Comparative Study of Carcass Characteristics and Meat Quality of Local Mediterranean Donkey Breeds.

This study aimed to evaluate carcass and meat quality traits in Masri (n = 14) and North African (n = 14) male donkeys, raised in a semi-intensive breeding system, grazing on mountainous areas, with supplementation of 1 kg of barley per day per animal, slaughtered at 5 (±0.48) years old. Compared to Masri, the North African population exhibited higher (p < 0.05) final body weights (181.7 ± 2.1 and 212.5 ± 7.6 kg) and cold carcass weights (101.7 ± 1.3 and 116.2 ± 4.5 kg), but lower (p < 0.05) cold dressing percentages (56.0 ± 0.4 and 54.6 ± 0.4%). Meat quality analyses showed higher (p < 0.05) cooking loss values in Masri meat (43.9 ± 0.8 vs. 39.9 ± 1.2%). Among the meat color parameters, the hue value was higher (p < 0.05) in North African samples (0.42 ± 0.01 vs. 0.39 ± 0.1). Meat from North African donkeys had higher (p < 0.05) dry matter, fat, and protein contents. Meat amino acid analysis revealed abundant levels of lysine, leucine, and methionine, in both populations. Donkey meat from both populations presented a high polyunsaturated fatty acids content, resulting in polyunsaturated fatty acids/saturated fatty acids and omega 6/omega 3 ratios for all breeds close to the recommended values for human health. Atherogenic and thrombogenic indices were also suggested to have positive effects on consumers' artery health. The characteristics of donkey meat present intriguing nutritional aspects compared to ruminant meat, and its production should be encouraged in the rural development of inner-Mediterranean areas.

Diffusion tensor imaging tractography in the one-humped camel (Camelus dromedarius) brain.

Introduction: Tractography is a technique used to trace the pathways of the brain using noninvasive diffusion tensor imaging (DTI) data. It is becoming increasingly popular for investigating the brains of domestic mammals and other animals with myelinated fibers but the principle of DTI can also apply for those with unmyelinated fibers. In the case of camels, DTI tractography is a promising method for enhancing current knowledge of the brain's structural connectivity and identifying white-matter tract changes potentially linked to neurodegenerative pathologies. The present study was therefore designed to describe representative white-matter tracts in the one-humped camel DTI tractography. Methods: Post mortem DTI was used to obtain images of two one-humped camel brains using a 3 Tesla system. T2-weighted images were also acquired to identify regions of interest for each fiber tract and a fiber dissection technique was used to complement the DT images. The main association, commissural, and projection fibers were reconstructed and superimposed on T2-weighted images or fractional anisotropy maps. Results: The results of the present study show the reconstruction of the most representative tracts, ie the cingulum, the corpus callosum and the internal capsule, in the one-humped camel brain using DTI data acquired post mortem. These DTI results were compared to those from fiber dissection. Discussion: Anatomy of the cingulum, corpus callosum and internal capsule correlates well with the description in anatomical textbooks and appears to be similar to fibers describe in large animals. Further research will be required to improve and validate these findings and to generate a tractography atlas based on MRI and histological data, as such an atlas would be a valuable resource for future neuroimaging research.

Bioconversion of alperujo into an alternative feed for ruminants by pretreatment with live yeasts and/or exogenous fibrolytic enzymes.

Extraction of olive oil through a two-stage centrifugation process produces a large amount of phytotoxic waste known as alperujo. This research was performed to bioconvert alperujo into enriched ruminant feed by pretreatment with exogenous fibrolytic enzymes (EFE) or/and live yeasts (LY). These additives were used in a completely randomized design with 3 EFE doses (0, 4, and 8 µl/g dry matter) and 3 LY doses (0, 4, and 8 mg/g dry matter) in a 3 × 3 factorial arrangement. Fermented alperujo with both EFE doses converted some of their hemicellulose and cellulose to simple sugars and increased bacterial abundance in the rumen. As a result, it shortens the lag time of rumen fermentation, increases the rate and amount of rumen fermentation, and improves digestibility. This improvement provides additional energy that can be used by ruminants to produce milk and by rumen microbiota to produce short-chain fatty acids. Fermented alperujo with a high dose of LY decreased their antinutritional compounds and reduced their high content of lipid. In the rumen, this waste became rapidly fermentable, and rumen bacteria became more abundance. Fermented alperujo with a high dose of LY + EFE accelerated rumen fermentation and improved rumen digestibility, energy available for milk production, and short-chain fatty acids compared to the use of LY or EFE alone. This synergistic interaction between these two additives increased protozoa abundance in rumen and the ability of rumen microbiota to bioconvert ammonia-nitrogen to microbial protein. Ultimately, fermentation alperujo with EFE + LY is a good strategy with minimum investment for a social sustainable economy and environment.

Study of the influence of exogenous fibrolytic enzyme additive on chemical composition, fermentation characteristics, and nutritional value of brewer's spent grain.

This study explores the influence of different doses of two exogenous fibrolytic enzyme (EFE) additives (liquid (EFE1: 1, 2, and 4 µΙ/g DM (dry matter)) and powder (EFE2: 1, 2, and 4 mg/g DM)) on the chemical composition, fermentation characteristics, and nutritional value of brewer's spent grain (BSG). The results indicate that EFE1 at low doses does not affect the chemical composition, fermentation characteristics, and the nutritional value of BSG. The medium dose EFE1 decreases the fiber compound but increases the nonfiber carbohydrates (NFC) and soluble dry matter. Also, this dose modified the fermentation of BSG by increasing the amount of gas and its fermentation rate and decreasing the time between the inoculation and start of fermentation. Therefore, it increases the digestibility, metabolizable energy, net energy-lactation (NEL), total volatile fatty acids, and the microbial crude protein production of BSG. The high dose of EFE1 decreases the fiber compound and increases the nonfiber carbohydrates and soluble dry matter; however, it also decreases the potential of gas production and does not affect the nutritional value of BSG. For EFE2, all the doses do not modify the chemical composition, fermentation characteristics, and the nutritional value of BSG. These results suggest that the effectiveness of EFE varied, depending on the type of EFE and dose. Increase in the nutritional value of BSG by EFE1 at the medium dose can encourage breeders to use these wastes as feed at low cost in cow nutrition.

In vitro study on the effects of exogenic fibrolytic enzymes produced from Trichoderma longibrachiatum on ruminal degradation of olive mill waste.

Olive mill waste is low-quality feed and rarely used in ruminant nutrition because of its high lignocellulose content, the existence of anti-nutritional factors such as total polyphenol and condensed tannin, and low protein contents. This in vitro research was conducted to valorize this waste (crude olive cake, extracted olive cake, and olive leaves) using an exogenous fibrolytic enzyme produced from Trichoderma longibrachiatum in ruminal nutrition. The enzymatic activity of this additive was 1161 units of endoglucanase per millilitre, 113 units of exoglucanase per millilitre, and 2267 units of xylanases per millilitre. This treatment was applied by spraying substrates with four doses: 0 (control), 1 (low), 2 (medium), and 4 µ L g - 1 µ L g - 1  (high) of dry matter olive mill waste in an air-conditioned room at 26  ∘ C for 12 h before in vitro incubation. For the crude olive cake, this additive at high doses increased degradation of 14 % of cellulose and 8 % of hemicellulose compared with the control at 12 h before the in vitro incubation. Consequently, it increased dry matter solubility and reduced sugars at this period compared to the control. Upon ruminal incubation, the high dose of exogenous fibrolytic enzyme increased the gas production from the immediately soluble fraction and insoluble fraction, the rate of gas production for the insoluble fraction, the dry matter degradability by 26 %, the organic matter degradability by 24 %, the metabolizable energy value by 28 %, and the microbial crude protein production by 24 % compared with the control. For olive leaves, an exogenous fibrolytic enzyme at medium dosage can also hydrolyse the hemicellulose compound, release fewer sugars, and increase dry matter solubility compared with the control at 12 h before the in vitro incubation. Upon in vitro incubation, the medium dose increased the gas production from immediately soluble and insoluble fractions, the rate of gas production for the insoluble fraction, the dry matter degradability by 13 %, the organic matter degradability by 11 %, the metabolizable energy value by 12 %, and the microbial crude protein production by 12 % compared with the control. However, the highest dose altered the gas production from insoluble fractions and decreased microbial crude protein production by 6 % compared with the control. Under the same conditions, an exogenous fibrolytic enzyme applied to extracted olive cake did not produce any effect in the chemical composition and nutritional value. These results showed clearly that effectiveness of exogenous fibrolytic enzyme varied with incubated waste. Increasing the nutritional value of crude olive cake and olive leaves using an exogenous fibrolytic enzyme can encourage breeders to use this waste as feed at a low cost in animal nutrition. This valorization of waste is a good solution to reduce pollution of soils and groundwater caused by throwing out this polluted waste into the environment.

Influence of adding fibrolytic enzymes on the ruminal fermentation of date palm by-products.

This study was conducted in order to assess the influence of four doses (0, 0.5, 1, and 2 mg (g dry matter) - 1 of commercial fibrolytic enzymes (MAXFIBER-I ® , SHAUMANN GmbH, Wahlstedt, Germany) on in vitro fermentation of date palm (Phoenix dactylifera) by-products: date kernels, wasted dates, floral stems, and palm fronds. Rumen contents were obtained from two non-lactating Holstein cows. Enzyme supplementation to by-products was carried out 12 h prior to incubation. Compared to the control, the enzymatic supplementation quadratically increased the extent but not the gas production rate of date kernel fermentation. Indeed, the potential gas production increased notably by 14.8 % with the lowest enzymes dose following recorded gas production after 48, 72, and 96 h of incubation. The estimated organic-matter digestibility, metabolisable energy, and total volatile fatty acids in the incubation fluid tended to be increased with the lowest dose by 7.8 %, 8.4 %, and 13.9 % respectively. For the wasted dates, this feed additive tended to linearly increase the gas production rate of fermentation with the highest dose. On the other hand, this supplementation had no effect on the ruminal fermentation of the floral stems and palm fronds. The exogenous fibrolytic enzymes were more effective on fibrous but not on lignified date palm by-products.