Prediction of soil nutrient content via pXRF spectrometry and its spatial variation in a highly variable tropical area

Precision Agriculture - Precision agriculture provides detailed information on the spatial variability of soil properties, including nutrient content, allowing for local-specific decision making....     

Microclimate and development of black pepper intercropped with rubber tree

Agroforestry Systems - Pepper producers are searching for more sustainable production systems. Shaded cultivation is presented as a management option to attenuate black pepper environmental...     

Effects of feeding yeast (Saccharomyces cerevisiae), organic selenium and chromium mixed on growth performance and carcass traits of hair lambs

Yeasts and organic minerals are used in diets to improve health, productive performance and some carcass characteristics of ruminants and non-ruminants. Thirty-two lambs(Pelibuey×Katahdin; BW=(30.55±1.67) kg; n=8) were used in a 56-d feeding experiment to study the effects of different levels of live yeast(Saccharomyces cerevisiae; yeast), selenium(Se) and chromium(Cr) mixed(Se-Cr), and a mixture of yeast-Se-Cr on growth performance and carcass traits. Animals were stratified by body weight(BW) and randomly assigned to one of four treatments: 1) control group(0.0 g kg–1 yeast); 2) yeast(1.50 g kg–1 dry matter intake(DMI) d–1); 3) Se-Cr premix(1.5 mg kg–1 DMI d–1 for each mineral); and 4) yeast-Se-Cr mixture. There were no treatment effects on final BW; whereas lambs fed Se-Cr or yeast-Se-Cr had higher(P<0.05) DMI than animals supplemented with only yeast. Average daily gain(ADG), gain:feed ratio, chop area, dorsal fat and carcass yield were similar(P>0.05) among treatment groups. In conclusion, supplementation with yeast, Se-Cr mixed or yeast-Se-Cr did not improve ADG, final BW, back fat content and carcass yield of growing of Pelibuey×Katahdin lambs. Supplementation with Se-Cr and yeast-Se-Cr increased DMI, and approximately 250 g ADG animal–1 d–1 was produced with no negative effects on growth and health of the animals.     

Effect of processing on some chemical and nutritional characteristics of pre-cooked and dehydrated legumes

The effect of processing on chemical composition and protein quality of three legumes was studied. The species analyzed were beans (Phaseolus vulgaris), Tórtola and Coscorrón varieties; lentils (Lens esculenta), Laird variety; and chick peas (Cicer arietinum), California-INIA variety. The legumes were soaked in a solution of Na₂ EDTA at 0.03% for 16 h and cooked for a predetermined period for each species. They were dried in a tray drier with cross currents of air flowing at a speed of 10 m/min until the residual mositure content was 8%. The water activity in the resulting products ranged from 0.574 to 0.587, thus completely assurring no microbial activity. No important changes were observed in the legumes protein, fat, or fibre contents after processing. The soaking solution was effective in reducing the phytic acid content from 2.99 to 1.64 mg/100 g in the Tórtola beans, which had the highest acid value prior processing. In all the species the heat treatment reduced the activity of the trypsin inhibitors by at least 50%. Cooking and drying significantly increased protein digestibility in all the legumes studied, with chick peas showing the most dramatic increase: from 54.7% pre-processing to 94.9% post-processing. With regard to Net Protein Ratio (NPR), chick peas had a value of 4.03, followed by Tórtola beans (3.29), Coscorrón (3.09) and lentils (2.61). The NPR value for the casein diet was 4.20.     

Influence of Fruit Ripening Stage and Harvest Period on the Antioxidant Content of Sweet Pepper Cultivars

Pepper (Capsicum annuum L.) fruits are highly appreciated by producers and consumers for their economical and nutritional value. Four different cultivars of coloured peppers in immature and mature stages were harvested throughout the spring and examined for their content of phenolic compounds, ascorbic acid and total antioxidant capacity (TAA) as well as for lipid peroxidation and carbonyl proteins as index of oxidative stress. Ripening and harvest period influenced the antioxidants and the development of oxidative processes in the cultivars differently: lipid peroxidation increased in mature peppers except in one cultivar (Y1075), while no changes in protein oxidation or in TAA were produced, except in Y1075 in which both parameters increased. Each cultivar presented differences in antioxidant compounds depending on the harvest period, but we could recommend May as the optimal if all cultivars have to be harvested at the same time, when levels of ascorbate, phenols and TAA were not decreased, fresh weight and proteins were elevated, and levels of oxidation were not as high as in June (except for Y1075). A previous study of the response of each cultivar to different environmental conditions results essential to establish a good program of selection of cultivars with high quality and productivity.     

Biochemical Composition and Indigestible Oligosaccharides in Phaseolus vulgaris L. Seeds

Common beans have a high nutritional value, but contain galactooligosaccharides (GO), which cause flatulence and intestinal discomfort in humans. The biochemical composition of ten bean cultivars was determined to select those of high protein and low GO contents. The cultivars varied in carbohydrate (47.02–60.17%), GO (3.12 – 5.71%), protein (22.17–33.50%), lipid (1.13–1.81%), moisture (11.42–12.93%) and ash contents (4.08–5.61%). ‘Mexico 222’ presented the highest α-galactosidase activity. Protein and GO contents were positively correlated. ‘Perry Marrow’ combined high protein and low GO concentrations, indicating it can be used in improvement programs aiming at high-quality cultivars for human consumption.     

Anthelmintic resistance impact on tropical beef cattle productivity: effect on weight gain of weaned calves

The performance of grazing cattle in tropical areas is deeply influenced by parasitism, and the increasing reports of resistance are a threat to effective nematode control. The present study aimed to evaluate the effect of avermectins on the performance of weaned calves naturally infected by ivermectin-resistant gastrointestinal nematodes. The effect of four commercial endectocides (ivermectin 2.25 % + abamectin 1.25 %, ivermectin 3.15 %, doramectin 3.15 %, and doramectin 1 %) on parasitism and performance of a hundred weaned Nellore calves were evaluated during 112 days. The most effective anthelmintic showed efficacy of 84 % and resulted in an increase (P?<?0.05) of live weight gain of 11.85 kg, compared to untreated group, 9.05 and 9.41 kg compared to those treated with more ineffective avermectins which showed efficacy of 0 and 48.2 %, respectively. A significant (P?<?0.05) and weak negative correlation (r?=??0.22) between the eggs per gram (EPG) and body weight was observed, indicating that even the low mean EPG (175?±?150) observed at day 0 in the control group, with predominance of Haemonchus sp., was responsible for production losses. These results indicate that control of nematode parasites in beef cattle in the weaning phase may not result in increased productivity when carried out without technical criteria.     

Performance and characteristics of carcass and non-carcass components of lambs fed peach-palm by-product

The objective of this study was to evaluate the effects of supplying the by-product of peach-palm (Bactris gasipaes) on performance and characteristics of carcass and non-carcass components of feedlot lambs. Twenty Santa Ines lambs of 150 days average age and 22.4?±?3.4 kg body weight were confined in individual pens. A completely randomized design was utilized with four experimental diets composed of: fresh peach-palm by-product enriched with urea, fresh peach-palm by-product + concentrate, silage of peach-palm by-product + concentrate, and silage of peach-palm by-product enriched with 15 % corn meal + concentrate. Intake was evaluated daily, and at the end of 42 days of experiments, lambs were slaughtered and the characteristics of carcass and non-carcass parts were evaluated. Performance and carcass characteristics showed differences between the animals’ intake of total mixed rations (TMR) and only the diet with roughage. For the lambs that intaked TMR, the form of utilization of roughage (fresh or as silage) affected animal performance but did not change the carcass characteristics. Dry matter intake and feed conversion were influenced by the form of utilization of the silage (with and without additive). Providing fresh by-product plus concentrate improves lamb performance but does not interfere in the carcass characteristics, compared with the use of by-product in the form of silage.