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1.
This study was conducted to assess the effects of dietary corn oil and vitamin E supplementation on fatty acid (FA) profiles and abundances of acetyl‐CoA carboxylase (ACC) and Δ9 stearoyl‐CoA desaturase (SCD) mRNA of Hu sheep. Animals were allocated to three dietary treatments: basal and supplemented with 3% corn oil (CNO), or CNO plus 500 mg/kg vitamin E (COE). The experiment lasted for 10 weeks. No differences were observed in growth performance and carcass qualities among the three treatments (P > 0.05). Feeding CNO and COE diets increased polyunsaturated FAs including cis 9 trans 11 conjugated linoleic acid, and decreased saturated FA in longissimus muscle (P < 0.05). The mRNA abundances of ACC and SCD as detected by real‐time PCR were reduced (P < 0.05) in liver and subcutaneous fat by supplementary oil, while the SCD mRNA level in longissimus muscle was also reduced (P < 0.05). Inclusion of vitamin E did not have further effects on mRNA abundances of these two enzymes. It is suggested that dietary corn oil supplementation may reduce FA biosynthesis and influence FA profiles in Hu sheep through decreased expression of both ACC and SCD genes.  相似文献   

2.
Stearoyl‐CoA desaturase (SCD) is an important enzyme in the bovine mammary gland, where it inserts a cis‐double bond at the Δ9 position in a wide range of fatty acids. Investigating SCD expression in the bovine mammary gland generally requires invasive biopsy to obtain mammary tissue. The aim of this study was to evaluate the use of milk somatic cells as a non‐invasive alternative to biopsy for measuring mammary SCD expression in dairy cows. Both milk somatic cells and mammary tissue were collected from 14 Holstein‐Friesian cows and used for analysis of SCD expression by real‐time PCR. The SCD5 mRNA levels in mammary tissue compared with SCD1 were low, and for several milk somatic cell samples, SCD5 expression was even below the limit of detection. A significant relationship was found between SCD1 expression in milk somatic cells and in mammary tissue. In addition, SCD1 expression in milk somatic cells was significantly related to Δ9‐desaturase indices in milk, which are commonly used as an indicator of SCD1 activity within the mammary gland. Our study showed that milk somatic cells can be used as a source of mRNA to study SCD1 expression in dairy cows, offering a non‐invasive alternative to mammary tissue samples obtained by biopsy.  相似文献   

3.
The aim of this study was to investigate the anorectic mechanism of calcitonin gene‐related peptide (CGRP) in rats. Intraperitoneal injection of CGRP (50 μg/kg) resulted in decline (p < 0.05) in the food intake of rats at 0.5, 1, 2 and 4 h in comparison with saline control. Compared with saline‐treated group, the levels of hypothalamic 3′,5′‐cyclic adenosine monophosphate (cAMP) and plasma glucagon were increased (p < 0.05) in CGRP‐treated group, but insulin level was decreased (p < 0.05). No significant changes (p > 0.05) in the plasma leptin were observed between two treatment groups. Calcitonin gene‐related peptide injection down regulated (p < 0.05) both neuropeptide Y (NPY) and melanin‐concentrating hormone (MCH) genes at mRNA levels, but up regulated (p < 0.05) the expression of cholecystokinin (CCK) gene. The correlations analysis showed that food intake was negatively correlated (p < 0.05) with CCK mRNA, cAMP and glucagon levels. Moreover, there existed negative correlations (p < 0.05) between MCH mRNA and glucagon levels, and positive correlations (p < 0.05) between insulin and leptin levels. The results showed that cAMP acting as the second messenger may play a vital role in the anorectic effects of CGRP. Calcitonin gene‐related peptide could stimulate anorexigenic neuropeptides (i.e. CCK) and/or inhibit orexigenic neuropeptides (i.e. NPY and MCH) expression, and ultimately suppressed food intake that was functionally coupled to cAMP/PKA pathway activation.  相似文献   

4.
The regulatory mechanisms underlying food intake in chickens have been a focus of research in recent decades to improve production efficiency when raising chickens. Lines of evidence have revealed that a number of brain‐gut peptides function as a neurotransmitter or peripheral satiety hormone in the regulation of food intake both in mammals and chickens. Glucagon, a 29 amino acid peptide hormone, has long been known to play important roles in maintaining glucose homeostasis in mammals and birds. However, the glucagon gene encodes various peptides that are produced by tissue‐specific proglucagon processing: glucagon is produced in the pancreas, whereas oxyntomodulin (OXM), glucagon‐like peptide (GLP)‐1 and GLP‐2 are produced in the intestine and brain. Better understanding of the roles of these peptides in the regulation of energy homeostasis has led to various physiological roles being proposed in mammals. For example, GLP‐1 functions as an anorexigenic neurotransmitter in the brain and as a postprandial satiety hormone in the peripheral circulation. There is evidence that OXM and GLP‐2 also induce anorexia in mammals. Therefore, it is possible that the brain‐gut peptides OXM, GLP‐1 and GLP‐2 play physiological roles in the regulation of food intake in chickens. More recently, a novel GLP and its specific receptor were identified in the chicken brain. This review summarizes current knowledge about the role of glucagon‐related peptides in the regulation of food intake in chickens.  相似文献   

5.
Various lines of evidence suggest that appetite‐related neuropeptides in the hypothalamus are regulated by adiposity signals such as leptin and insulin in mammals. In the present study, we examined age‐dependent changes in the weight of abdominal fat and hypothalamic mRNA levels of neuropeptide Y (NPY, an orexigenic neuropeptide) and proopiomelanocortin (POMC, a precursor of anorexigenic neuropeptides) in growing chickens at 7, 14, 21 and 28 days of age. Hypothalamic NPY mRNA levels were significantly (P < 0.05) decreased after 14 days of age, whereas hypothalamic POMC mRNA levels were significantly (P < 0.05) increased at 28 days of age. The percentage of abdominal fat was significantly increased after 14 days of age in chickens. We next examined the correlation of hypothalamic NPY and POMC mRNA levels and several parameters at 28 days of age. There were no significant correlations between hypothalamic mRNA levels of NPY or POMC and the percentage of abdominal fat. These findings suggest that the gene expressions of NPY and POMC do not depend on adiposity in chickens, at least in 28‐day‐old layer chickens.  相似文献   

6.
Impressions and purchasing intentions of Japanese consumers regarding pork produced by ‘Ecofeed’, a trademark of food‐waste or co‐product animal feeds certified by the Japanese government, were investigated by a questionnaire on the Internet. ‘Ecofeed’ did not elicit specific impressions as compared to domestic, imported, Kurobuta (in Japan), and specific pathogen‐free (SPF) pork. Purchasing intent for ‘Ecofeed’ pork was the second lowest of the five pork products. Knowledge and purchasing experience regarding ‘Ecofeed’ pork was the lowest of the five pork products. Respondents were classified into four categories according to their impressions of ‘Ecofeed’ pork. The largest category of respondents did not have any specific impression of ‘Ecofeed’ pork and had little knowledge of pork farming. A category that had a positive impression for ‘Ecofeed’ pork had high knowledge of the pork farming system. In order to establish ‘Ecofeed’ pork in Japan, our results suggest that information disclosure and education about ‘Ecofeed’, its certification system, environmental benefits and the current self‐efficiency ratio of animal feed, are needed.  相似文献   

7.
The present study was conducted to verify how feed restriction affects gut microbiota and gene hepatic expression in broiler chickens and how these variables are related to body weight gain. For the experiment, 21‐d‐old Cobb500TM birds were distributed in a completely randomized experimental design with three treatments: T1. Control (ad libitum—3.176 Mcal/kg ME—metabolizable energy—and 19% CP—crude protein); T2. Energetic restriction (2.224 Mcal/kg ME and 19% CP) from 22 to 42 days with consumption equivalent to control; T3. Quantitative restriction (70% restriction, i.e., restricted broilers ingested only 30% of the quantity consumed by the control group—3.176 Mcal/kg ME and 19% CP) for 7 days, followed by refeeding ad libitum from 28 to 42 days. Ileum and caecum microbiota collections were made at 21, 28 and 42 days of age. Hepatic tissue was collected at 28 and 42 days old for relative gene expression analyses. At 43‐d‐old, body composition was quantified by DXA (Dual‐energy X‐ray Absorptiometry). Both feed restriction programmes decreased Lactobacillus and increased Enterococcus and Enterobacteriaceae counts. No differences were found in the refeeding period. Energetic restriction induced the expression of CPT1‐A (Carnitine palmitoyltransferase 1A) gene, and decreased body fat mass. Quantitative feed restriction increased lipogenic and decreased lipolytic gene expression. In the refeeding period, CPT1‐A gene expression was induced, without changing the broilers body composition. Positive associations were found between BWG (Body Weight Gain) and Lactobacillus and Clostridium cluster IV groups, and negatively associations with Enterobacteriaceae and Enterococcus bacterial groups. In conclusion, differences found in microbiota were similar between the two feed restriction programmes, however, hepatic gene expression differences were only found in quantitative restriction. Higher counts of Lactobacillus and Clostridium cluster IV groups in ileum are likely to be related to better broiler performance and low expression of lipogenic genes.  相似文献   

8.
We investigated the effects of beta‐glucans (Saccharomyces cerevisiae) ingestion on metabolic parameters of Wistar rats receiving high‐fat diet. The experimental period was divided into two stages: in the first one, the animals were divided into two groups containing 12 animals each. The first group received commercial feed and the second received high‐fat diet containing 20% of pork fat during 60 days. At the end of this period, body weight, blood glucose and Lee index were assessed. In the second stage, those 24 animals were redivided into four groups: (C) – control diet; (CB) – control diet and treated with Beta‐glucan (BG); (O) – obese animals and (OB) – obese animals treated with BG. Animals from groups CB and OB received 30 mg/kg of BG dissolved in saline solution by gavage. Animals from groups C and O received only saline solution for 28 days. The design used was totally randomized in 2 × 2 factorial scheme. Data were submitted to analysis of variance (anova ). Animals from OB group showed inferior levels (p < 0.05) of total cholesterol (13.33%), triacylglycerols (16.77%) and blood glucose (23.97%) when compared to the animals from group O. The use of BG has provided smaller increase in Lee index (p < 0.05), without promoting alteration in feed and water consumption, organs weight, HDL‐C, LDL+VLDL‐C, carcass composition, villus/crypt ratio, and pancreas, kidney and stomach histology. BG from S. cerevisiae promoted beneficial metabolic effects in rats receiving high‐fat diet.  相似文献   

9.
Four wethers were used in a 4 × 4 Latin square design experiment to evaluate in vivo digestibility of total mixed ration (TMR) silage with food by‐products for dairy cows, and the ruminal condition and nitrogen (N) balance were examined. Five by‐products (i.e. potato waste, noodle waste, soybean curd residue, soy sauce cake and green tea waste) were obtained. Four types of TMR silage were used: control (C) containing roughage and commercial concentrate, T1:20% and T1:40% containing the five by‐products replacing 20% and 40% of the commercial concentrate on a dry matter (DM) basis, respectively, and T2:40% containing three by‐products (potato waste, noodle waste and soybean curd residue) replacing 40% of the commercial concentrate on a DM basis. The ingredients were mixed and preserved in oil drum silos for 4 months. The TMR silages showed 4.02–4.44% and 1.75–2.19% for pH and lactic acid contents, respectively. The digestibility of DM and neutral detergent fiber, and total digestible nutrient content were higher (P < 0.05) for T2:40% feeding than for C feeding. Urinary nitrogen excretion tended to be lower (P = 0.07) for T2:40% than for C. The results suggested 40% replacing of commercial concentrate by using the three food by‐products can be most suitable for TMR silage.  相似文献   

10.
Due to its decisive function in the avian metabolic, endocrine and immune system L‐arginine (Arg) is dietary indispensable for chickens. In 12‐week‐old cockerels of two high‐ and two low‐performing purebred layer lines, the effects of increasing dietary Arg on the haematological and febrile response were studied over 48 h after single lipopolysaccharide (LPS) injection. The offered diets contained Arg equivalent to 70%, 100% and 200% of recommended supply. Pathophysiological alterations in weight gain, feed intake, body temperature and differential blood count were examined in comparison with their physiological initial values. Within the first 24 h after LPS injection, cockerels reduced feed intake and lost body weight subsequently. Thereby, low‐performing genotypes lost body weight to a lesser extent than high‐performing ones. The loss of body weight was further intensified by deficient dietary Arg. Within the following 24 h, cockerels recovered by improving feed intake and weight gain. Furthermore, LPS induced genotype‐specific fever response: both brown genotypes showed initial hypothermia followed by longer lasting moderate hyperthermia, whereas the white genotypes exhibited biphasic hyperthermia. Fever response was accompanied by significant changes in differential blood counts. Characterized by lymphopenia and heterophilia, a severe leucopenia was observed from 4 to 8 h after LPS injection and replaced by a marked leucocytosis with longer lasting monocytosis up to 48 h after LPS injection. Under given pathophysiological conditions, deficiently Arg‐supplied cockerels showed higher total leucocyte counts than adequately and excessively Arg‐supplied cockerels. However, deficient and surplus dietary Arg tended to cause higher ratios between heterophils and lymphocytes. To conclude, present results confirmed that LPS induced numerous immunological changes in 12‐week‐old cockerels and emphasized that chicken's genotype is a source of variation to be considered for immunological studies. Deficient dietary Arg intensified acute changes in differential blood counts and weight gain during LPS‐induced inflammation.  相似文献   

11.
The objective of this meta‐analysis was to summarize available information on the prevalence of thermotolerant Campylobacter (TC) in different food‐producing animals worldwide. Databases (i.e., PubMed, ScienceDirect, Scopus) were searched from 1980 to 2017 unrestricted by language. The inclusion criteria were as follows: prevalence or incidence studies, published in peer‐reviewed journals, and they must have reported the total number of animal samples studied and the number of samples that were positive for the presence of TC. When the identification of Campylobacter species was available, this information was included in the analysis. Multilevel random‐effect meta‐analysis models were fitted to estimate mean occurrence rate of TC and to compare them among different factors potentially associated with the outcome. The mean occurrence rate of TC in food‐producing animals was 0.424 (95% CI: 0.394–0.455), and the mean occurrence rate of Campylobacter jejuni and Campylobacter coli were 0.214 and 0.133, respectively. Pigs and poultry showed the highest prevalence of TC; however, there were differences in the prevalence of each Campylobacter species. Campylobacter jejuni was observed in broilers (0.322; 95% CI: 0.273–0.377) and hens (0.395; 95% CI: 0.265–0.542), while C. coli was restricted essentially in pigs (0.553; 95% CI: 0.541–0.650). The prevalence of C. jejuni in intensively bred cattle was higher (0.302; 95% CI: 0.227–0.389) than the prevalence in extensively bred cattle (0.172; 95% CI: 0.119–0.242) while the prevalence of C. coli was similar (0.051; 95% CI: 0.028–0.091 vs. 0.050; 95% CI: 0.027–0.091) in both production systems. Agar with or without blood used for the isolation of TC did not affect the prevalence observed. The method of species identification did not seem to generate differences in the prevalence of Campylobacter species. The prevalence of Campylobacter in primary food production has a strong impact on the entire agri‐food chain. National authorities must monitor the situation with the aim to establish the appropriate risk management measures.  相似文献   

12.
In this study, effects of grazing‐experienced heifer presence on foraging behavior development at the feeding station (FS) scale for first‐grazing season calves were determined. A group of four calves grazing alone (C), and another comprising four calves (Wc) and three grazing‐experienced heifers (Wh), were alternately stocked every day for 2 h on the same pasture for 26 days. The foraging time budget for Wc was significantly longer than that for C (P < 0.05) on day 7, and was similar to that for Wh on all days. Bite rate per FS was significantly higher for Wc (15.5 bite/min) than for C (13.2 bite/min) from day 1 to 14 (33.4 vs. 29.0 bite/min, respectively; P < 0.01) and significantly lower than that for Wh on all days. The number of steps taken between adjacent FSs by Wc (4.7) was significantly lower than that for C (7.2) on days 1 and 14 (2.1 vs. 2.9 steps, respectively; P < 0.01) and was similar to Wh on all days. This suggests that grazing‐experienced heifers have positive effects on the foraging behavior development of new‐season grazing calves through 14 days after the start of stocking.  相似文献   

13.
14.
Towards the continuous improvement of its inspection system, the Canadian Food Inspection Agency (CFIA) is developing an Establishment‐based Risk Assessment model for Hatcheries to allocate inspection resources based on the food safety risk associated with the Canadian hatcheries falling under its jurisdiction. The objectives of the current study were to identify and select critical food safety‐related risk factors that would be included in this model, with a main focus on Salmonella. A literature review was used to develop a comprehensive list of risk factors that could potentially contribute to the food safety risk attributed to Canadian hatcheries operating in all production streams (breeders, layers, broilers, turkeys, waterfowl and game birds). The development of this list used a selection process that was conducted according to the availability of data sources, the clarity of definition and the measurability of the selected risk factors. A panel of experts reviewed and adjusted the identified risk factors. A final list of 29 risk factors was generated; 20 originated from the scientific literature and nine from the expert panel. Risk factors were grouped in three clusters according to whether they pertained to the inherent risk (nine factors identified), risk mitigation (nine factors identified) or compliance of a hatchery with its preventive control plan and regulatory requirements (11 factors identified). Criteria for assessing each risk factor were defined based on common practices used in the Canadian hatchery industry. This comprehensive list of risk factors and criteria represents useful information to support the design and implementation of a Canadian risk assessment model for hatcheries, but could also be used by like‐minded food safety authorities.  相似文献   

15.
试验测定了常温和低温下限饲肉鸡和非限饲肉鸡体内一氧化氮(NO)含量、红细胞比容(PCV)和心脏指数的变化,以探讨早期限饲降低肉鸡肺动脉高压综合征(PHS)发病率的机理。试验结果显示低温下肉鸡的PCV值、心脏指数和PHS的发病率显著升高,NO水平在低温早期显著降低,然而随着低温时间的延长,低温处理组肉鸡的血浆NO水平反而代偿性升高。早期限饲显著降低了肉鸡生长早期的红细胞压积值,并显著降低了42日龄心脏指数和PHS的发病率。限饲鸡在限饲期间血浆NO水平显著降低,但其他阶段与非限饲鸡差异不显著。这提示早期限饲能够缓解肉鸡肺动脉高压和右心肥大的产生,其机理可能与NO和PCV改变所致的血流动力学变化有关。  相似文献   

16.
The objective of this study was to evaluate the effect of substituting brown rice grain for corn grain in total mixed ration (TMR) silage containing food by‐products on the milk production, whole‐tract nutrient digestibility and nitrogen balance in dairy cows. Six multiparous Holstein cows were used in a crossover design with two dietary treatments: a diet containing 30.9% steam‐flaked corn (corn TMR) or 30.9% steam‐flaked brown rice (rice TMR) with wet soybean curd residue and wet soy sauce cake. Dietary treatment did not affect the dry matter intake, milk yield and compositions in dairy cows. The dry matter and starch digestibility were higher, and the neutral detergent fiber digestibility was lower for rice TMR than for corn TMR. The urinary nitrogen (N) excretion as a proportion of the N intake was lower for rice TMR than for corn TMR with no dietary effect on N secretion in milk and fecal N excretion. These results indicated that the replacement of corn with brown rice in TMR silage relatively reduced urinary N loss without adverse effects on feed intake and milk production, when food by‐products such as soybean curd residue were included in the TMR silage as dietary crude protein sources.  相似文献   

17.
Four wethers were used in a 4 × 4 Latin square design experiment to evaluate the applicability of two types of total mixed ration (TMR) silage with food by‐products. Four food by‐products (i.e., potato waste, soy sauce cake, soybean curd residue and noodle waste) were obtained and mixed with commercial concentrate (CC) as TMR silage. The two types of TMR silage, T1 and T2, each contained CC, in addition to all by‐products for T1 (TRE1), and soy sauce cake and noodle waste for T2 (TRE2) on a dry matter (DM) basis. The silage was well‐fermented with low pH values and high lactic acid concentration. As the experimental treatments, T1, T2 and CC (CTL) were fed with a basal diet. The result showed that the digestibility of DM and organic matter (OM) were higher for T1 than for CC (P < 0.05), while crude protein digestibility was not significantly different among T1, T2 and CC. The retained nitrogen was not affected by inclusion of food by‐products. Ruminal pH in TRE1 and TRE2 immediately decreased compared to that in CTL. The study suggested that the two types of TMR silage, including food by‐products, might be used as a substitute for commercial concentrate.  相似文献   

18.
本研究旨在评估母羊妊娠后期限饲对其肝脏功能及抗氧化性能的影响。试验选择平均体重为(52.82±2.72)kg的妊娠后期母羊(2~3胎次)36只,随机分为3组,每组6个重复,每个重复2头羊。各组分别饲喂对照组日粮(代谢能:0.68 MJ/kg代谢体重/d)、处理1组日粮(代谢能:0.17 MJ/kg代谢体重/d)、处理2组日粮(代谢能:0.34 MJ/kg代谢体重/d),试验从妊娠90 d持续至140 d。结果:处理1组母羊肝脏脂肪含量较对照组和处理2组显著提高了288.03%和282.48%(P<0.05)。与对照组相比,处理1组肝脏水分、灰分和蛋白质占比显著降低19.28%、44.32%和45.83%(P<0.05),但处理1组肝脏脂肪占比较对照组显著提高210.19%(P<0.05)。处理1组和处理2组血清非酯化脂肪酸含量较对照组分别提高199.94%和185.51%(P<0.05)。与对照组相比,处理1组血清β-羟丁酸和肝脏甘油三酯含量显著提高392.45%和329.55%(P<0.05)。处理1组肝脏超氧化物歧化酶、过氧化氢酶和总抗氧化力活性较对照组显著提高103.32%、83.36%和75.85%(P<0.05),同时处理1组丙二醛含量较对照组和处理2组显著提高54.52%和67.31%(P<0.05)。结论:妊娠后期限制母羊采食量会导致肝脏重量和蛋白质含量下降,同时引起肝脏脂肪的积累,肝脏抗氧化功能失衡。  相似文献   

19.
The effects of the 5‐HT1A receptor agonist 8‐OH‐DPAT on food and water intake in male broiler chickens were investigated. The injection of 25 or 50 μg/kg of 8‐OH‐DPAT 15 min before refeeding in fasted animals produced a decrease in food intake. No effect was observed in drinking. The injection of 25 or 50 μg/kg of the 8‐OH‐DPAT 60 min after the start of refeeding did not produce any significant modification in food intake. No effect on drinking was recorded. The agonist 8‐OH‐DPAT injected 15 min before water presentation in water‐deprived chickens, produced an increased drinking 60 min after the presentation of water. No effect on food intake was observed. The results show that the effect on food intake of the agonist 8‐OH‐DPAT in fasted–refed broiler chickens was similar to those observed in mammals and layer‐strain chickens. However, the agonist did not alter significantly the food intake when the broilers were fed 60 min before the injection. These results are contrary to the observed effects in mammals and in layer‐strain chickens. Probably, the selection for rapid growth rate in broilers causes modifications in the feeding control pattern. The comparison between broilers and layers strain may be a useful tool to elucidate the complex mechanisms involved in food and water intake regulation in chickens.  相似文献   

20.
This study investigated the effects of intrauterine growth restriction during late pregnancy on the ovine fetal renal function and renal antioxidant capacity. Eighteen ewes pregnant were randomly divided into control group (CG, ad libitum, 0.67 MJ ME·BW−0.75·day−1, n = 6), restricted group 1 (RG1, 0.18 MJ ME·BW−0.75·day−1, n = 6), and restricted group 2 (RG2, 0.33 MJ ME·BW−0.75·day−1, n = 6). At 140 days, the fetal blood, allantoic fluid and kidney tissue were collected to determinate fetal renal function and renal antioxidant capacity. The results showed that the fetal weight, kidney weight, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), aquaporin-2 (AQP-2) and aquaporin-3 (AQP-3), and total antioxidant capacity (T-AOC) in RG1 group were decreased compared with the CG (P < 0.05), but the contents of β2-Microglobulin (β 2-MG), cystatin C (Cys-C), filtered sodium excretion fraction (FENa), malondialdehyde (MDA), and hydroxyl radical (OH) in RG1 group were increased (P < 0.05). The impaired ovine fetal renal growth, antioxidant imbalance and dysfunction of glomerulus ultrafiltration, and the renal tubules reabsorption were induced by maternal malnutrition during late pregnancy.  相似文献   

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