A revised model for studying phosphorus and calcium kinetics in growing sheep.
نویسندگان
چکیده
The objective of the study was to revise a model of P kinetics proposed by Vitti et al. (2000) and extend its use to study Ca flows in growing sheep. Twelve Santa Ines male sheep, 8 mo of age, with average BW of 31.6 kg were injected with 32P and 45Ca to trace the movement of P and Ca in the body. The original model had 4 pools representing the gut, plasma, soft tissues, and bone. In the revised model, instantaneous values rather than averages for pool derivatives were incorporated, and the model was extended to represent absorption and excretion of phytate P explicitly. The amendments improved the model, resulting in higher flows between plasma and bone than between plasma and tissue and, therefore, a more accurate representation of P metabolism. Phosphorus and Ca metabolism were then assessed conjointly using the revised model. The results showed that P and Ca metabolism are closely related as evidenced by the ratio of these minerals in the bidirectional flows between plasma and bone and between plasma and tissue. Phytate P digestibility was 47%, and P retention was negative (-1.4 g/d), suggesting that a feed characteristic impaired P utilization and led to P deficiency. The revised model provides an improved prediction of P and Ca metabolism that can be used to assess mineral requirements and to estimate losses to the environment.
منابع مشابه
Calcium and Phosphorus Metabolism in Growing Pigs Studied by the Balance Technique and Simultaneous Radio-calcium and Radio-phosphorus Kinetics
متن کامل
A Model for the Stratification of Dairy and Mutton Sheep Breeds in Middle Eastern Deserts
than any of the other grass mixtures when collected in the cured stage. Since aphosphorosis did not occur during the winter blood sampling period, phosphorus accumulated during the growing period on winter and alpine ranges may influence blood phosphorus during the winter when forage phosphorus is in short supply. At this time it is not known to what degree a free-ranging animal can accumulate ...
متن کاملFailure of bone phosphorus levels to indicate dietary intake of phosphorus by sheep.
Fifteen actively growing lambs were divided into 3 groups and fed diets similar in all respects except for their calcium (Ca) and phosphorus (P) levels. The diets (Group 1; 1,47% Ca, 0,36% P: Group 2; 0,85% Ca, 0,47% P: Group 3; 0,37% Ca, 0,64% P) were fed to the animals for 98 days, when rib biopsy specimens were removed and analysed for Ca and P (Group 1; 21,20% Ca, 10,49% P: Group 2; 19,54% ...
متن کاملتأثیر مقادیر مختلف کلسیم و فسفر قابل دسترس جیره بر عملکرد مرغان مادر بومی اصفهان
In a 3×3 factorial experiment, 90 72-week-old native breeder hens of Isfahan were kept in cages (one bird/cage). The effect of three levels of dietary calcium (3.27, 2.62, and 1.96%) and three levels of dietary available phosphorus (0.25, 0.20, and 0.15%) on egg production and egg shell traits were investigated. Each treatment contained five replicates of two birds (10 birds per treatment). The...
متن کاملتأثیر مقادیر مختلف کلسیم و فسفر قابل دسترس جیره بر عملکرد مرغان مادر بومی اصفهان
In a 3×3 factorial experiment, 90 72-week-old native breeder hens of Isfahan were kept in cages (one bird/cage). The effect of three levels of dietary calcium (3.27, 2.62, and 1.96%) and three levels of dietary available phosphorus (0.25, 0.20, and 0.15%) on egg production and egg shell traits were investigated. Each treatment contained five replicates of two birds (10 birds per treatment). The...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Journal of animal science
دوره 84 10 شماره
صفحات -
تاریخ انتشار 2006