Yield Components in Annual Ryegrass and Oats Grown in Association and Monoculture

Earliness of oats and higher growth rate of annual ryegrass later in the season explain the higher forage yield of annual ryegrass+oats association over monocultures (Améndola & Morales, 1997). However, changes in yield components of the species grown in association compared to monoculture have not been explored. This study aimed to determine leaf, stem and dead matter yield in annual ryegrass and oats when grown in association and monoculture at different nitrogen (N) levels

Juan Manuel Cuca García (1932 – 2021). In memoriam

Profile of Dr. Juan Manuel Cuca García (1932 – 2021)Semblanza Dr. Juan Manuel Cuca García (1932 – 2021)Perfil do Dr. Juan Manuel Cuca García (1932 – 2021

Plant Biomass and Bovine Live Weight Changes in Mono-Specific and Mixed Pastures during the Rainy Season in Dry Tropical Mexico

Dry tropics suffer long drought periods each year, negatively affecting the amount and digestibility of forage for cattle production. The aim of this study was evaluate different pasture types, grazed by cattle during the rainy season. Three hectares were prepared to compare: grass monoculture, Andropogon gayanus (G); a grass-legume mixture of A. gayanus and Clitoria ternatea (GL), and a grass-legume-tree mixture of A. gayanus, C. ternatea and Morus alba (GLT). Two grazing cycles (4 d grazing followed by 32 d resting; 72 d total) were completed. Three heifers (average initial weight 192 kg) grazed each experimental unit. The amounts of forage offered, remaining after grazing, and removed by animals differed significantly among the pasture treatments. Total forage offered by period was 2007, 4089, and 4192 DM kg/ha for G, GL, and GLT, respectively. Total residual forage was 1074, 1878 and 2613 DM kg/ha respectively, while total forage removed was 934, 2209, and 1579 DM kg/ha, respectively. Differences for offered forage were detected only for residual and consumed forage for GL prairies. Differences in available forage were mainly due to differences in the amount of stem and live material. Daily weight gain was 0.138, 0.504 and 0.501 kg per animal for G, GL, and GLT, respectively. Mixed pasture treatments yielded better live weight gain due to the better quality of available forage

Residual Forage and Animal Performance from a Kikuyo Pasture under Mixed Grazing and Supplementation

Five grazing strategies were compared: grazing by ewes only and mixed grazing (ewes + heifers), in mixed grazing heifers received no supplement or one of three supplements. Ruminal undegradable protein (RUP) varied among supplement: 4.25, 9.11 and 9.13%, the supplement with the highest RUP included protected methionine. All supplements were 21% crude protein and 3.0 Mcal/kg of metabolizable energy. Grazing was on kikuyu, ratio was 30 kg of ewe per 100 kg of heifer in the mixed grazing treatments. Experimental grazing lasted 84 days. Variables measured were residual forage, proline content in residual forage and liveweight gains per animal and per hectare. Experimental design was a completely random with two replicates. Residual forage was the highest (P\u3c 0.05) in mixed grazing and RUP in supplement was above 4.25%. The highest (P\u3c 0.05) proline content was found in grazing by ewes only, 52% above the proline content found in mixed grazing without supplement, when heifers received supplement proline content decreased (P\u3c 0.05) further. Grazing by ewes only and mixed grazing with heifersreceiving the highest RUP in supplement showed the highest (P\u3c 0.05) daily liveweight gain per ewe of 134 g. Mixed grazing in which heifers received no supplement gave a 100% increase (P\u3c 0.05) in liveweight gain per hectare compared to grazing by ewes only. In mixed grazing offering a supplement with 9.13% RUP and protected methionine gave both the highest liveweight gains per animal and per hectare. It was concluded that mixed grazing allowed a lower stress level on kikuyu due to defoliation and a higher liveweight gain per hectare than grazing by ewes only

Uses of Native Plant Species of a Communal Rangeland within ‘Sierra de Huautla’ Protected Area, México

Sustainability of communal rangelands has become a major concern at national and international levels because land use conflicts and associated social conflicts allows for over-utilization of selected species making a high pressure on them and given away their places to species with no use at all becoming lands degraded and unproductive. The objective of the study was to determine floristic composition and native plant uses by local peasants. The range surface is of 4262 ha, belongs to the communal land ‘El Limon’, in Tepalcingo, Morelos, Mexico, and it is within the Natural Reserve Area “Sierra de Huautla”. Native vegetation is mainly of deciduous shrubs, high temperatures year round and a rainy season of 4 months. Local peasants were surveyed on uses of the collected and previously identified plants. Number of species was 456, distributed in 266 and 76 botanical genders and families, respectively. Of the species identified 66, 22 and 12% had one, two or more than two uses according to local peasants. Among uses: 59% of the species were used as forage, 8% eatable, 7% firewood or ornamental, 6% medical herb, lumber or other use 4 %, construction material 3 % and for resin or handcraft 1%. The range showed a very high plant biodiversity, this feature allows for a high resiliency toward human activities