母猪在哺乳期的最佳状态
发布单位:新萄京网址查看次数:8116
时间:2019-09-25
Kyler R Gilbreath,Gayan I Nawaratna,Tryon A Wickersham,M Carey Satterfield,Fuller W Bazer,Guoyao Wu
翻译&校对:上海亘泰实业集团
近年来,基因、营养和健康状况的改善推动了母猪生产性能的提高。为了满足母猪日益增加的需求,在一系列的营养解决方案中,仍有一些营养物质未得到充分利用,碳水化物酶类就是其中之一。养猪户需要母猪来饲养健康、生长迅速的小猪。在哺乳期,母猪的能量需求急剧增加。然而,在分娩后的最初几天,饲料摄入量是有限的。在这些重要的代谢变化期间,身体储备的调动是必要的。母猪最大的挑战是在不损失太多体内蛋白质储备的情况下恢复生产,母猪产奶性能对仔猪的健康成长起着至关重要的作用。从经济角度看,断奶时窝仔数和窝仔重是母猪未来生产性能的一个指标。如果母猪在仔猪断奶时身体状况不佳,它们将需要更长的时间才能恢复生产。因此,需要进一步优化饲料摄入量和营养物质利用。
在泌乳母猪日粮中添加碳水化合物酶复合物可以提高泌乳期间蛋白质和能量的消化率。由于哺乳母猪的饲料摄入量是一个问题,在现有配方的基础上添加酶,以最大限度地从日粮中释放营养。然而,直到现在,关于这方面的科学研究相对较少。因此,大家进行了多项科学研究,以评估特定的碳水化合物酶复合物在不同条件下对泌乳母猪机体状况、营养物质消化率和仔猪性能的影响。
研究包括八个试验,采用meta方法进行综合分析。根据胎次将母猪分为三组:组1为初产母猪、组2为二三胎母猪、组3为4胎及以上母猪。
研究显示,1)在泌乳期间所有母猪体重平均减轻21kg,与组2比较,组1和组3母猪体重损失明显减少。碳水化合物酶复合物的添加降低了所有胎次组的母猪体重损失(见图1),平均每头猪降低了3kg的体重损失,相当于其体重的1-2%。饲喂初产母猪碳水化合物酶后,其机体储备比例损失明显降低。这些变化可以用更好的饲料消化率来说明。
图1. 碳水化合物酶复合物降低了所有胎次组母猪的体重下降
2)在高、低密度日粮中,碳水化合物酶复合物的添加均可提高干物质、有机质和能量消化率。这意味着母猪能够从食物中获得更多的营养。在4种日粮处理组之间,干物质摄入量的统计是相同的,故这些影响与干物质的摄入量无关。然而,饲料和能量的摄入量随胎次的增加而升高了。与多胎母猪相比,饲喂对照饲料的初产母猪能量摄入量较低,体重减轻较多。净能量摄入、体重变化与窝增重之间存在明显的相关性。
3)在饲喂母猪碳水化合物酶的结果中,更高的净能摄入量是与体重损失进行评估和比较的。取决于母猪的胎次和机体状况,在生长和产奶性能之间,能量的分配是不同的。研究表明,增加初产母猪的净能摄入量主要是为了改善它们的身体状况,而不是为了产奶,出现这一现象,与初产母猪发育不完全有关;这样将有助于其降低体重损失,保护它们的长久性能。在多胎母猪方面,由于其更高的背膘厚度,更重要的是其产奶性能的优化和仔猪健康的提高。
4)仔猪窝增重受采食量的影响,特别是在初产母猪组(由于其对生长和身体储备的需求更高)。添加碳水化合物酶增加了断奶时仔猪的窝增重(见图2),这个影响在多胎母猪组更明显,这可能是因为机体重量和窝增重的不同,或者是营养分配的差异。断奶时仔猪的体重是衡量其未来生长性能体现的一个指标,良好的开端是高效生长、机体健康和最佳屠宰时间的关键。
图2 .碳水化合物酶复合物增加了所有胎次组仔猪的窝增重
研究证明,为了使母猪能够更好地哺育仔猪及在仔猪断奶后能以良好的身体状况恢复生产,母猪需要摄取足够的营养物质来产奶,而不是为了降低体重损失。尽管在哺乳期开始时增加了饲料的摄入量,母猪仍然会损失10%的体重。减少身体储备的损失对随后的生殖周期有重大影响。因此,提高母猪营养摄入量的方法将有利于健康和经济效益。
从meta分析看出,很明显,添加碳水化合物酶复合物是一种解决方案,以减轻由母猪高生产力造成的影响。补充物降低了母猪的体重损失,增加了饲料的消化率;通过增加每天的能量摄入,碳水化合物酶有助于母猪的发育;它还导致了仔猪窝重的增加,这是预测猪只未来生长性能的一个指标,对养猪户来说具有重要的经济意义。
Sows in top condition during lactation
Sow performance has increased in recent years. Improvements in genetics, nutrition and health status have driven these changes. Some nutritional solutions to deal with the increased demands for sows are still underutilised, carbohydrases being one of them.
Pig producers need sows to rear healthy and fast-growing piglets. A sow’s biggest challenge is to do that without losing too much body protein reserves, so that she returns to service quickly. Therefore, feed intake and nutrient use need to be optimised.
The digestibility of sow diets is affected by their capacity to digest non-starch polysaccharides (NSPs). As anti-nutrients, they reduce digestibility of the diet by nutrient entrapment, changes in diet viscosity and fermentation in the high gut. Carbohydrase addition is virtually standard in broiler diets and common in growing pig diets. Nutritionists, however, do not always value its effect in adult animals like sows. However, their use is justified since sow feed is usually highly fibrous and feed intake often limited.
Performance aims of sows
During lactation, the sows’ energy requirements increase dramatically. However, feed intake is self-limited during the first few days post-farrowing. During those significant metabolic changes, the mobilisation of body reserves is required. If this negative energy balance persists, then sows lose weight and milk production is affected. This is detrimental to both the sow and her piglets.
Quantity and quality of sow milk play a key role for the health and growth of her piglets. From an economic point of view, the number and weight of a litter at weaning, is an indicator of the future performance of sows. If sows are not in good body condition when their piglets are weaned, they will take longer to return to service. If the cycle repeats, long term reproductive performance is reduced along with her longevity in the herd. Adding a carbohydrase complex in lactating sow diets has been shown to increase the digestibility of protein and energy during lactation. With feed intake an issue for lactating sows, enzymes are added on-top of the existing formulation to maximise nutrient release from the diet. Up until recently, however, there were relatively few scientific studies to this approach. Therefore, several scientific studies were conducted, to evaluate the effect of a specific carbohydrase complex* on body condition, nutrient digestibility and piglet performance in lactating sows, under different conditions. These studies were included in a meta-analysis, consisting the eight trials. The results are presented below.
Parity principles
Parity has a large effect on a sow body condition at both the start and end of lactation. Being younger, primiparous sows have less body reserves to draw on. Sows in their first and second parities also are often not eating enough feed to meet their requirements for energy and amino acids. In the meta-
analysis, sows were put into three groups based on parity. Group 1 contained primiparous sows; group 2 was made up of second and third-parity sows; sows at parity four or higher were put into group 3.(转自:猪营养国际论坛)