State of the Art Pullet and Breeder Nutrition

During the last six to seven decades, broilers have been successfully selected for maximum growth and feed efficiency (Zuidhof et al., 2014). Modern fast-growing broilers reach a body weight of 2.0 to 2.5 kg in 35 to 45 days with an average daily growth of 55 or more gram a day (Augère-Granier, 2019). In a study with different broiler strains representative of broilers in 1957 or 1978 were compared with a broiler strain from 2005 (Zuidhof et al., 2014). The 2005 strain showed, over a 56-day growth period, a 4.6 times higher growth rate and a 50% lower feed conversion ratio. Besides the improvement in growth performance of broilers, body composition has changed as well during the last sixty to seventy years. The selection on increased feed efficiency and growth rate, and decreased body fat content has not only affected the offspring but also the parent stock (broiler breeders) (van Emous, 2015). Although the poultry breeding companies have worked to maintain or even increase the rates of egg production and hatchability (Laughlin, 2009), achieving these potentials at the broiler breeder farm level on a consistent level has proven to be more challenging (Renema et al., 2013). Therefore, optimization of the diet and feeding management is necessary to achieve maximal reproduction (van Emous, 2015). The main objective during the rearing phase is to produce pullets of ideal weight, uniformity, condition and stage of sexual maturity. The main objective during the laying phase is producing fertile, good quality and clean eggs (van Emous et al., 2020)

Maatregelen ter verminderding van fijnstofemissie uit de pluimveehouderij; factorenstudie stofemissie bij verschillende volièresystemen

Uit verschillende volièresystemen emitteren verschillende hoeveelheden fijnstof. Uit de factorenstudie blijkt dat dit niet veroorzaakt wordt door de verschillende lay-out van de systemen maar veel meer door de kwaliteit van het strooise

Maatregelen ter vermindering van fijnstofemissie uit de pluimveehouderij: gescheiden bedekte strooiselruimten bij legkippen = Measures to reduce fine dust emission from poultry houses: separated covered floor bedding for laying hens

In this study it was investigated whether covered bedding areas are able to reduce dust emissions from laying hens. The study shows that laying hens in an aviary system preferred dust bath behaviour under the tiers. Also in deep litter houses the number of hens that displays dust bath behaviour on the covered bedding area is probably not sufficient to give a relevant reduction of dust emissions. Further research on this principle is not recommended

Carbon Emissions Reduction and Corporate Financial Performance:The Influence of Country-Level Characteristics

Using a cross-country dataset covering 9265 observations on 1785 firms representing 53 countries over the period 2004–2019, this study investigates the relation between carbon emissions reduction and corporate financial performance (CFP). We perform OLS regressions with fixed effects. We found that carbon emissions reduction increases the return on assets, the return on equity, and the return on sales, whereas it has no effect on the Tobin’s Q and the current ratio. The positive relationship with the return on assets is stronger for firms with a higher responsibility score. We study country characteristics by modeling GDP growth, overall emissions within a country, and the presence of carbon emissions legislation. Our results indicate that the overall carbon emissions of a country and the presence of carbon emissions legislation are related to both corporate carbon emissions reduction and CFP. Moderating effects of the country’s overall emissions and the presence of carbon emissions legislation do not affect the relationship between carbon emissions reduction and CFP. Despite the further understanding gained, the issue of whether it “pays to be green” can still not be resolved well

Maatregelen ter vermindering van fijnstofemissie uit de pluimveehouderij : effecten van strooisellaagdikte

Emissions of fine dust from poultry houses with floor bedding are high. In layer houses, applying a thin layer of bedding will reduce fine dust emission. In broiler houses, a thick layer of bedding will affect production results and is therefore not a suitable measure to reduce fine dust emissions from broiler

Innovatie in huisvesting van vleeskuikenouderdieren: onderzoek en evaluatie = Innovation for broiler breeder housing: research and evaluation

In the future broiler breeder farmers have to meet legislation on the topics environment and animal welfare. The different housing systems who are ready for future are monitored on all factors. Systems near to the traditional system mostly score positiv

Verlichtings-, ammoniak-, stof- en arbeidsonderzoek bij twee volieresystemen

De belangrijkste resultaten van een ronde onderzoek naar twee voliOresystemen. Er zijn geen verschillen gevonden in technische resultaten, uitvalsoorzaken, percentage buitennesteieren en kwaliteit van het verenkleed. Dankzij terugdimmen van de verlichting kon het percentage bne's in de hand worden gehouden. Het onderzoek leverde een behoorlijk reductie op ten opzichte van de huidige norm van 90 gram per dierplaats per jaar. Uit het stofonderzoek is gebleken dat in de huidige voliOresystemen nog steeds veel stof wordt geproduceerd. Een ruimere opzet van de stellingen geeft een beter overzicht en bij sommige handelingen tijdsbesparing. Brede stellingen maken het rapen van buitennesteieren en verzamelen van dode dieren lastiger

Body composition and reproduction in broiler breeders: impact of feeding strategies

ABSTRACT Key words: broiler breeder, feeding strategies, body composition, reproduction, behavior Nowadays, welfare issues in broiler breeders associated with nutrition and reproductive characteristics, are becoming increasingly challenging. Due to genetic selection on broilers, body composition of breeders has changed dramatically during the last 50 years to less fat and more breast muscle. It is postulated that a certain amount of body fat in broiler breeders at the onset of lay is necessary for maximum performance and offspring quality. Body composition of breeders can be influenced by different feed allowances during rearing and lay, as well as by changes in nutrient composition of the diet. However, little is known about the effects of body composition on reproduction of broiler breeders. In this thesis, we investigated the effects of different feeding strategies during the rearing period on body composition at the end of rearing. Moreover, the effects of differences in body composition at the end of rearing, and feeding strategies during lay were evaluated on breeder performance, incubation traits, offspring performance, behavior and feather cover. From this study, it can be concluded that feeding a low protein diet during rearing decreased breast muscle and increased abdominal fat pad, whereas providing an increased feeding schedule, which resulted in a high growth pattern, only increased abdominal fat pad, at the end of rearing. The higher abdominal fat pad content resulted in an increased hatchability during the first phase of lay and a larger number of eggs during the second phase of lay. For maintaining growth pattern, broiler breeders had to provide a higher amount of feed with an increased energy to protein ratio compared to broiler breeders that were fed a diet with a standard energy to protein ratio. This resulted in an increased eating time and less stereotypic object pecking, which may indicate a reduced hunger and frustration. On the other hand, a low daily protein intake during the rearing and first phase of lay can lead to a poor feather cover. Feeding a high-energy diet during the second phase of lay resulted in increased hatchability, decreased embryonic mortality and more first grade chicks. </p

Verlichting bij leghennen in volieresystemen

In juni 2000 is een nieuw koppel leghennen geplaatst in stal P5 van het Praktijkcentrum 'Het Spelderholt'. Er wordt onder andere onderzoek gedaan met bruine leghennen in twee voliOresystemen met twee verschillende verlichtingssystemen. In dit artikel gaan we in op de tussentijdse resultaten van het verlichtingsonderzoek in de voliOresystemen

Systeem van de toekomst voor leghennen

Het Praktijkonderzoek Veehouderij wil samen met andere kennisinstellingen de huidige inzichten gebruiken om te komen tot een geheel nieuw houderijsysteem. Uitgangspunt bij dit systeem van de toekomst is dat het op zijn minst moet passen binnen de voorwaarden van duurzame huisvestingssystemen voor leghennen