Internal Fertilization In The Catfish Family

[jollysue]

Can someone help to translate this for me? It is an incomplete study, I believe, applying most specifically to the suspected sperm drinking Catfish.

Journal of Fish Biology
Volume 70 Issue 1 Page 243-256, January 2007
To cite this article: C. MAZZOLDI, V. LORENZI, M. B. RASOTTO (2007) Variation of male reproductive apparatus in relation to fertilization modalities in the catfish families Auchenipteridae and Callichthyidae (Teleostei: Siluriformes)
Journal of Fish Biology 70 (1) , 243?256 doi:10.1111/j.1095-8649.2006.01300.x

Abstract
To investigate the relationship between fertilization modalities and the morphology of male reproductive apparatus, two species of Auchenipteridae, Auchenipterus nuchalis and Tatia intermedia, and six species of Callichthyidae, Callichthys callichthys, Corydoras aeneus, Corydoras bondi, Corydoras ehrhardti, Corydoras potaroensis and Hoplosternum littorale were studied. The species analysed show either internal or external fertilization, the latter including the so called ?sperm drinking? type of mating. An anal fin modified as an intromittent organ, a pair of seminal vesicles, and the release of sperm in the form of discrete bundles (spermatozeugmata) characterize the male reproductive apparatus of the internal fertilizer A. nuchalis. Seminal vesicles are present also in C. aeneus, C. bondi, C. ehrhardti, C. potaroensis and H. littorale, species performing ?sperm drinking? spawning. In contrast, regardless of the family, species showing the more classic type of external fertilization lack specialized accessory organs. Where occurring, the major function of seminal vesicles is the secretion of mucins. The role of these mucosubstances, in relation to spermatozeugmata formation, in internal fertilizers, or the protection of sperm passing through the female gut, in the ?sperm-drinking? species, is discussed. Variation, between families, in the shape of testis and accessory structures, as well as in the type of spermatogenesis was found. Neither the reproductive modalities nor the phylogenetic relationships, however, appear to fully account for these differences

Perhaps I am very behind and have missed a discussion. If so can you link me?

sue

 

[OohFeeshy]

Ah... That is veeery interesting. All you needed was to stick ' Callichthyidae sperm drinking' into Google scholar to find

We report on unique reproductive behaviour and a new mode of egg insemination in a small catfish Corydoras aeneus (Callichthyidae). A male courts a female by presenting his abdomen to her. Before releasing eggs, the female attaches her mouth to the male''s genital opening and directly drinks his sperm. The sperm pass through her intestine and are discharged together with eggs into the pouch formed by her pelvic fins. Thus, eggs are mixed with fresh non-dispersed sperm in an enclosed space, ensuring effective insemination. This mode of insemination is novel to fishes, but is likely not restricted to catfishes of the genus Corydoras.

The Journal of Fish Biology one is complete, but you need to pay to see it. All it really says is that they looked at some cories, which carry out external fertilization, and some wood cats, which carry out internal fertilization (not sure if they all do), and compared their sexual organs and gamtes. The wood cats have a modified anal fin like guppies. Along with the sperm, mucusy secretions protect the sperm when going through the digestive system in cories, and they discuss what happens in the wood cats.

 

[steelhealr]

I think we should give OohFeeshy an honorary appointment here. There I was...ready to translate...and all Ooh did was Google. WTG. SH

 

[jollysue]

That seems to be pretty much what I thought it said. Although because of the question marks around "sperm drinking," I am assuming that they do not have conclusive evidence of that yet. There is some theory/scientific study in progress

I will watch for the rest of this to show up and bring it over when it becomes available--or if you find it let me know. This is really interesting to those of us breeding Corys. Prior to now it has been theorized that there was sperm drinking among the Corydoras, but not confirmed or believed by many. LOL

Oh dear how off topic this could get!

Oh yes! applause and honors to Ooh!

 

[OohFeeshy]

No problemo.

RE the question marks around the sperm drinking, there aren't any- it's in quotation marks. So I presume, and from the language in the other bit, that it's a definite- explains the 't' position, at any rate. It makes sense though, the sperm is passed through the digestive system, protected by mucus, and comes out at the right place to fertilize the eggs. It's likely to be more efficient than other methods.

 

[Coryologist]

No problemo.

RE the question marks around the sperm drinking, there aren't any- it's in quotation marks. So I presume, and from the language in the other bit, that it's a definite- explains the 't' position, at any rate. It makes sense though, the sperm is passed through the digestive system, protected by mucus, and comes out at the right place to fertilize the eggs. It's likely to be more efficient than other methods.

This has been totally debunked and is extremely implausible if given any logical thought. Ian Fuller can give you all of the details and he has informed me that he will be removing all information pertaining to this study from the updated edition of his breeding book. It just ain't true. - Frank

 

[ICEEGRL]

So what is true if that isn't?

 

[mike os]

No problemo.

RE the question marks around the sperm drinking, there aren't any- it's in quotation marks. So I presume, and from the language in the other bit, that it's a definite- explains the 't' position, at any rate. It makes sense though, the sperm is passed through the digestive system, protected by mucus, and comes out at the right place to fertilize the eggs. It's likely to be more efficient than other methods.

This has been totally debunked and is extremely implausible if given any logical thought. Ian Fuller can give you all of the details and he has informed me that he will be removing all information pertaining to this study from the updated edition of his breeding book. It just ain't true. - Frank

OLd thread....


As above ...totally implausible...especially to anyone who has actually watched corys breed...