Effects of dietary betaine supplementation subjected to heat stress on milk performances and physiology indices in dairy cow.

This study aimed to determine whether feeding betaine to cows elevates their production performance during summer heat stress. Thirty-two lactating Holstein cows were randomly divided into 4 groups: the control group, which received a total mixed ration (TMR), and 3 experimental groups that received TMR blended with 10 g/day (group I), 15 g/day (group II), and 20 g/day (group III) betaine for 8 weeks. Milk and blood were sampled throughout the experimental period. The average maximum and minimum air temperatures were 28.3 and 24.1°C, respectively. The average temperature-humidity index was 78.6 units. The results showed that feeding betaine to cows increased feed intake, milk yield, milk lactose, milk protein, plasma cortisol, glutathione peroxidase, superoxide dismutase, and malondialdehyde levels (P<0.05); however, it caused HSP70 levels to decrease (P<0.05). The milk performance of group II was significantly affected. These results indicate that supplementing betaine to the diet of dairy cows increases their milk performance and improves their antioxidant capacity; these processes help relieve the cow from heat stress. In conclusion, supplementing dairy cows with 15 g/day betaine generated the most positive influence on performance and productivity, and hence caused the greatest reduction in heat stress.

Effects of different dietary intake on mRNA levels of MSTN, IGF-I, and IGF-II in the skeletal muscle of Dorper and Hu sheep hybrid F1 rams.

MSTN, IGF-І(insulin-like growth factor-І) and IGF-II (insulin-like growth factor-II) regulate skeletal muscle growth. This study investigated the effects of different dietary intake levels on skeletal muscles. Sheep was randomly assigned to 3 feeding groups: 1) the maintenance diet (M), 2) 1.4 x the maintenance diet (1.4M), and 3) 2.15 x the maintenance diet (2.15M). Before slaughtering the animals, blood samples were collected to measure plasma urea, growth hormone, and insulin concentrations. After slaughtering, the longissimus dorsi, semitendinosus, semimembranosus, gastrocnemius, soleus, and chest muscle were removed to record various parameters, including the mRNA expression levels of MSTN and IGFs, in addition to skeletal muscle fiber diameter and cross-sectional area. The result showed that as dietary intake improved, the mRNA expression levels of MSTN and IGF-II decreased, whereas IGF-Іexpression increased. The mRNA expression levels of MSTN and IGFs were significantly different in the same skeletal muscle under different dietary intake. The skeletal muscle fiber diameter and cross-sectional area increased with greater dietary intake, as observed for the mRNA expression of IGF-І; however, it contrasted to that observed for the mRNA expression of MSTN and IGF-II. In conclusion, dietary intake levels have a certain influence on MSTN and IGFs mRNA expression levels, in addition to skeletal muscle fiber diameter and cross-sectional area. This study contributes valuable information for enhancing the molecular-based breeding of sheep.

Endocrine and molecular regulation mechanisms of the reproductive system of Hungarian White geese investigated under two artificial photoperiodic programs.

Hungarian White geese are regarded as good producers of meat, eggs, and feathers, but specific lighting schedules are required to improve their egg-laying performance. This study reveals the neuroendocrine regulatory mechanisms that govern the reproductive activities and egg-laying performances of Hungarian White geese. The results indicated that increasing the daily photoperiod from a short 8 h period to either 11 h or 14 h initiated reproduction. Egg-laying rates increased faster in the 14 h group, peaking (48.2%) on day 33 as compared to the peak (52.67%) reached on day 53 in the 11 h group. Changes to the plasma estradiol and progesterone concentrations produced similar patterns in the two groups. In the hypothalamus, OPN5, Dio2, c-Fos, and GnRH-I expression levels showed similar sequential increases and decreases. Changes in GnIH and VIP expression levels were the opposite to those of GnRH-I, but the levels peaked earlier under the 14 h photoperiod conditions. Pituitary LH beta and FSH beta expression levels increased at slower rates but remained significantly higher in the 11 h group than in the 14 h group. However, pituitary PRL expression increased considerably earlier and was higher in 14 h geese than in 11 h geese, which was opposite to the observed egg-laying rate patterns. An increase from a short to a relatively long photoperiod (11 h) regulated the neuroendocrine system and led to reproductive activities being sustained for a longer period, which resulted in high egg-laying performances.

Creating leptin-like biofunctions by active immunization against chicken leptin receptor in growing chickens.

In this study, immunization against chicken leptin receptor (cLEPR) extracellular domain (ECD) was applied to investigate leptin regulation and LEPR biofunction in growing chicken pullets. A recombinant protein (cLEPR ECD) based on the cLEPR complemenary DNA sequence corresponding to the 582nd to 796th amino acid residues of cLEPR mature peptide was prepared and used as antigen. Immunization against cLEPR ECD in growing chickens increased anti-cLEPR ECD antibody titers in blood, enhanced proportions of phosphorylated janus kinase 2 (JAK2) and served as signal transducer and activator of transcription 3 (STAT3) protein in liver tissue. Chicken live weight gain and abdominal fat mass were significantly decreased (P < 0.05), but feed intake was stimulated by cLEPR ECD immunization (P < 0.05). The treatment also upregulated the gene expression levels of lepR, AMP-activated protein kinase (AMPK), acetyl CoA carboxylase-2 (ACC2), and uncoupling protein 3 (UCP3) in liver, abdominal fat, and breast muscle (P < 0.05) but decreased fasn expression levels (P < 0.01). Apart from that of lepR, the expression of appetite-regulating genes, such as orexigenic genes, agouti-related peptide (AgRP) and neuropeptide Y (NPY), were upregulated (P < 0.01), whereas the anorexigenic gene proopiomelanocortin (POMC) was downregulated in the hypothalamic tissue of cLEPR-immunized pullets (P < 0.01). Blood concentrations of metabolic molecules, such as glucose, triglycerides, and very-low-density lipoprotein, were significantly decreased in cLEPR-immunized pullets but those of cholesterol, high-density lipoprotein, and low-density lipoprotein increased. These results demonstrate that antibodies to membrane proximal cLEPR ECD enhance cLEPR signal transduction, which stimulates metabolism and reduces fat deposition in chickens.

[A multiple-channel system for synchronous acquisition and analysis of neural electrophysiological signals].

The technique for synchronous electrophysiological recording from multiple single cells has been widely applied, but there is still a shortage of suitable data acquisition and analysis systems to fit electrophysiological equipment made in China or Japan. Recently we have developed an acquisition and analysis system for multiple-channel electrophysiological recording. In this paper, we present the pivotal technique of the system and some examples of applications.

Effect of nutrition on plasma lipid profile and mRNA levels of ovarian genes involved in steroid hormone synthesis in Hu sheep during luteal phase.

Ovarian steroid hormones regulate follicular growth and atresia. This study aims to determine whether key ovarian sterol-regulatory genes are differentially expressed in Hu sheep under different short-term nutritional regimens. Estrus was synchronized using intravaginal progestagen sponges. The ewes were assigned randomly to 3 groups. On d 6 to 12 of their estrous cycle, the control (CON) group received a maintenance diet (1.0×M), the supplemented (SUP) group received 1.5×M, and the restricted (R) group received 0.5×M. On d 7 to 12, blood samples were taken. The sheep were slaughtered at the end of the treatment, and their organs and ovaries were collected. The plasma concentrations of urea (P<0.01), total cholesterol (P<0.01), low-density lipoprotein cholesterol (P<0.01), NEFA (P<0.01), FSH (P<0.05), and estradiol (P<0.05) increased with decreasing dietary intake, whereas plasma triglyceride (P<0.01) and triiodothyronine (T3) concentrations decreased (P<0.05). The ewes in the R group had higher spleen weight and percentage of spleen to BW and lower liver and small intestine weights and percentage of liver/stomach to BW than the SUP group ewes (P<0.05). Nutritional restriction decreased the cytochrome p450 (CYP17A1) and estrogen receptor 1 (ESR1) mRNA expression (P<0.05) and increased the cytochrome p450 aromatase (CYP19A1) mRNA expression (P<0.05) in follicles>2.5 mm. Follicle size affected the mRNA expression of very low density lipoprotein receptor (VLDLR), estrogen receptor 2 (ESR2), FSH receptor (FSHR), CYP17A1, and CYP19A1 (P<0.05). In conclusion, we suggest that a potential mechanism by which short-term negative energy balance inhibits follicular growth may involve responses to disrupted reproductive hormone concentrations and influenced the intrafollicular expression of CYP17A1, CYP19A1, and ESR1. This result may be due to increased plasma urea and lipid concentrations.

Hepatoprotective effect of an immortal human fetal hepatic cell transplantation on CCL(4)-induced acute liver injury in mice.

Hepatocyte transplantation has been widely confirmed in the animal model experiments as an effective method for treatment of fulminant hepatic failure. However, the lack of donor organs remains a major problem. One solution is the development of transplantable hepatocytes. Herein we have transplanted intraperitoneally an established immortalized human fetal hepatic cell line (HL-7702) into CCl(4)-treated mice with acute liver injury to determine whether they provided life-saving metabolic support. The results showed lower levels of blood ammonia and higher content of liver albumin (P < .05) after HL-7702 transplantation versus nontransplanted controls at days 3 and 7. Histologic examination showed the transplantation group to be less affected at day 7 with no difference at day 14. In conclusion, an established immortal human fetal hepatic cell line may be a promising cell source providing life-saving metabolic support as a bioartificial liver device for the treatment of acute liver injury.