Scheduling of a hydro producer considering head-dependency, price scenarios and risk-aversion

In this paper, a mixed-integer quadratic programming approach is proposed for the short-term hydro scheduling problem, considering head-dependency, discontinuous operating regions and discharge ramping constraints. As new contributions to earlier studies, market uncertainty is introduced in the model via price scenarios, and risk aversion is also incorporated by limiting the volatility of the expected profit through the conditional value-at-risk. Our approach has been applied successfully to solve a case Study based on one of the main Portuguese cascaded hydro systems, requiring a negligible computational time

Differences in Blood and Milk Fatty Acid Profile of Primiparous and Multiparous Mediterranean Buffaloes Cows During Transition Period and Early Lactation

The objective of this study was to determine the differences in blood and fatty acid (FA) profile between primiparous and multiparous Mediterranean buffaloes cows from 28 days of expected calving date until 56 days in milk. Nine multiparous (MUL) and 7 primiparous (PRI) cows were used in the present study, animals grazed in Brachiaria decumbens and supplemented with 2.0 kg of concentrate/day. Blood and milk samples were collected once a week and data were submitted to repeated measures analysis using PROC MIXED of SAS. Multiparous cows presented higher concentrations of glucose and non-esterified FA during pre- and post-partum period, higher cholesterol during post-partum when compared to PRI. Milk yield and fat content were higher for MUL (6.44 kg/d and 7.89%) when compared to PRI (5.66 kg/d and 6.75%). Palmitic and palmitoleic FA were lower and C18:0, C18:1 trans-11 and C18:1 cis-9 FAwere higher in MUL cows. Multiparous buffalo cows demonstrated higher milk yield and fat content than PRI, and milk FA profile of MUL had higher amounts of C18:0 FA. Multiparous buffalos presented higher non-esterified fatty acid, which altered milk fat content, and higher milk yield than primiparous cows. Furthermore, multiparous cows presented a higher content of FA from incomplete biohydrogenation process

Supplementation of diets for Santa Ines sheep with organic and inorganic zinc sources

This research was conducted with objective to evaluate the effect of different zinc (Zn) sources and doses in the diet for Santa Ines sheep. Forty lambs at weaning, with 18.4 kg of body weight were supplemented with three different sources of zinc (zinc oxide (ZnO), zinc amino acid and zinc proteinate) and three doses of zinc (200, 400 and 600 mg/kg DM) added to the basal diet. At every 28 days, animals were weighted and blood samples were collected for analyses of zinc (Zn), alkaline phosphatase and immunoglobulin G (IgG) and M (IgM). At the end of experiment, liver samples were collected for determination of the hepatic zinc levels. Zinc was analyzed with atomic absorption spectrophotometer, while phosphatase alkaline and immunoglobulins G and M were analyzed using Laborlab and Bioclin kits, respectively. There was no effect of diets on phosphatase alkaline levels and hepatic zinc, but there was difference in the plasmatic zinc levels and IgG and IgM levels. Based on the accumulation of hepatic zinc, the estimate of the zinc bioavailability, through the regression equation, showed that supplementation with organic and inorganic sources of zinc did not differ in the diet of Santa Ines sheep