## 4 Discussion
### Extracted Sheep Wool Volatiles and Their Activity against Mosquito  
Most of the volatile compounds we identified from sheep wool (Tables 1 and 2) were found previously in sheep-derived products and reported in the literature [8; 10; 11; 12; 30; 31; 32; 33; 34; 35; 36; 37; 38; 39; 40; 41; 42; 43]. This set includes those aldehydes, potent attractants for RVFV mosquito vectors--heptanal, octanal, nonanal, decanal [8]. Among the semiochemicals used by mosquitoes during mating, oviposition, host-seeking, and/or sugar feeding are the compounds: 2-ethyl hexanol, \(p\)-cresol, hexanal, heptanal, octanal, nonanal, decanal, benzaldehydehyde, \(\beta\)-caryophyllene, and phenol [8; 48; 49; 50; 51; 52; 53; 54; 55; 56; 57; 58; 59]. Various insects including mosquitoes were attracted to dodecane [59]. 2-Hexanone and 1-butanol showed mosquito attractant activity [60], and 2-octanone showed attractancy against _Culex pipiens_ (Diptera: Culicidae) [61]. Octanal was attractive to _Ae. aegypti_ mosquitoes [62] and octanal, nonanal, and decanal, in olfactometer trials, interfered with the attraction of species to a host [63]. [PERSON] et al. (2005) identified several compounds from plant extracts, including longifolene and caryophyllene, as attractants for oviposition of _Anopheles albimanus_ (Diptera: Culicidae) [64]. An increased attraction of _An. stephensi_ (Diptera: Culicidae) was observed for 3-methylbutanoic acid, 2-methylbutanoic acid, hexanoic acid, and tridecane [65]. Hexadecane along with a group of other compounds significantly reduced trap catches of _An. arabiensis_ (Diptera: Culicidae) compared to a negative control [66]. \(\beta\)-Caryophyllene and decanal elicited antennal responses from _An. arabiensis_ during gas chromatography coupled to electroantennographic detection (GC-EAD) experiments [48]. Electroantennograms recorded with _Toxorhvnites motezuma_ (Diptera: Culicidae) and _T. amboinensis_ (Diptera: Culicidae) mosquitoes for phenol, \(m\)-cresol, \(p\)-cresol (along with several other compounds) showed oviposition attractancy [67]. Hexanal showed EAD-activity against _An. gambiae_ (Diptera: Culicidae) [51]. The study conducted by [PERSON] et al. [53] revealed an increase in attraction of _An. gambiae_ towards a synthetic blend containing heptanal, nonanal and, octanal. The compounds 3-hexanol, 1-hexanol, and 1-pentanol activate CO\({}_{2}\)-sensitive olfactory neurons in _Ae. aegypti_ and _An. gambiae_[68]. Higher amounts of 2-methylbutanoic acid and octanal, along with two other compounds, were associated with individuals that were highly attractive to _An. gambiae_[69]. Isoamyl alcohol was among the six most promising candidate oviposition semiochemicals (_An. gambiae_) out of 50 identified volatiles that were emitted from the headspace of the most attractive bacteria isolates [70]. According to these literature studies [8; 10; 11; 12; 30; 31; 32; 33; 34; 35; 36; 37; 38; 39; 40; 41; 42; 43; 44; 45; 46; 47; 48; 49; 50; 51; 52; 53; 54; 55; 56; 57; 58; 59; 60; 61; 62; 63; 64; 65; 66; 67; 68; 69], many constituents of sheep wool (Tables 1 and 2), showed attractant activity against mosquitoes. Aldehydes that were active against mosquitoes: hexanal, heptanal, octanal, nonanal, decanal, and benzaldehyde [8; 10; 11; 12; 30; 31; 32; 33; 34; 35; 36; 62; 63; 69] were present in a pHS extract of sheep wool at \(\sim\)18.2% (nonanal, octanal, and decanal), and \(\sim\)10.6% (nonanal), detected by GC-MS, and GC-FID/GC-MS, correspondingly; in HS-SPME collections, by PDMS/DVB, and CAR/PDMS they were present at \(\sim\)36.2% and 36.4% (heptanal, hexanal, nonanal, octanal, and benzaldehyde), correspondingly, and by PDMS \(\sim\) 6.6% (nonanal), detected by GC-FID/GC-MS (Tables 1 and 2).