Adaptation of Livestock to New Diets Using Feed Components without Competition with Human Edible Protein Sources—A Review of the Possibilities and Recommendations

Livestock feed encompasses both human edible and human inedible components. Human edible feed components may become less available for livestock. Especially for proteins, this calls for action. This review focuses on using alternative protein sources in feed and protein efficiency, the expected problems, and how these problems could be solved. Breeding for higher protein efficiency leading to less use of the protein sources may be one strategy. Replacing (part of) the human edible feed components with human inedible components may be another strategy, which could be combined with breeding for livestock that can efficiently digest novel protein feed sources. The potential use of novel protein sources is discussed. We discuss the present knowledge on novel protein sources, including the consequences for animal performance and production costs, and make recommendations for the use and optimization of novel protein sources (1) to improve our knowledge on the inclusion of human inedible protein into the diet of livestock, (2) because cooperation between animal breeders and nutritionists is needed to share knowledge and combine expertise, and (3) to investigate the effect of animal-specific digestibility of protein sources for selective breeding for each protein source and for precision feeding. Nutrigenetics and nutrigenomics will be important tools.

Protein solubility of jackfruit seed flour: pH and salt concentration influence

Solubility is a fundamental physicochemical property of proteins because of its importance over other protein properties in foods. Water solubility characteristics determine appropriate protein extraction and fractionation conditions in foods. In this study protein solubility of jackfruit seed flour (Artocarpus integrifolia L.) was determined, combined with the effect of pH and sulfate, chloride and trisodium citrate salt concentration variations. Protein solubility was higher in more acidic (pH =2.0) and alkaline (8.0≤ pH ≥10.0) mediums, in the absence of salts. It was also verified that the best solubility conditions under pH 2.0 using trisodium citrate was at 0.25 mol/L; and for pH 6.0, it was 1.0 mol/L. For sodium chloride, the best conditions occurred at 0.25 mol/L for pH 2.0, 6.0 and 10.0; and the best solubility values using sodium sulfate under pH 4.0 and 8.0 was 0.25 mol/L; and 0.50 mol/L under pH 6.0 and 10.0. Jackfruit seeds flour can be used as an alternative source of edible protein and as a substitute for products already available in the market.

146 Net protein contribution of feedlots from 2006 to 2017

Feedlot efficiency has increased as technologies are adopted and new feed ingredients, generally byproducts, have become available and readily incorporated. To evaluate the effect of diet changes and feedlot production over time on net protein contribution (NPC), a deterministic NPC model was used. Lot level production data from 2006 to 2017 for 8 commercial feedlots was used. Ingredient and nutrient composition were collected for a representative starter and finisher diet fed for each year and feedlot combination. Net protein contribution was calculated by multiplying the ratio of human-edible protein (HeP) in beef produced to HeP in feed by the protein quality ratio (PQR). A NPC >1 indicates a production system is positively contributing to meeting human protein requirements, whereas a NPC < 1 indicates competition with humans for HeP. Regressing NPC on year evaluated temporal change in NPC, and feedlots were categorized as increasing (INC; slope > 0) or constant (CON; slope = 0). Four feedlots were categorized as INC and 4 were CON. A common slope was estimated for CON and INC for PQR (P ≥ 0.79). Slopes of INC and CON differed for byproduct and cereal grain inclusion (P ≤ 0.01). Feedlots categorized as INC reduced HeP consumed by 2.39% per year, but CON feedlots did not (0.28%). Cattle received and shipped by INC were lighter than CON cattle (P < 0.01). Both feedlot types tended to improve HeP gained (0.1 kg per year; P = 0.10). Differences in slope for INC and CON were observed for conversion efficiency of HeP (P < 0.01). Net protein contribution increased 0.027 units per year for INC (P < 0.01) and was 0.94 in 2017. Net protein contribution by the feedlot sector increased from 2006 to 2017 as a result of using less human-edible feeds to produce human-edible beef protein.

Net protein contribution of beef feedlots from 2006 to 2017

Feedlot efficiency increases as technologies are adopted and new feed ingredients, especially byproducts, become available and incorporated into diets. Byproduct availability increased in response to the renewable fuels standard of 2005, creating substantial amounts of feedstuffs best used by ruminants. Cereal grains have been partially replaced with human-inedible byproducts, as they provide comparable levels of energy in cattle diets. To evaluate the effects of changes in diet and feedlot production practices on net protein contribution (NPC) and human-edible protein conversion efficiency (HePCE) across time, a deterministic NPC model was used. NPC was assessed for the feedlot industry using lot level production data from 2006 to 2017 for eight commercial feedlots. Ingredient and nutrient composition was collected for a representative starter and finisher diet fed for each year from each feedlot. NPC was calculated by multiplying human-edible protein (HeP) in beef produced per unit of HeP in feed by the protein quality ratio (PQR). Systems with NPC >1 positively contribute to meeting human protein requirements; NPC < 1 indicates competition with humans for HeP. NPC was regressed on year to evaluate temporal change in NPC. Feedlots were categorized as increasing NPC (INC; slope > 0) or constant NPC (CON; slope = 0) according to regression parameter estimates. Four feedlots were categorized as INC and four were CON. The rate of change in PQR was similar for CON and INC (P ≥ 0.79), although rates of change among INC and CON differed for byproduct and cereal grain inclusion (P ≤ 0.01) across years evaluated. Feedlots categorized as INC reduced HeP consumed by 2.39% per year, but CON feedlots did not reduce HeP consumed each year (0.28%). Cattle received and shipped by INC were lighter than those in CON feedlots (P < 0.01). Across years, INC produced more HeP (20.9 vs. 19.2 kg/hd) than CON (P < 0.01), and both feedlot types tended to improve HeP gained over time (0.1 kg per year; P = 0.10). Differences in slope over time for INC and CON were observed for conversion efficiency of HeP (P < 0.01). NPC increased 0.027 units per year for INC (P < 0.01) and was 0.94 in 2017. NPC by the feedlot sector improved from 2006 to 2017, decreasing the amount of human-edible feeds required to produce more high-quality protein from beef.