- 學位論文
環境溫度、飼糧中能量含量及風速對肉雞生長成績、體溫及屠體性狀之影響
Effects of environmental temperatures, dietary energy levels and wind velocity on growth performance, body temperature and carcass characteristics in broiler
摘要
本研究之目的為瞭解在不同環境溫度下吹風，並且透過餵飼不同能量飼糧及不同風速對肉雞生長成績、體溫變化、屠體性狀與組成之影響。試驗一使用1日齡經過公母鑑別的母艾維因品系肉雞，第一週全部雞隻飼養於30℃，中、低溫組每週降溫至第四週，高溫組環境溫度維持30℃，中溫組環境溫度降至22℃，低溫組降至14℃；第四週開始加入風速，風速平均維持在0.9 s/m，試驗為期8週。試驗二為3×2×2之複因子設計，實驗雞隻、溫度和風速同試驗一；三種不同溫度下分別餵飼高能量飼糧（添加3%油脂）及低能量飼糧（添加3%粗糠粉），有吹風及無吹風兩種因子，試驗為期8週。試驗三為3×3複因子設計，使用4週齡母艾維因品系肉雞，試驗溫度分別為32℃、28℃及22℃，在三種溫度下分別在給予無吹風、0.6 m/s及1.0 m/s三種風速，試驗期為期3週。資料蒐集包含每週攝食量、體重、體增重、飼料效率和體溫；飼養期後進行屠宰，並計算屠體性狀；屠體採樣後進行水分、灰分及礦物質分析。 試驗一結果顯示，生長成績方面，22℃及14℃下給予吹風，有較佳之攝食量和體增重，30℃則飼料效率較佳。體溫方面，第四週開始吹風後，腳脛溫有劇烈下降之趨勢；而當環境溫度逐漸下降時，體溫（直腸溫、腋溫及腳脛溫）有逐漸下降之趨勢。在屠體性狀方面，在低溫條件下其胸肉、翅膀、內臟之比例有較高之趨勢；而在高溫其腿肉及腹脂比例有較高之趨勢。屠體成分方面，在低溫下胸肉及腿肉中水分及磷含量有較高之趨勢，而鐵、鋅、銅、錳、鈣、鎂和鉀則有較低之趨勢。 試驗二結果顯示，環境溫度方面與實驗一有相同之趨勢。餵飼低能量飼糧，雖然有較高之攝食量，增重及飼料效率皆有較差之趨勢；有吹風的情形下，其增重明顯的較重，但飼料效率有較差之趨勢。體溫方面，無論餵飼高低能量飼糧或有無吹風的情形下，體溫無明顯之差異。在屠體性狀方面，餵飼高能量飼糧對於腿肉、腹脂及大腿肉皆有較高之比例；給予吹風，對於肉雞血液、心臟、肝臟及腹脂之比例皆有較高之趨勢。屠體成分方面，餵飼不同能量飼料，對肉雞腿肉礦物質之影響，並無顯著之差異性，餵飼低能量飼糧下，胸肉則有較高的灰分及鈣含量；有吹風的情形下，肉雞腿肉水分及鐵含量有較高趨勢；在胸肉方面，吹風會有較高的水分含量，但其灰分、礦物質含量並無顯著之差異性。 試驗三結果顯示，肉雞在不同環境溫度下之生長成績與試驗一、二皆有相同之趨勢，但是飲水量在32℃下顯著有較低之趨勢；給予1.0 m/s風速下有較高之攝食量、體增重及飲水量。體溫方面，增加風速時，會降低腳脛及雞冠溫度。屠體性狀方面，給予1.0 m/s風速，對於肉雞血液、心臟、肝臟及腹脂之比例皆有較高之趨勢；在肌肉產量方面，高風速下有較高的胸肉產量；而腿肉及腿肉比例則較低。屠體成分方面，在32℃及28℃下，腿肉與胸肉有較低的水分含量；腿肉中的灰分、磷、鎂、鉀及鈣含量皆有較高之趨勢。 綜合上述試驗結果可知，在飼養其溫度與吹風會顯著的影響肉雞的生長成績、體溫變化及屠體性狀。而在高環境溫度下，餵飼高能量飼糧可改進肉雞的生長成績，若是配合適度通風，可有效的改善肉雞熱緊迫。
並列摘要
The objective of the study was to determine the different ambient temperature, ventilation, and feeding of different energy diets and different wind speeds on the growth performance, body temperature, carcass traits and composition of broilers. Experiment 1, twenty seven was used 1-day old female broilers were randomly allocated into 3 treatment groups. Treatment 1: low temperature group; Treatment 2: thermoneutral group; Treatment 3: high temperature group. On the forth week, Treatment 3 was maintained at 30℃, it was reduced to 22℃ in Treatment 2 and 14℃ in Treatment 1. Commencing on the 4th week, the wind velocity was maintained at 0.9 m/s. The experiment lasted for 8 weeks. Experiment 2 was 3×2×2 factorial design, experimental chickens, temperature design, and wind speed with same the first experiment; were fed a high-energy diet at three different temperatures （supplement 3% seed fat） and low- energy diets (supplement 3% rice hull powder), there were two factors of wind and without wind. The experiment lasted for 8 weeks. Experiment 3, fifty-five 4 weeks old female broiler were randomly allocated to 3×3factorial arrangement with three wind velocity (no wind velocity, 0.6 m/s wind velocity, and 1.0 m/s wind velocity) and three temperatures (22℃, 28℃, and 32℃). The experiment lasted for 3 weeks. During experiment data collection included feed intake, body weight gain, feed efficiency, body temperature; Experimental selection of similar weight four chickens slaughtered and calculated percentage of carcass; carcass sampling, moisture, ash and mineral analysis. Experiment 1 the results of indicated that, low temperature an thermoneutral group had higher feed intake and body weight gain. The feed efficiency of the high temperature group was better. In body temperature, the fourth week to give wind for shank temperature was decreased. When the ambient temperature decreased was gradually declining trend in body temperature (rectum temperature, axillary temperature and shank temperature). In carcass traits, low temperature was higher breast meat, wings, and visceral proportion, while high temperatures group was higher proportion of abdominal fat, thigh meat, and drumstick meat. Carcasses analysis, at low temperature was higher moisture and phosphorus content in the breast and thigh meat. Experiment 2 the results of showed the effect of different environment temperature on broiler common trend with experiment 1. Fed low energy diets was higher feed intake, whereas body weight gain and feed efficiency were decreased trend. Given velocity under body weight gain significantly increased, but have poor feed efficiency. In body temperature, regardless of the high and low energy diets fed or ventilation, body temperature no apparent difference. In carcass traits, feeding high energy diets for thigh meat, drumstick meat, and abdominal fat was higher proportion. Given ventilation of heart, liver and abdominal fat in broilers there is high percentage. Carcass composition, feed different energy diets is higher ash and calcium content in breast meat; ventilation to broiler thigh and breast meat has high moisture, whereas ash and mineral content is no significantly affected. Experiment 3 the results of showed that growth performance of broiler chickens at different environmental temperatures and test one or two has the same trends, but water quantity trends have significantly lower under 32℃; the wind speed at 1.0 m/s has higher feed intake, body weight gain, and water intake. Increased wind speeds was gradually declining trend in body temperature (rectum temperature, axillary temperature, comb temperature, and shank temperature). In carcass traits, 1.0 m/s wind speed are high percentage trends in blood, heart, liver and abdominal fat of broilers; was higher breast meat percentage in high wind speed and thigh meat, but drumstick leg meat is low. In carcass composition, under 32℃and 28℃, thigh and breast meat was a lower moisture content; thigh meat has higher trend ash, phosphorus, magnesium, potassium and calcium. The above experiment results, raising temperature and briefings significantly affects broiler growth performance, temperature change and carcass traits. At high ambient temperatures, feeding of high energy diets can improve the growth performance of broiler, if combined with proper ventilation, which can effectively improve the broilers hot stress.