Silo propanoolisisaldus ja selle seos teiste fermentatsiooninäitajatega
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Kuupäev
2016
Kättesaadav alates
Autorid
Ajakirja pealkiri
Ajakirja ISSN
Köite pealkiri
Kirjastaja
Abstrakt
Propionaat mängib olulist rolli mäletsejate metabolismis ning ratsiooni koostamisel oleks vaja
arvestada kõiki propionaadi allikaid. Propanool on lähteaine propioonaadiks, kuid silo rutiinsel
analüüsil seda sageli ei määrata. Magistritöö eesmärgiks oli määrata propanoolisisaldus nii
rohu- kui maisisilodes ning leida seoseid propanooli ja teiste silo fermentatsiooni näitajate
vahel. Antud uurimistöö raames analüüsiti ühe aasta jooksul 1687 siloproovi. Liskas
fermentatsiooninäitajatele määrati silodest ka propanooli- ja isopropanoolisisaldus. Keskmised
propanooli-, propüleenglükooli- ja propioonhappesisadused uuritud silodes olid vastavalt 1,3;
1,4 ja 1,0 g/kg kuivaines (KA). Statistiliseks analüüsiks valiti proovid, kus propanoolisisaldus
oli ≥ 0,5 g/kg KA. Silod jagati grupideks järgmiste tunnuste järgi: silotüüp, kuivainesisaldus,
niide, hoidla tüüp ja silokindlustuslisandi kasutamine. Gruppides leiti keskmised
propanoolisisaldused ja võrreldi omavahel konkreetse tunnusega seose leidmiseks. Madalama
kuivainesisaldusega silodes oli propanoolisisaldus oluliselt suurem (p < 0,01). Statistiliseks
analüüsiks valitud proovidega viidi läbi korrelatsioonanalüüsi fermentatsiooninäitajate vahel
ning ka eraldi propanoolisisalduse ja fermentatsiooninäitajate vahel mainitud gruppides. Seos
leiti propanooli, äädikhappe ja prorioonhappe vahel. Äädikhappe korrelatsioonikordaja nii
propanooliga kui ka propioonhappega oli r = 0,64 ning propanooli ja propioonhappe vahel r =
0,49. Esimese niite puhul oli propanooli ja sekundaarsete fermentatsiooniproduktide vaheline
seos tugevam kui teise ja kolmanda niite puhul. Silokindlustuslisandi mõju
propanoolisisaldusele selle töö raames ei leitud. Uurimistöö raames selget seost
propanoolisisalduse ja sekundaarste fermentatsiooninäitajate vahel ei leitud. Kõikide
siloproovide keskmine propanoolisisaldus oli võrreldav propioonhappe ja
propüleenglükoolisisaldusega, seega propanooli määramine tuleks võtta kasutusele silo
fermentatsiooninäitajana.
Propionate is an important compound in metabolism in ruminants, and one should consider all sources of propionate when preparing rations. It is necessary to consider the amount of propionate that animals obtain from silage, which is the main feed for dairy cattle in Estonia. Propanol is a precursor for propionate, but it is not measured routinely. The aim of this study was to evaluate propanol contents in grass and maize silages, and to examine relationships between propanol and other silage fermentation parameters. In this study, 1,678 silage samples were analysed over a one year period. Propanol and isopropanol were measured in addition to other routine fermentation parameters. Mean concentrations of propanol, propylene glycol and propionic acid were 1.3; 1.4 and 1.0 g/kg in dry matter (DM) respectively. For statistical analysis only samples with propanol concentrations of more than 0.5 g/kg DM were selected. These samples were divided into groups according to their characteristics: silage type dry matter content, silage cut, storage type and silage additive used. Mean concentrations of propanol were measured and compared within the groups to examine the relationship of each characteristic to the propanol content. Statistically significant differences in the propanol contents were found in the group with different silage DM (p < 0.01). Correlation analyses between the fermentation parameters, and also separately between propanol and other fermentation parameters within the groups, were performed. The correlation coefficient of acetic acid with both propanol and propionic acid was r = 0.64, while between propanol and propionic acid this was r = 0.49. Correlation analyses showed a higher correlation coefficient between propanol contents and secondary fermentation products for the first cut. No impact of the type of additive used on the propanol content was observed in this study. No clear relationships between propanol and secondary fermentation parameters were found. The mean propanol contents in all silages were related to contents of propionic acid and propylene glycol. The propanol content should be considered a fermentation parameter of silage.
Propionate is an important compound in metabolism in ruminants, and one should consider all sources of propionate when preparing rations. It is necessary to consider the amount of propionate that animals obtain from silage, which is the main feed for dairy cattle in Estonia. Propanol is a precursor for propionate, but it is not measured routinely. The aim of this study was to evaluate propanol contents in grass and maize silages, and to examine relationships between propanol and other silage fermentation parameters. In this study, 1,678 silage samples were analysed over a one year period. Propanol and isopropanol were measured in addition to other routine fermentation parameters. Mean concentrations of propanol, propylene glycol and propionic acid were 1.3; 1.4 and 1.0 g/kg in dry matter (DM) respectively. For statistical analysis only samples with propanol concentrations of more than 0.5 g/kg DM were selected. These samples were divided into groups according to their characteristics: silage type dry matter content, silage cut, storage type and silage additive used. Mean concentrations of propanol were measured and compared within the groups to examine the relationship of each characteristic to the propanol content. Statistically significant differences in the propanol contents were found in the group with different silage DM (p < 0.01). Correlation analyses between the fermentation parameters, and also separately between propanol and other fermentation parameters within the groups, were performed. The correlation coefficient of acetic acid with both propanol and propionic acid was r = 0.64, while between propanol and propionic acid this was r = 0.49. Correlation analyses showed a higher correlation coefficient between propanol contents and secondary fermentation products for the first cut. No impact of the type of additive used on the propanol content was observed in this study. No clear relationships between propanol and secondary fermentation parameters were found. The mean propanol contents in all silages were related to contents of propionic acid and propylene glycol. The propanol content should be considered a fermentation parameter of silage.
Kirjeldus
Märksõnad
silo, propanool, fermentatsioon, magistritööd