Nutrition: The integrative science

Whitehead, C. C.

doi:10.1080/00071660086330

Cited by 10 publications

(5 citation statements)

References 29 publications

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“…In the present study, it was observed that the inclusion of phytase in AACM diets resulted in a reduction of pancreas weight, which may be attributed to the interaction between phytic acid and digestive enzymes. Phytate was found to bind to endogenous proteases such as trypsin and chymotrypsin, as well as their precursors, during their passage through the digestive tract [50]. At certain concentrations of phytate, a ternary protein-metal-phytate complex can be formed, as both enzymes and their precursors have an affinity for Ca, further reducing the bioavailability of proteins and minerals [51].…”

Section: Discussionmentioning

confidence: 99%

The Impact of Phytase and Different Levels of Supplemental Amino Acid Complexed Minerals in Diets of Older Laying Hens

Medeiros-Ventura,

Rabello,

Santos

et al. 2023

Animals

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A study was conducted to evaluate the effects of different sources and levels of supplemental amino acid-complexed minerals (AACM), with and without enzyme phytase (EZ). A total of 512 Dekalb White laying hens at 67 weeks of age were used in a 2 × 3 + 2 factorial arrangement of 8 treatments and 8 replications each. The main effects included EZ supplementation (10,000 FTU kg−1) and AACM inclusion level (100, 70, and 40% of inorganic mineral recommendations), plus 2 control treatments. The group of hens fed AACM-100 showed lower feed intake than the inorganic mineral (IM) group. The diet containing AACM-EZ-70 provided a higher (p < 0.05) laying percentage and a lower (p < 0.05) feed conversion ratio than both the IM and IM-EZ diets. The groups fed AACM-EZ-40, AACM-EZ-100, and AACM-70 produced heavier yolks (p < 0.05). Hens fed IM laid eggs with the lowest yolk and albumen weights (p < 0.05). Layers fed with AACM-100 and AACM-70 produced the most resistant eggshells to breakage (p < 0.05). In diets containing phytase, the optimal AACM recommendations for better performance and egg quality in older laying hens are: 42, 49, 5.6, 28, 0.175, and 0.70 mg kg−1 for Zn, Mn, Cu, Fe, Se, and I, respectively.

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Section: Discussionmentioning

confidence: 99%

The Impact of Phytase and Different Levels of Supplemental Amino Acid Complexed Minerals in Diets of Older Laying Hens

Medeiros-Ventura,

Rabello,

Santos

et al. 2023

Animals

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“…History of poultry nutrition: K. Elwinger et al established the full aetiology of the disorder (Whitehead, 2000). The subsequent use of biotin as a routine feed supplement for broilers led to larger-scale industrial synthesis and marked reduction in cost.…”

Section: Disease Syndromes Related To Vitaminsmentioning

confidence: 99%

“…FURTHER FUNCTIONS RELATED TO VITAMINS Initially vitamin supply was mainly aimed at safeguarding optimal performance including lowest morbidity and mortality. Further criteria, where dosages above the normal nutritive requirements were used, for example for an improvement in immunological status (Leeson and Summers, 2001;Whitehead, 2000;Butcher and Miles, 2011). Investigations on these subjects started decades ago and are still ongoing at present.…”

Section: Disease Syndromes Related To Vitaminsmentioning

confidence: 99%

A brief history of poultry nutrition over the last hundred years

Elwinger

Fisher

Jeroch

et al. 2016

World's Poultry Science Journal

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“…Robinson et al (1991) observed 700 g difference in BW between ad libitum and the feed restricted groups at sexual maturity, out of which 62% was fat. Feed restricted birds are not free from hunger, but they have the welfare benefit of reduced metabolic disorders and mortality (Whitehead, 2000). However, feed restriction-induced stress in birds, particularly during early phase of growth, when metabolic requirements are high (Mench, 2002).…”

Section: Introductionmentioning

confidence: 99%

Effect of Measured Energy Restriction and Age Intervals on Growth, Nutrient Digestibility, Carcass Parameters, Bone Characteristics and Stress in Broiler Breeders during the Rearing Period

Sunder¹,

Kumar²,

Panda³

et al. 2008

Asian Australas. J. Anim. Sci

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This study aimed at targeting fixed increases in body weight (100 g/wk) by quantitatively regulating energy allowances (ME) in broiler breeders from 5 to 20 wks of age. Four energy regimes were tested: 1. The energy required for maintenance, activity and growth was calculated for 100 g increases in body weight/wk and a measured quantity of grower diet (160 g protein and 2,600 kcal ME/kg) was offered to the control group (ME-100) to achieve the anticipated weight gain. The energy allowances increased with age from 132 to 294 kcal/d. 2. Additionally, three energy regimes were considered, quantitatively reducing ME by 10% (ME-90) or 20% (ME-80) and increasing by10% (ME-110) over the control group. Each test group had 23 replicates×5 female chicks housed in cages. The influence of energy regimes and age on growth, nutrient digestibility, carcass attributes, bone parameters and stress was evaluated at 4 wk intervals. Quantitative ME restriction by 10% (119-265 kcal/d) produced an average weight gain of 98.1 g/wk, which was closer to the targeted increase of 100 g/wk, whereas the control group attained it nine days earlier. Restriction of energy by 10 or 20% produced better conversion efficiency of feed, energy and protein and apparent digestibility of protein, Ca and P than 10% excess ME. Energy regimes did not influence eviscerated meat yield, but higher energy allowances (ME-110) significantly increased abdominal fat pad and liver weights and decreased giblet weight, percent muscle protein and tibia ash. Relatively higher stress was recorded in ME-restricted groups, as reflected by wider heterophil and lymphocyte ratios and increased bursa weight. Early age (5-12 wk) significantly influenced bone mineralization, conversion efficiency of feed, energy and protein and apparent digestibility of protein, Ca and P, while later ages (13-20 wk) increased eviscerated meat yield, abdominal fat, tibia weight and muscle protein and reduced stress. Energy regime x age interactions were significant and are discussed. In conclusion, the synthetic broiler line used in our study responded positively to controlled energy feeding during the rearing period. Breeders offered 119-265 kcal/d, a reduction of 10% energy over the control group, were more effective in regulating grower performance than the latter. In addition to energy regimes, age intervals also exhibited significant influence on specific parameters during the grower phase.

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Nutrition: The integrative science

Cited by 10 publications

References 29 publications

The Impact of Phytase and Different Levels of Supplemental Amino Acid Complexed Minerals in Diets of Older Laying Hens

The Impact of Phytase and Different Levels of Supplemental Amino Acid Complexed Minerals in Diets of Older Laying Hens

A brief history of poultry nutrition over the last hundred years

Effect of Measured Energy Restriction and Age Intervals on Growth, Nutrient Digestibility, Carcass Parameters, Bone Characteristics and Stress in Broiler Breeders during the Rearing Period

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