Effect Of Protein Nutrition Research Articles

The effect of protein nutrition on production, metabolic transformation of nitrogen and ecological load in dairy farming

The aim of the study is to evaluate the relation of protein nutrition to transformation of nitrogen (N) from feed to milk and its urinary excretion in dairy cows under the farm conditions. In breeding conditions of dairy farms in the groups of dairy cows in the 1st phase of lactation, with low content of CP (139±11.8 g/kg), optimum (161.8±6.3 g/kg) and high content of CP (179.7±8.5 g/kg) in dry matter of total mix ration (TMR), was confirmed the effect of increased the level of ammonia (NH3) in the rumen (17.4±1.7; 19.6±2.3; 22.8±3.4 mg/100 ml). The same tendency with higher statistical significance (P<0.001) was confirmed to the increased concentration of urea in the blood (22.8±3.7; 27.8±4.8; 35.1±6.6 mg/dl) and to the concentration of urea in the milk (18.2±2.6; 24.8±3.9; 33.3±6.7mg/dl). In the groups with increasing content of CP in the TMR, the ecological load of the environment increases, that was confirmed by a significant increase (P<0.001) of excreted N in the urine (139.4±19.8; 189.5±30.4; 254.7± 51.3 g N/day) and an increase (P<0.001) in the emission of ammonia into the environment (68.1 ± 6.1; 83.7 ± 9.4; 103.8 ± 15.9 g/day). The highest efficiency of N utilization at the level of 31.1 ± 1.4 % was confirmed at a CP content of 150-170 g/kg dry matter of TMR. The evaluation of direct regression dependence between the analysed CP content in TMR and analysed parameters of N transformation in individual farms was confirmed a significant relationship in CP and NH3 content (r = 0.641), CP and urea in the blood (r = 0.689) resp. CP and excretion of N in urine (r = 0.600). Direct relation was confirmed by the analysed NH3 content in the rumen and the urea content in the blood (r = 0.795), and urea in the milk (r = 0.786), as well as the urea content in the blood in relation to the urea in the milk (r = 0.767). The obtained results confirm the suitability of the use of the monitored markers to assess the level of protein nutrition and the environmental load at the farm.

Effect of protein nutrition on bone strength and incidence of osteochondrosis in gilts

Leg-weakness in female breeding pigs has serious implications both in terms of economics and welfare, accounting for up to 0.2 of first litter gilt cullings at an estimated cost to the UK pig industry of up to £3.0 million (Douglas, 1992), with the principal predisposing cause in the growing pig being osteochondrosis. It has been reported that selection for increased lean tissue growth rate and increased growth rate accompanied by ad libitum feeding of diets with high energy and nutrient concentration may increase the incidence of osteochondrosis and leg- weakness (Jorgensen and Sorensen, 1998), although evidence is largely equivocal. The effect of protein level in the diet is uncertain. Although both high and low levels of dietary protein lead to bone growth failure and fracture in human studies ( Reid and New, 1997), protein level has not been found to affect osteochondrosis in pigs (Jorgensen, 1995), thus the aim of the current study was to assess further the effect of protein nutrition on leg weakness in gilts.

Effect of long and short-term protein nutrition on the metabolic status, body composition and reproductive performance of gilts

Reproductive failure is a source of major economic loss to the UK pig industry, accounting for 0.5 of all first parity gilt cullings (MLC Pig Year Book, 1995). Previous research (Cameron et al, 1999) has shown that rearing gilts on a diet formulated to support maximal protein deposition has beneficial effects on ovulation rate at 3rd oestrus. The aim of the current experiment was to develop further the previous model to assess long and short-term effects of protein nutrition on reproductive performance, body composition and metabolic status.

Effect of protein nutrition on insulin-like growth factor-I (IGF-I) receptor in various tissues of rats.

The effects of protein nutrition on insulin-like growth factor-I (IGF-I) receptor in various tissues of rats were investigated. Northern blot and dot blot hybridization analyses were performed using RNA from testis, heart, lung, intestine, stomach, kidney, and brain of rats fed on a 12% casein diet, on a 12% gluten diet which was marginally deficient in lysine and threonine, or on a protein-free diet. The mRNA content of IGF-I receptor in the testis and heart of the rats fed on the 12% gluten and protein-free diets was significantly larger than those of the rats fed on the 12% casein diet. Whereas in other tissues examined, IGF-I receptor mRNA content did not change significantly under the different nutritional conditions. The amount of IGF-I receptor in these tissues and the affinity to IGF-I were determined by measuring the amount of 125I-labelled-IGF-I bound to solubilized IGF-I receptor. The affinity of IGF-I receptor to IGF-I in each tissue under the various nutritional conditions did not show any marked differences. The number of receptors did not change in the testis, lung, intestine, brain or kidney; possibly increased in stomach of the rats fed on the 12% gluten or protein-free diet; and slightly decreased in heart of the rats fed on the 12% gluten diet compared with that of the rats fed on the 12% casein diet. These results indicate that the synthesis of IGF-I receptor is regulated in a distinctive way in each tissue in response to protein nutrition, and suggest that the regulation may have some physiological meaning in signal transmission of IGF-I. The amount of IGF-I receptor, however, was relatively constant in most tissues. Because the plasma IGF-I and IGF-binding protein concentrations change dramatically under different nutritional conditions, we conclude that concentrations of plasma IGF-I and IGF-binding proteins may mainly regulate the IGF-I action in tissues in response to protein nutrition.

Effect of protein nutrition on ammonia emission from a cubicle house for dairy cattle

The effect of protein nutrition on the urinary concentration of urea and subsequent emission of ammonia into the atmosphere was studied using a mechanically ventilated cubicle house containing 34 lactating dairy cows (cross bred Holstein Friesian and Dutch Friesian). Two silage-based diets with different amounts of rumen-degradable protein balance (OEB), were alternately fed during six 3-week periods. Diet L contained a small amount of OEB and resulted in a 39% lower emission rate, compared with diet H which contained a high amount of OEB. The concentration of urea in the urine samples was 42% lower when feeding diet L compared with diet H. A decrease in urea concentration as a result of a lower OEB could contribute substantially towards diminishing the emission of ammonia from cubicle houses for dairy cattle. L'effet de la nutrition protéique sur la concentration d'urée dans l'urine et l'émission correspondant d'ammoniaque dans l'atmosphère ont été étudiés en utilisant une étable à logettes avec ventilation mécanique, contenant 34 vaches laitières (croisées Holstein). Deux régimes à base d'ensilage avec différents niveaux de protéine dégradable dans le rumen (OEB) ont été distribués en alternance pendant six périodes de trois semaines. Le régime L contenait peu d'OEB et a permis de diminuer de 39% le rythme d'émission, par rapport au régime H qui contenait beaucoup d'OEB. La concentration d'urée dans les échantillons d'urine a été de 42% inférieure en régime L par rapport au régime H. Une diminution de la concentration en urée suite à une diminution de l'OEB pourrait contribuer de façon importante à la diminution de l'émission d'ammoniaque par les étables à logettes des vaches laitières. In einem mechanisch belüfteten Boxenstall, in dem 34 laktierende Milchkühe (Kreuzungen aus Holstein Friesian und Holländischen Schwarzbunten) gehalten wurden, ist der Einfluβ der Proteinernährung auf die Harnstoffkonzentration im Urin und die daraus folgende Ammoniakemission in die Atmosphäre untersucht worden. Zwei auf Silage basierende Rationen mit unterschiedlichem Gehalt an im Pansen abbaubarem Protein (OEB) wurden alternativ während sechs 3-Wochen- Perioden gefüttert. Die Ration L zeichnete sich durch einen geringen Gehalt an OEB aus und hatte eine um 39% geringere Emissionsrate im Vergleich zu der Ration H mit einem hohen Gehalt. Die Konzentration von Harnstoff im Urin war bei der Ration L um 42% geringer im Vergleich zur Ration H. Eine Reduzierung der Harnstoffkonzentration im Ergebnis einer geringeren Menge an im Pansen abbaubarem Protein könnte substantiell zur Verringerung der Emission von Ammoniak in Boxenställen für Milchkühe beitragen.

Effect of protein nutrition on the mRNA content of insulin-like growth factor-binding protein-1 in liver and kidney of rats.

Effect of quantity and nutritional quality of dietary proteins on the content of mRNA of insulin-like growth factor-binding protein-1 (IGFBP-1) was studied in rat liver and kidney. IGFBP-1 mRNA content per unit RNA increased in liver and kidney of rats fed on a protein-free diet and in those of fasted rats compared with that in the rats fed on a casein diet. When rats were given a gluten diet for 7 d, IGFBP-1 mRNA content in liver did not change significantly but that in kidney increased considerably compared with that in those organs of the rats fed on the casein diet. Because IGFBP-1 mRNA has been demonstrated both in liver parenchymal and non-parenchymal cells (Takenaka et al. 1991), the effect of the protein-free diet on these two types of cells has been studied. An increase in IGFBP-1 mRNA content under protein deprivation was observed in both liver parenchymal and non-parenchymal cells, suggesting that these two types of cells are regulated in a similar mode as far as IGFBP-1 mRNA content is concerned. The physiological and nutritional significance of the previously stated results on protein anabolism are discussed when considered together with our previous observations on the plasma concentrations of IGF-1 (Takahashi et al. 1990) and IGFBP (Umezawa et al. 1991) and insulin-like growth factor-1 mRNA content in liver (Miura et al. 1991).

Factors limiting the intake of feed by sheep. 13. Voluntary roughage consumption in late pregnancy and early lactation in relation to protein nutrition

Studies were made of (i) the effect of protein nutrition on voluntary roughage consumption in late pregnancy and early lactation, and (ii) the effect of pregnancy on the voluntary consumption of a high protein ground mixture of roughages and concentrates. The three roughage diets used were based on wheaten hay, a mixture of wheaten and lucerne hays and wheaten straw. In late pregnancy, voluntary consumption varied with roughage quality being highest with the wheaten hay diet and lowest with the straw diet. The provision of protein supplements decreased the consumption of wheaten hay diet (-6%), increased the consumption of mixed hay diet during days 31-18 pre-partum (+ 5%), but not at other times, and increased straw diet consumption (+ 17%). The intake of the high protein ground diet was not affected by pregnancy until about day 21 pre-partum, after which it declined at c. 0.9% per day. In early lactation, protein supplement decreased the consumption of wheaten hay diet (-6%), but had no effect on the consumption of mixed hay diet. It was concluded that (i) roughages of comparatively low protein value may provide adequate protein for the expression of maximum voluntary roughage consumption in late pregnancy and early lactation, (ii) feed intake regulation in late pregnancy could not be based solely on physical limitations, on energy metabolism considerations or on hormonal responses, and (iii) changes in the metabolism of maternal adipose tissue in late pregnancy could play a role in the intake regulation.

Effect of protein nutrition throughout gestation and lactation on growth, morbidity and life span of rat progeny.

Thirteen Fischer strain rats were divided randomly into 3 groups soon after became pregnant and fed a 10%, 18%, or 36% casein diet throughout pregnancy and lactation. At weaning, female pups from the dams were divided into 3 further groups which were fed throughout life 10%, 18%, or 36% casein diet. The animals were weighed regularly and given a full autopsy after death. DNA was determined in the cerebrum and cerebellum of progeny at 7, 15 and 50 weeks of age respectively. The level of protein intake of the dams did not affect the litter-size, but did affect the body weight of pups at weaning. When fed a high protein diet after weaning, pups from dams fed a low protein diet weighed less throughout life than those from dams fed a high protein diet. A similar effect of protein intake was observed on the tail length. Pups of dams fed a low protein diet ate a larger amount of diet per unit body weight after weaning than those of dams fed at a high level of protein. Pups at 7, 15, and 50 weeks of age respectively from dams fed 10% casein diet had a lighter cerebrum and cerebellum than pups of the same ages from dams fed respectively 18% and 36% casein diet. They also had less total DNA in the cerebrum and cerebellum than the latter. At the ages of 1 and 2 years respectively, the survival rates of rats fed the same diet as their mothers tended to be greater than those of rats fed diet different from that of their mothers. They also tended to live longer than the latter: 4 of 60 rats lived for over 1,000 days, and 3 of these were fed the same diet as that of their mothers. Lesions observed at death did not differ in different groups. However, the incidence of lesions of the kidney and the number of tumors seemed to be greater in groups fed a high protein diet.

Effects of protein nutrition on Pb, Ca, and P contents in hard tissues of lead-administered rats

The accumulation of lead, harmful to the living body, in hard tissues was investigated in relation to nutrition. An examination was also made of the quantitative changes in Ca and P, measureing the constituent elements of hard tissues after lead administration. Lead-administered rats were fed on 5%, 18%, and 30% protein diets for 4 weeks. Lead accumulation was largest in the group of rats fed on the 5% protein diet and was more remarkable in young rats than in adults. Quantitative changes in Ca and P were observed mainly in the femurs.

Effects of protein nutrition in young pigs on developmental changes in the body and sekeletal muscles during growth.

Two experiments were conducted with growing pigs killed at various predetermined weights. Effects of protein level and quality of chemical body composition and chemical and physical composition of selected muscles were studied. In Experiment 1, pigs were fed either 10 or 20% crude protein of good quality and identical amino acid ratios. The pigs were killed at weights that represented equal logrithmic spacing of their estimated lean mass (moisture plus protein). At similar lean masses, the empty bodies of pigs fed a diet of 10% protein contained considerably more ether extract than those of pigs fed a 20% protein diet, but, as predicted, the two groups had similar amounts of moisture and protein. Analyses of a rectus femoris muscle revealed that weight, average fiber diameter, DNA, RNA, protein, moisture, protein:DNA and RNA:DNA increased with increasing lean mass at slaughter. Only RNA, RNA:DNA and moisture were affected by protein level; RNA and RNA:DNA ratio being greatest and moisture least in pigs fed the 20% protein diet. In experiment 2, pigs were fed the same 10 and 20% protein diets of experiment 1, and a third group was fed a 20% protein diet with poor amino acid balance (poor protein quality). As in Experiment 1, empty bodies of pigs fed good quality protein at 10 and 20% levels had predictible contents of moisture and protein; these components, however, were overestimated for pigs fed the diet with 20% protein of poor quality. Analysis of a M. longissimus from each pig showed that weight, average fiber diameter, DNA, RNA, protein, moisture, protein:DNA and RNA:DNA increased as the pigs grew. RNA, protein:DNA and RNA:DNA were greater in the muscles of pigs fed 20% protein of good quality than in those of pigs fed 10% protein of good quality. RNA, protein, moisture and RNA:DNA ratio were greater in the M. longissimus of pigs fed 20% protein of good quality than in those of pigs fed 20% protein of poor quality. Estimates of numbers of nuclei (NN), muscle fiber cross-sectional area (CSA) and muscle weight (WT) were indicative of expected mathematical relationships. These expected relationships define an expanding cylinder, in which a constant ratio is maintained between length and diameter and there is a direct relationship between CSA and NN. Expected regression coefficients for log CSA on log WT, log NN on log WT and log NN on log CSA are .67, .67 and 1.0, respectively. Protein level and quality did not influence these relationships in either the rectus femoris or the M. longissimus

The effect of protein nutrition between 5–5 and 20 kg live weight on the subsequent performance and carcass quality of pigs

ABSTRACTThirty male pigs weaned at 5·5 kg were used to determine the effect of diets with 164, 192 and 219 g/kg crude protein offered ad libitum to 20 kg live weight on performance and carcass characteristics during this initial phase of growth and during the period subsequent to 20 kg live weight when all pigs were fed on a diet with 181 g/kg crude protein in restrictive amounts. Between 5·5 and 20 kg live weight, pigs offered the diet with 164 g/kg crude protein grew significantly more slowly and had a significantly poorer food conversion ratio than pigs offered the two higher protein diets. Both linear fat measurement and the proportion of ether extractable material in the carcass at 20 kg live weight decreased significantly with each increase in dietary protein. Pigs offered the 164 g/kg protein diet during the initial treatment period tended to grow faster subsequent to 20 kg and during the live-weight period 20 to 45 kg had a significantly lower food conversion ratio than pigs previously offered the two higher protein diets. Over the entire production period, 5·5 to 70 kg, there were no significant differences between treatments. Likewise there were no significant differences in carcass quality parameters between treatments at 70 kg live weight.

The effect of protein nutrition on host and tumor metabolism

Since the introduction of intravenous hyperalimentation (IVH) as a nutritional adjunct in multimodal cancer therapy (X), the risk of providing nutrient substrates for more rapid tumor growth has been a concern of those who use IVH to rehabilitate malnourished cancer patients nutritionally. Because of the technical difficulties in studying glucose and amino acid utilization in cancer patients, an experimental model was designed to simulate the nutritional problems encountered in cachectic cancer patients. Tumor-bearing rats were protein depleted with a protein-free diet, and then randomized into three groups which either continued on the protein-free diet, resumed a regular protein diet, or received intravenous hyperalimentation. By manipulating the dietary protein intake, the effects of protein restriction and repletion on host and tumor metabolism could be compared and related to the clinical situation in which hyperalimentation is used to replete malnourished cancer patients nutritionally. Host and tumor metabolism were evaluated by measuring the activity of three important enzymes that control glucose production and specific amino acid degradation. Fructose 1,6-diphosphatase (FDPase, EC 3.1.3.11) is considered one of the rate-limiting enzymes in the gluconeogenic pathway because of its slow kinetics and irreversible catalytic action (25). Glutamate -pyruvate transaminate (GPT, L-alanine:Z

Protein nutrition and aging.

Twenty-four female rats consisting of 6 sets of litters were used for the experiment. After weaning, rats were divided into 4 groups and fed with 10, 18, 27 and 36% casein diet. Effect of protein nutrition on aging was examined from the anthropometric and biochemical viewpoint. The difference of growth in body weight, and that of the urinary excretion of creatinine and 17-ketosteroids observed in the early period of growing disappeared by the end of growth period. From 1 year after birth, serum alkaline phosphatase activity and serum cholesterol were also measured. However, effect of protein nutrition on these parameters was not clear due to the scatter of data. The difference in diet did not affect life span in the present experiments, but the effect of the variance of litters on it seemed to be significant between the rats fed 18% casein diet and those fed 10% casein diet. Rats fed high-protein diet had a great number of lesions in the kidney and hypophysis, and often an incidence of tumors.

Effect of Protein Nutrition on Growth, Longevity and Incidence of Lesions in the Rat

Six similar experiments were conducted with a total of 208 female rats to determine the effect of the level (10, 18, 27, and 36%) of protein intake on growth. The effect of level of protein intake on longevity was also observed in 160 of the rats. All rats were fed an 18% casein diet for 1 week after weaning and then were separated into three or four dietary groups. Littermates were evenly distributed in the different groups. The increases in both tail length and body weight of rats fed a 10% casein diet were generally less than those of the rats fed the higher levels of protein, especially in weeks 8 to 10 after birth. This difference gradually decreased and became insignificant by the end of the growth period. The effect of level of protein on the biochemical mea sures (urinary excretion of creatinine, hydroxyproline and 17-ketosteroids, and the serum alkaline phosphatase activity) observed in the early period of growth among the four groups became obscure by the end of the growth period. In brief, the growth rate varied directly with the protein intake in the early period, but eventually the differences observed among the groups became insignificant. However, the effect of variance of litters was equal to or greater than that of difference in diet. Diet and the differences among litters had no effect on longevity. The number of lesions observed at death did not differ among the groups. In one experiment, however, the incidence of lesions in the spleen and the number of mammary tumors seemed to be greater in the groups fed a high protein diet. J. Nutr. 104: 1576-1583, 1974.

Effects of dietary deficiencies of energy, protein and calcium on the pregnant ewe: V. Chemical analyses and histological examination of some individual bones

SUMMARYThe effects of low protein and low Ca intakes during pregnancy on the chemical composition and histological appearance of selected bones of ewes and lambs is reported. Twenty-eight 6½-year-old Blackface ewes were used in a 2 x 2 experiment in which semi-purified diets containing 11·8 and 6·0% crude protein and 1·2 and 0·11% Ca in the dry matter were offered in amounts designed to induce a level of undernutrition typical of that experienced by hill sheep in winter. In addition, six sheep were killed in early pregnancy as controls, and a further six were offered, during pregnancy, a conventional diet containing 16% crude protein and 1·9% Ca in the dry matter at levels which prevented energy undernutrition. Ewes and lambs were killed at parturition and the tibias, 3rd ribs and 3rd and 4th lumbar vertebrae removed for chemical and histological examination.The degree of mineralization of the organic matrix (ash:organic-matter ratio) of the bones at the beginning of pregnancy was poor and it increased in all groups during pregnancy largely irrespective of protein or Ca intake, but especially in the wellnourished sheep. The density of ash in the whole bone (ash:volume ratio) increased in the well-nourished and high-protein groups but did not change in the low-protein groups. These differences were attributable to the effect of protein nutrition on the density of the bone organic matrix (organic matter:volume ratio). Matrix density of the bones of the well-nourished groups increased while that of the low-protein groups decreased.The histological data essentially confirmed this picture and showed that trabecular or cancellous bone from the tibial head and vertebrae of the low-protein and to a lesser extent the high-protein sheep was porotic, but microscopic assessment conflicted with the chemical findings in that histologically Ca intake appeared to affect bone quality in the vertebrae.There was considerable variation in the histology of individual lamb bones which was independent of maternal nutritional experiences, but the overall size of the bones was determined by maternal protein nutrition.

Effect of Protein Nutrition on Growth and Life Span in the Rat

The effect of the amount and composition of protein (10, 18, and 27% casein and pure amino acid mixture diet) on growth and life span of rats was examined by using littermate females. Tail length and body weight were measured, and estrus cycle was examined by a smear test. In addition, body constituents were determined several times during the growing period. Tail length and body weight on the rats fed 10% casein diet were less than those of rats fed 18% or 27% casein, or an amino acid mixture early in the growth period. However, the difference seen among them became insignificant later in the growth period, except in the case of 27% casein-fed rats. It was found that both the amount of protein intake and variance of littermates, which refer to litters of different mothers, had statistically significant effect on growth, especially in the earlier part of growth. Estrus cycle appeared later in the 10% casein-fed rats and seemed to be irregular longer, as compared with that of rats in other groups. With respect to body constituents, concentration of water was higher and that of fat was lower soon after weaning, and then the relative water content decreased and the fat increased during the growth period, irrespective of the difference in diet. From the results obtained in the present experiments, it was concluded that the effect of difference in diet, containing 10 or 18% casein, or an amino acid mixture corresponding to 18% casein, on life span was not significant. The variance of littermates was relatively great but, in the case of 27% casein diet, both the difference in diet and the variance of littermates had no statistically significant effect on life span. The present experiment indicates that an amino acid diet, when properly composed, will support growth and life span closely approaching that obtained with casein.

EFFECT OF PROTEIN NUTRITION ON LEUKOCYTE MOBILIZATION.

SummaryRats made less resistant to anthrax by means of a gluten diet have been studied as to their ability to elicit an adequate phagocytic response. When followed by the Rebuck technique, the gluten-fed animals do not sustain a total leukocyte response as do the controls. In addition, the relative number of monocytes is reduced by more than 50%. When followed by the ability to mobilize leukocytes in response to an intraperitoneal irritant, the less resistant group responded with a decreased rate as well as decreased numbers of leukocytes.