gdk-pixbuf2.tcz is what now handles the pixbuf stuff, that file has been deprecated and is no longer used or needed, so adding it back should make no difference. The relevant file now is:
/usr/local/lib/gdk-pixbuf-2.0/2.10.0/loaders.cache
When I run that command, I see no error. Here is the contents of that file on my box:
# GdkPixbuf Image Loader Modules file
# Automatically generated file, do not edit
# Created by gdk-pixbuf-query-loaders from gdk-pixbuf-2.22.1
#
# LoaderDir = /usr/local/lib/gdk-pixbuf-2.0/2.10.0/loaders
#
"/usr/local/lib/gdk-pixbuf-2.0/2.10.0/loaders/libpixbufloader-svg.so"
"svg" 2 "gdk-pixbuf" "Scalable Vector Graphics" "LGPL"
"image/svg+xml" "image/svg" "image/svg-xml" "image/vnd.adobe.svg+xml"
"text/xml-svg" ""
"svg" ""
" <svg" "* " 100
" <!DOCTYPE svg" "* " 100
"/usr/local/lib/gdk-pixbuf-2.0/2.10.0/loaders/libpixbufloader-xpm.so"
"xpm" 4 "gdk-pixbuf" "The XPM image format" "LGPL"
"image/x-xpixmap" ""
"xpm" ""
"/* XPM */" "" 100
"/usr/local/lib/gdk-pixbuf-2.0/2.10.0/loaders/libpixbufloader-xbm.so"
"xbm" 4 "gdk-pixbuf" "The XBM image format" "LGPL"
"image/x-xbitmap" ""
"xbm" ""
"#define " "" 100
"/*" "" 50
"/usr/local/lib/gdk-pixbuf-2.0/2.10.0/loaders/libpixbufloader-wbmp.so"
"wbmp" 4 "gdk-pixbuf" "The WBMP image format" "LGPL"
"image/vnd.wap.wbmp" ""
"wbmp" ""
" " "zz" 1
" `" "z " 1
" @" "z " 1
" " "z " 1
"/usr/local/lib/gdk-pixbuf-2.0/2.10.0/loaders/libpixbufloader-tiff.so"
"tiff" 1 "gdk-pixbuf" "The TIFF image format" "LGPL"
"image/tiff" ""
"tiff" "tif" ""
"MM *" " z " 100
"II* " " z" 100
"II* \020 CR\002 " " z zzz z" 0
"/usr/local/lib/gdk-pixbuf-2.0/2.10.0/loaders/libpixbufloader-tga.so"
"tga" 4 "gdk-pixbuf" "The Targa image format" "LGPL"
"image/x-tga" ""
"tga" "targa" ""
" \001\001" "x " 100
" \001\t" "x " 100
" \002" "xz " 99
" \003" "xz " 100
" \n" "xz " 100
" \013" "xz " 100
"/usr/local/lib/gdk-pixbuf-2.0/2.10.0/loaders/libpixbufloader-ras.so"
"ras" 4 "gdk-pixbuf" "The Sun raster image format" "LGPL"
"image/x-cmu-raster" "image/x-sun-raster" ""
"ras" ""
"Y\246j\225" "" 100
"/usr/local/lib/gdk-pixbuf-2.0/2.10.0/loaders/libpixbufloader-qtif.so"
"qtif" 4 "gdk-pixbuf" "The QTIF image format" "LGPL"
"image/x-quicktime" "image/qtif" ""
"qtif" "qif" ""
"abcdidsc" "xxxx " 100
"abcdidat" "xxxx " 100
"/usr/local/lib/gdk-pixbuf-2.0/2.10.0/loaders/libpixbufloader-pnm.so"
"pnm" 4 "gdk-pixbuf" "The PNM/PBM/PGM/PPM image format family" "LGPL"
"image/x-portable-anymap" "image/x-portable-bitmap" "image/x-portable-graymap"
"image/x-portable-pixmap" ""
"pnm" "pbm" "pgm" "ppm" ""
"P1" "" 100
"P2" "" 100
"P3" "" 100
"P4" "" 100
"P5" "" 100
"P6" "" 100
"/usr/local/lib/gdk-pixbuf-2.0/2.10.0/loaders/libpixbufloader-png.so"
"png" 5 "gdk-pixbuf" "The PNG image format" "LGPL"
"image/png" ""
"png" ""
"\211PNG\r\n\032\n" "" 100
"/usr/local/lib/gdk-pixbuf-2.0/2.10.0/loaders/libpixbufloader-pcx.so"
"pcx" 4 "gdk-pixbuf" "The PCX image format" "LGPL"
"image/x-pcx" ""
"pcx" ""
"\n \001" "" 100
"\n\002\001" "" 100
"\n\003\001" "" 100
"\n\004\001" "" 100
"\n\005\001" "" 100
"/usr/local/lib/gdk-pixbuf-2.0/2.10.0/loaders/libpixbufloader-jpeg.so"
"jpeg" 5 "gdk-pixbuf" "The JPEG image format" "LGPL"
"image/jpeg" ""
"jpeg" "jpe" "jpg" ""
"\377\330" "" 100
"/usr/local/lib/gdk-pixbuf-2.0/2.10.0/loaders/libpixbufloader-ico.so"
"ico" 5 "gdk-pixbuf" "The ICO image format" "LGPL"
"image/x-icon" "image/x-ico" "image/x-win-bitmap" ""
"ico" "cur" ""
" \001 " "zz znz" 100
" \002 " "zz znz" 100
"/usr/local/lib/gdk-pixbuf-2.0/2.10.0/loaders/libpixbufloader-icns.so"
"icns" 4 "gdk-pixbuf" "The ICNS image format" "GPL"
"image/x-icns" ""
"icns" ""
"icns" "" 100
"/usr/local/lib/gdk-pixbuf-2.0/2.10.0/loaders/libpixbufloader-gif.so"
"gif" 4 "gdk-pixbuf" "The GIF image format" "LGPL"
"image/gif" ""
"gif" ""
"GIF8" "" 100
"/usr/local/lib/gdk-pixbuf-2.0/2.10.0/loaders/libpixbufloader-bmp.so"
"bmp" 5 "gdk-pixbuf" "The BMP image format" "LGPL"
"image/bmp" "image/x-bmp" "image/x-MS-bmp" ""
"bmp" ""
"BM" "" 100
"/usr/local/lib/gdk-pixbuf-2.0/2.10.0/loaders/libpixbufloader-ani.so"
"ani" 4 "gdk-pixbuf" "The ANI image format" "LGPL"
"application/x-navi-animation" ""
"ani" ""
"RIFF ACON" " xxxx " 100