循环高温对蛋鸡消化机能的影响及营养调控技术研究

发布时间：2018-06-22 09:10

本文选题：循环高温 + 蛋鸡　；参考：《东北农业大学》2017年硕士论文

【摘要】：环境高温是影响家禽生产的一个重要因素,高温环境下家禽采食量降低,肉鸡生长速度减慢,蛋鸡产蛋率、蛋重及体重下降。环境高温影响家禽生产性能并非全部由于采食量下降引起的,即使在相同采食量的条件下,环境高温仍显著降低家禽的生产性能,这可能与降低营养物质利用有关。目前我国蛋鸡生产中,除少量鸡舍采用自然通风或机械通风降温外(该类鸡舍夏季舍内温度一般在29~35℃之间波动),大部分规模化蛋鸡舍均安装了风机-湿帘等降温系统,夏季鸡舍内温度一般可以控制在30℃以下,导致大多数生产及研究人员忽视夏季高温对蛋鸡的影响。这种27~30℃循环温度是否会影响蛋鸡生产性能、蛋品质及消化机能目前尚不清楚。针对这一问题,本论文开展以下两个试验,通过模拟夏季循环高温,研究不同循环高温对蛋鸡采食量、营养物质消化率、消化酶活性及基因表达等方面的影响;同时研究循环高温下改变蛋鸡日粮的营养水平,是否可以缓解环境高温的不利影响。试验一:选取28周龄高产海兰褐蛋鸡288只,随机分为21℃适温组、27~30℃循环高温组、29~35℃循环高温组和21℃采食配对组(按前1天29~35℃组的采食量饲喂),每个处理组6个重复,每个重复12只鸡,分别饲养于4个人工环境控制舱内,试验持续4周,研究不同循环高温对蛋鸡生产性能、蛋品质、消化机能以及抗氧化能力、免疫能力的影响。试验二:选择38周龄连续产蛋的海兰褐蛋鸡288只,随机分为I低能组(ME2700 kcal/kg,CP16%)、II中能组(ME2800 kcal/kg,CP16%)、III高能组(ME2900 kcal/kg,CP16%)和IV高蛋白组(ME2700 kcal/kg,CP18%)四个处理组,每个处理组6个重复,每个重复12只鸡(每个重复4个蛋鸡笼),试验持续4周,饲养于人工环境控制舱内,仓内温度设定为27~30℃循环高温(温度变化模式同实验一),研究循环高温环境下不同日粮能量和蛋白水平对蛋鸡生产性能、蛋品质的影响。结果:1、与适温组相比,27~30℃组蛋鸡采食量、体重和蛋重显著降低(P0.05),蛋壳强度显著降低(P0.05),除蛋黄颜色显著降低(P0.05)外,不影响鸡蛋品质其他相关指标(P0.1);而29~35℃组蛋鸡采食量、体重、蛋重和产蛋率均显著降低(P0.05),蛋壳厚度和蛋壳强度显著降低(P0.05),破蛋率显著升高(P0.05),鸡蛋蛋白高度和蛋黄颜色均显著降低(P0.05)。与采食配对组相比(采食量相同条件下),29~35℃组蛋重显著降低(P0.05),料蛋比提高(P0.05),蛋壳强度显著降低(P0.05),鸡蛋品质差异不显著(P0.1)。2、与适温组相比,27~30℃组蛋鸡体核温度(TC)无显著差异,除血清T-AOC降低外,肝脏和血清中MDA含量及抗氧化酶活性均无显著差异,血清Ig A、Ig M含量显著降低(P0.05);而29~35℃组蛋鸡TC显著升高(P0.05),血清和肝脏中MDA含量显著升高(P0.05),T-AOC显著下降(P0.05),血清GSH-Px活性有降低趋势(P0.1),血清IgA、Ig M含量以及脾脏指数显著降低(P0.05)。与采食配对组相比(采食量相同条件下)血清和肝脏中MDA含量同样显著升高(P0.05),T-AOC显著下降(P0.05),血清GSH-Px活性显著降低(P0.05),血清中仅IgA含量显著降低(P0.05),Ig M、Ig G含量以及脾脏指数无显著差异。3、与适温组相比,27~30℃组蛋鸡饲料中干物质、蛋白、脂肪、钙、磷、能量消化率无显著差异(P0.1),除回肠和空肠淀粉酶活性显著降低外,其他肠段(十二指肠、空肠、回肠)中淀粉酶、脂肪酶、糜蛋白酶和胰蛋白酶活性无显著差异(P0.1);胰腺各消化酶活性及消化酶m RNA表达水平均差异不显著(P0.1),另外蛋鸡空肠的隐窝深度显著升高(P0.05),绒毛高度和隐窝深度比有降低趋势(P0.1),而十二指肠及回肠的绒毛高度、隐窝深度及其比值无显著差异(P0.1);与适温组相比,29~35℃组蛋鸡蛋白质代谢率有降低趋势(P0.1),其他营养物质消化率无显著差异(P0.1),回肠淀粉酶活性显著降低(P0.05),空肠淀粉酶具有下降的趋势(P0.1);其他各肠道淀粉酶、脂肪酶、糜蛋白酶和胰蛋白酶活性与对照组无显著差异(P0.1);胰腺中胰蛋白酶活性有降低趋势(P0.1),淀粉酶、脂肪酶、糜蛋白酶活性差异不显著(P0.1),但胰腺各消化酶mRNA相对表达量无显著差异(P0.1),另外蛋鸡空肠隐窝深度显著升高(P0.05),绒毛高度和隐窝深度比值有降低趋势(P0.1)。与采食配对组相比(采食量相同条件下),29~35℃组蛋鸡饲料蛋白质代谢率有降低趋势(P0.1)。在相同采食量条件下,29~35℃显著降低蛋鸡脂肪、蛋白代谢率显著降低(P0.05),干物质代谢率和AME值有降低趋势(P0.1);29~35℃组回肠淀粉酶活性显著降低(P0.05),空肠胰蛋白酶活性显著降低(P0.05),空肠淀粉酶活性有下降趋势(P0.1);胰腺中糜蛋白酶差异不显著(P0.1),淀粉酶和胰蛋白酶活性显著降低(P0.05),脂肪酶活性有降低趋势(P0.1),各种消化酶mRNA相对表达量无显著差异(P0.1)。另外与采食配对组相比,蛋鸡各肠道绒毛高度、隐窝深度及其比值无显著差异(P0.1)。4、提高日粮能量水平,采食量有降低趋势(P0.1),其中中能和高能组蛋鸡采食量显著低于低能组;提高日粮能量水平,产蛋率和蛋重略有提高(5.5%,0.8%),未到达显著水平,但料蛋比显著降低。提高日粮蛋白水平,采食量显著降低(P0.05),产蛋率和蛋重略有提高(3.3%,1.2%),未达到显著水平,但料蛋比显著降低(P0.05)。提高日粮能量和蛋白水平对蛋壳和鸡蛋品质无显著影响(P0.1)。结论:夏季鸡舍温度即使在27~30℃之间波动仍显著影响蛋鸡生产性能。高温对蛋鸡产蛋性能、蛋品质的影响与采食量下降有关,高温直接影响蛋壳的形成。高温对蛋鸡抗氧化能力的影响与体温升高有关,对免疫机能的影响与降低采食量有关。高温对蛋鸡生产性能的影响不仅与采食量降低有关,还直接影响蛋鸡的消化机能。提高日粮能量和蛋白水平,能量和蛋白摄入量增加,产蛋率及蛋重增加但未达到显著水平,饲粮利用效率显著提高。
[Abstract]:Environmental temperature is an important factor affecting the production of poultry. Under the high temperature environment, the feed intake of poultry is reduced, the growth rate of broilers is slow, laying rate of laying hens, egg weight and weight decrease. The environmental temperature affects the performance of poultry not all due to the decrease of feed intake. Even under the same feed intake, the environmental temperature is still significantly reduced. The production performance of poultry may be related to reducing the utilization of nutrients. In the production of egg chickens in our country, in addition to a small number of chicken houses with natural ventilation or mechanical ventilation (the temperature fluctuates between 29~35 C in summer houses in this kind of chicken house), most of the large egg laying hens are equipped with a cooling system such as the fan - wet curtain and so on, and the temperature of the chicken house in summer. It is generally controlled below 30 degrees, causing most production and researchers to ignore the effect of summer high temperature on laying hens. Whether the temperature of 27~30 centigrade can affect the performance of laying hens, egg quality and digestive function is not yet clear. In this paper, the next two experiments are carried out in this paper to simulate the high temperature in the summer cycle. The effects of different cycles of high temperature on feed intake, nutrient digestibility, digestive enzyme activity and gene expression, and whether to change the nutritional level of laying hens under cyclic high temperature, and whether the adverse effects of environmental temperature were alleviated. Experiment 1: 28 Zhou Linggao Brown laying hens were selected to be randomly divided into 21 degrees centigrade temperature group, 27 ~30 centigrade cycle high temperature group, 29~35 centigrade high temperature group and 21 centigrade feeding pair group (feed intake at 29~35 C for the first 1 days), each treatment group was 6 repetitions, each repeated 12 chickens, respectively reared in 4 artificial environment control tanks, the experiment lasted for 4 weeks, and studied the production performance, egg quality, digestive function and oxygen resistance of different cycle high temperature. Test two: 288 of the 38 week old egg laying hens were randomly divided into I low energy group (ME2700 kcal/kg, CP16%), ME2800 kcal/kg (CP16%), III high energy group (ME2900 kcal/kg, CP16%), and high protein group four treatment groups, each treatment group was 6 repeat, each repetition 12 chickens (each repeat 4 egg cages), the experiment lasted for 4 weeks and kept in the artificial environment control cabin. The temperature of the silo was set at 27~30 centigrade temperature (temperature change mode and Experiment 1). The effects of different dietary energy and protein levels on the productive energy and egg quality of laying hens under cyclic high temperature environment were studied. Results: 1, compared with the temperature group, 27~30 C The feed intake, weight and egg weight decreased significantly (P0.05), and the egg shell strength decreased significantly (P0.05), except for the significant decrease of egg yolk color (P0.05), which did not affect the other related index of egg quality (P0.1), while the feed intake, weight, egg weight and egg production rate of layers in 29~35 group were significantly decreased (P0.05), the thickness of eggshell and eggshell strength decreased significantly (P0.05). The egg yolk height and egg yolk color were significantly decreased (P0.05). The egg weight of 29~35 centigrade was significantly reduced (P0.05), the ratio of egg to egg (P0.05), egg shell strength decreased (P0.05), egg quality was not significant (P0.1).2, compared with the temperature group at 29~35. There was no significant difference in the body nucleus temperature (TC). Except for the decrease of serum T-AOC, there was no significant difference in the content of MDA and antioxidant enzymes in the liver and serum, and the content of serum Ig A and Ig M decreased significantly (P0.05), while TC significantly increased (P0.05) in the 29~35 centigrade group, and the MDA content in the serum and liver was significantly increased. The level of serum IgA, Ig M and spleen index decreased significantly (P0.05). The content of MDA in serum and liver was also significantly increased (P0.05), T-AOC decreased significantly (P0.05), GSH-Px activity decreased significantly (P0.05) and the content of only IgA in serum decreased significantly (P0.05) compared with the feeding pair group (P0.05). There was no significant difference in the spleen index (.3). There was no significant difference in the dry matter, protein, fat, calcium, phosphorus and energy digestibility (P0.1) in the 27~30 C group, and the activity of amylase, lipase, chymotrypsin and trypsin in other intestinal segments (duodenum, empty intestines and ileum) was not significantly different from that in the suitable temperature group (P0.1). Significant difference (P0.1); the activity of digestive enzymes and the expression of digestive enzyme m RNA were not significantly different (P0.1), and the depth of the crypts in the jejunum increased significantly (P0.05), the height of the villi and the depth of the recess decreased (P0.1), but there was no significant difference between the villous height of the duodenum and the ileum, the depth of the recess and its ratio (P0.1). Compared with the group, the protein metabolism rate in the 29~35 group was reduced (P0.1), the other nutrient digestibility had no significant difference (P0.1), the intestinal amylase activity decreased significantly (P0.05), the jejunum amylase had a downward trend (P0.1), and there was no significant difference between the other intestinal amylase, lipase, chymotrypsin and trypsin (P0.). 1) the trypsin activity in the pancreas decreased (P0.1), the amylase, lipase and chymotrypsin were not significantly different (P0.1), but the relative expression of mRNA in the digestive enzymes of the pancreas was not significantly different (P0.1), and the depth of the jejunum recess increased significantly (P0.05), and the ratio of the villus height to the recess depth was decreased (P0.1). Under the same feeding condition, the protein metabolism rate of the feed chicken in 29~35 C was reduced (P0.1). At the same feed intake, the fat of the egg chicken, the protein metabolism rate decreased significantly (P0.05), the metabolic rate of dry matter and the AME value decreased (P0.1) at the same feed intake, and the activity of the ileum amylase in 29~35 centigrade group decreased significantly (P0.05) and jejunum (P0.1). The activity of trypsin decreased significantly (P0.05), the activity of jejunum amylase decreased (P0.1), the differences of chymotrypsin in the pancreas were not significant (P0.1), the activity of amylase and trypsin decreased significantly (P0.05), the activity of lipase was decreased (P0.1), and the relative expression of various digestive enzyme mRNA was not significantly different (P0.1). In addition, compared with the feeding pairing group, the activity of amylase and trypsin decreased significantly (P0.1). The height of the intestinal villi, the depth of the recess and its ratio were not significantly different (P0.1).4, and the diet energy level was improved (P0.1), and the feed intake of the middle energy and high energy groups was significantly lower than that of the low energy group; the dietary energy level, the egg production rate and the egg weight were slightly increased (5.5%, 0.8%), and the egg weight was not significant, but the egg ratio was significantly higher than that of the eggs. Decrease. Increase dietary protein level, feed intake significantly decreased (P0.05), egg laying rate and egg weight slightly increased (3.3%, 1.2%), not significant level, but the egg ratio significantly decreased (P0.05). Increasing dietary energy and protein level had no significant effect on egg shell and egg quality (P0.1). Conclusion: the temperature of chicken house in summer is still fluctuating even between 27~30 and temperature. The effect of high temperature on laying performance of egg laying hens, the effect of egg quality on egg quality is related to the decline of feed intake. High temperature affects the formation of eggshell directly. The effect of high temperature on the antioxidant capacity of layers is related to the increase of body temperature. The influence on the immune function is related to the reduction of feed intake. The effect of high temperature on the performance of laying hens is not only with the feed intake. It also directly affected the digestive function of the laying hens, increased the energy and protein level of the diet, increased the energy and protein intake, increased the egg production rate and egg weight, but did not reach a significant level, and the utilization efficiency of the diet increased significantly.
【学位授予单位】：东北农业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S831

【参考文献】