Spineless cactus (Opuntia ficus-indica) and saltbush (Atriplex halimus L.) as feed supplements for fattening Awassi male lambs: effect on digestibility, water consumption, blood metabolites, and growth performance

Adapting to Climate Change with Opuntia

Adapting our food production chain and increasing the flora and fauna's livelihood in climate change-affected areas using Opuntia is not only theoretical but already exists in practice in many places. This cactus grows in unsuitable soil for most species as it is adapted to arid and semi-arid soils and hot weather. In these regions, Opuntia protects from erosion and contributes to soil health. The usage of this plant as fodder is also discussed, with immense potential in substituting a part of livestock's diet and even increasing the quality of the animal's by-products and decreasing water consumption. This would result in a feed that is low-cost and has a lower environmental impact. It is to be noted that Opuntia has a high potential as an invasive species, with caution always being recommended when dealing with this specie. The high content of specific compounds, such as proline, indicaxanthin, and betanin, found in Opuntia ficus-indica, influence the plant's adaptation to unfavourable conditions. This collective evidence depicts Opuntia as a crop that can battle climate change and ensure food security.

Opuntia spp. as Alternative Fodder for Sustainable Livestock Production

During the past decades, livestock production has increased significantly, which has led to the degradation of rangelands due to overgrazing. The lack of water in several arid areas has led to a decline in crop and animal husbandry. As a consequence, the demand for drought-resistant crops has increased significantly so as to keep crop and animal husbandry systems viable and sustainable. Cactaceae have adaptive characteristics that ensure their development progress under drought conditions. The present review provides information on the nutritive value of Opuntia in animal fodder production, its effects on animal performance, and the quality of the animal-derived products. In conclusion, the use of Opuntia as innovative alternative feed would render animal production systems more sustainable.

Intake, digestibility, nitrogen balance and performance of crossbreed Boer goats fed with diets containing saltbush (Atriplex nummularia L.) and spineless cactus (Opuntia ficus-indica)

Saltbush and spineless cactus are adapted to arid and semiarid regions and used as an important forage resource in ruminants' diet. However, spineless cactus restricts production due to its low crude protein and NDF levels and high salt and oxalate contents, which can limit the digestibility and intake of dietary nutrients. Therefore, this experiment was conducted to evaluate the best ratio levels of saltbush associated with spineless cactus in diets for crossbreed Boer goats through ingestion, water balance, digestibility, nitrogen balance, growth and carcass weight. Twenty-four castrated crossbred Boer (Boer × Brazilian native) goats 6 months of age and average body weight of 20.28 kg were utilized. The animals were weighed and distributed in randomized blocks in four experimental diets with saltbush of 8.4, 18.8, 31.2 and 48.3%. The addition of saltbush hay promoted quadratic behaviour (P < 0.05) in intake of dry matter and nutrients. There was no effect (P < 0.05) from the addition of saltbush hay on the digestibility of organic matter, total carbohydrates, non-fibrous carbohydrates and neutral detergent fibre, whereas there was an increase in dry matter. The crude protein digestibility behaved quadratically (P = 0.06), where the maximum digestibility was obtained with the addition of 31.2% of hay. The balance and net nitrogen utilization presented a quadratic effect (P < 0.01). Saltbush in rations for goats presented promising results, the growth rate (0.15 kg/day) obtained in diet with a lower proportion of saltbush, would satisfy smallholders when considering that this species, associated with spineless cactus, may reduce the use of concentrate feeds; however, the diet with 31.2% of saltbush hay provided the biggest gain in body and carcass weight of the goats.

Dry matter intake, digestibility, nitrogen utilization and fermentation characteristics of sheep fed Atriplex hay-based diet supplemented with discarded dates as a replacement for barley grain

This experiment aimed to investigate the effects of substituting barley grain with discarded dates on intake and digestibility, nitrogen (N) utilization and fermentation characteristics of sheep fed Atriplex hay-based diets. Four Barki sheep (50.9 ± 2.93 kg of body weight (BW)) fitted with rumen cannula were used in a 4 × 4 Latin Square design with 23-day periods. Four isonitrogenous (~140 g crude protein (CP)/kg of dry matter (DM)) experimental diets were formulated with Atriplex hay, and dietary sugar content was increased by replacing barley grain with discarded dates (the proportions of discarded dates in the diet were 0, 93, 187 and 280 g/kg DM). Nutrient intakes were not influenced by diet. Organic matter, CP and neutral detergent fibre digestibility increased (p < 0.05) linearly and DM digestibility tended to increase with increased dates inclusion. Ruminal pH and molar proportion of butyrate increased (p < 0.05) linearly with increasing levels of dates inclusion, whereas ruminal ammonia-N decreased (p < 0.05) linearly. Total volatile fatty acid concentration was unaffected. Microbial protein synthesis (MCP) increased linearly and efficiency of microbial protein synthesis tended to increase as discarded dates increased. Total N intake was not affected by diets whereas, urinary N, urea-N and total N execrations linearly decreased (p < 0.05) with higher amounts of dates in the diets. Blood urea-N tended to decrease with increasing levels of dates. It could be concluded that replacing 100% barley grain with discarded dates as a source of soluble carbohydrates can enhance the utilization of N in Atriplex hay-based diet and consequently improve digestibility and MCP.

Nutritive Value, In Vitro Fermentation, and Methane Production of Cactus Cladodes, Sugarcane Bagasse, and Urea

Simple Summary

Cyclical droughts affecting arid and semiarid regions promote direct negative impacts on agriculture, with deficits of water availability for the maintenance of crops destined for human supply and animal production, with direct and indirect socioeconomic effects. Although livestock rearing is one of the few viable economic activities for these regions, forage production in terms of quantity and quality is a critical obstacle to support the herd over the year. Research was developed to find a forage adapted to these climates. Cactus cladodes have been used as a traditional ingredient in ruminant diets in dry areas as a solution to forage scarcity. Many traditionally used sources of forage, fresh or conserved, can be added to diets with cactus. However, the limiting factor to their inclusion would be market availability and price. This study showed that cactus cladodes associated with sugarcane bagasse (a high available crop residue) present the same nutritive value of conserved crops as silages and hay. Cactus (Opuntia and Nopalea) are essential for ruminant production systems in arid and semiarid regions due to the limitation of forage production caused by the low precipitation.

Abstract

This study evaluated the effect of different roughages fed to sheep on nutrient and water intake, ingestive behavior, nitrogen balance, microbial protein synthesis, fermentation parameters, and methane production using an in vitro gas production system. The treatments consisted of five diets: cactus cladodes Nopalea (NUB) and Opuntia (OUB), both with the addition of sugarcane bagasse (SB) and urea/ammonium sulfate (urea/as); Tifton hay (TH); corn silage (CS); and sorghum silage (SS), also with added urea/as. The NUB provided greater (p ≤ 0.03) intakes of dry matter (1024 g/d), digestible organic matter (670 g/d), and crude protein (161 g/d) than those on the SS. The NUB provided greater (p < 0.01) dietary water intake (3023 g/d) than TH. The time spent on rumination was shorter (p < 0.01), and the idle time was longer in animals fed NUB and OUB than TH and CS. Microbial protein synthesis was not affected (p = 0.27). The final pH (6.4) of the incubation fluid and the concentration of NH₃-N (39.05 mg/dL) were greater for NUB and OUB. Ruminal parameters and methane production were little or not affected by tested forages. We recommend using cactus cladodes in combination with sugarcane bagasse and urea/as in sheep diets.

Carcass traits and meat quality of lambs fed with cactus (Opuntia fícus-indica Mill) silage and subjected to an intermittent water supply

The present study aimed to evaluate the effect of cactus silage and an intermittent water supply for lambs on carcass traits and meat quality. Thirty-six crossbreed lambs with an initial average weight of 19.8 ± 2.1 kg and average age of 6 months were randomly assigned to a 3 × 3 factorial design comprising three addition ratios of cactus silage to the diet (0, 21, and 42% based on dry matter) and three water supply intervals (0, 24, and 48 h) with four replicates. There was no interaction (P > 0.05) between the cactus silage ratio and intermittent water supply for any of the evaluated variables, with the exception of the yield of the half carcass commercial cuts. There was no significant effect of intermittent water supply (P > 0.05) on the carcass characteristics or meat quality. The addition of forage cactus silage as a substitute for Tifton hay affected the morphometric measurements (P < 0.05) and carcass compactness index (P < 0.05). The addition of 42% cactus silage to the diet increased (P < 0.05) the rib eye area (13.98 cm²). The addition of cactus silage as a substitute for Tifton hay positively affected (P < 0.05) the carcass weight of commercial cuts of the lambs. To the physical and chemical parameters of the Longissimus lumborum, the addition of 42% cactus silage to the diet reduced the color meat parameters (P < 0.05) and pH_{0 and 24h}, cooking losses, and shear force were not affected (P > 0.05). The addition of forage cactus silage to the lambs’ diet affected (P < 0.05) the composition of some saturated fatty acids in the meat. A water supply interval of up to 48 h does not influence carcass characteristics and meat quality. Therefore, the use of cactus silage can be recommended in situations of water scarcity without harming the production or meat quality of crossbreed lambs.