Är fång ärftligt?

[Account]

Googlade frågan och fick bara upp träffar som är 6-10 år gamla. Hur ser forskningen ut nuförtiden? Är fång ärftligt eller inte?

 

[Korven]

Dispositionen för fång skulle inte förvåna mig.

 

[Centaur]

Vissa raser är predisponerade pga att de bär gener för EMS vilket i sin tur är en vanlig orsak till fång, så ja på det sättet är fång ärftligt.

Men med tanke på att nästan alla ponnyraser har det i generna är det inget som man direkt kan avla bort.

 

[MissFideli]

Kanske inte fång i sig, men vissa av sakerna som kan orsaka fång troligen.

 

[animalasia]

Det forskas mycket på fång och vad som orsakar det samt hur det skall förebyggas så jag hoppas att vi kommer få mer kunskap inom detta område snart. För avelsarbetet är det extra viktigt.

 

[Sar]

Jag klipper in ett av mina tidigare svar från ett annat forum. Den här undersökningen gjordes för 10 år sedan så jag vet inte om det skett nyare fynd som motsäger detta. Fång kommer ju även av miljöorsaker men en viss ärftlig disposition verkar finnas.
Jag klipper in lite från en artikel från 2006 (hittade tyvärr ingen översatt).

"Underlying Causes of Laminitis

Recent work has shed light on some of the underlying causes of pasture-associated laminitis.

Workers at the Virginia Polytechnic Institute and State University in Blacksburg, Virginia have identified a prelaminitic metabolic syndrome (PLMS) in apparently healthy ponies. They studied a group of ponies, some of which had previously had laminitis (the PL group) and some with no history or signs of laminitis (the NL group).

Kibby Treiber and her colleagues found that ponies that went on to develop laminitis had different metabolic characteristics from those that did not. Animals at risk for laminitis had insulin resistance, raised blood insulin levels, and alterations in glucose and fat metabolism. [Editor’s Observation: these characteristics, and other factors described further in this article, appear to be similar to the characteristics associated with diabetes in humans.]

A herd of 160 ponies was used for the study. Overall, 34% of the ponies had signs of laminitis. Only 6% of mature stallions were affected compared with 52% of mature mares.

Ponies in the PL group had significantly higher condition scores that did the NL group. They tended to have well-developed fatty tissue pads along the crest and at the shoulder and tail head.

The researchers defined PLMS (see box below) by assessing body scores and looking at insulin resistance. Rather than use one of the more specific tests for insulin resistance they used a “proxy” or simplified measure, which although not as precise as the more complex tests was sufficiently accurate to identify abnormalities. From a single blood sample, they measured blood glucose, insulin, and triglyceride concentrations. Using these results, they calculated proxies for insulin sensitivity (expressed as the reciprocal of the square root of insulin, RIQSI) and insulin secretory response (expressed as modified insulin to glucose ratio, MIRG).


RISQI = [insulin] -0.5

MIRG = (800 - 0.3 x [insulin]2 ) / ([glucose] - 30)

Where [insulin] is the basal insulin concentration in mU/L and [glucose] is the basal glucose concentration in mg/dL

Prelaminitic metabolic syndrome (PLMS) in healthy ponies is present when three or more of the following conditions are met:

RISQI < 0.32

MIRG > 5.6

Blood triglyceride concentration > 57.0mg/dL

Obesity (body condition score > 6.0)

They identified 62 ponies with PLMS and 98 that did not have PLMS. Two months later, the carbohydrate levels in the pasture where the ponies were kept had risen, and 13 ponies developed laminitis. Eleven of the affected ponies were in the PLMS group, and only two were in the non-PLMS group. This indicated the ponies in the PLMS group were ten times more likely to develop laminitis than were the non-PLMS ponies.

The researchers also found evidence that the predisposition to laminitis was inherited. Nearly all ponies with signs of laminitis had been born to mares in the PL group. Analysis of breeding records going back 5-10 generations revealed evidence of a possible genetic predisposition for laminitis. The prevalence of laminitis was consistent with that expected from a dominant gene or genes, with reduced penetrance, associated with age, sex, and other factors.

Ms. Treiber suggests that identifying ponies with PLMS allows them to be managed with special care. This may reduce the risk of them developing laminitis. For example, ponies with PLMS should not be fed on high starch diets to reduce the risk of obesity and insulin resistance.

In addition, PLMS might influence the market value of ponies. Paradoxically, ponies with PLMS have qualities that show judges and breeders prefer.



© 2006 Equine Science Update

Reprinted with permission

www.equinescienceupdate.co.uk"