Effect of Amino Acid Imbalance in Rats Fed Ad Libitum, Interval-fed, or Force-fed

In recent decades, recommendations on dietary protein content have been considerably reduced, while fibre content has been increased. Under these conditions, an adequate dietary amino acid balance could be crucial to optimise feed efficiency. Plasma urea nitrogen (PUN) level could be a good indicator of an amino acid imbalance and its potential has already been studied in other species, but not yet in rabbits. The main objective of the present work was to detect the possible interest of PUN in pinpointing amino acid deficiencies in rabbits. Two experimental diets were formulated from the same basal mixture, following all the recommendations for growing rabbits, except lysine, whose content was variable, following current guidelines in diet P8.1 or lower from those in P4.4 (with 8.1 and 4.4 g/kg dry matter of lysine and with 757 and 411 mg of lysine per MJ of digestible energy). Three different trials were designed: one where the animals were fed ad libitum (AL) and two others in which fasting periods of 10 h were included; one where feeding was restored at 08:00 h (Fast8h) and the other at 18:00 h (Fast18h). A total of 72 three-way crossbred growing rabbits (24 animals for each trial in a split-plot trial) up to a total of 12 recordings were used. Blood samples were taken every 4 h in AL trial and every hour after refeeding up to a total of six controls, in trials Fast8h and Fast18h. The differences between balanced and unbalanced diets in lysine were highest (P<0.001) between 04:00 h and 12:00 h in animals fed ad libitum, and at 3 h after refeeding (21:00 h) in Fast18h. These results suggest that PUN could be an adequate indicator to detect deficiencies in amino acids in growing rabbit diets.

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EVALUATION OF BLOOD-RUMEN CONTENT MIXTURE IN THE DIETS OF STARTER CHICKS

Nigerian Journal of Animal Production ◽

10.51791/njap.v28i2.1868 ◽

2021 ◽

Vol 28 (2) ◽

pp. 153-157

Author(s):

A. A. ADENIJI ◽

O. O. BALOGUN

Keyword(s):

Body Weight ◽

Amino Acid ◽

Control Diet ◽

Progressive Increase ◽

Soya Bean ◽

Rumen Content ◽

Optimum Level ◽

Crude Fiber Content ◽

Amino Acid Imbalance ◽

Ad Libitum

A trial with 234 day-old Olympian Black pullet chicks was conducted for a duration of eight weeks to determine the optimum level of inclusion of Blood-Rumen content Mixture (BRC) in the diet of starter chicks. Chicks were fed ad-libitum starter diets containing 0, 5, 10, 15, 20% BRC and another 20% BRC diet containing no soya bean cake. Birds on all BRC-based diets had higher body weight gains and higher feed intakes than birds on the control diet. A progressive increase in feed: gain ratio was observed from 10%BRC to 20% BRC in the diets. The decline in the performance of chicks fed higher levels of BRC in the diet is suggested to be due to the high crude fiber content and possible amino acid imbalance of such diets. The results of this trial shows that starter pullets should not be fed more than 10% BRC.

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Effect of amino acid imbalance on food intake and preference

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1962.202.1.165 ◽

1962 ◽

Vol 202 (1) ◽

pp. 165-170 ◽

Cited By ~ 39

Author(s):

Juan C. Sanahuja ◽

Alfred E. Harper

Keyword(s):

Amino Acid ◽

Food Intake ◽

Food Preference ◽

Food Selection ◽

Amino Acid Mixture ◽

Acid Mixture ◽

Balanced Diet ◽

Amino Acid Imbalance ◽

Ad Libitum ◽

Protein Free Diet

Effects of an amino acid imbalance, caused by adding 3.8% of an amino acid mixture lacking histidine to a diet containing 6% of beef fibrin, on the food intake and food preference of protein-depleted rats are described. After being depleted, animals fed the balanced or imbalanced diets ate equal amounts for 3 days, then both growth rate and food intake of those fed the imbalanced diet dropped. When protein-depleted rats were fed the balanced or imbalanced diet together with a protein-free diet, neither group ate the protein-free diet during the first 3 days. Thereafter, animals fed the imbalanced diet began to eat the protein-free diet in preference to the imbalanced diet, even though the latter would support growth and the former would not. Animals fed ad libitum the balanced diet or the imbalanced diet plus histidine did not eat the protein-free diet at all. These observations indicate that both food intake and food selection are influenced by the amino acid pattern of the diet.

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