scholarly journals The effect of dietary protein on reproduction in the mare. VI. Serum progestagen concentrations during pregnancy

Author(s):  
F.E. Van Niekerk ◽  
C.H. Van Niekerk

Sixty-four Thoroughbred and Anglo-Arab mares aged 6-12 years were used, of which 40 were non-lactating and 24 lactating. Foals from these 24 mares were weaned at the age of 6 months. Non-lactating and lactating mares were divided into 4 dietary groups each. The total daily protein intake and the protein quality (essential amino-acid content) differed in the 4 groups of non-lactating and 4 groups of lactating mares. The mares were covered and the effect of the quantity and quality of dietary protein on serum progestagen concentrations during pregnancy was studied. A sharp decline in serum progestagen concentrations was recorded in all dietary groups from Days 18 to 40 of pregnancy, with some individual mares reaching values of less than 4 ng/mℓ. Serum progestagen concentrations recorded in some of the non-lactating mares on the low-quality protein diet increased to higher values (p<0.05) than those of mares in the other 3 dietary groups at 35-140 days of pregnancy. A similar trend was observed for the lactating mares on a low-quality protein diet at 30-84 days of pregnancy. No such trends were observed in any of the other dietary groups. High-quality protein supplementation increased serum progestagen concentrations during the 1st 30 days of pregnancy. Lactation depressed serum progestagen concentrations until after the foals were weaned.

Author(s):  
F.E. Van Niekerk ◽  
C.H. Van Niekerk

The effect of total protein intake and protein quality on the serum concentrations of certain reproductive hormones during the anovulatory, transitional and ovulatory periods were studied in 36 Anglo-Arab mares. High-quality protein stimulated FSH and LH production during the late transitional period. Serum progestagen and melatonin concentrations were unaffected by the quality of protein nutrition during the anovulatory period. Mares receiving high-quality protein exhibited a 10-14-day cyclical pattern of FSH release approximately 4-6 weeks earlier than the mares fed the lower-quality protein diet, and also ovulated 3-4 weeks earlier than the mares on the lower-quality protein diet. Progesterone concentrations during the 1st oestrous cycle after the anovulatory period were unaffected by protein quality in the diet.


Author(s):  
Samy Fangus Sharobeem ◽  
Radomir Lásztity ◽  
Máté Hidvégi ◽  
András Salgó ◽  
Livia Simon-Sarkadi

1981 ◽  
Vol 8 (1) ◽  
pp. 61-65
Author(s):  
Josephine Miller ◽  
Timothy H. Sanders

Abstract Four cultivars of peanuts (Florigiant, Florunner, Starr and Tamnut) grown at two locations (Lewiston, North Carolina (NC) and Stephenville, Texas (TX)) in the National Regional Variety Trials were evaluated for protein nutritional quality. Peanuts, blanched with a minimum of heat treatment and partially defatted on a Carver press, were extracted with hexane at room temperature. Rats were fed these peanut meals to provide 10% of dietary protein (N × 6.25). PER was calculated as the ratio of weight gained to protein consumed for the 28-day feeding period. Adjusted PER values of the 8 peanut meals ranged from 1.3 to 1.7 compared to a value of 2.5 for the casein control diet. No statistically significant differences existed in PER among the 4 cultivars grown in NC. Florunner and Tamnut produced in TX had lower PER values than Florigiant and Starr grown at the same location. Florigiant, Florunner, and Tamnut grown in NC had lower PER values than the same varieties from TX. Rats were fed diets with Florunner peanut meal supplemented with methionine, lysine, and threonine, singly and in all combinations, for 7-day periods. Differences in protein quality between NC and TX-produced peanuts were overcome by addition of methionine to the diets. When all three amino acids were added, peanut meal from both locations supported growth of young rats equal to that of casein.


Aquaculture ◽  
1983 ◽  
Vol 34 (3-4) ◽  
pp. 213-238 ◽  
Author(s):  
David A. Higgs ◽  
Ulf H.M. Fagerlund ◽  
Jack R. McBride ◽  
M.Dianne Plotnikoff ◽  
Bakhshish S. Dosanjh ◽  
...  

1961 ◽  
Vol 18 (1) ◽  
pp. 85-91
Author(s):  
B. A. Larsen ◽  
W. W. Hawkins

Rats were used to test the digestibility and protein quality of dried preparations of muscle and viscera from cod and haddock, and of liver from cod.The digestibility of the preparations from muscle and viscera was good, and better than that of the preparation from liver.The metabolic utilization of nitrogen and the support of growth were good in the case of the muscle preparation, and poor in the case of the visceral and liver preparations.


2016 ◽  
Vol 9 ◽  
pp. 55-65 ◽  
Author(s):  
Kalep Bulus Filli

Extrusion cooking has beenused as an important technique for the manufacture and modification of widevariety of food products such as expanded snack foods, ready-to-eat cerealswhich are made from foods with high starch and protein. Although starchy foodsare the predominant structure forming agents, their utilization as food hasbeen limited by their poor protein quality and quantity. The supplementationwith legumes improves the essential amino acid content of the food. Bambaragroundnut has balanced amino acid content and can supplement the quality ofamino acids in sorghum. Starch from sorghum flour has been found to beresistant to extrusion. This makes the modification of functional propertiesvery difficult. Malting of the sorghum has been adopted for the modification ofthe starch quality. The nutrient and functional properties of food play majorrole in their application and use as food. This work has studied the effect offeed moisture (20%, 25%, and 30%) and barrel temperature (100o C,110OC and 130o C) on the chemical composition andfunctional properties of sorghum malt and Bambara groundnut blends. From theresults of the analyses, protein content varied from 11.07% to 11.75%. Increasein barrel temperature decreased the protein content while feed moistureincrease favoured the retention of proteins. The expansion index (EI), waterabsorption index (WAI) and effect of quantity of water on swell volume (EQWSV)varied from 1.88 to 3.88, 570% to 660% and 13.7 seconds to 33.4 secondsrespectively. These properties are negatively affected by increase in feedmoisture but they improve with increases in barrel temperature. The values forwater solubility index (WSI), bulk density and Wettability ranged from 2.2% to8.4%, 0.2g/cm3 to o.7g/cm3 and 14.3 seconds to 37.3seconds respectively. The increase in feed moisture has positive influence onthese parameters while temperature increased affected them negatively. 


1970 ◽  
Vol 48 (3) ◽  
pp. 188-192 ◽  
Author(s):  
E. Yanez ◽  
J. M. McLaughlan

Nitrogen intakes and weight changes of male weanling Wistar rats fed two or more levels of test proteins or a non-protein diet for 2 weeks were determined. The slope-ratio plot for multiple-dose assays showed clearly that proteins markedly deficient in lysine yielded invalid assays. NPR values for lysine-deficient protein were markedly higher when determined at the 5% than at the 10% level of protein but foods limiting in methionine, threonine, or lysine and threonine yielded similar values at the two levels of dietary protein. It was concluded that protein quality per se is not a fixed value and depends on the level of protein fed even at low and moderate concentrations. When PER, NPR, and slope-ratio values for several samples were expressed as a percentage of the values for casein, NPR and slope-ratio methods gave almost identical results but PER yielded low values for poor quality proteins. However, the three methods rated the eight test proteins in the same relative order.


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