[Objective]The paper was to study the effects of lactobacillus microecologics on production performance,immune function and intestinal microflora of egg chicks.[Method]Totally 18001-day-old chicks of Hyline brown were...[Objective]The paper was to study the effects of lactobacillus microecologics on production performance,immune function and intestinal microflora of egg chicks.[Method]Totally 18001-day-old chicks of Hyline brown were randomly divided into three groups,four repeats each group and 150 chicks each repeat.The chicks in control group were supplied with basic diet,and those in experimental groups I and II were supplied with the basic diet added with 100 and 150 g/t microecologics,respectively.[Result]Compared with the control group,the daily gain of egg chicks in experimental group II after 7 weeks was increased by 3.67%(P<0.05),and the feed conversion ratio was significantly reduced by 0.05(P<0.05);the thymus indexes in experimental groups I and II were significantly improved by 4.95%and 5.94%(P<0.05),and the spleen indexes were significantly improved by 3.32% and 4.36% compared with the control group(P<0.05).The index of bursa of fabricius in experimental group II was extremely improved by 9.66%compared with the control group(P<0.01).Meantime,experimental group II extremely improved the number of living lactobacillus in caecum of egg chicks(P<0.01),and extremely reduced the number of Escherichia coli in caecum(P<0.01).[Conclusion]Lactobacillus microecologics are beneficial to the improvement of production performance,immune function and intestinal flora of egg chicks.The optimal addition amount in the feed of chicks is 150 g/t.展开更多
Background: In coevolutionary interactions between brood parasites and their hosts, host parents are under strong selection to evolve defenses against parasitism. Egg rejection is an efficient and common defense again...Background: In coevolutionary interactions between brood parasites and their hosts, host parents are under strong selection to evolve defenses against parasitism. Egg rejection is an efficient and common defense against parasitism, although some apparently suitable hosts do not reject cuckoo eggs.Methods: Sparrows Ploceidae are widespread throughout the Old World, and they have a suitable diet for rearing cuckoos, but still they are rarely exploited by brood parasites. To solve such puzzle, we conducted artificial parasitism and cross-fostering experiments in Russet Sparrow(Passer cinnamomeus).Results: The present study showed that Russet Sparrows have no egg recognition ability, but recognize their own nestlings and eject alien chicks or starve them to death. They may use visual cues in chick recognition, although they accept sister species Tree Sparrow(Passer montanus).Conclusions: By rejecting nestlings of foreign species, Russet Sparrows have succeeded to escape from the brood parasitism by cuckoos and other parasites. Our studies shed light on the puzzle why some species are not utilized by cuckoo parasites as hosts.展开更多
基金Supported by Leading Project of Fujian Provincial Department of Science and Technology(2019Y6005)Innovation Fund Project of Fujian Provincial Department of Science and Technology(2018C0041)
文摘[Objective]The paper was to study the effects of lactobacillus microecologics on production performance,immune function and intestinal microflora of egg chicks.[Method]Totally 18001-day-old chicks of Hyline brown were randomly divided into three groups,four repeats each group and 150 chicks each repeat.The chicks in control group were supplied with basic diet,and those in experimental groups I and II were supplied with the basic diet added with 100 and 150 g/t microecologics,respectively.[Result]Compared with the control group,the daily gain of egg chicks in experimental group II after 7 weeks was increased by 3.67%(P<0.05),and the feed conversion ratio was significantly reduced by 0.05(P<0.05);the thymus indexes in experimental groups I and II were significantly improved by 4.95%and 5.94%(P<0.05),and the spleen indexes were significantly improved by 3.32% and 4.36% compared with the control group(P<0.05).The index of bursa of fabricius in experimental group II was extremely improved by 9.66%compared with the control group(P<0.01).Meantime,experimental group II extremely improved the number of living lactobacillus in caecum of egg chicks(P<0.01),and extremely reduced the number of Escherichia coli in caecum(P<0.01).[Conclusion]Lactobacillus microecologics are beneficial to the improvement of production performance,immune function and intestinal flora of egg chicks.The optimal addition amount in the feed of chicks is 150 g/t.
基金supported by the National Natural Science Foundation of China(Nos.31672303 to CY,31472013 and 31772453 to WL)
文摘Background: In coevolutionary interactions between brood parasites and their hosts, host parents are under strong selection to evolve defenses against parasitism. Egg rejection is an efficient and common defense against parasitism, although some apparently suitable hosts do not reject cuckoo eggs.Methods: Sparrows Ploceidae are widespread throughout the Old World, and they have a suitable diet for rearing cuckoos, but still they are rarely exploited by brood parasites. To solve such puzzle, we conducted artificial parasitism and cross-fostering experiments in Russet Sparrow(Passer cinnamomeus).Results: The present study showed that Russet Sparrows have no egg recognition ability, but recognize their own nestlings and eject alien chicks or starve them to death. They may use visual cues in chick recognition, although they accept sister species Tree Sparrow(Passer montanus).Conclusions: By rejecting nestlings of foreign species, Russet Sparrows have succeeded to escape from the brood parasitism by cuckoos and other parasites. Our studies shed light on the puzzle why some species are not utilized by cuckoo parasites as hosts.
