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本試驗的主要目的在于研究藍耳病病毒感染和免疫接種對豬生長性能、日糧利用率、糞污產量、以及糞污池CO2, CH4, H2S, N2O和NH3排放的影響。試驗選用48頭21日齡斷奶仔豬，隨機分為4組，試驗處理為2（藍耳病攻毒與否）×2（藍耳病免疫接種與否）雙因素設計。記錄體重、采食量、糞污產量，50-78日齡以及試驗結束后24天內每天記錄糞污產氣量。不論是否免疫接種，藍耳病病毒感染都能顯著降低末重、日增重、采食量（P＜0.01），以及酸性洗滌纖維（ADF，P=0.05）和粗脂肪（P=0.02）的利用率。試驗處理對糞污產量、糞污pH值、木質素利用率和氮沉積無顯著影響。藍耳病感染的豬只其糞污CO2排放量顯著增加（P=0.01）。免疫接種和病毒感染對糞污N2O產量有互作作用：無論是否被病毒感染，免疫接種的豬只糞污N2O產量沒有顯著區別，而病毒感染卻對未免疫接種的豬只糞污N2O產量（氣體產量/頭豬）有影響。同樣試驗處理對H2S和N2O（氣體產量/kg揮發性固體糞污產量）有互作影響（分別為P=0.01和0.0001），與上一結果（每頭豬N2O產量）相似：免疫接種豬只不論是否感染其氣體排放率無顯著差異。藍耳病病毒感染提高了氮排放（N2O形式）/kg糞污總氮（P=0.03）。總之，試驗結果表明藍耳病病毒感染可以降低生長速度和營養物質利用率，同時增加糞污氣體排放量。

The objectivesof this study were to examine the effects of porcine reproductive andrespiratory syndrome virus (PRRSV) infection and vaccination on pig growth,dietary nutrient efficiency of utilization, manure output, and emissions ofCO2, CH4, H2S, N2O, and NH3 gases from stored manure. Forty-eight pigs, aged 21d at the start of the study, were subjected to 1 of 4 treatment combinationsarranged in a 2 × 2 factorial design with main factors of PRRSV vaccination andPRRSV infection. Body weight, ADFI, manure output, and nutrient efficiency ofutilization were assessed and gas emissions from stored manure were determineddaily from 50 to 78 d of age and for 24 d after completion of the animal phase.Infection with PRRSV markedly reduced final BW, ADG, and ADFI (P < 0.01) andreduced efficiencies of ADF and ether extract utilization (P = 0.05 and P =0.02, respectively) regardless of vaccination status. No significant treatmenteffects were found on manure output, manure pH, efficiencies of ligninutilization, and N retention. Infecting pigs with PRRSV increased daily manureCO2 emission per pig (P = 0.01). There was an interaction between immunizationand infection for N2O per pig with manure from uninfected, vaccinated pigsproducing as much as the manure from infected, vaccinated pigs whereas therewas a difference by PRRSV infection state for nonvaccinated pigs. There werealso interactions between treatments for H2S and N2O emissions per kilogram ofmanure volatile solids excreted (P = 0.01 and P = 0.0001, respectively) withthe same pattern as for N2O per pig; that is, the vaccinated pigs had similarrates of emission regardless of infection state. Pigs infected with PRRSVincreased N2O nitrogen per kilogram of total N excreted compared withnoninfected groups (P = 0.03). Collectively, these results indicated that PRRSVinfection caused decreased growth rates and nutrient utilization efficiency andincreased gas emissions from stored manure。

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