Monensiini ja toitumuse mõju piimalehmade ainevahetusele ja toodangule
Laen...
Kuupäev
2018
Kättesaadav alates
Autorid
Ajakirja pealkiri
Ajakirja ISSN
Köite pealkiri
Kirjastaja
Eesti Maaülikool
Abstrakt
Piimatoodangu kasvuga on lehmadel suurenenud terviseprobleemid ning karjast
väljalangevus. Loomakasvataja jaoks on ülioluliseks saanud lehma üleminekuperiood,
sest lehma tervislikust seisust sel perioodil sõltub kogu laktatsiooni toodang ning tema
karjas püsimine. Piimalehmade ainevahetuse parandamiseks manustatakse farmides
nendele vatsa propioonhappe sünteesi suurendavat monensiini. Magistritöös püstitati
hüpotees, mille kohaselt vähendab monensiini manustamine keharasvade kasutamist ja
ketoosi haigestumise riski ning suurendab piimatoodangut. Ühtlasi uuriti poegimisaegse
toitumuse mõju kehavarude kasutamise intensiivsusele. Katsesse võeti 30
korduvpoeginud looma, neist 15-le manustati 2017. aasta suvel 3 nädalat enne poegimist
monensiini. Kuue nädalase katseperioodi jooksul võeti lehmadelt vereproove ning hinnati
nende toitumust. Vereproovidest määrati esterifitseerimata rasvhapete (NEFA) ja β-
hüdroksübutüraadi (BHB) sisaldus ning aspartaadi aminotransferaasi (AST) aktiivsus.
Lisaks monensiini mõjule vaadati, kuidas mõjutab toitumus üleminekuperioodil vere
metaboliitide dünaamikat ja piimatoodangut. Monensiinil oli kogu katseperioodi vältel
mõju NEFA sisaldusele (P<0,05), kuid mõju BHB sisaldusele ja AST aktiivsusele puudus.
Toitumuse mõju oli sarnane nagu monensiinil, BHB-le ja AST-le mõju puudus, kuid
NEFA sisaldus oli optimaalses toitumuses lehmadel madalam (P<0,05), kui ülemäärases
toitumuses lehmadel. Piimatoodangut monensiini manustamine ja toitumus ei mõjutanud.
Magistritöö tulemusena selgus, et monensiin vähendas kehavarude kasutamise
intensiivsust, kuid ei vähendanud ketoosi haigestumise riski. Monensiini manustamise
majandusliku efektiivsuse selgitamine vajab täiendavaid uurimusi.
With the growth of milk production in dairy cows, frequency of health problems and culling rates have also risen. Management of transition cows is a challenge for farmers due to large physiological changes in dairy cows during that period. Cows health in transition period impacts the whole lactation and its staying in the herd. To improve dairy cow metabolism, on some farms monensin, that increases propionate synthesis in rumen, is administered. The hypothesis of this study was that prepartum monensin administration to dairy cows decreases intensity of fat mobilization and ketosis risk and increases milk production. Impact of parturition body condition on the intensity of body reserve use was also observed. Three weeks before parturition monensin was administered to 15 of 30 multiparous cows. During the six-week study blood samples were taken and body condition score (BCS) was evaluated. Blood non-esterified fatty acids (NEFA) and β- hydroxybutyrate (BHB) concentration, and aspartate aminotransferase (AST) activity was determined. The impact of monensin administration and cows body condition on NEFA, BHB, AST and milk production were evaluated. Monensin decreased blood NEFA concentration (P<0.05) over the study period but had no impact on BHB and AST. Results were similar for body condition. Cows with optimal BCS had lower blood NEFA concentration (P<0.05) than over conditioned cows, but no influence on BHB level and AST activity was found. Monensin and body condition did not influence milk production. The results of the study ascertained positive effect of monensin on reducing intensity of fat mobilization but not on ketosis risk. To evaluate financial effectiveness of monensin administration additional studies are needed.
With the growth of milk production in dairy cows, frequency of health problems and culling rates have also risen. Management of transition cows is a challenge for farmers due to large physiological changes in dairy cows during that period. Cows health in transition period impacts the whole lactation and its staying in the herd. To improve dairy cow metabolism, on some farms monensin, that increases propionate synthesis in rumen, is administered. The hypothesis of this study was that prepartum monensin administration to dairy cows decreases intensity of fat mobilization and ketosis risk and increases milk production. Impact of parturition body condition on the intensity of body reserve use was also observed. Three weeks before parturition monensin was administered to 15 of 30 multiparous cows. During the six-week study blood samples were taken and body condition score (BCS) was evaluated. Blood non-esterified fatty acids (NEFA) and β- hydroxybutyrate (BHB) concentration, and aspartate aminotransferase (AST) activity was determined. The impact of monensin administration and cows body condition on NEFA, BHB, AST and milk production were evaluated. Monensin decreased blood NEFA concentration (P<0.05) over the study period but had no impact on BHB and AST. Results were similar for body condition. Cows with optimal BCS had lower blood NEFA concentration (P<0.05) than over conditioned cows, but no influence on BHB level and AST activity was found. Monensin and body condition did not influence milk production. The results of the study ascertained positive effect of monensin on reducing intensity of fat mobilization but not on ketosis risk. To evaluate financial effectiveness of monensin administration additional studies are needed.
Kirjeldus
Magistritöö
Loomakasvatuse õppekaval
Märksõnad
magistritööd, ketoos, piimalehmad, ainevahetus