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Raineri C.,University of Sao Paulo | Antonelli R.,University of Sao Paulo | Prosdocimi Nunes B.C.,University of Sao Paulo | de Barros C.S.,University of Sao Paulo | And 3 more authors.
Revista Colombiana de Ciencias Pecuarias | Year: 2012

The demand for "welfare friendly" products increases as public conscience and perception on livestock production systems grow. The public and policy-makers demand scientific information for education and to guide decision processes. This paper describes some of the last decade contributions made by scientists on the technical, economical and market areas of farm animal welfare. Articles on animal welfare were compiled on the following themes: 1) consumer behavior, 2) technical and economical viability, 3) public regulation, and 4) private certification policies. Most studies on the economic evaluation of systems that promote animal welfare involved species destined to produce export items, such as eggs, beef and pork. Few studies were found on broilers, dairy cows and fish, and data regarding other species, such as horses, sheep and goats were not found. Scientists understand that farm animal welfare is not only a matter of ethics, but also an essential tool to gain and maintain markets. However, it is unfortunate that little attention is paid to species that are not economically important for exports. Studies that emphasize on more humane ways to raise animals and that provide economic incentives to the producer are needed. An integrated multidisciplinary approach is necessary to highlight the benefits of introducing animal welfare techniques to existing production systems. Source

Molina I.C.,National University of Colombia | Angarita E.A.,National University of Colombia | Mayorga O.L.,Colombian Agricultural Research Corporation | Chara J.,Centro Para La Investigacion En Sistemas Sostenibles Of Produccion Agropecuaria | Barahona-Rosales R.,National University of Colombia
Livestock Science | Year: 2016

A rapid growth of the meat production industry is necessary to satisfy increased demand for this commodity, which might have negative impacts on the environment. The objective of this study was to assess enteric methane (CH4) emissions when a forage legume is introduced in the diet of animals consuming a tropical grass. Eight Lucerna heifers, 218±18 kg live weight with an average age of 19±3 months were used in two experiments following a changeover design. The diets evaluated were 100% star grass (Cynodon plectostachyus, S) or 76% star grass plus 24% leucaena (Leucaena leucocephala, S+L). Throughout the experiment, animals were housed in two chambers, in which the diet was offered four times daily. Each chamber had a small wind tunnel, which housed a fan set to a constant speed of extraction. Air samples were obtained every hour during 24 h both inside and outside (ambient) the tunnel. Methane concentration in these samples was determined by gas chromatography. Temperature and relative humidity both inside and outside the tunnel were recorded using a thermo-hygrometer. The S+L diet had greater protein content whereas the S diet had greater content of neutral detergent fiber. Average intake (kg/d) of fresh forage and dry matter (DM) was significantly greater (23.7 and 5.6) for the S+L than for the S diet (18.9 and 4.7), respectively (P<0.05). The maximum recorded temperature and humidity inside the chamber was 35.5 °C and 99%, respectively, but the minimum values were 19.1 °C and 38%, respectively. Methane production (L/kg DMI) was 37.7 for the S+L treatment and 43. 6 for the S treatment. The energy loss in the form of methane emitted was 8.0% for S+L and 9.4% for the star grass based diet (P=0.32). These results suggest that while increasing animal productivity by increasing dry matter intake, the inclusion of leucaena does not increase methane emission per animal, thus significantly decreasing methane emissions per kg of meat or milk produced. © 2016 Elsevier B.V. Source

Henao-Gallego N.,University of Valle | Escobar-Ramirez S.,University of Valle | Calle Z.,Centro Para La Investigacion En Sistemas Sostenibles Of Produccion Agropecuaria | Montoya-Lerma J.,University of Valle | Armbrecht I.,University of Valle
Restoration Ecology | Year: 2012

Ants are effective at moving seeds toward their nests, something that may benefit the seeds. We evaluated whether seed movements that may be useful for the rehabilitation of degraded pastures in Colombia can be enhanced by local ants. An artificial aril was prepared and then evaluated in six open cattle pasture farms. Twenty paper disks (each holding seeds with an artificial aril, honey, tuna oil, and control) were set up along linear transects at each farm, and monitored five times in 48 hours. A total of 340 out of 480 seeds were moved from the experimental units by ants. Seeds with tuna oil and an artificial aril were removed twice as frequently as the control and honey smeared seeds. Ectatomma ruidum, Solenopsis geminata, and Pheidole sp. removed the majority of seeds. Advantages of the artificial aril over tuna oil are discussed. This inexpensive technique can enhance seed movement by generalist ants in degraded pastures, likely contributing to regeneration and ecological rehabilitation. © 2011 Society for Ecological Restoration International. Source

Chara-Serna A.M.,Centro Para La Investigacion En Sistemas Sostenibles Of Produccion Agropecuaria | Chara J.D.,Centro Para La Investigacion En Sistemas Sostenibles Of Produccion Agropecuaria | Zuiga M.C.,Centro Para La Investigacion En Sistemas Sostenibles Of Produccion Agropecuaria | Zuiga M.C.,University of Valle | And 2 more authors.
Universitas Scientiarum | Year: 2010

Objective. To determine the trophic structure of the aquatic insect assembly associated to eight streams in the Colombian coffee-growing ecoregion. Materials and methods. Aquatic insects were collected in eight forested streams located in La Vieja river basin. The taxa collected were assigned to dietary groups according to a regional classification based on the gut content analysis of aquatic insects associated to forested streams of the Otún river basin. Results. 2019 individuals belonging to 73 taxa were collected and 60 were classified into dietary groups. The most abundant group was collectors (55%), followed by shredders (31%) and predators (10%). Scrapers represented only 0.05% of the sample and the remaining 3,95% could not be classified due to lack of information. Conclusions. The dominance of collectors and shredders reveals the importance of coarse particulate organic matter (leaf litter) as a food resource for the insect fauna. Similarities between the trophic structure of this community and other communities studied in similar streams, suggest the possibility of a common pattern for Andean streams. This study evidenced the lack of knowledge on trophic ecology of tropical aquatic insects; 50% of the taxa collected did not have this kind of information for the tropics and 20% had no information neither for the tropics nor temperate zones. Source

Boyero L.,CSIC - Donana Biological Station | Boyero L.,James Cook University | Pearson R.G.,James Cook University | Dudgeon D.,University of Hong Kong | And 32 more authors.
Ecology | Year: 2011

Most hypotheses explaining the general gradient of higher diversity toward the equator are implicit or explicit about greater species packing in the tropics. However, global patterns of diversity within guilds, including trophic guilds (i.e., groups of organisms that use similar food resources), are poorly known. We explored global diversity patterns of a key trophic guild in stream ecosystems, the detritivore shredders. This was motivated by the fundamental ecological role of shredders as decomposers of leaf litter and by some records pointing to low shredder diversity and abundance in the tropics, which contrasts with diversity patterns of most major taxa for which broad-scale latitudinal patterns haven been examined. Given this evidence, we hypothesized that shredders are more abundant and diverse in temperate than in tropical streams, and that this pattern is related to the higher temperatures and lower availability of high-quality leaf litter in the tropics. Our comprehensive global survey (129 stream sites from 14 regions on six continents) corroborated the expectedlatitudinal pattern and showed that shredder distribution (abundance, diversity and assemblage composition) was explained by a combination of factors, including water temperature (some taxa were restricted to cool waters) and biogeography (some taxa were more diverse in particular biogeographic realms). In contrast to our hypothesis, shredder diversity was unrelated to leaf toughness, but it was inversely related to litter diversity. Our findings markedly contrast with global trends of diversity for most taxa, and with the general rule of higher consumer diversity at higher levels of resource diversity. Moreover, they highlight the emerging role of temperature in understanding global patterns of diversity, which is of great relevance in the face of projected global warming. © 2011 by the Ecological Society of America. Source

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