Mediterranean forest rangelands offer an important feed source for goats. Concerns about grazing strategies and management schemes in order to ensure the rangeland sustainability of Southern Mediterranean forest have revived interest in the foraging behavior of goats. This study was conducted to investigate the seasonal changes of feeding behavior of grazing goats in the Southern Mediterranean forest rangeland of Northern Morocco during two consecutive years beginning in 2016. The direct observation method was used to compare diet composition, intake rate, and diet selectivity of goats during three seasons (spring, summer, and fall). Bite mass of each plant species selected by goats was estimated using hand-plucked simulation. The optimal foraging theory was used as a tool to explain the goats foraging decisions. Bite mass range was extremely wide and varied seasonally. The goats’ diet was largely composed of Cistus spp., Lavandula stoechas, Quercus spp., and Myrtus communis. The result shows that the smaller the bite mass, the higher the biting rate, leading to increased short term intake rates. The selection of various plant species during fall and summer enlarged the diet diversity of goats. As expected, goats preferred trees and some shrubs despite their low availability. Consequently, the most available species is not necessarily the most positively selected. Particular high and positive selection of Quercus suber was observed over seasons. The outcomes confirm the high adaptability and ability of goats to select a woody species across seasons. Knowledge about forage availability and the feeding behavior of goats could be used as the first guide for rangeland managers to ensure herd and forest sustainability.

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Forest rangelands contribute largely to goat diets in the Mediterranean area. Information about browsed plant quality is essential for adequate feeding management. The purpose of this study was to evaluate the temporal changes in chemical composition and in vitro digestibility of the main plant species selected by goats in the Southern Mediterranean forest rangeland during two consecutive years; these were very contrasted (dry and wet). The browsed species were composed of herbaceous, eleven shrubs, and four tree species. Overall, large variability in chemical composition, in vitro organic matter digestibility (IVOMD), and metabolizable energy (ME) was observed among species, grazing season (spring, summer, and autumn), and years within each species. Crude protein (CP) content varied from 60 to 240 g/kg dry matter (DM). The fiber fractions, except for Quercus suber, increased significantly by advancing maturity. Due to the water stress, the lignin level presented a higher value during the spring of the dry year. Condensed tannin (CT) content varied from 2 to 184 g/kg DM. CP, IVOMD, and ME showed a negative correlation with lignin and CT. Based on the results presented herein, it is concluded that the nutritive value of the browsed plant species was highest in the spring and lowest during the summer and autumn of both studied years. With a good grazing management strategy, the selected plant species by goats could guarantee high-quality feeding resources throughout the year.

Olive cake (OC) and cactus cladodes (CCs) are two alternative feed resources widely available in Mediterranean areas. Their use in ruminant diets was assessed according to their chemical composition, secondary compound levels and digestibility. The effects of the olive oil extraction period and process, and CCs age and sampling period were evaluated. OC was collected monthly, from November to January, from mills using either a mechanical press or 2-phase or 3-phase centrifugation processes. CCs were collected fortnightly according to age (young and mature) from April to June. Two-phase OC had the lowest content of dry matter (DM), the highest nitrogen-free extract (NFE) and total and hydrolysable tannins and was more rapidly fermentable. Mechanical press OC was the least digestible. OC DM, protein and NFE were affected linearly by the extraction period. Gas production (GP), in vitro digestibility parameters and dry and organic enzymatic digestibility changed with the extraction period. Therefore, OC chemical composition and in vitro digestibility depended mainly on the extraction process and period. Compared to mature CCs , young CCs contained more water, protein, ether-extract and phenolic compounds, but less ash and fibre. GP and digestibility parameters were not affected by age, but in vitro organic matter digestibility and microbial biomass production were higher in young cladodes. CCs chemical composition, GP and digestibility parameters were influenced by the collection period. Due to its limited nutritional quality, OC should be enriched in nitrogen, while CCs could be considered as highly valuable forage in ruminant diet.