Maternal dietary supplementation with ferrous N-carbamylglycinate chelate affects sow reproductive performance and iron status of neonatal piglets.

Iron-deficiency anemia is a public health concern that frequently occurs in pregnant mammals and neonatal offspring. Ferrous N-carbamylglycinate chelate (Fe-CGly) is a newly designed iron fortifier with proven effects in iron-deficient rats and weanling piglets. However, the effects of this new compound on pregnant mammals are unknown. Therefore, this experiment was conducted to evaluate the effects of Fe-CGly on sow reproductive performance and iron status of both sows and neonatal piglets. A total of 40 large-white sows after second parity were randomly assigned to two groups (n=20). They were receiving a diet including 80 mg Fe/kg as FeSO4 or Fe-CGly, respectively, from day 85 of gestation to parturition. The serum (day 110 of pregnancy) and placentas of sows were sampled. Litter size, mean weight of live born piglets, birth (live) litter weight, number of live born piglets, and the number of still-born piglets, mummies, and weak-born piglets were recorded. Once delivered, eight litters were randomly selected from the 20 litters per treatment, and one new-born male piglet (1.503±0.142 kg) from each selected litter was slaughtered within 3 h after birth from the selected litters, without colostrum ingestion. The serum, longissimus muscle, liver and kidneys of the piglets were collected. The iron status of the serum samples and the messenger RNA level of iron-related genes in the placenta, liver and kidney were analyzed. The results showed that litter weight of live born piglets was higher (P=0.030) in the Fe-CGly group (19.86 kg) than in the FeSO4 group (17.34 kg). Fe-CGly significantly increased placental iron concentration (P<0.05) of sows. It also significantly increased iron saturation and reduced the total iron-binding capacity of piglets (P<0.05) at birth. However, the results revealed that supplementation of Fe-CGly in sows reduced liver and kidney iron concentration of neonatal piglets (P<0.05), indicating decreased iron storage. In addition, the concentration of iron in the colostrum was not significantly changed. Therefore, the present results suggested that replacement of maternal FeSO4 supplement with Fe-CGly in the late-gestating period for sows could improve litter birth weight, probably via enhanced iron transportation in the placenta.

Short-term supplementation of isocaloric meals with L-tryptophan affects pig growth.

L-Tryptophan (Trp) and some of its metabolites regulate the circadian rhythm in mammals. We aimed to investigate the effects of short-term supplementation of Trp in isocaloric meals on growth performance using the parameters of multiple blood biomarkers and free amino acids in growing pigs. A total of 32 Landrace × Yorkshire barrows with a mean body weight of 8.64 (±1.13) kg were randomly assigned to four groups and then fed with various concentrations of Trp diets daily. Our results showed that sequential supplementation of different concentrations of Trp in isocaloric meals decreased the feed:gain (F:G) ratio (P = 0.079) and plasma urea and albumin (P = 0.019), whereas the level of total protein did not. Among the essential and conditionally essential amino acids, the concentrations of histidine, isoleucine, proline, threonine, arginine, and valine in the plasma decreased (P < 0.05), whereas the concentrations of Trp, glycine, serine, and methionine increased (P < 0.01). In addition, concentrations of branched chain amino acids also significantly decreased (P = 0.004), while the rate of conversion of Trp to branched chain amino acids increased (P < 0.001). Taken together, we show that administration of a high concentration of Trp in breakfast with decreasing concentrations of Trp in lunch and dinner positively affected feed utilization and improved feed efficiency, at least in part, through the optimization of amino acid interconversions and nitrogen utilization.

Regulation in free amino acid profile and protein synthesis pathway of growing pig skeletal muscles by low-protein diets for different time periods.

The objective of the study was to explore the extent to which the dietary CP level can be reduced for maintaining muscle protein deposition in growing pigs as well as the related mechanism and whether the response to dietary protein restriction is diversely modified throughout the 2 trial periods. A total of 36 pigs (9.57 ± 0.64 kg initial BW) were individually penned and fed 1 of 3 diets for 10 or 25 d. During each period, the diets contained 20, 17, and 14% CP, respectively. Both the 17% CP diet and the 14% CP diet were supplemented with Lys, Met, Thr, and Trp to provide the same total concentrations as those in the 20% CP diet. Results showed that feeding the 14% CP diet for 10 or 25 d seriously impaired ( < 0.05) growth performance of the pigs compared with those fed the 20 or 17% CP diets. Pigs fed the 20% CP diet for 25 d had a higher ( < 0.05) serum content of urea nitrogen than those fed the 17 and 14% CP diets. In addition, the free AA (FAA) profile in skeletal muscle of the pigs was evidently changed ( < 0.05) by the low-protein diets for 25 d; of note, the 14% CP diet increased ( < 0.05) the size of muscle FAA pool compared with the 20% CP diet. Meanwhile, on d 25, reducing dietary CP levels also influenced ( < 0.05) mRNA levels of specific AA transceptors expressed in skeletal muscle, especially revealing the striking differences between the 14 and 20% CP diet-fed pigs. Most importantly, we observed a globally decreased ( < 0.05) activation of the mammalian target of rapamycin complex 1 (mTORC1) pathway in skeletal muscle of pigs fed the 14% CP diet, whereas only partial inhibition was observed for those fed the 17% CP diet compared with those fed the 20% CP diet. However, feeding the low-protein diets for 10 d had minimal effects on serum parameters, muscle FAA profile, and muscle mTORC1 pathway of the pigs. Taken together, our results indicate that supplementing with limiting AA to the 14% CP diet is not highly effective for the pigs in restoring protein synthesis and muscle growth, whereas the 17% CP diet likely maintains the pigs' muscle mass, which were regulated, at least in part, by mediating AA transceptors expression, FAA profile, and activation of the mTORC1 pathway.

Chemical composition of yak colostrum and transient milk.

The objective of this study was to assess the changes in the chemical composition of yak colostrum and transient milk. Samples were collected from 12 yaks on days 1, 2, 3, 4, 5, 6 and 7 post-partum (PP). The gross composition, nitrogen fraction distribution, amino acid (AA) profile and fatty acid (FA) profile were analysed. All the components decreased rapidly during the first 3 days except lactose which increased. The ratio of whey protein to casein protein decreased from 46:54 to 17:83 during the first 7 days PP. The content of all the AAs decreased, while the percentages of eight essential AAs in protein of samples increased during the study period. Monounsaturated FAs and polyunsaturated FAs decreased in the first 7 days PP, whereas saturated FAs increased. In conclusion, the changes in chemical composition were remarkable during the first 3 days. The slight variations, happened during the transient period, are not negligible, which also should be taken into account in the development of yak colostrum supplements.

Effects of dietary supplementation of quercetin on performance, egg quality, cecal microflora populations, and antioxidant status in laying hens.

Plant polyphenols, especially flavonoids, are of great interest due to their wide range of biological activities. Quercetin, a ubiquitous flavonoid, is known to have antioxidant and antibacterial effects. In this study, we investigated the effect of quercetin on performance, egg quality, cecal microflora populations, and antioxidant status in laying hens. Two hundred forty 28-wk-old Hessian laying hens, with an average laying rate of lay 85% at the start, were randomly allotted to 4 treatments and fed 1 of 4 diets (negative control, 0.2, 0.4, and 0.6 g of quercetin/kg of diet) for 8 wk. Layer performance responses, egg quality parameters, cecal microflora populations and antioxidant status were measured at the end of the experiment. Results showed that feed conversion decreased as the quercetin level increased. Laying rate had a quadratic correlation with the level of quercetin (P = 0.056) and was maximized by the supplementation level of 0.2 g/kg of diet. However, no significant quercetin effect was observed on egg quality. Regression analysis showed that the population of total aerobes and coliforms decreased and the population of Bifidobacteria increased as the level of quercetin increased. Regression analysis also showed the activities of Cu-Zn-superoxide dismutase increased as the level of quercetin increased (P < 0.05). Results of the study suggest that the appropriate level of supplementation is 0.367 to 0.369 g of quercetin/kg of feed based on the improvement of laying rate (with 88.55 as maximum value) and feed conversion (with 2.0725 as minimum value). Our observations provided further evidence that dietary supplementation of quercetin improved performance by modulation of intestinal environment and liver superoxide dismutase content in laying hens. Quercetin has the potential as functional feed additive in animal production.

Effect of quercetin on performance and egg quality during the late laying period of hens.

1. At the end of the peak laying period for fowl, both performance and egg quality decrease markedly. Counteracting either or both of these could, therefore, have significant positive economic implications. Quercetin, a typical representative of the flavonol compounds, has a variety of biological functions. However, there are no reported findings on its use as a feed additive. 2. In this study, we investigated the effects of quercetin on laying rate, egg quality and blood traits associated with egg quality in laying hens (Hessain) during the late laying period and explored the possibility of using quercetin as a functional feed additive. 3. The laying hens (n = 240; 39 weeks old) were randomly assigned to 4 treatments consisting of 6 replicates (n = 10) and were fed with diets containing quercetin at 0, 0.2, 0.4 or 0.6 g/kg. 4. Results showed that laying rate was increased and feed-egg ratio was decreased significantly by 0.2 and 0.4 g/kg quercetin. Compared with controls, Haugh unit, eggshell strength, eggshell thickness and yolk protein were increased, but yolk cholesterol was decreased by quercetin. 5. In conclusion, quercetin was beneficial in improving performance and egg quality. The recommended concentration of quercetin is 0.4 g/kg of the basal diet. At this concentration, increased laying rate, improved egg quality and reduced yolk cholesterol can be expected.

Fatty acid profile of yak milk from the Qinghai-Tibetan Plateau in different seasons and for different parities.

Yaks are the most important grazing livestock for milk production on the Qinghai-Tibetan plateau because these animals are adapted to the high elevations and extremes of cold and can graze throughout the year. In the present study, 30 yaks were selected and the fatty acid (FA) profile of yak milk at different seasons and parities was investigated using gas chromatography. The concentrations of cis-9 C18:1, cis-11 C18:1, cis-9,trans-11 C18:2, and C18:3 n-3 in yak milk were higher in summer (25.26, 1.50, 1.46, and 0.33 g/100 g of total FA, respectively) than in winter (22.17, 0.77, 1.27, and 0.28 g/100 g of total FA, respectively). The contents of monounsaturated and polyunsaturated FA in milk fat of multiparous (parities 2 to 5) yaks (31.61 and 4.20 g/100 g of total FA, respectively) were higher than those in primiparous yaks (29.61 and 3.80 g/100g of total FA, respectively). These results suggest (1) that the potential exists to improve the FA composition of yak milk by developing local supplement resources during the winter and (2) that multiparous yaks have a more favorable FA profile than primiparous yaks.

Hemodialysis-related pruritus: a double-blind, placebo-controlled, crossover study of capsaicin 0.025% cream.

Pruritus is a significant symptom among patients receiving hemodialysis. However, its underlying mechanisms remain obscure. Substance P, a neuropeptide, has been implicated in the mediation of pain and some itch sensations. Local application of capsaicin depletes the peripheral neurons of substance P and may block the conduction of pain or pruritus. This study aims to assess the efficacy and safety of capsaicin 0.025% cream in the treatment of hemodialysis-related pruritus and to further explore the underlying pathomechanism. Nineteen hemodialysis patients with idiopathic, moderate (n = 5) to severe (n = 14) pruritus were examined in a double-blind, placebo-controlled, crossover study and 17 of them completed the study. Topical agent of capsaicin or placebo base cream was applied to localized areas of pruritus 4 times a day. The severity of pruritus and treatment-related side effects (cutaneous burning/stinging sensations, dryness, or erythema) were evaluated weekly. The results showed (1) that 14 of 17 patients reported marked relief and 5 of these 14 patients had complete remission of pruritus during capsaicin treatment (Wilcoxon signed-ranks test, 2p < 0.001); (2) capsaicin was significantly more effective than placebo (Mann-Whitney rank sum test, 2p < 0.001) and a prolonged antipruritic effect was observed 8 weeks posttreatment; (3) no serious side effects were noted during the study and (4) there were no significant changes in serum concentrations of albumin, calcium, phosphorus, alkaline phosphatase, or intact parathyroid hormone during the treatment with either capsaicin or placebo. In summary, the present study indicates indirectly that idiopathic pruritus in some patients on maintenance hemodialysis may be transmitted by substance P from the peripheral sensory neurons to the central nervous system. Topical capsaicin with the unique pharmacological effect is demonstrated to markedly improve the pruritus of these patients.