BIOCHEMICAL CHANGES DURING DEVELOPMENT OF EGGS AND YOLK-SAC LARVAE OF HERRING AND PLAICE

Changes in quantities of water, sodium, potassium, lipid and protein were compared in developing eggs and yolk-sac larvae of herring dupes harengus L., a species with demersal eggs, and plaice Pleuroncctcs platessa L., a species with pelagic eggs. The principal difference between the two species was the occurrence in herring, but not in plaice of considerable increases in water content and in one or both of the above ions at three distinct stages: at fertilization,during the middle stage of egg development, and in the days immediately after hatching. Newly hatched larvae of the two species differed greatly in water content because of the difference in mass and water content of the yolk, not in the water content of the rest of the body. In herring, there were increases in sodium and potassium which coincided broadly with the increase in water content. These differences are related to the gradual acquisition of buoyancy by herring during this period, comparable with the buoyancy conferred on plaice eggs

Effects of florfenicol exposure on growth,development and antioxidant capacity of flounder Paralichthys olivaceus larvae at different developmental stages

Antibiotics are widespread in various environmental media,and may pose a potential threat to aquatic ecosystems and non-target aquatic organisms.Florfenicol(FLO)is one of the most commonly used antibiotics in aquaculture,and extensively used to substitute chloramphenicol with its strong sterilization and low adverse ef fect.In this study,flounder Paralichthys olivaceus,an important economic fish species in seawater was used as an experimental subject.Five exposure concentrations of FLO(including environmentrelated concentrations)were set at 0,0.01,0.1,1,and 10 mg/L.Ef fects of FLO exposure for 168 h on growth and development,motor behavior,antioxidant enzyme activity,malondialdehyde(MDA)content,and thyroid hormone level of P.olivaceus larvae were studied in pre-larvae(1 dpf)and post-larvae(20 dpf).The results show that the short-term FLO exposure could promote the larvae growth to some degrees,but inhibit them as the exposure time prolonged.For pre-larvae,FLO at 0.01 mg/L could stimulate the motor nerve system and increase the swimming ability,but inhibited it at 1 mg/L.With the increasing dosage of FLO,the superoxide dismutase(SOD)and MDA contents were elevated,reaching the maximum in the 1 mg/L FLO group.The pre-larvae were more sensitive than the post-larvae to FLO in the environment,and the growth and immune resistance could be damaged with long exposure.Post-larvae were more tolerant to external pollutants,FLO at 1 mg/L could promote the motor behavior and reduce SOD and MDA contents.Therefore,FLO can be used as an antibiotic at a proper concentration but as a drug to prevent disease in a long-term way.

Advances in Studies of the Effects of Starvation on Growth and Development of Fish Larvae

Starvation has important effects on early development of fish. It determines the survival and growth of fish larvae,and plays an important role in the dynamics of fish population and fisheries recruitment. In this review,we discuss the current studies about the effects of starvation on growth and development of fish larval stage. The goals of this review are to understand some adaptive mechanisms and ecological countermeasures of starved fish larvae and to provide the scientific guideline for exploring early life history processes,evaluating the nutrition condition and growth of larval fish,protecting fish resource and breeding fish larvae.

Expression and function of WNT4 involved in larvae development and limb regeneration in Portunus trituberculatus

The wingless-related integration site(WNT)proteins are a family of secreted glycoproteins that are evolutionarily conserved and are believed to be involved in evolution in vertebrates and invertebrates.WNT signaling pathways may be associated with limb regeneration and development in crustaceans.However,the detail mechanisms remain unclear.Therefore,the distribution of WNT4 in the hepatopancreas,muscle,hemocyte,ganglion,heart,eyestalk,gill tissue,and diff erent larvae development stages of the swimming crab(Portunus trituberculatus)were characterized using immunofl uorescence,real-time PCR,and Western blotting.Signifi cant PtWNT4 expression was detected in heart and eyestalk.In addition,PtWNT4 was expressed in all larval stages of P.trituberculatus with a dynamic expression pattern,especially in the eyestalk and other organs in the carapace area.The injection of WNT4 dsRNA into regenerative limbs signifi cantly decreased PtWNT4 mRNA levels in the eyestalk,heart,and muscle,resulting in 1.9-fold,2.2-fold,and 2.7-fold decreases compared with those detected in the group injected with crab saline(P<0.05),respectively,indicating successful gene silencing.Overall,expression analysis on the WNT4 using RNAi provides an insight to its functional mechanism during limb regeneration in P.trituberculatus.The results not only demonstrated the requirement for WNT4 in limb regeneration of Crustaceans,but also suggested its ability to promote larval development at specifi c stages.

Effects of Exogenous Carbon Monoxide Releasing Molecules on the Development of Zebrafish Embryos and Larvae

The use of exogenous carbon monoxide releasing molecules（CORMs）provides promise for clinical application;however,the hazard potential of CORMs in vivo remains poorly understood.The developmental toxicity of CORM-3 was investigated by exposure to concentrations ranging from 6.25 to400μmol/L during 4-144 h post fertilization.Toxicity endpoints of mortality,spontaneous movement,heart rate,hatching rate,malformation,body length,and larval behavior were measured.

Growth and Development of Larvae and Juveniles of Carassius auratus gibelio

The growth and development of larvae and juveniles was morphologically investigated in Carassius auratus gibelio. The results showed that it took 52 h from fertilization to hatching at 22 - 25℃. The newly hatched larvae had transparent body, with the head fight near the yolk sac; the yolk sac accounted for 2/3 of larval volume, which was exhausted in the four-day-old larvae that started the exogenous nutrient period. The larvae were found to develop into juveniles from a few scales on the 20^th day after hatching to whole scales, fingerling, on the 28^th day after hatching. The relationship between total length（TL） and age in days（D） was described as ： TL = 0.001 2D3 - 0. 038 8/32 ＋ 1.043 2D ＋ 3. 945 8 （ r^2 = 0.998 ）. The relationship between body length （L） and body weight （W） of larvae and juveniles was expressed as： m = 1E -05L^3.3769（ r^2 = 0.982 7）. The formula between body length and body height during the development of the fish was described as ： H = 0.0（30 1L3 -0. 028 4L2 ＋ 1. 281 6L -7. 250 5 （ r^2 = 0. 988 6）. The findings provided the theoretical instruction for practical production of C. auratus gibelio.

Study on Embryonic Development, Larva,Juvenile and Young Fish of Epinephelus fuscoguttatus

This study aimed to study the development characteristics of Epinephelus fuscoguttatus at the embryo, larval, juvenile and young fish stages, thereby improving the breeding efficiency of E. fuscoguttatus. [Method] The morphological characteristics and embryonic and post embryonic development of E. fuscoguttatus, including the occurrence and development of nervous system, digestive system and circulatory system, were observed and analyzed using eggs self-fertilized with artificially induced spawning in the breeding base of Hainan Province. [Result] The fertilized egg of E. fuscoguttatus is spherical, colorless transparent with single oil ball, and its diameter ranges from 0.83 to 0.94 mm. Based on the development process, the embryonic development of E. fuscoguttatus was divided into six stages, namely fertilized egg stage, cleavage stage, blastula stage, gastrula stage, idiosome formation stage and hatching stage. The entire embryonic development of E. fuscoguttatus required 20 h 47 min in the sea water with temperature of 28.4-31.9℃ salinity of 31-32 and pH of 8.4, and the total cumulative temperature was 455.361 ℃·h. The post embryonic development of E. fuscoguttatus was divided into larval stage, juvenile stage and young fish stage based on the features of the yolk-sac, second dorsal fin spine, pelvic fin spine, and body color. Accordingly, the larval stage was further classified into pre-larva and post-larva, with or without yolk-sac, respectively. The extension and shrinkage of the first pelvic fin spine and the second dorsal fin spine as well as the spinules on aforementioned spines were the most significant changes during the post embryonic development of E. fuscoguttatus. [Conclusion] This study will provide some basic data for industrial breeding of E. fuscoguttatus.

Embryonic and larval development in barfin flounder Verasper moseri (Jordan and Gilbert)

Broodstock of Verasper moseri （Jordan and Gilbert） aged 3-4 years old were selected, and reinforced cultivation was conducted to promote maturation under controlled water temperature and photoperiod conditions. Fertilized eggs were obtained by artificial fertilization, and the development of embryos, larvae and juveniles was observed continuously. The results showed that the fertilized eggs of V. moseri were spherical, with transparent yolk and homogeneous bioplasm, and had no oil globule inside. The average diameter of the eggs was 1.77＋0.02 mm. The eggs of V. moseri were buoyant in water with salinity above 35. The cleavage type was typical discoidal. Young pigment cells appeared when olfactory plates began to form. Hatching occurred at 187 h after fertilization at a water temperature of 8.5℃. The newly hatched larvae, floating on the water surface, were transparent with an average total length of 4.69±0.15 mm. During the cultivation period, when the water temperature was raised from 9 to 14.5℃, 4-day old larvae showed more melanophores on the body surface, making the larvae gray in color. The pectoral fins began to develop, which enabled the larvae to swim horizontally and in a lively manner. On days 7-8, the digestive duct formed. The yolk sac was small and black. The yolk sac was absorbed on day 11. Larvae took food actively, and body length and body height clearly increased. The rudiments of dorsal and anal fin pterygiophores were discernible and caudal fin ray elements formed on day 19. On day 24, the larval notochord flexed upwards, and the rays of unpaired fins began to differentiate. Pigment cells converged on the dorsal and anal fin rays, and the mastoid teeth on the mandible appeared. On day 29, the left eyes of juveniles began to move upwards. Depigmentation began in some juveniles and they became sandy brown in color on day 37. Most juveniles began to settle on the bottom of the tank. The left eyes of juveniles migrated completely to the right side on day 50, when the average body length attained 2.5±0.18 cm, and juveniles accomplished metamorphosis to young. The embryonic and larval characters of several flounder species are compared.

Ontogenetic development in the morphology and behavior of loach(Misgurnus anguillicaudatus) during early life stages

Loach （Misgurnus anguillicaudatus） is a commercially important fish in China and an ideal aquaculture species. However, culturists experience high larval and juvenile mortality during mass production. To provide insight into ways to improve larviculture techniques, we describe the morphological characteristics and behavior of loach during the larval and early juvenile stages. Yolksae larvae ranged from 2.8 to 4.0 mm body length （BL） between days 0 to 4; preflexion larvae ranged from 3.6 to 5.5 mm BL between days 4 to 6; flexion larvae ranged from 4.8 to 8.1 mm BL between days 5 and 14; and post-flexion larvae ranged from 7. l to 15.7 mm BL between days 11 to 27; the minimum length and age of juveniles was 14.1 mm BL and 23 d, respectively. Loach are demersal from hatch through to the early juvenile stages. A suite of morphological characteristics （e.g., external gill filament and ventral mouth opening） and behavioral traits have developed to adapt to demersal living. We observed positive allometric growth in eye diameter, head length, head height, and pectoral fin length during the early larval stages, reflecting the priorities in the development of the organs essential for survival. Our results provide a basis for developing techniques to improve the survival of larval and juvenile loach during mass production.

mRNA differential display on gene expression in settlement metamorphosis process of Ruditapes philippinarum larvae

The mRNA differential display (DDRT-PCR) technique was adopted to find out the genes related tosettlement metamorphosis development process of Ruditapes philippinarum larvae.In this study,we haveobtained three hundred and forty-six amplification bands in total from pediveliger larvae,veliger larvae,eye spot larvae and post-larvae.Sixty-five out of three hundred and forty-six bands are distinctly differen-tial display from band pattern,which can be put into four groups,standing for different expression char-acters.Sixteen differential display bands were cloned,sequenced and analyzed and nine different se-quences are obtained in the study.Three sequences have higher similarity to the cDNAs deposited indatabase and three are very similar to the rDNA of other species,considered as the rDNA of Ruditapesphilippinarum.The rest three sequences are found to be novel sequences after analyzed.Their accessionnumbers are AY916799,AY916798,and AY916797 respectively.We thought the novel sequences arepossibly relevant to the early embryo development of Ruditapes philippinarum larvae and can provide somefundamental understandings that are helpful for the improvement of scallop seed raising industry.

Experimental Analysis on Allometric Growth in Spualiobarbus curriculus Larvae and Juveniles in Zhaoqing Reach of the Pearl River

Ecological experiment was conducted in this paper to study the allometric growth in Squaliobarbus curriculus larvae and juveniles from Zhaoqing Reach of the Pearl River. The results showed that after first feeding, the organs associated to swimming, feeling and feeding of larvae differentiated rapidly, and exhibited allometric growth. The head length, tail length and head height exhibited positive allometric growth, while trunk length exhibited negative allometric growth before reaching the growth inflexion point 20 d after first feeding, and positive allometric growth after the inflection point. Body height exhibited positive allometric growth both before and after the growth inflexion point at 18 d after first feeding. The inflexion points of snout length, eye diameter and post-eye head length occurred 23, 19 and 16 d after first feeding. For swimming organs, the dorsal fin, pelvic fins and anal fin exhibited positive allometric growth both before and after the inflexion point at 18, 19 and 17 d after first feeding; but the tail fin exhibited positive allometric growth before the inflexion point at 14 d after first feeding, and negative allometric growth after the inflexion point. S. curriculus larvae can possess various abilities soon after first feeding to survive at early stage due to the rapid development of swimming, feeling, feeding and other organs, which has important ecological significance to adapt to the complex external environment.

Influence of salinity on the early development and biochemical dynamics of a marine fish, Inimicusjaponicus

Fertilised eggs of the devil stringer （Inimicusjaponicus） were incubated at different salinity levels （21, 25, 29, 33, and 37）, and then the hatching performances, morphological parameters, and biochemical composition （protein, lipid and carbohydrate） of the larvae were assayed to determine the influence of salinity on the early development ofl.japonicus. The tested salinity levels did not affect the times of hatching or mouth opening for yolk-sac larvae. However, the salinity significantly influenced the hatching and survival rates of open-mouthed larvae, as well as the morphology of yolk-sac larvae. The data indicated that 30.5 to 37.3 and 24.4 to 29.8 were suitable salinity ranges for the survival of embryos and larvae ofl.japonicus, respectively. Larvae incubated at a salinity level of 29 had the greatest full lengths, and decreasing yolk volume was positively correlated with the environmental salinity. With increasing salinity, the individual dry weights of newly hatched larvae or open-mouthed larvae decreased significantly. Newly hatched larvae incubated at a salinity level of 29 had the greatest metabolic substrate contents and gross energy levels, while the open- mouthed larvae＇s greatest values occurred at a salinity level of 25. Larvae incubated in the salinity range of 33 to 37 had the lowest nutritional reserves and energy values. Thus, the I.japonicus yolk-sac larvae acclimated more readily to the lower salinity level than the embryos, and higher salinity levels negatively influenced larval growth and development. In conclusion, the environmental salinity level should be maintained at 29-33 during embryogenesis and at 25-29 during early larval development for this species. Our results can be used to provide optimum aquaculture conditions for the early larval development of I.japonicus.

水处理对枸杞负泥虫卵和幼虫生长发育的影响

微生态因子(水、气、热等)常干扰害虫取食、交尾、繁殖等一系列与生长发育有关的行为。采用喷雾(水)和浸水法研究了水对枸杞负泥虫产卵、卵孵化及幼虫生长发育等习性的影响。结果表明,喷雾(水)处理通过环境中湿度和水的作用延缓了枸杞负泥虫成虫产卵始期及产卵历期,抑制了卵的孵化率;干扰了枸杞负泥虫中、大幼虫阶段发育时间及行为活动。水处理对枸杞负泥虫成虫产卵、卵孵化等生殖行为具明显的抑制作用,对幼虫正常行为活动产生了不同程度的影响。

绿鳍马面鲀胚后早期发育各阶段形态特征的研究

本文研究了绿鳍马面鲀(Thamnaconus septentrionalis)胚后早期发育各阶段可观、可量和可数性状的变化。结果显示,在水温为(23.0±1.0)℃条件下,1 d出现胸鳍;4 d卵黄囊消失,鳔基和第1背鳍鳍基清晰可见;7 d油球消失,出现腹鳍;8 d第1背鳍鳍基和腹鳍出膜;9 d披透明圆形小鳞;12 d鳔和腹两侧后匙骨清晰可见;14 d出现第2背鳍支鳍骨和臀鳍支鳍骨;16 d披锥形小鳞,上、下颌出现锥形齿;19 d分化出第2背鳍鳍条和臀鳍鳍条;20 d尾柄下侧长出尾鳍鳍条;24 d时,第2背鳍、臀鳍和尾鳍的鳍条形态发育完全;27 d鳔大量充气。可量性状变化的曲线方程R2值均>0.90,第1背鳍鳍高,4~30 d呈指数递增;视囊0~11和11~20 d为线性递增,0~11 d递增程度<11~20d,21~30d为指数递增;口裂4~13和22~30d为线性递增,13~22d为线性递减;全长、体长、体高和矢耳石直径等拐点前为线性递增,拐点后为指数递增,拐点集中在19~23 d。初孵仔鱼共27对肌节,头部6对,躯体21对;仔鱼末期,第2背鳍支鳍骨数为31~36根,臀鳍支鳍骨数为33~35根;稚鱼末期,第2背鳍和臀鳍鳍条数与支鳍骨数相对应,胸鳍鳍条数为15~18根,尾鳍鳍条数为12根;早期幼鱼45 d时,鳍条分节明显,第2背鳍鳍条2节,臀鳍鳍条3节,尾鳍鳍条为7~10节,50 d躯体4~5条黑色条带。研究较详尽地描述了绿鳍马面鲀胚后早期发育各阶段的形态特征,丰富了绿鳍马面鲀胚后早期发育基础资料,可为其苗种繁育提供指导。

意大利蜜蜂工蜂幼虫肠道发育过程中lncRNA的表达谱和调控作用

【目的】解析意大利蜜蜂Apis mellifera ligustica工蜂幼虫肠道发育过程中的长链非编码RNA(long non-coding RNA,lncRNA)差异表达谱,并揭示差异表达lncRNA(differentially expressed lncRNA,DElncRNA)在幼虫肠道发育中的调控作用。【方法】基于前期获得的意大利蜜蜂工蜂4,5和6日龄幼虫肠道转录组数据(分别为Am4,Am5和Am6),利用相关软件筛选Am4 vs Am5比较组和Am5 vs Am6比较组中的DElncRNA,分析DElncRNA和两个比较组中共同上调和下调lncRNA的顺式调控作用及竞争性内源RNA(competing endogenous RNA,ceRNA)的调控作用。通过RT-qPCR验证转录组数据的可靠性。【结果】在Am4 vs Am5比较组中筛选出214条上调和251条下调lncRNA,在Am5 vs Am6比较组中筛选出141条上调和332条下调lncRNA;两个比较组共有的上调和下调lncRNA分别为7和16条。Am4 vs Am5比较组中的DElncRNA潜在调控250个邻近基因,涉及细胞进程等28个GO条目及Wnt信号通路等58条KEGG通路;Am5 vs Am6比较组中的DElncRNA潜在调控295个邻近基因,涉及细胞部分等35个GO条目及FoxO信号通路等73条KEGG通路;上述两个比较组中共有的7个上调lncRNA潜在调控10个邻近基因,涉及1个GO条目及代谢通路、谷胱甘肽代谢和核质转运等7条KEGG通路。共有的16个下调lncRNA潜在调控27个邻近基因,涉及8个GO条目及精氨酸生物合成、谷胱甘肽代谢和代谢通路等13条KEGG通路。此外,Am4 vs Am5比较组中的49条DElncRNA可靶向16个差异表达miRNA(differentially expressed miRNA,DEmiRNA)进而靶向122条差异表达mRNA(differentially expressed mRNA,DEmRNA),可注释到代谢进程等24个GO条目和Wnt信号通路等21条KEGG通路。Am5 vs Am6比较组中的38条DElncRNA可靶向8条DEmiRNA进而靶向67条DEmRNA,可注释到催化活性等21个GO条目和FoxO信号通路等10条KEGG通路;上述两个比较组共有的1条下调lncRNA MSTRG.10589.2可靶向ame-miR-6052和miR-511-y,进而靶向29条DEmRNA。RT-qPCR结果显示随机选取的7条DElncRNA的相对表达量与测序数据一致,证实了所用转录组数据的可靠性。【结论】意大利蜜蜂工蜂幼虫肠道发育过程伴随着lncRNA的动态差异表达,DElncRNA可通过顺式作用和ceRNA网络潜在参与对幼虫肠道发育的调控,在幼虫肠道发育中潜在发挥重要的调控作用。

碳酸盐碱度对大鳞副泥鳅胚胎发育和仔鱼活力的影响

为探究大鳞副泥鳅(Paramisgurnus dabryanus)胚胎及仔鱼对碳酸盐碱度的适应性,将发育至囊胚期的胚胎分别放置于碳酸盐碱度为0、10、20、30和40 mmol·L^(-1)的水体中培养,记录胚胎的孵化率、孵化时间,统计仔鱼的畸形率、成活率、特定成长率及卵黄囊吸收率,并测定初孵仔鱼的不投饵存活系数(Survival activity index,SAI)。结果显示:1)碳酸盐碱度为10 mmol·L^(-1)时,胚胎孵化率最高,但与对照组差异不显著(P>0.05),碳酸盐碱度在10~20 mmol·L^(-1)时,孵化时间显著短于对照组(P<0.05);2)初孵仔鱼的畸形率随碳酸盐碱度的增加而逐渐升高,3日龄(Days after hatching,dah)仔鱼成活率则随碳酸盐碱度的增加逐渐降低;3)初孵仔鱼全长随碳酸盐碱度的增加先下降后上升,而3 dah仔鱼全长随碳酸盐碱度的增加先上升后下降,其特定生长率及卵黄囊吸收率均呈先升后降的趋势;4)随着碳酸盐碱度的增加,仔鱼SAI先升后降,其中10 mmol·L^(-1)组达到最大值。结果表明,碳酸盐碱度在0~10 mmol·L^(-1)范围内适宜大鳞副泥鳅的胚胎发育及仔鱼生长。

饥饿对双委夜蛾幼虫生长发育的影响

本研究旨在探究双委夜蛾Athetis dissimilis幼虫的耐饥饿能力,以期为该害虫的有效防控提供科学依据。通过设置不同日龄幼虫的饥饿和饥饿后复食实验,观察其存活力及生长发育情况。研究结果显示,双委夜蛾2日龄幼虫至12日龄幼虫经饥饿处理后最终全部死亡,并且随日龄的增加耐饥饿能力越强;双委夜蛾12日龄幼虫经饥饿处理后,平均存活时间可达11.90 d;14日龄双委夜蛾幼虫经饥饿处理后,有64.4%的幼虫个体能够进入化蛹。4日龄和8日龄幼虫在饥饿复食处理后,随饥饿时间的延长,幼虫历期显著延长、蛹重明显降低;12日龄幼虫经短时间饥饿处理后幼虫发育历期显著增长,但蛹重降低不显著。本研究结果说明双委夜蛾幼虫日龄越大,抗饥饿的能力越强,复食后可造成该虫再次猖獗。本研究结果对双委夜蛾的科学防控提供一定的理论指导。

熊本牡蛎幼体、葡萄牙牡蛎幼体和长牡蛎幼体共生菌群构成随宿主发育的演替差异分析

为了解同一育苗厂育苗的熊本牡蛎幼体、葡萄牙牡蛎幼体和长牡蛎幼体共生菌群随宿主发育的演替是否存在差异,采用16S rRNA高通量测序技术对这3种牡蛎幼体4个发育时期的共生细菌群落构成进行了比较。结果显示,在它们的4个发育时期共鉴定到3484个细菌OTUs,其中在D形幼虫、壳顶幼虫、眼点幼虫和稚贝期共有的OTU数分别占总OTU数的43.1%、24.9%、31.3%和36.8%。4个发育时期的优势菌主要隶属于变形菌门(Proteobacteria)、拟杆菌门(Bacteroidetes)和放线菌门(Actinobacteria),而其丰度在不同发育时期存在变化,特别是在细菌属水平差异显著。在4个发育时期3种牡蛎幼体共生菌群多样性有所差异,其中在眼点幼虫期的长牡蛎幼体中菌群多样性最高,而在壳顶幼虫期的熊本牡蛎幼体中菌群多样性最低。值得注意的是,3种牡蛎幼体的共生菌群结构随宿主发育呈现相似的演替变化,但在相同发育时期菌群结构差异显著。进一步对它们各发育时期的共生菌群潜在功能进行比较,发现由共生细菌参与的糖类的生物合成和代谢、脂质代谢、免疫系统等功能通路的丰度在D形幼虫期最高,而参与氨基酸代谢、细胞生长和死亡、其他次级代谢物的生物合成等功能通路的丰度在稚贝期最高但在壳顶幼虫期最低。这些结果表明熊本牡蛎幼体、葡萄牙牡蛎幼体和长牡蛎幼体4个发育时期的共生细菌群落构成存在较大差异,可能受宿主遗传的影响明显。

亮斑扁角水虻幼虫代替豆粕对北京鸭生长发育和血清生化指标的影响

选取150只1日龄的北京鸭,将其随机分为3组,分别在其常规饲料中添加0、10%和30%的干亮斑扁角水虻幼虫(BSFL),利用等氮等能的标准,根据蛋白能量差减去相应的豆粕含量配制BSFL蛋白饲料进行饲喂(依次简记为CK、T1、T2组),42 d后测定其生长性能、屠宰性状、脏器系数、肉质性状和血清生化指标的变化。结果表明:各组北京鸭的平均日增重、平均日采食量、料肉比、屠宰率、半净膛率、全净膛率、腹脂率、腿肌率、胸肌率均无显著差异。与CK相比,T1、T2组北京鸭的脾(脏)系数显著(P<0.05)提高0.01百分点,T1组肾脏系数显著提高0.08百分点,但心、肝、肺的脏器系数无显著差异。T1组北京鸭的胸肌黄度(b^(*))值较CK显著降低,但3组的其余肉质性状检测指标均无显著差异。T1组北京鸭的碱性磷酸酶(ALP)、酸性磷酸酶(ACP)活性分别较CK显著降低22.02%、21.42%,但3组北京鸭的其余血清生化指标均无显著差异。与CK相比,T1组北京鸭血清的补体C3、补体C4、干扰素-γ(IFN-γ)、白细胞介素2(IL-2)、免疫球蛋白A(IgA)、免疫球蛋白G(IgG)、免疫球蛋白M(IgM)、分泌型免疫球蛋白A(sIgA)含量均显著升高,T2组北京鸭血清中的sIgA、IL-2和C3含量显著升高。总的来看,用10%或30%的BSFL代替豆粕作为家禽饲料的蛋白质对北京鸭进行饲喂具有可行性。