Coat Colour. Lakeland Terrier

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Samuel Edwards
5 years ago
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1 A Discussion of Coat Colour Gntics in th Lakland Trrir Chaptr 7 Rd By Ron Puntr

Rd -Whatn gn To mak it absolutly clar at th start -all th Laklands that I hav sn in rcnt yars ar rcssiv mating two togthr will always produc only rd puppis. Rd is vry variabl and at on xtrm is cram.

2 Rd -Whatn gn To mak it absolutly clar at th start -all th Laklands that I hav sn in rcnt yars ar rcssiv mating two togthr will always produc only rd puppis. Rd is vry variabl and at on xtrm is cram. Gnticists hav oftn mad th rronous dfault assumption that, lik Irish Trrirs, Rd Laklands would by A y. In this situation th A y - and ar mimicking ach othr xcpt for th fact that pups ar born solid rd and th A y usually hav som sabl suffusion that fads as thy matur. Rcssiv rd is traditionally namd th xtnsion sris. A y is dominant to Saddl Pattrn so supposing a Rd Lakland which was also carrying rcssiv rd ( A y a s a E ) was matd to a rcssiv rd hiding saddl ( a sa a sa ) Th two st of allls can assort in th following ways: a sa a sa A y A y a sa A y a sa a sa a sa a sa a sa a sa E E E Pag 2

3 It s fairly obvious how th two sts of allls can combin without drawing a chart but just for illustration purposs hr it is. E E A y a sa A y a sa E A y a sa E A y a sa A y a sa A y a sa A y a sa E A y a sa E A y a sa A y a sa a sa a sa a sa a sa E a sa a sa E a sa a sa a sa a sa a sa a sa a sa a sa E a sa a sa E a sa a sa a sa a sa Th 16 possibilitis givs 4 diffrnt combinations in qual proportions: Sub totals proportion A y a sa E dominant Rd carrying rcssiv rd 4 1/4 A y a sa rcssiv Rd carrying dominant rd 4 1/4 a sa a sa rcssiv Rd 4 1/4 a sa a sa E Saddl Pattrn 4 1/4 Totals 16 1 So on avrag 3/4 of th pups will b Rd and 1/4 saddl pattrn. If on parnt was A y a sa E and th othr A y a sa thr would only b a 1/8 chanc of a Saddl Pattrn If that s not so obvious draw th chart out to chck. Irish Trrir Puppis ar gnrally born with black tips to many of th rd hairs this is typical of th Ay gn. Slctiv brding for htrozygous ovr many gnrations has nsurd that no Saddl Pattrn Irish ar born nowadays. Stripping away th puppy coat rvals a solid rd. Th tail and bard ar th last to clar. Rd and Whit Fox Trrirs ar also A y. Pag 3

4 Thr is no way to tll visually what Agouti sris gns a rcssiv Lakland is hiding, but gntic tsting may bcom availabl. ~ In th cas of mating a Saddl Pattrn carrying rd to a rcssiv rd only th xtnsion sris nds to b considrd to prdict possibility of rd puppis. If th Saddl Pattrn parnt is carrying rd () E E Saddl Pattrn E Saddl Pattrn Rd Rd 1/2 of th puppis will b Rd and th othr 1/2 Saddl Pattrn but if th saddl Pattrn dosn't carry th gn non can b Rd: E E Saddl Pattrn E Saddl Pattrn E E Saddl Pattrn E Saddl Pattrn Pag 4 This champion Rd looks vry lgant and striking in th ring but Rds always look a shad longr compard to a Saddl Pattrn and judgs should b awar of this othrwis thr will b a tndncy to brd Rds that ar too short rathr than modratly short as rquird by th standard.

5 Mor rds than would b xpctd on avrag in this small sampl of thr littrs with on rd parnt and a carrir parnt. Ovr a largr sampl it should avrag out at 50:50. If it dosn't thn thr is som bias acting in favour of Rds, prhaps a lthal gn of som sort in Saddl Pattrn. Avrag littr siz in Laklands is low at only 3.4. could it b significant that ths larg littrs hav xtra rds? Thoughts lik this go through a brdrs mind but gnrally it will avrag out. Somtims w only gt on pup. Somtims w gt littrs of all on sx but sx dos dfinitly avrag out 50:50 ovr a lot of littrs. Thr ruls for all rcssiv allls can b discrnd from brding rds: If a Saddl Pattrn has a rd parnt it will b carrying rd. If a Saddl Pattrn brds vn just on rd it is a known carrir but if it nvr brds on it dosn't prov that it s not a carrir. Pag 5

6 If two Saddl Pattrn parnts brd a Rd thy must both b carrirs and this clarly dmonstrats that in th cas of a hiddn problm coming out it s silly to try to plad It s not coming from my dog. How Rd is Rd? Whthr a Lakland is solid rd as opposd to saddl pattrn is du to a singl gn but it s oftn spculatd that th strngth of colour is th rsult of anothr st of gns originally thought of as Rufus polygns producing an incras in rddning and now, coming from th opposit dirction of a dcras, th I phomlanin dilution sris is suggstd. Probably this is unlikly and it s mor to do with switchs alongsid th allis rsponding in an un-uniform mannr but at th momnt this is all spculation. Popl hav somtims attmptd to produc grads of colour that might indicat a sris of gns but I hav nvr bn abl to dtct stp changs in any of th vry variabl charactristics (will discuss this mor undr Saddl Pattrn.) As it dosn't actually mattr what shad a Lakland is thr's not vn any incntiv to slct for a light or dark Rd (unlss you hav a prsonal prfrnc.) In a way I m writing about this at a difficult tim whn knowldg is advancing rapidly but thr ar still many qustions to b answrd about th dog gnom it might wll b that a dfinit mchanism for th intnsity of rd is soon discovrd. Whn a buyr rqustd a Whatn pup my knnl partnr s y and min didn't vn agr on a puppy w had, h thought of it as light rd and I said it would pass as whatn anyway th popl wr dlightd with him -h was just what thy wr wanting, basically not a dark rd. Although th standard says that rich tan is undsirabl on a Saddl Pattrn (w would considr such a colour as mor appropriat to th Wlsh Trrir) thr is no such rstriction with a solid Rd and popl could vn b ntitld to think th rddr th bttr if that s thr prfrnc. Tan and Rd ar diffrnt nams for Yllow pigmnt but I m not at all sur that Rd Laklands ar th sam shad of Tan that a individual would hav had in a Saddl Pattrn (if th allls hadn't rmovd th black) Looks to m that somthing ls is causing th solid colour to vary mor than tan dos but that again is brdrs spculation. Anyway until somon coms up with dfinitiv answrs I will just say: Rd is vry variabl. Pag 6

Dudly Nos : is usd as a pjorativ -applid to lack of skin pigmnt. Rally it s a misnomr, popularisd by Rowdn L in Modrn Dogs 1894.

cas. Sunlight stimulats th production of skin pigmnt- Wintr Nos is thrfor slf xplanatory.

7 Dudly Nos : is usd as a pjorativ -applid to lack of skin pigmnt. Rally it s a misnomr, popularisd by Rowdn L in Modrn Dogs ( wouldn't think posh Rowdn L had vr bn anywhr nar industrial Dudly) Originally it cam from a much admird 1877 livr colourd Bulldog calld Lord Dudly who had a livr nos which was not a fault in his cas. Sunlight stimulats th production of skin pigmnt- Wintr Nos is thrfor slf xplanatory. It was oftn thought that Rds tndd to hav poor pigmntation, that's not gnrally bn my xprinc although thy tnd not to hav much pigmnt whn born thy can soon colour up (somtims waitd with batd brath though!) Th pictur abov was takn whn th pups wr about a wk old and just bginning to gt som colour in thir noss. Th sam pups at 6 wks old (my how thy grow!) pictur spaks for it s slf -vry bst of pigmnt. Evn in th foot pads Rds oftn hav at last as good pigmnt as Black and Tans and oftn bttr. Pag 7

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