Las relaciones entre ciencia y sociedad: hacia una sociología histórica del conocimiento científico

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Helping HELP with limited resources: The Luquillo experience

By definition the HELP approach involves the active participation of individuals from a wide range of disciplines and backgrounds, including representatives of industry, academics, natural resource managers, and local officials and community leaders. While there is considerable enthusiasm and support for the integrated HELP approach, a central problem for all HELP basins is how to effectively engage individuals and groups with few, if any financial resources. In the Luquillo HELP project we have managed this issue by focusing our efforts on holding small, public meetings and workshops with technocrats and managers who are engaged in local water resource management. To date several forums have been organised, including: technical meetings with the directors of natural resource agencies; presentations and panel discussions at the meetings of local professional societies, including the societies of Civil Engineers and Architects, the Commonwealth Association of Tourism, the Association of Builders and Developers, and the Puerto Rican Association of Lawyers. During these forums HELP specialists gave presentations and led discussions on how integrated watershed management can help resolve local problems. Because the audience are directly involved with these issues, they are quite responsive to these discussions and have often provided unique solutions to common problems. Technical workshops are co-sponsored by local municipalities – these day-long workshops are hosted by a municipality and include managers from other municipalities, the local water authority, and local community leaders. Additional activities include: technical advice on water infrastructure projects is given; there are educational exchanges between local and international students, scientists, natural resource managers, and community leaders; and synthesis publications relevant to integrated water resource management are produced. Other activities have included compiling oral environmental histories and organising watershed restoration activities. This paper describes these activities and discusses the benefits and costs of each approach.Keywords: integrated water resource management, tropical mountains, Puerto Ric

Methane Production of Fresh Sainfoin, with or without PEG, and Fresh Alfalfa at Different Stages of Maturity is Similar, but the Fermentation End Products Vary (vol 9, 197, 2019)

The authors wish to make the following correction to their paper [1]. In Table 2, the production of methane in alfalfa at the start-flowering should be 38 mL/g dOM and not 3 mL/g dOM. Table 2. Effect of the substrate (S) and the stage of maturity 1 (SM) on gas and methane production (CH4), potential gas production (A), rate of gas production (c), in vitro organic matter degradability (IVOMD), ammonia (NH3-N), and volatile fatty acids (VFAs). Table The authors would like to apologize for any inconvenience caused

Effect of the method of preservation on the chemical composition and in vitro fermentation characteristics in two legumes rich in condensed tannins

The objective of the present study was to evaluate the effects of preservation (hay and silage) on the chemical composition and the in vitro fermentation characteristics in comparison with fresh forage in two legumes rich in condensed tannins (CT). Sainfoin (Onobrychis viciifolia) was collected at the late bloom stage and sulla (Hedysarum coronarium) at the early bloom stage. In each forage, a part was immediately freeze-dried, a part was dried at ambient temperature to obtain hay, and another part was ensiled in vacuum-packages for 82 days. An in vitro assay to study the fermentation was carried out with an Ankom system during 72 h. In both forages, the silages had different contents of polyphenols and condensed tannins fractions than fresh forage and hay (P<0.05). Sainfoin hay only had greater content of fibre-bound CT fraction (FBCT) than fresh sainfoin, whereas sulla hay had greater protein-bound CT and FBCT contents than fresh sulla (P<0.05). Sainfoin silage had lower gas and methane production than hay and fresh forage (P < 0.001), whereas fresh sulla had greater gas and methane production, followed by hay and silage, which produced the least (P<0.05). In both legumes, hay had lower in vitro organic matter digestibility (IVOMD) than silage and fresh forage (P<0.001). The method of preservation affected the total production of volatile fatty acids (VFA) only in sulla (P<0.05). Most of the proportions of individual VFA were affected by the method of preservation in both legumes (P<0.001). In conclusion, polyphenols content, total content and fractions of CT were more affected in the silages than in the hays when compared to fresh forages. However, according to gas and methane production and IVOMD, silage may have greater feed nutritive value than hay although further studies on animal performance are warranted before recommendation

Milk fatty acid profiles of beef cows in response to a short feed restriction during lactation.

Abstract M75 The relationship between energy balance and the milk fatty acid (FA) profile is well established in dairy cows but has received little attention in beef cattle. We analyzed the milk fatty acid profile of 16 Parda de Montaña beef cows 2 mo post-calving in response to a 4-d (d) dietary restriction (55% of energy requirements, 6.2 kg dry matter (DM) hay/d), as compared with a previous basal and an 8-d refeeding period (100% of requirements; 7.0 kg DM/d hay + 2.7 kg DM/d concentrate). With d0 as the start of restriction, milk was sampled on days d-2 (basal), d1, d3 (restriction) and d5, d6, d8 (refeeding). Individual FA were identified by gas chromatography, and sums of FA were calculated (saturated (SFA), monounsaturated (MUFA), polyunsaturated (PUFA), cis-MUFA, trans-MUFA, C4-C15 de novo synthesis FA and C16-C24 mobilization FA). These sums and the 4 major FA (C16:0, C18:1–9c, C18:0, C14:0) were analyzed using mixed models, with day as fixed and cow as random effects. All the results presented here were significant at P < 0.001. The milk FA profile responded immediately to changes in the energy balance and/or the diet. On d1 of restriction, the concentrations of SFA decreased, mainly due to a reduction in the de novo synthesis FA and C16. A concomitant increase in MUFA (associated with that of C18:1–9c, predominant in body fat) was observed. These changes, along with the increments in C16-C24 FA, indicate an enhanced fat mobilization from the adipose tissue. During the restriction, C18:0 and trans-MUFA decreased while cis-MUFA and PUFA increased, as a result of both the mobilization and the change in diet composition..

Milk fatty acid profiles of beef cows in response to a short feed restriction during lactation.

Abstract M75 The relationship between energy balance and the milk fatty acid (FA) profile is well established in dairy cows but has received little attention in beef cattle. We analyzed the milk fatty acid profile of 16 Parda de Montaña beef cows 2 mo post-calving in response to a 4-d (d) dietary restriction (55% of energy requirements, 6.2 kg dry matter (DM) hay/d), as compared with a previous basal and an 8-d refeeding period (100% of requirements; 7.0 kg DM/d hay + 2.7 kg DM/d concentrate). With d0 as the start of restriction, milk was sampled on days d-2 (basal), d1, d3 (restriction) and d5, d6, d8 (refeeding). Individual FA were identified by gas chromatography, and sums of FA were calculated (saturated (SFA), monounsaturated (MUFA), polyunsaturated (PUFA), cis-MUFA, trans-MUFA, C4-C15 de novo synthesis FA and C16-C24 mobilization FA). These sums and the 4 major FA (C16:0, C18:1–9c, C18:0, C14:0) were analyzed using mixed models, with day as fixed and cow as random effects. All the results presented here were significant at P < 0.001. The milk FA profile responded immediately to changes in the energy balance and/or the diet. On d1 of restriction, the concentrations of SFA decreased, mainly due to a reduction in the de novo synthesis FA and C16. A concomitant increase in MUFA (associated with that of C18:1–9c, predominant in body fat) was observed. These changes, along with the increments in C16-C24 FA, indicate an enhanced fat mobilization from the adipose tissue. During the restriction, C18:0 and trans-MUFA decreased while cis-MUFA and PUFA increased, as a result of both the mobilization and the change in diet composition..

Carotenoids and liposoluble vitamins in the plasma and tissues of light lambs given different maternal feedings and fattening concentrates

The carotenoids and liposoluble vitamins in the plasma and tissues of the lambs under different maternal feedings and fattening concentrates was studied. During lactation, 21 lambs were housed with their dams, that received a total mixed ration (intensive); 21 ewe–lamb pairs grazed on alfalfa; and 21 pairs grazed on sainfoin. After weaning, half of the lambs in each maternal feeding group received a commercial concentrate (control) and the other half a concentrate with quebracho (Schinopsis balansae), as a source of condensed tannins, until they were slaughtered (23 kg). The analyte concentrations in the plasma of lambs at weaning reflected the content in the feedstuffs. Grazing during suckling more than doubled the contents of lutein in the liver and retinol in the tissues compared to the intensive feeding. The content of a-tocopherol in the tissues was greatest in sainfoin lambs, intermediate in alfalfa lambs, and lowest in the intensive lambs. The quebracho concentrate decreased a-tocopherol (by 41–81%) and ¿-tocopherol (by 65–89%) contents in the lamb tissues. The use of the analytes in the plasma at weaning correctly classified 100% of the lambs into the maternal feeding (intensive vs. grazing (alfalfa + sainfoin)) but has to be improved in the carcass and tissues separately

Meat quality of light lambs is more affected by the dam’s feeding system during lactation than by the inclusion of quebracho in the fattening concentrate

The inclusion of natural antioxidants in the diet, through fresh forages or condensed tannins, might prolong meat shelf life and modify the meat quality. The aim of this study was to evaluate the effect of the dam’s feeding system during lactation and the inclusion of quebracho in the fattening concentrate of male lambs on meat color, chemical composition, and lipid oxidation. Dams and their suckling lambs were fed indoors or allowed to graze on alfalfa or sainfoin until lambs reached 42 d old. Thereafter, the weaned lambs were fed concentrates with 5% quebracho or without quebracho until reaching 22 to 24 kg BW. Meat of suckling lambs from dam’s fed indoors (Indoor lambs) presented greater intramuscular fat content and lower a-tocopherol content than meat of suckling lambs from dam’s fed Alfalfa (Alfalfa lambs) and Sainfoin (Sainfoin lambs; P < 0.01), independent of the fattening diet. Regarding meat color of longissimus thoracis et lumborum muscle, on average, Indoor lambs’ meat presented greater lightness, yellowness, and hue angle values than Alfalfa and Sainfoin lambs’ meat (P < 0.05). The redness was affected by the interaction between the feeding system during lactation and the time of storage, but, on average, Alfalfa and Sainfoin lambs had greater redness than Indoor lambs (P < 0.05). The lipid oxidation from 5 to 14 d of meat display time observed for Sainfoin lambs was lower than that for Indoor lambs (P < 0.05). The intramuscular fatty acid profile of meat from the Sainfoin and Alfalfa lambs met particularly well the Food and Agriculture Organization of the United Nations recommendation for human health, compared that of meat from the Indoor lambs. The dietary inclusion of quebracho during fattening modified meat a-tocopherol content, oxymyoglobin levels after 8 d of storage, and fatty acid profiles. In conclusion, the results indicate higher importance of the diet during suckling than during the subsequent fattening period on meat quality parameters such as color, lipid oxidation, and fatty acid profile. Dams grazing Sainfoin provide a more stable lamb meat, and it would be cheaper to feed the dams with fresh forages with a high a-tocopherol content than supplementing the concentrate of the lambs with synthetic a-tocopherol

The Inclusion of Concentrate with Quebracho Is Advisable in Two Forage-Based Diets of Ewes According to the In Vitro Fermentation Parameters

Simple Summary In dry, mountainous areas, ewes are fed low-quality forages (hay or straw) indoors, although they also graze in high-quality pastures when available. Concentrate supplementation is recommended to cover high nutritional requirements during lactation. Condensed tannins (CT) of quebracho (Schinopsis balansae) can be included in the concentrate to reduce methane (CH4) emissions and ruminal degradation of protein, improving the fermentation’s efficiency. Furthermore, low levels of quebracho can improve some meat and milk quality traits. The effects of the inclusion of concentrate and CT in diets depend on the level of inclusion and the quality of forage. The aim of this study was to evaluate the in vitro fermentation characteristics of diets in order to identify the most suitable one to be fed to ewes under farming conditions. The diets examined differed in quality of the forage available, comparing hay versus fresh forage diets and forage alone versus 70:30 forage:concentrate with (quebracho) or without CT (control) in each type of forage. The fresh-forage-based diets had lower gas and CH4 production and greater in vitro organic matter degradability (IVOMD) than the hay-based diets. The inclusion of quebracho concentrate increased the IVOMD in hay-based diets and reduced ammonia content in fresh-forage-based diets. Abstract Ewes receive hay or graze on fresh pastures supplemented with concentrates to fulfil their lactation requirements. Quebracho (Schinopsis balansae) can be added to change the ruminal fermentation. Fermentation parameters of forages alone and 70:30 forage:concentrate diets with control and quebracho concentrate were compared after 24 h of in vitro incubation. Fresh forage diets produced less gas (p < 0.05) and had greater IVOMD (p < 0.001), ammonia (NH3-N) content, valeric acid, branched-chain volatile fatty acid proportions, and lower propionic acid proportion than the hay diets (p < 0.01). In the hay diets, methane production increased with control concentrate (p < 0.01) and tended to decrease with quebacho concentrate (p < 0.10). The inclusion of both concentrates increased the acetic:propionic ratio (p < 0.01), and only the inclusion of quebracho concentrate increased the IVOMD (p < 0.01). In the fresh forage diets, gas and methane production increased with the inclusion of the control concentrate (p < 0.05), but methane production decreased with quebracho concentrate (p < 0.01). The inclusion of quebracho concentrate reduced the NH3-N content and valeric acid proportion (p < 0.05). In conclusion, the inclusion of quebracho concentrate would be advisable to reduce the CH4 production and NH3-N content in fresh forage diets and to increase the IVOMD in hay diets in comparison with the forages alone