This work presents a conceptual analysis of the main biotechnologies used in Chilean salmoniculture, which is based on the production of Atlantic salmon (Salmo salar, 356.407 t),silver salmon or coho (Oncorhynchus kisutch, 116.481 t), (O. tshawytscha, 2.062 t) and rainbow trout (O. mykiss, 189.178 t).These activities are focused on the photoperiod artificial manipulation to obtain out-of-season spawning, in the use of hormonal therapies which allow synchronizing the final oocyte maturation (FOM) and sexual maturity acceleration or the increase in milt […]

The objective in this trial was to estimate the energy requirements of supplemented Zebu bulls grazing Brachiaria decumbens paddocks. Twenty eight intact males, seven months old and initial body weight 180 kg were used. Eight animals were slaughtered as reference, in different weight ranges. The net energy requirements for weight gain were obtained by regressing the log of the retained energy (RE) on the log of empty body weight (EBW). The net energy requirements for maintenance (NEm) were obtained from […]

In the early 1970’s research was initiated by the cooperative USDA-ARS and University of Nebraska grass breeding program to develop perennial grasses adapted to the mid-continental USA with improved forage quality. The initial breeding and animal evaluation work focused on switchgrass (Panicum virgatum) but has since expanded to several other warm-and cool-season perennial grasses. The in vitro dry matter digestibility (IVDMD) test was selected as the measure of forage quality that was used in the breeding work because of its […]

The objective was to evaluate the results of supplementation in the dry season of the year and the possible interference of the forage availability and quality and level of supplementation on performance. The total DM and green dry matter pasture availability deferred for use in the dry season has an average of all experiments of 6,431 kg ha-1 and 2,173 kg ha-1. The Brachiaria under grazing in the dry season have high levels of NDF, with an average of 74.50%, […]

This manuscript reports on the main problems decreasing productivity of dairy cows (e.g. fatty liver syndrome and poor fertility) and how antioxidants could enhance it. High producing dairy cows are prone to oxidative stress, and the situation can be exacerbated under certain environmental, physiological, and dietary conditions. Antioxidants have important effects on the expression of genes involved in the antioxidant status, which may enhance animal health and reproduction. Moreover, antioxidants may contribute to decrease the incidence of spontaneous oxidized flavour […]

One third to one half of each animal produced for meat, milk, eggs, and fiber is not consumed by humans. These raw materials are subjected to rendering processes resulting in many useful products. Meat and bone meal, meat meal, poultry meal, hydrolyzed feather meal, blood meal, fish meal, and animal fats are the primary products resulting from the rendering process. The most important and valuable use for these animal by-products is as feed ingredients for livestock, poultry, aquaculture, and companion […]

Two levels of concentrate (20 and 40% dry matter) and presence or absence of propolis ethanolic extract (PEE) in the diet at 30% w/v were evaluated in this study. The intake and apparent digestibility of nutrients, milk production and composition, live weight, feed efficiency and concentrate use for milk production were evaluated. Eight Holstein cows were distributed in two 4 × 4 Latin squares. The experiment was carried out in four 21-day periods, the first fourteen days were for the […]

From the origins the man has looked and selected vegetables with nutritive value for larger productivity. The knowledge of DNA structure allowed genetic engineering to develop and supplying tools for the accomplishment of specific alterations in the genome considerably. The products of these alterations are denominated transgenic or organisms genetically modified (OGM) and they present high application potential in several areas of the human activity as: agriculture, medicine, health, production and processing of foods, biochemical production and control of diseases. […]

The confinement reactivity (CR) has been used as a measure of temperament in Brazil and it is defined as the animal reaction when contained in the scale. It is quantified through the animal reactivity test – REATEST®. This test consists of an electronic device coupled to the scale and of specific software. The device captures the movement that the animal provokes in the scale, during 20 seconds and sends it for the software that processes this movement and determines the […]

This paper aims at exploring what is covered by « adapting to last » with a farming systems approach. Long term dynamics can be analysed as adaptive cycles, the system being permanently exposed to disturbances and shocks. Mobilizing the concept of resilience, we analyse the factors that differentiate the principles for long term action the livestock farmers have, principles which give consistency to the family – farms trajectories. With the concept of operational flexibilty, we qualify the sources of flexibility […]