Nutritional properties of potato protein concentrate compared with soybean meal as the main protein source in feed for the double-muscled Belgian Blue bull.

The objective of this experiment was to compare the nutritional properties of potato protein concentrate, a by-product of the starch industry produced entirely in Europe, with that of soybean meal (SBM), for growing cattle. The experiment was conducted on double-muscled Belgian Blue bulls, fitted with rumen, duodenal and ileal cannulas, according to a 4 × 4 Latin square design. They were fed three different iso-N and iso-net energy diets formulated according to the Dutch feed evaluation system, differing in the nature of the main protein source, which was either SBM ('SBM' treatment), potato protein concentrate (PPC, 'PPC' treatment) or an iso-N mixture of these two protein sources ('mixed' treatment). A fourth treatment consisted of 'PPC' supplemented by 9.5% digestible proteins supplied by duodenal perfusion of sodium caseinate (CAS, 'PPC + CAS' treatment). No significant difference was observed in the ruminal fluid pH, whereas both 'PPC' and 'PPC + CAS' had the effect of reducing the ruminal ammonia nitrogen (N-NH3) concentration. No significant difference was observed in the apparent intestinal digestibility of the dry matter (DM), organic matter (OM) or N. Outflows of non-NH3-N, microbial proteins and dietary proteins from the rumen were similar for 'PPC', 'SBM' and 'mixed', and increased with CAS infusion by 20%, 17% and 27%, respectively. On the basis of in vivo observations, the degradability of SBM and PPC proteins was estimated at 0.60 and 0.43, respectively, corresponding to the values quoted in the literature. The supply of digestible essential amino acids (EAA) was significantly greater with 'PPC + CAS' and did not differ among 'SBM', 'mixed' and 'PPC'. This illustrates the difficulty of altering the amino acid (AA) pattern of digestible protein by the nature of the protein of dietary origin when an animal is fed a high nutritional value diet. N retention was not affected by replacing SBM with PPC, but increased by 10% with CAS infusion. On the basis of the plasma AA pattern, the supply of digestible Met was probably limiting with 'SBM', 'mixed' and 'PPC'. The CAS perfusion supplemented all AA, including Met, leading to increased N retention. This improvement was limited, however, and N utilisation remained unchanged between treatments. In conclusion, despite a more favourable EAA pattern, PPC offered no advantage compared with SBM for growing bulls when diets were formulated according to the Dutch feed evaluation system.

A new versatile database created for geneticists and breeders to link molecular and phenotypic data in perennial crops: the AppleBreed DataBase.

OBJECTIVE: AppleBreed DataBase (DB) aims to store genotypic and phenotypic data from multiple pedigree verified plant populations (crosses, breeding selections and commercial cultivars) so that they are easily accessible for geneticists and breeders. It will help in elucidating the genetics of economically important traits, in identifying molecular markers associated with agronomic traits, in allele mining and in choosing the best parental cultivars for breeding. It also provides high traceability of data over generations, years and localities. AppleBreed DB could serve as a generic database design for other perennial crops with long economic lifespans, long juvenile periods and clonal propagation. RESULTS: AppleBreed DB is organized as a relational database. The core element is the GENOTYPE entity, which has two sub-classes at the physical level: TREE and DNA-SAMPLE. This approach facilitates all links between plant material, phenotypic and molecular data. The entities TREE, DNA-SAMPLE, PHENOTYPE and MOLECULAR DATA allow multi-annual observations to be stored as individual samples of individual trees, even if the nature of these observations differs greatly (e.g. molecular data on parts of the apple genome, physico-chemical measurements of fruit quality traits, and evaluation of disease resistance). AppleBreed DB also includes synonyms for cultivars and pedigrees. Finally, it can be loaded and explored through the web, and comes with tools to present basic statistical overviews and with validation procedures for phenotypic and marker data to certify data quality. AppleBreed DB was developed initially as a tool for scientists involved in apple genetics within the framework of the European project, 'High-quality Disease Resistance in Apples for Sustainable Agriculture' (HiDRAS), but it is also applicable to many other perennial crops.

Culture medium and protein supplementation in the generation and maturation of dendritic cells.

Dendritic cells (DC) are powerful antigen-presenting cells that have drawn many attentions due to the recent development of anti-cancer vaccines. Clinical grade production of monocyte-derived DC (Mo-DC) is extensively studied, and many efforts are made to develop and improve clinical standard operating procedures. Most of the parameters involved, such as the cytokines and maturation agents, have been widely assessed. However, very few are investigated about how culture medium and additional protein components affect DC yield, viability and maturation. Thus, our study aimed to compare the impact of standard culture medium on Mo-DC differentiation and maturation. Commercially available media for hematopoietic cell culture as well as different protein supplementations, that is foetal calf serum (FCS), autologous plasma (AP), human serum (HS) and human serum albumin (HSA) were tested. Culture yields, cell viability and DC maturation were investigated. Differentiation yields were similar between the conditions used. However, we evidenced significant differences in terms of cytotoxicity and DC maturation (phenotypic and functional). This underscores the importance of defining culture medium composition in clinical standard operating procedures to insure quality control, and also when preparing DC for experimental uses.

Comparative study of anti-drift nozzles' wear.

When spraying, the drift is a restricting factor which reduces the efficiency of pesticides treatments and increases their impact on the environment. The use of anti-drift nozzles is the most common technique to reduce the drift effect. The basic principle of all anti-drift nozzles is to produce bigger droplets (Imag DLO, 1999) being less sensitive to the wind. The increase of the droplets' size is possible whether by reducing the spraying pressure (anti-drift fan nozzle) or by injecting air in the nozzle (air injection nozzles). This study aims at comparing the performances of the main anti-drift nozzles available on the Belgian market (Teejet DG and AI, Albuz ADI and AVI, Hardi ISO LD et AI). The study made it possible to compare thirteen different nozzles' sets according to their trademark, type and material. The study is based on the analysis of macroscopic parameters (flowrate, transversal distribution and individual distribution) as well as on the analysis of microscopic parameters (spraying deposit on artificial target). The evolution of these parameters is analysed according to the nozzle's wear. The wear is carried out artificially according to the "ISO 5682-1" standard (ISO 5682-1, 1996). The results confirmed the major influence of the manufacturing material on the nozzles' wear, ceramic being the most resistant material. Macroscopic as well as microscopic parameters variated according to the utilization time without any direct correlation. Indeed, most parameters variate in an uncertain way. It was however possible to establish a correlation between the wear time and the recovering rate and flowrate parameters. The utilization length is different depending on the type of nozzle, air injection nozzles being more resistant. At last, the analysis of microscopic parameters (spraying deposit) (Degré A., 1999), shows that the number of impacts is stable depending on the wear, while the size of impacts and the recovering rate increase.

Rinsing and management of pesticides' containers.

In order to reduce the effects on the environment, it is necessary to improve the management of pesticides' containers. Usually, users burn or bury empty containers. These methods, even though decreasing must be avoided or even forbidden. Since 1996, empty containers are systematically collected in Belgium and are specifically removed by the firm Phytofar Recover created by the Belgian Federation of pesticides' manufacturers. Since the beginning, the recovery rate (percentage of containers recovered compared with the containers sold) goes on increasing to exceed 85% in 2001. These action and results are a world first (more than 500 tons of empty containers are collected yearly). Once collected, empty containers are subjected to the European Policy about toxic wastes since they contained dangerous products. Their removal must follow a specific removal process by incineration at very high temperature (> 1200 degrees C) with a specific filtration of the smoke. The treatment cost is high and reaches 2 Euros per kg of container. If the container is rinsed and the residue does not exceed 1000, 10,000 or 30,000 mg per kg of container (depending on the dangerousness of product: very toxic, corrosive or toxic), it will be considered as domestic waste and will therefore follow a much more economical energy production process. The study aims at determining the quantities of residue contained in empty containers and the parameters reducing the rinsing efficiency: the formulation (EC, WP, WG), the container's size, packaging's type (plastic container or paper bag), the rinsing technique. Almost 150 tests and analyses of residue have been carried out. A manual rinsing procedure has been set up in order to meet the standards about residue. Rinsing three times with an average volume of water (20 to 30%) allows to reach the lowest residue level. As bags containing powder (WG or WP) container not be rinsed, it is necessary to empty them completely. It is however difficult to reach the 1000 ppm residue limit.

[Seasonal variation in the nyctohemeral rhythm of prolactin in cows]. / Variation saisonniére du rythme nycthéméral de la prolactine chez les bovins femelles.

Seasonal variation of prolactin nyctohemeral rhythm has been studied by radioimmunoassay on female cattle of the white blue belgian breed. Animals are divided into three groups as age is concerned : 6 calves, 6 heifers and 5 lactating cows. In december all groups of animals show a significant increase of plasma prolactin concentration between 5 a.m. and 7 a.m. Calves and heifers have a second secretion period either at the end of the afternoon between 17 and 19 p.m. or during the evening between 20 and 23 p.m. The circadian rhythm observed in may with heifers is similar to that in december with two waves whose relative importance is different at the two seasons considered. Nyctohemeral rhythm of prolactin in cattle is age and season dependent.