. Approximately 2,112,815 metric ton of almonds with shell is produced globally with Iran contributing about 110,000 metric ton (FAO 2007). Almond is a midsize tree with fruit that can grow up to ten meters tall (Chen et al. 2010). The fruit is made of hulls, shell and kernel. Drying almond hulls results in approximately (kg-1 DM) 250 g nut, 500 g hulls and 250 g shell (Aguilar et al. 1984; Fadel 1999).The current study aimed to evaluate the chemical composition and in vitro digestibility of almond tree (Prunus dulcis D. A. Webb syn. Prunus amygdalus; var. Shokoufeh) leaves versus hulls, and green versus dry leaves as feed for ruminants. The fresh green almond hulls (GAH) and leaves (GAL) were harvested and spread under a shade to dry. Dry almond leaves (DAL) were collected from under the trees where as dry almond hulls (DAH) were collected 4 weeks after harvesting the fresh samples. The chemical composition of substrates was determined using standard approaches and the metabolisable energy (ME), in vitro dry matter (DMD) and in vitro organic matter (OMD) digestibility were measured using the in vitro gas production (GP) technique. The GAL contained 81 g crude protein (CP) kg-1 DM while DAH contained 103 g CP kg-1 DM. The CP was higher (P = 0.0003) in dry (leaves and hulls) than in green (leaves and hulls) samples. The ash content ranged from 99.2 to 181.5 g kg-1 DM in DAH and DAL, respectively, (P = 0.0041). The ether extract content ranged from 27 for DAH to 65 g kg-1 for DAL (P = 0.0018). The acid detergent fibre and neutral detergent fibre content ranged from 185 to 304 and 444 to 620 g kg-1 DM (P = 0.04), for GAL and DAH, respectively. The DAH had the highest (P = 0.0001) GP24 and GP96. The DAH had the highest (P = 0.0001) potential GP (i.e., b), while the GP rate was highest for GAL and GAH (P = 0.034), ME was highest for DAH (P = 0.0001), and in vitro OMD was highest for DAH (P = 0.0001). The highest DMD (P = 0.0001) values were obtained with DAH followed by GAL, DAL and GAH, respectively. It can be concluded that almond hulls and leaves have a good nutritional potential to cover the maintenance nutrient requirements of small ruminants. Almond hulls and leaves can also be used as supplement to low quality mature pasture and/or crop residues. However, more studies are warranted to better characterize these feeds in in vivo animal feeding trials

Effect of polyethylene glycol on in vitro gas production of some non-leguminous forage trees in tropical region of the south of Mexico

The aim of this study was to evaluate the chemical composition of five foliages, and the effect of adding PEG during incubation on in vitro gas production (GP), metabolizable energy (ME), partitioning factor (PF24h), in vitro organic matter digestibility (OMD), short chain fatty acids (SCFA) and microbial biomass production (MBP) as tools to detect the adverse effect of tannins in the foliage of non-leguminous trees.The objective of the current study was to evaluate the chemical composition and the in vitro gas production (GP) of some non-leguminous forage trees in presence or absence of polyethylene glycol (PEG). Guazuma ulmifolia, Crescentia alata, Ficus glabrata, Ficus cotinifolia, Spondias purpurea, Mangifera indica, Licania arborea, Simira mexicana were collected during the rainy season, in the Bejucos locality, State of Mexico. Metabolizable energy (ME), partitioning factor (PF24h), in vitro organic matter digestibility (OMD), short chain fatty acids (SCFA) and microbial biomass production (MBP) were estimated as tools to detect the adverse effects of tannins in tree foliage. The chemical composition data were analyzed in a random design, and the in vitro digestion parameters on a randomized design with 8 9 2 factorial arrangement. Chemical composition showed a wide variation (P\0.05) between species. The use of PEG increased (P\0.05) GP from the foliage of S. purpurea, L. arborea, F. glabrata and G. ulmifolia, showing activity of total phenolics and condensed tannins. Similarly, ME (5.9 MJ kg-1 DM), OMD (354.5 g kg-1 DM) and SCFA (2.3 mol/150 mL) increased (P\0.05); it was higher for S. purpurea, because of the PEG addition effect. The PF24h and MBP were different between species (P\0.05), and decreased due to PEG addition (P\0.05); the species with lower production was S. purpurea. It could be concluded that S. purpurea and F. cotinifolia represent important sources of fodder for livestock in the south region of Mexico

A real use case of semi-supervised learning for mammogram classification in a local clinic of Costa Rica

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.The implementation of deep learning-based computer-aided diagnosis systems for the classification of mammogram images can help in improving the accuracy, reliability, and cost of diagnosing patients. However, training a deep learning model requires a considerable amount of labelled images, which can be expensive to obtain as time and effort from clinical practitioners are required. To address this, a number of publicly available datasets have been built with data from different hospitals and clinics, which can be used to pre-train the model. However, using models trained on these datasets for later transfer learning and model fine-tuning with images sampled from a different hospital or clinic might result in lower performance. This is due to the distribution mismatch of the datasets, which include different patient populations and image acquisition protocols. In this work, a real-world scenario is evaluated where a novel target dataset sampled from a private Costa Rican clinic is used, with few labels and heavily imbalanced data. The use of two popular and publicly available datasets (INbreast and CBIS-DDSM) as source data, to train and test the models on the novel target dataset, is evaluated. A common approach to further improve the model’s performance under such small labelled target dataset setting is data augmentation. However, often cheaper unlabelled data is available from the target clinic. Therefore, semi-supervised deep learning, which leverages both labelled and unlabelled data, can be used in such conditions. In this work, we evaluate the semi-supervised deep learning approach known as MixMatch, to take advantage of unlabelled data from the target dataset, for whole mammogram image classification. We compare the usage of semi-supervised learning on its own, and combined with transfer learning (from a source mammogram dataset) with data augmentation, as also against regular supervised learning with transfer learning and data augmentation from source datasets. It is shown that the use of a semi-supervised deep learning combined with transfer learning and data augmentation can provide a meaningful advantage when using scarce labelled observations. Also, we found a strong influence of the source dataset, which suggests a more data-centric approach needed to tackle the challenge of scarcely labelled data. We used several different metrics to assess the performance gain of using semi-supervised learning, when dealing with very imbalanced test datasets (such as the G-mean and the F2-score), as mammogram datasets are often very imbalanced