Excretie van biologisch gehouden leghennen, zeugen en vleesvarkens onder praktijkomstandigheden : Bouwstenen voor berekening van de stalbalans

Impact of calcium content and calcium to phosphorus ratio in diets for weaned pigs

“…The CVB recommendations are based on Ca and P retention in the body, including bone mineralisation. Requirements for maximum growth performance may be lower than for bone retention, as demonstrated for growing-finishing pigs by Bikker et al (2013). The Ca recommendations for weaned pigs are considered relatively high for practical diets.…”

“…The recommendations for Ca and P based on their use for bone mineralisation and retention in the body may exceed the requirements for maximum growth performance. This was illustrated in a dose response study in growing-finishing pigs in which maximum gain was realised at a P inclusion close to CVB recommendations, whereas Ca and P retention in the body continued to increase until the highest dietary P content of 130% of CVB recommendations (Bikker et al, 2013).…”

Stikstof-en fosfaatexcretie van gangbaar en biologisch gehouden landbouwhuisdieren : Herziening excretieforfaits Meststoffenwet 2019

“…This approach was used to make annual estimates of the mean gross nitrogen and phosphate excretion per animal category using data on the number of livestock, feed intake, diet composition, and retention in animal products. The gross nitrogen and phosphate excretion by animals in organic farming systems were based on those of conventional farming systems, which were adjusted using animal-specific correction factors derived by Bikker et al (2013Bikker et al ( , 2017. The gross nitrogen excretion was subsequently corrected for gaseous nitrogen losses based on the results of a new method described by Van Bruggen & Geertjes (2019).…”

“…stikstofexcretie is berekend als 120% van de excretie van reguliere gehouden leghennen (categorie 301), 125% van regulier gehouden opfokhennen (categorie 300) en 162% van regulier gehouden vleeskuikens in 2015-2017 op basis van de verhouding in excretie van biologisch en gangbaar gehouden dieren zoals beschreven doorBikker et al (2013Bikker et al ( , 2017). b) De fosfaatexcretie is berekend als 117% van de excretie van reguliere gehouden leghennen (categorie 301), 125% van regulier gehouden opfokhennen (categorie 300) en 205% van regulier gehouden vleeskuikens in 2015-2017 op basis van de verhouding in excretie van biologisch en gangbaar gehouden dieren zoals beschreven doorBikker et al (2013Bikker et al ( , 2017.…”