Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

Methiorep®, an herbal methionine premix, which is reported to contain herbal ingredients that mimic the activity of Methionine such as SAMe (S-Adenosyl Methionine) and phosphatidyl choline, have recently introduced to Nigeria animal feed industry. An experiment was conducted with 120, one-week-old broilers to evaluate the effect of herbal methionine (methiorep®) as substitute for synthetic methionine on growth performance of broiler chickens. Five isocaloric and isonitrogenous diets were formulated and Diet 1 (control), comprised of 0.25% methionine (NRC, 1994) while diet 2, 3, 4 and 5 comprised of 25%, 50%, 75% and 100% Methiorep® as substitute for methionine in the diets. The birds were randomly allocated to five experimental treatments, each treatment was replicated three times with eight birds per pen in a completely randomized design. The study lasted 49-days. The results of growth performance revealed that body weight gain, average feed intake and feed conversion ratio at both starter and finisher phases were not  influenced by dietary treatments (P>0.05). However cost per kg feed decreased as the level of Methiorep® increased in the diets (P<0.05). The results of blood profiles and carcass characteristics were not influenced (P>0.05) by the dietary treatments. It was concluded that Methiorep® can completely substitute for Methionine in the diets of broiler chickens without adverse effect on growth performance, blood profiles and carcass yield of birds.

Las ovejas domésticas (Ovis aries) descienden del muflón asiático y fueron domesticadas en el cercano oriente. Posteriormente, se diseminaron hasta el oeste de África, lugar de donde se cree, provienen los ancestros de la oveja Pelibuey. La oveja Pelibuey fue traída a América por los españoles para alimentar a la tripulación de las embarcaciones. No está claro si estos animales provenían del oeste africano o de las Islas Canarias. Se considera que la oveja Pelibuey ingresó a México entre 1930 y 1940, aunque algunos autores piensan que ya existía en el país desde finales del siglo XIX. A partir de 1963, la oveja Pelibuey ha sido la raza ovina más estudiada en México, debido a su capacidad para producir en zonas tropicales y a su alta adaptabilidad a otras zonas agroecológicas del país. Una breve revisión de las características productivas y reproductivas de algunos rebaños actuales, permite concluir que son muy parecidos a los de las primeras ovejas estudiadas hace casi 50 años. Actualmente, la raza ha sido objeto de cruzamientos indiscriminados para incrementar su productividad, lo que pone en riesgo este importante recurso genético. Por lo tanto, existe la necesidad de realizar la conservación de la raza.

Little research has been conducted in Kenya to ascertain and exploit the ability of pigeonpea  to improve soil fertility and increase cereal yields. An experiment was conducted at Katumani Research Centre between 2009 and 2013 to evaluate the effects of pigeonpea on soil fertility and productivity of maize cropping systems in semi-arid Kenya. The experiment was established as a split-split plot design with sole and intercrops of maize and pigeonpea varieties drawn from three maturity groups and three crop residue application rates as the treatments. Results showed that intercropping maize with pigeonpea reduced (p ≤ 0.05) soil organic carbon and total soil N from 1.4 and 0.2 % in 2009 to less than 1 and 0.1 %, respectively, in 2013. Intercropping maize with long duration pigeonpea and ploughing back 4 t ha-1 of crop residues had no significant effect on available P. However, it increased (p ≤ 0.05) available P from 26 ppm at the start of the study to 50 ppm and 47 ppm in eight seasons under maize-Mbaazi I and maize-Kat 60/8 intercrops, respectively. Exchangeable K, Mg and Ca also declined significantly (p ≤ 0.05). Intercropping maize with long duration pigeonpea and ploughing back 4 t ha-1 of crop residues offers the best option since it gave higher maize (1.9 t ha-1) and pigeonpea (1.4 t ha-1) grain yields per season and sufficient crop residues to feed the livestock and plough back to improve soil fertility.   

Anthracnose (Colletotrichum gloeosporioides Penz.) is one of the most important diseases of mango (Mangifera indica L.) due to its wide distribution in the world and to induce severe epidemics in the vegetative and reproductive stages, causing important production losses. The objective of this research was to evaluate the tolerance to C. gloeosporioides infection in the vegetative stage of eleven new mango cultivars in Mexico with potential in the export market. Leaves of 15 days old of development were inoculated with the Gro isolate highlighted in virulence. Based on the incubation, period, incidence and severity, "Alphonse", "Neelum", "Kesar and Ivory” cultivars were low susceptibility, “Nam Doc Mai”, “Rosygold”, “Cotaxtla” were highly susceptible, and "Fairchild", "Ataúlfo Diamante", "Ataúlfo Zafiro" and "Mallika" had medium susceptibility. The longer incubation periods determined the lowest severity (r2= -0.89 and -0.90) and incidence (r2= -0.77 and -0.85). The incidence correlated positively with severity (r2= 0.86 and 0.92), both inoculation techniques (DLT and ALT) were useful to induce typical symptoms of anthracnose and to estimate the expression of virulence (incubation period, incidence and severity) of the pathogen. La antracnosis (Colletotrichum gloeosporioides Penz.) es una de las enfermedades más importantes del mango (Mangifera indica L.) debido a su amplia distribución en el mundo y por inducir severas epidemias en etapas vegetativas y reproductiva que conllevan a importantes pérdidas de producción. El objetivo de esta investigación fue evaluar la tolerancia a la infección por C. gloeosporioides en etapa vegetativa de once nuevos cultivares de mango en México con potencial en el mercado de exportación. Se inocularon hojas de 15 días de desarrollo con el aislamiento virulento Gro. Basándose en los períodos de incubación, incidencia y severidad, los cultivares "Alphonse", "Neelum", "Kesar e “Ivory" presentaron baja susceptibilidad, "Nam Doc Mai", "Rosygold", y "Cotaxtla" fueron altamente susceptibles mientras que  “Fairchild”. “Ataúlfo Diamante”, “Ataúlfo Zafiro” y "Mallika" exhibieron susceptibilidad media. Los períodos de incubación más largos determinaron la menor severidad (r2 = -0.89 y -0.90) e incidencia (r2 = -0.77 y -0.85). La incidencia se correlacionó positivamente con la gravedad (r2 = 0,86 y 0,92), ambas técnicas (DLT y ALT) de inoculación fueron útiles para inducir síntomas típicos de antracnosis y para estimar la expresión de virulencia (período de incubación, incidencia y severidad) del patógeno.

African locust bean (Parkia biglobosa) seed is rich in protein and has recently found its way into the feed industry. This research was conducted to determine the growth performance, haematological profile and nutrient digestibility by broiler chickens fed diets containing soaked and fermented African locust bean (Parkia biglobosa) seed meal (SFALBSM). Five diets were formulated in which SFALSBM was included at graded levels of 0, 7.5, 15, 22.5 and 30% designated as T1, T2, T3, T4 and T5 respectively. Two hundred and twenty five (225) day old broiler chickens (Marshall Strain) were fed these diets in a completely randomized design and each treatment was replicated three times with 15 birds per replicate. The experiment lasted 8 weeks (4week starter phase and 4week finisher phase). The results of performance of broiler chicks at starter phase showed there were differences (P<0.05) in final body weight (734.25 - 937.81 g) and total weight gain of birds (679.13 -898.31 g). T3 had the highest body gain compared to other treatments. Similarly, final body weight of broilers at finisher revealed that birds fed T3 and T4 (2786.14 g and 2686.14 g) were higher (P<0.05) than those fed other diets. Birds fed T5 had the lowest value (2312.73g). There were differences (P<0.05) in the feed conversion ratio (3.26 - 4.55) and feed cost per kilogram gain (222.33 - 316.70 N/kg gain). The best feed conversion ratio was observed on birds fed T3 diet. The results of blood analysis showed that there were differences (P < 0.05) in the packed cell volume (23.33 - 27.67 %), total glucose (129.22 - 161.01 mmol/l), and red blood cell (3.30 - 4.29 X106/l).  There were no effect (P >0.05) on digestibility of dry matter, crude protein and ash. The crude fibre, ether extract and nitrogen free extract digestibility were affected by treatments (P<0.05). Birds fed T3 had highest crude fibre digestibility value (P<0.05). It was concluded that soaked and fermented African locust bean seed meal can be included in broiler chickens diets up to 15% dietary level at the starter phase and 22.5% at the finisher phase without any adverse effect on performance, haematological profile and nutrient digestibility.

Records of beef cows from a ranch in southern Mexico gave 1967 birth weights (BW), 1587 weaning weights adjusted to 210 days of age (AWW) and 2001 calving intervals (CI) for the comparison of the breed groups: Brahman (BR), Guzerat (GU), Nellore (NE) and crosses born to zebu dams by Brown Swiss sires. Animals were fed mainly pasture. Data were analysed using general linear procedures. The statistical model that described the data for BW and AWW included the fixed effects of breed group (BR, GU, NE, BS x BR, BS x GU and BS x NE); year of birth or calving (2005 to 2014), season of parity of the cow (dry, rainy, windy), sex of the calf (female or male), parity (1 to =>8) and the simple interaction of year x season of birth or calving. The model for CI was similar to the previous one, except that only the Zebu purebreds were included. The overall means and standard deviations for BW, AWW and CI were 33.5+0.75 kg, 178.9+19.7 kg and 456.4+79.2 days. All effects included in the model had significant effect on BW and AWW, but season and sex on CI. The smallest least squares means for BW corresponded to the cross of BR x NE and the largest to the cross of BS x BR (33.3 and 33.7 kg, respectively); whereas the lowest and largest least squares means for AWW corresponded to the NE (173.8 kg) and BS x BR (191.8 kg). NE cows had shorter CI than BR and GU cows (413.9, 446.2 and 481.3, respectively). Male calves weighed more at birth and weaning than females. Year x season interaction indicate that season effects on performance of calves or cows were not similar throughout the years studied. 

El ‘realismo mágico’: una categoría crítica necesitada de revisión

Juana Castro o la voluntad de una escritura femenina