IntroductionWith the dramatic rise in prices of corn, alfalfa, and other traditional feed ingredients, nutritionists are getting more creative and turning to nontraditional products (1). Agricultural residues are byproducts of cereals, sugarcane, oilseeds, oil plants, vegetables, and fruits obtained during harvesting and processing of a commodity from which human food is derived (2). These byproducts have been of interest to many researchers since the 1970s because of the desire to understand and reduce environmental waste in most countries (2,3). Using such byproducts for animal feed is a means of recycling something that otherwise, if accumulated, might cause environmental pollution (3). The almond hull is obtained by drying that portion of the almond fruit that surrounds the wooden shell and includes the exocarp and mesocarp of the fruit and can be utilized in different ways. The proportion of hull is 50.00% of the total weight of the almond (2,4). Almond and almond hull production has continuously increased over the past decades. In 2008, approximately 2,110,000 t of almonds were commercially produced in the world (5), resulting in the availability of equal tons of hulls (3). Almond hulls (AHs) were not considered as a valued feedstuff before 1948 and were used as a fuel material or were destroyed (6). The nutritional value of AHs has been determined in sheep (2,7,8), dairy cow (4), goat (9), horse (10), and pig (11), in which AHs were shown to have an energy value of 65.00% to 90.00% of barley and to be equivalent to early and mid-bloom alfalfa hay, and they were introduced as a safe and palatable feedstuff. In a study by Getachew et al. (12) about the relationships between chemical compositions of several ruminant feeds, nonfibrous carbohydrate (NFC) content of AHs (48.70%) was higher than that of alfalfa (ALF) (26.80%) and almost the same as that of sugar beet pulp (SBP) (43.80%). Crude protein (CP) contents of AHs and SBP were almost the same (8.00% and 9.00% for AHs and SBP, respectively), but were lower than that of ALF (26.00%), while neutral detergent fiber (NDF) contents of AHs, SBP, and ALF were also almost the same (33.60%, 31.80%, and 33.80% for AHs, SBP, and ALF, respectively).The nutritive value of a ruminant feed is determined by the concentrations of its chemical components, as well as their digestibility. Determining the digestibility of feeds in live animals (in vivo) is laborious and expensive, requires large quantities of feed, and is time-consuming. The in situ nylon bag technique represents a less expensive and more