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81.
82.
A trial using 64 weanling pigs (TR4×PIC C22) was conducted to determine the effects of menhaden fish oil supplementation and diet complexity on performance and immune response of nursery pigs. Pigs (17 days and 6.27±1.16 kg) were weaned into a segregated early wean facility and given free access to a complex diet for 7 days post-weaning. At day 0 (day 7 post-weaning), pigs were blocked by weight and allotted to 64 pens. Treatments (Trt) were arranged as a 2×2×2 factorial arrangement. Main effects included diet (complex versus simple), oil (menhaden fish (MFO) versus corn (CO)), and immunogen (saline versus lipopolysaccharide (LPS)). Experimental diets contained 6% oil (6% CO or 5% MFO+1% CO) and were fed for 14 days. On day 12, i.v. injections of either LPS (150 μg/kg) or saline were given, followed by blood collection at 30 min intervals for 6 h. After the immune challenge (day 14), pigs were placed onto a common corn-soybean meal fortified diet and growth performance was evaluated until termination of the study (day 28). Pigs were weighed and feed intakes recorded at 7, 14, and 28 days. Prior to immune challenge (day 12), there were differences in BW for pigs fed complex versus simple diets (P<0.01; 13.1 and 12.1 kg, respectively) and pigs fed CO versus MFO diets (P<0.05; 12.9 and 12.3 kg, respectively). During the challenge period, for pigs treated with LPS there was a Time×Immunogen×Oil effect (P<0.001) for serum cortisol with MFO fed pigs having lower serum cortisol as compared to CO fed pigs. Also, during the challenge period, for pigs treated with LPS there was a Time×Diet×Immunogen×Oil effect (P<0.001) for serum tumor necrosis factor- (TNF-) with pigs fed complex diets supplemented with CO having higher serum TNF- as compared with pigs fed complex diets supplemented with MFO. At days 14 and 28, LPS-treated pigs had lower BW than saline injected controls (P<0.001 and 0.01, respectively). In addition, pigs fed simplified diets continued to have lower BW after challenge compared to pigs fed a complex diet. Interestingly, there were no differences (P>0.10) in BW after challenge in pigs fed MFO. This study suggests that MFO supplementation alters the immune response during LPS challenge and that simplified diets may compromise nursery performance.  相似文献   
83.
抗病毒精液稀释液在养猪企业实际应用效果表明,抗病毒精液稀释液可使公猪精液在体外恒温有效保存时间延长至6d,精子平均活力达0.7,授配母猪情期受胎率达86%,窝产仔数平均11.2头,仔猪产后死亡率减少13%,猪群健康率平均提高32%.抗病毒精液稀释液与养猪企业原用普通稀释液比较,养猪综合效益提高15%.抗病毒精液稀释液在猪人工授精中应用取得良好效果.  相似文献   
84.
氧化鱼油对鲤鱼生产性能和肌肉组织结构的影响   总被引:19,自引:4,他引:19  
将新鲜鱼油(过氧化物值 ,POV ,1.28meqO2/kg)和POV分别为59.28、118.79、159.85、189.37、331.82和367.86meqO2/kg 的6个氧化程度不同的鱼油按3 %加入半纯化饲料中 ,投喂60g左右二龄鲤鱼鱼种9周。结果表明 :氧化鱼油损害鲤鱼生产性能 ,即降低鲤鱼增重率(P<0.05)、增加饲料系数(P<0.05) ;氧化鱼油导致肝体比(HSI)、肾体比(KSI)和脾体比(SSI)增加 ,以POV为59.28meqO2/kg 的低氧化程度鱼油增加幅度最高 ,超过此氧化程度 ,增加态势相对减弱 ,这预示低量氧化产物刺激肝胰脏、肾脏和脾脏增生 ,高量氧化产物破坏性增强 ,抑制增生作用 ;氧化鱼油破坏肌肉组织 ,使肌纤维间隙急剧扩大、肌原纤维降解、肌原纤维模式紊乱。  相似文献   
85.
采用微波萃取的方式提取莪术中的挥发油,并通过气相色谱一质谱联用技术对其化学成分进行了分析。实验结果显示,用微波萃取莪术挥发油的得率为3.36%,高于水蒸汽蒸馏法;挥发油中莪术呋喃烯酮含量最高,达到20.14%,其次是莪术醇,为18.34%。该实验可为莪术药材及其挥发油的有效利用提供依据。  相似文献   
86.
《动物营养(英文)》2021,7(4):1360-1370
Alternative sources of fish oil (FO) are one of the major problems in aquaculture; therefore, the goal of the present study was to examine insect (black soldier fly larvae) oil (BSLO) as a potential replacer of fish/soy oil in juvenile rainbow trout (initial average weight of 32 ± 0.15 g) feed. Four diets were formulated wherein FO (control diet) was completely replaced with either soybean oil (SO) or BSLO, and an additional BSLO-based diet supplemented with 1.5% bile acid (BSLO + BA) were fed to the fish for 10 weeks. Growth performance of the BSLO fed group was similar (P > 0.05) to that of the FO and SO fed groups, however, the fish fed BSLO + BA diet registered the lowest growth (P < 0.05). Oil sources did not (P > 0.05) affect the major nutrient content of whole-body, however, the fatty acid composition of the muscle and liver was influenced (P < 0.05), with the highest 14:0, 16:0, and total saturated fatty acid detected in BSLO or BSLO + BA fed trout compared to the others (P < 0.001). No significant differences were observed in eicosapentaenoic acid + docosahexaenoic acid (EPA + DHA) or total n-3 polyunsaturated fatty acid (PUFA) content in muscle among the groups, whereas, the highest EPA:DHA and n-3:n-6 ratios were detected in the FO group. Gene expression for fatty acid binding protein (fabp), fatty acid synthase (fas), and Δ5 desaturase in the liver was lower in FO (P < 0.05), while BSLO + BA registered the highest Δ6 expression (P = 0.006). Supplementation of BA in the BSLO diet increased superoxide dismutase (SOD) and catalase (CAT) activities compared to the other groups (P < 0.05). In conclusion, BSLO could serve as a substitute for FO and SO in rainbow trout diet without negatively impacting growth performance, whole-body composition and nutrient retention, and modulate the expression of fatty acid metabolism-related genes in rainbow trout.  相似文献   
87.
为了探究chi-miR-107-3p和菱形家族蛋白2(rhomboid family member 2,RHBDF2)基因在不同品种(系)和光控增绒绒山羊兴盛前期(5~7月份)皮肤毛囊重建时的表达差异,本试验在7月份采集内蒙古阿拉善型绒山羊、敏盖绒山羊和光控增绒技术处理的阿尔巴斯型绒山羊体侧皮肤毛囊组织,采用组织切片技术对组织形态比较分析,实时荧光定量PCR法检测chi-miR-107-3p和RHBDF2基因的表达量。结果显示,在皮肤毛囊兴盛前期,阿拉善型绒山羊次级毛囊正处于重建阶段,敏盖绒山羊和阿尔巴斯型绒山羊(光控增绒)次级毛囊重建已基本完成;在阿拉善型绒山羊皮肤组织中chi-miR-107-3p表达量极显著高于敏盖绒山羊和阿尔巴斯型绒山羊(光控增绒)(P<0.01),而RHBDF2基因表达量极显著低于其他两品种(系)(P<0.01),且RHBDF2基因表达量在敏盖绒山羊皮肤组织中显著低于阿尔巴斯型绒山羊(P<0.05)。不同品种(系)和光控增绒绒山羊皮肤毛囊兴盛前期组织显微结构与chi-miR-107-3p、RHBDF2基因在皮肤组织中的表达差异分析结果相一致,次级毛囊重建初期chi-miR-107-3p表达量较高,而RHBDF2基因表达量极低,随着次级毛囊重建完成,chi-miR-107-3p表达量明显降低,RHBDF2基因表达量逐渐增高,且在不同品种(系)内蒙古绒山羊绒毛生长发育过程中的表达机制基本相同。因此,chi-miR-107-3p和RHBDF2基因是绒山羊皮肤毛囊生长发育的重要调控因子。  相似文献   
88.
Recent technological advances in the human food industry with respect to meat processing have decreased the availability of animal proteins to the pet food industry which typically formulates diets with an excess of animal protein. In the long term, this is not sustainable; thus, alternative protein sources need to be investigated. This study examined three canine diets, comparing a typical animal protein‐based diet (control) with two experimental diets where the animal protein was substituted in part with vegetable protein (formulated based either on total protein or amino acid content) using a broiler model. Each diet was fed to six cages each containing two birds from day 15, 18 cages in total (36 birds). Excreta were collected from days 19 to 21. On day 23, birds were euthanized and weighed, and their ileal digesta were collected and pooled for each cage. In addition, one leg per cage was collected for evaluation of muscle mass. Results showed no significant difference in animal performance (feed intake or live weight gain) or muscle to leg proportion across the diets. Birds fed the control diet and the diet balanced for amino acid content exhibited the greatest coefficients of apparent metabolizability for nitrogen (p < .001). Birds fed the diets that contained partial replacement of animal with vegetable protein generally had greater ileal digestibility of amino acids compared to birds fed the control (animal protein) diet. Analysis of excreta showed no dietary difference in terms of dry matter content; however, birds fed the diet balanced for total protein and the diet balanced for amino acid content had significantly greater excreta nitrogen than the control (= .038). Overall, the study suggests vegetable proteins when formulated based on amino acid content are a viable alternative to animal proteins in canine diets.  相似文献   
89.
1. Studies were conducted with tall oil fatty acids (TOFA) to determine their effect on broiler chicken performance and ileal microbiota. TOFA, a product originating from coniferous trees and recovered by fractional distillation of side-streams from pulp production, mainly comprises free long-chain fatty acids (~90%) and resin acids (~8%). Conjugated linolenic acids and pinolenic acid are characteristic fatty acid components of TOFA.

2. TOFA products at 750 mg/kg feed were tested in two 35-day broiler chicken trials, each using a wheat soya-based diet and with 12 replicate pens per treatment. In both trials, TOFA improved body weight gain at all time points (P < 0.001) and feed conversion efficiency during the first 21 days (P < 0.01). Two different dry TOFA formulations (silica carrier and palm oil coating) were tested and showed performance effects similar to liquid TOFA.

3. Ileal digesta of the broiler chickens was analysed for total eubacteria, Lactobacillus spp., Enterococcus spp., Escherichia coli and Clostridium perfringens on days 14 and 35. TOFA significantly increased total eubacteria and lactobacilli density on day 14 (P < 0.05). There was a significant positive correlation between these bacterial groups and broiler body weight on day 14 (P < 0.01).

4. A numerical reduction in C. perfringens was observed. In vitro growth inhibition studies showed that C. perfringens was strongly inhibited by 10 mg/l TOFA (P < 0.001), while common lactobacilli were resistant to >250 mg/l. The in vitro results were thus in line with in vivo observations.

5. The mechanisms behind the bacterial shifts and their role in performance improvement are unknown. Further purification of TOFA components is needed to identify the effective agents.  相似文献   

90.
植物源蒸馏油是一种新型植物油,本文探讨了植物源蒸馏油在害虫控制中的应用潜力。以矿物油乳剂为参照,以柑橘木虱为试虫,分析比较植物油蒸馏油的触杀和拒避作用。植物油和矿物油对柑橘木虱的卵、若虫和成虫均有一定的触杀作用,其中对若虫尤其低龄若虫的触杀作用最强,可达90%以上。两种油剂对雌虫产卵均有一定的拒避作用,拒避雌虫产卵维持约2 d。两种油剂对成虫寄主选择没有明显的拒避作用。总体上,植物源蒸馏油对柑橘木虱的触杀作用以及对成虫的拒避作用与矿物油相当。如果进一步改进该植物油的乳化效果,可替代矿物油乳剂应用于害虫防治中。  相似文献   
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