Paenibacillus thiaminolyticus is not the cause of thiamine deficiency impeding lake trout (Salvelinus namaycush) recruitment in the Great Lakes

Abstract

Thiamine (vitamin B1) deficiency is a global concern affecting wildlife, livestock, and humans. In Great Lakes salmonines, thiamine deficiency causes embryo mortality and is an impediment to restoration of native lake trout ( Salvelinus namaycush ) stocks. Thiamine deficiency in fish may result from a diet of prey with high levels of thiaminase I. The discoveries that the bacterial species Paenibacillus thiaminolyticus produces thiaminase I, is found in viscera of thiaminase-containing prey fish, and causes mortality when fed to lake trout in the laboratory provided circumstantial evidence implicating P. thiaminolyticus. This study quantified the contribution of P. thiaminolyticus to the total thiaminase I activity in multiple trophic levels of Great Lakes food webs. Unexpectedly, no relationship between thiaminase activity and either the amount of P. thiaminolyticus thiaminase I protein or the abundance of P. thiaminolyticus cells was found. These results demonstrate that P. thiaminolyticus is not the primary source of thiaminase activity affecting Great Lakes salmonines and calls into question the long-standing assumption that P. thiaminolyticus is the source of thiaminase in other wild and domestic animals.

Fatty‐acid profiles of juvenile lake trout reflect experimental diets consisting of natural prey

“…Early foraging has been suggested as a means to compensate for maternally derived thiamine deficiencies (Ladago et al, 2016). As prey species differ in their thiamine content (Tillitt et al, 2005;Richter et al, 2012), monitoring what items comprise diets of juvenile lake trout in stocks experiencing thiamine deficiencies is of interest. Copepods comprised a large portion (20-30% numerically) of age-0 (<30 mm) lake trout diets in Lake Champlain, while diets of similar sized lake trout in Lake Huron were dominated by chironomids (>69% by volume; Swedberg & Peck, 1984;Ladago et al, 2016).…”

Factors Affecting Postrelease Survival of Coded‐Wire‐Tagged Lake Trout in Lake Michigan at Four Historical Spawning Locations

“…Alewife are thought to interfere with Lake Trout recruitment by preying on Lake Trout fry 886 O'Gorman et al 2000;Madenjian et al 2008) and by causing a thiamine deficiency in Lake Trout that heavily feed on Alewife, which reduces the survival of eggs and larvae (thiamine deficiency complex [TDC]; Fitzsimons and Brown 1998;Brown et al 2005;Honeyfield et al 2005). Thiamine deficiency complex, among other factors that often are not considered or are dismissed (e.g., predation on Lake Trout eggs; Chotkowski and Marsden 1999;Jonas et al 2005), has been suggested as a major impediment to Lake Trout restoration (Bronte et al 2003b;Riley et al 2011), but the study of TDC in the Great Lakes is relatively recent and the mechanisms and relative importance of TDC as an impediment relative to Alewife predation on fry are debatable (see Richter et al 2012;Ladago et al 2016).…”

Clupeid Response to Stressors: The Influence of Environmental Factors on Thiaminase Expression

“…Thiaminase activity in Alewives has been attributed to thiaminase positive bacteria Paenibacillus thiaminolyticus isolated from Alewife viscera (Honeyfield et al 2002), though Richter et al (2012) reported that this bacteria is not the primary source of thiaminase activity. Thus, there is some debate over whether the ultimate source of thiaminase in fish is the fish themselves (Riley and Evans 2008;Richter et al 2012), thiaminolytic bacteria (Honeyfield et al 2002), other sources, or a combination of these sources.…”

“…Thiaminase activity in Alewives has been attributed to thiaminase positive bacteria Paenibacillus thiaminolyticus isolated from Alewife viscera (Honeyfield et al 2002), though Richter et al (2012) reported that this bacteria is not the primary source of thiaminase activity. Thus, there is some debate over whether the ultimate source of thiaminase in fish is the fish themselves (Riley and Evans 2008;Richter et al 2012), thiaminolytic bacteria (Honeyfield et al 2002), other sources, or a combination of these sources. Nevertheless, the presence of thiaminase in Alewives is believed to be a primary factor responsible for TDC in predators of the Alewife (Fitzsimons et al 1999;Honeyfield et al 2005a) even though thiamine deficiency has not been observed within clupeids containing high thiaminase activity (Wistbacka et al 2002;Tillitt et al 2005).…”

“…Laboratory experiments have induced TDC in Lake Trout by altering dietary levels of thiaminase, using feral Alewives containing thiaminase and bacterial sources of thiaminase (Honeyfield et al 2005b). Although the ultimate source or sources of thiaminase contributing to TDC are unknown in natural systems (Richter et al 2012), available evidence suggests that clupeid or bacterial thiaminase, or both, play a key role in the development of salmonine thiamine deficiency.…”