High Dietary Calcium Causes Metabolic Alkalosis in Egg-Type Pullets

Abstract

One hundred sixty healthy egg-type pullets were randomly divided into 2 groups at 35 d of age. The groups were fed either with a normal-calcium (control, 8.5 g of Ca/kg) diet or with a high-calcium (HC, 36.3 g of Ca/kg) diet, respectively. The experiment lasted for 32 d. The healthy situations of the egg-type pullets were observed. Blood gas values and serum and urine electrolyte content were determined. The HC diet caused watery excreta in pullets. The pullets raised on the HC diet had significantly higher blood pH, bicarbonate, base excess, and significantly lower blood partial pressure of oxygen, partial pressure of carbon dioxide, and oxygen saturation than the pullets raised on the control diet. Phosphorus and potassium decreased; meanwhile, calcium increased in the HC group as compared with the control group. Sodium, magnesium, and chloride in serum had no significant difference between the HC group and the control. The pullets raised on the HC diet had significantly higher urine pH than the pullets raised on the control diet. For HC pullets, urinary concentration and 24-h urinary excretion of calcium and chloride was significantly higher, and magnesium, inorganic phosphorus, and sodium was significantly lower than that of the control pullets. It is concluded that some metabolic disorders associated with high dietary calcium in egg-type pullets may be related to a state of metabolic alkalosis.

Quantitative trait loci identified for blood chemistry components of an advanced intercross line of chickens under heat stress

“…Metabolic alkalosis occurs when there is a disturbance in the fixed acids and bases in the extracellular fluid [ 11 ]. Imbalance of dietary Na, K, or Ca can result in metabolic alkalosis [ 34 ], which is characterized by an increase in blood pH, HCO 3 , and base excess, and can be induced in growing layers by high levels of calcium in feed [ 35 ].…”

Association of partial pressure of carbon dioxide in expired gas and arterial blood at three different ventilation states in apneic chickens (Gallus domesticus) during air sac insufflation anesthesia

“…Although normal BE values for mature male white Leghorn chickens have not been reported, the BE value for a control group of 1 month old egg‐type pullets was 2.25 mmol L −1 with a pH of 7.42 (Guo et al. ). In this study, the median BE in all three ventilations states was >2.25 mmol L −1 which suggests that these chickens had an underlying metabolic alkalemia or that BE values can differ considerably between chickens of different age and sex.…”

Nutritional modulation of health, egg quality and environmental pollution of the layers

“…In the last 2 decades, requirements of minerals and vitamins for pullets and laying hens were seldom studied. Guo et al. (2008) reported the metabolic alkalosis caused by high dietary calcium content (3.63%) on 5-wk-old pullets.…”