Dietary Phosphorus and Calcium Utilization in Growing Pigs: Requirements and Improvements

The sustainability of animal production relies on the judicious use of phosphorus (P). Phosphate, the mined source of agricultural phosphorus supplements, is a non-renewable resource, but phosphorus is essential for animal growth, health, and well-being. P must be provided by efficient and sustainable means that minimize the phosphorus footprint of livestock production by developing precise assessment of the bioavailability of dietary P using robust models. About 60% of the phosphorus in an animal's body occurs in bone at a fixed ratio with calcium (Ca) and the rest is found in muscle. The P and Ca requirements must be estimated together; they cannot be dissociated. While precise assessment of P and Ca requirements is important for animal well-being, it can also help to mitigate the environmental effects of pig farming. These strategies refer to multicriteria approaches of modeling, efficient use of the new generations of phytase, depletion and repletion strategies to prime the animal to be more efficient, and finally combining these strategies into a precision feeding model that provides daily tailored diets for individuals. The industry will need to use strategies such as these to ensure a sustainable plant–animal–soil system and an efficient P cycle.

The Gut Microbial Architecture of Efficiency Traits in the Domestic Poultry Model Species Japanese Quail (Coturnix japonica) Assessed by Mixed Linear Models

It is well known that mammals and avian gut microbiota compositions are shaped by the host genomes and affect quantitative traits. The microbial architecture describes the impact of the microbiota composition on quantitative trait variation and the number and effect distribution of microbiota features. In the present study the gut microbial architecture of feed-related traits phosphorus and calcium utilization, daily gain, feed intake and feed per gain ratio in the domestic poultry model species Japanese quail were assessed by mixed linear models. The ileum microbiota composition was characterized by 16S rRNA amplicon sequencing techniques of growing individuals. The microbiability of the traits was on a similar level as the narrow sense heritability and was highly significant except for calcium utilization. The animal microbial correlation of the traits was substantial. Microbiome-wide association analyses revealed several traits associated and highly significant microbiota features, both on the bacteria genera as well as on the operational taxonomic unit level. Most features were significant for more than one trait, which explained the high microbial correlations. It can be concluded that the traits are polymicrobial determined with some microbiota features with larger effects and many with small effects. The results are important for the development of hologenomic selection schemes for feed-related traits in avian breeding programs that are targeting the host genome and the metagenome simultaneously.

Efficacy of tertiary egg membranes as calcium zones for embryonic development in poultry breeds

Background Growth and production of any animal husbandry including poultry depends on early development, growth, feeding, environmental and other factors. Early and later embryonic development forms a significant parameter in poultry production, during which human or technological intervention is practically impossible. Results Embryonic development is governed by very many internal factors among which, egg calcium utilization is of prime importance. An experiment was set up to investigate the egg calcium utilization of different poultry breeds at its embryonic development. Four breeds of locally available chicken ( Gallus gallus domesticus ), Broiler, Common domestic variety ( Nadan ), Vanaraja and Gramapriya breeds were selected and embryonic egg utilization was assessed by comparing calcium content of egg shell before and after hatching and found out that Vanaraja breed utilizes maximum (0.20gm) and significantly (P < 0.01) higher quantity egg shell calcium for embryonic development followed by Local breed (0.16gm) and least used variety was Broiler breed (0.09gm). Conclusions The study highlighted the criticality of the composition of the specific mineral in the calcium zones for embryonic utilization underlining the importance of its only source through food.