Swine Management Resources - PIC


Technology advancements and large-scale research under commercial conditions is constantly allowing for the development and evaluation of different feed additives.

Exogenous phytase is used as a feed additive to hydrolyze phytic acid (phytate) and increase phosphorus availability in feed ingredients. There are multiple phytase suppliers and a comparison between phytase sources, phytase stability, as well as the effects of superdosing phytases were reviewed by Gonçalves et al. (2016a). It is important that the nutritionist be confident in the release levels associated to phytase in order to avoid Ca and P deficiencies, especially in herds with low feed intake. Heat stable sources are preferred due to increased phytase stability over time and especially in pelleted diets (Sulabo et al., 2011). Additionally, high levels of phytase may need to be used when high levels of zinc oxide are used. There is increasing evidence that increased levels of phytase in nursery diets to those beyond P and Ca release may enhance growth performance (Kies et al., 2006; Walk et al., 2012; Langbein et al., 2013; Koehler et al., 2015). However, the mechanism for such an enhancement in performance remains unclear and the magnitude of impact is dependent on the levels of P, amino acids, and other nutrients in the diet (Adeola and Cowieson, 2011). At this point, there are mixed peer-reviewed research results regarding the impact of phytase on the release of nutrients beyond phosphorus and calcium (Johnston and Southern, 2000; Holloway et al., 2015).

Ractopamine is a feed additive with proven results in finishing pigs when diets are formulated correctly. Please keep in mind that ractopamine should not be fed to replacement gilts or boars. The nutrient specifications tables at the end of this manual provide guidelines for feeding ractopamine for less than 21 days and for feeding more than 21 days prior to market. Because the SID lysine in the ractopamine diet is high, there is a risk of adding too much soybean meal and causing a yield reduction (Gaines et al., 2004 and 2007). Synthetic amino acids should be used to reduce the amount of soybean meal in diets with ractopamine. Different countries have different regulations regarding ractopamine use.

A review by Jacela et al. (2010a) suggests that the use of high levels of zinc oxide from weaning to 11.5 kg of body weight improve performance and reduce diarrhea rates. Similarly, using a copper source (i.e., 100 to 250 ppm) has been reported to increase growth performance. However, the data regarding an additive response to feeding high levels of zinc and copper simultaneously is conflicting. These high levels of zinc should not be fed for more than 20 to 25 days. Thus, current recommendation is to feed 3000 ppm of zinc from weaning to 7.5 kg, 2000 ppm of zinc from 7.5 to 11.5 kg, and 125 to 250 ppm of copper from 11.5 to 23 kg. Different countries have different regulations regarding the use of zinc and copper as growth promoter.

Eder et al. (2001) supplemented 125 mg per day for sows from weaning to farrowing and observed an improvement of 8% and 7% in litter birth weight of gilts and mature sows, respectively. These results were further supported by later research (Ramanau et al., 2002; Ramanau et al., 2008). More research is needed to validate these effects in large litter sizes.

There seems to be a reduction in mortality in finishing pigs with the use of commercially available xylanase in high-fiber diets (15% Corn DDGS and 10% wheat middlings). This has been reviewed by Boyd et al. (2015) and further research is warranted.

Swine Management Resources - PIC