search.noResults

search.searching

saml.title
dataCollection.invalidEmail
note.createNoteMessage

search.noResults

search.searching

orderForm.title

orderForm.productCode
orderForm.description
orderForm.quantity
orderForm.itemPrice
orderForm.price
orderForm.totalPrice
orderForm.deliveryDetails.billingAddress
orderForm.deliveryDetails.deliveryAddress
orderForm.noItems
HEALTH ▶▶▶


Above photos show a longitudinal section of the head of the tibia bone (tibia). The white border just above the arrows is the articular cartilage. The gray layer underneath is the growth plate (where bone formation takes place). If bone formation is disturbed, this layer will become thicker. Below this layer are the bone bars which mark the start of the actual bone. In the photo on the left the arrow points to a slightly widened growth plate, while the photo on the right shows a strongly widened growth plate which – according to the study – results from a lack of phosphate.


starter feed. All the data were then analysed using a statistical model.


Hens have better bone formation The results (see Table 1) showed that some parameters are strongly related to the quality of bone formation. One of these parameters is the sex of the chick. Hens have better bone formation than males (independent of body weight). It is striking that hens also have a higher phosphate level in the blood. A higher phosphate level (regardless of gender) ap- pears to be significantly (p <0.005) correlated with better bone formation and with higher body weight. Roosters gen- erally have a lower level of phosphate in the blood as well as poorer bone quality. However, a higher calcium level in the blood had less influence on better bone formation in both males and females. What was also striking in this study is that a higher pH in the stomach was associated with a higher


32 ▶ POULTRY WORLD | No. 3, 2021


calcium level in the blood, yet it was not associated with a higher phosphate level in the blood.


Phosphate ‘promotes’ bone formation The research led to a number of surprising insights. It was ex- pected that hens would have better bone quality. But the fact that this was related to higher blood phosphate levels and less to higher blood calcium levels was a surprise. Further- more, it appeared that a higher pH in the stomach was asso- ciated with higher calcium levels in the blood, but this had less effect on bone quality. Higher phosphate levels were positively correlated with body weight, although a causal re- lationship could not be established in this study. In conclu- sion, it appears that it is not the calcium, but the phosphate level which is a more important factor to take into account when optimising broiler feed, in particular, to ensure proper bone formation.


PHOTOS: GVP EMMEN


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44