The impact of citrus pulp inclusion on milk performance of dairy cows: A meta-analysis

Considering sustainability and circular economy, citrus pulp could become a common dairy feedstuff. Yet, there is no clear indication of the amount of citrus pulp that can be fed without compromising milk performance or that could deliver benefits. In our meta-analysis, we investigated the impact of varying citrus pulp inclusion levels, i.e., no (0 %), low (>0-10 %), medium (>10-20 %), and high (>20 %), on milk performance variables. Replacing cereal grains with citrus pulp increased pectins and sugars while decreasing starch. At the low inclusion level, citrus pulp increased milk yield without affecting feed intake. At higher inclusion levels, citrus pulp reduced feed intake and milk yield but with higher fat contents, the milk energy content was similar to no inclusion. Concluding, citrus pulp is a good energy source with lipogenic properties in dairy cows. We encourage research to fill in the existing gap of knowledge at the rumen and systemic levels.

Cocoa byproduct inclusion in dairy sheep diet: Effects on sensory, volatile, and antioxidant properties of cheese

The possibility of inclusion of agro-industrial byproducts in the diet of small ruminants represents both an economic and an environmental strategy for reducing waste management by industries and costs of feeding as well as the impact of livestock farming. Large amounts of wastes from the cocoa industry are produced annually, with a considerable part represented by cocoa bean shells, considered a suitable ingredient to be included in the diet of ruminants within the limits established by European legislation. The aim of this study was to assess the effect of including cocoa bean shells in the diet of dairy sheep on the sensory, volatile, and antioxidant properties of cheese. To this purpose, 20 lactating Comisana ewes were randomly assigned to 2 experimental groups: control (CTRL) and cocoa bean shells (CBS), and received alfalfa hay ad libitum and 800 g of conventional (CTRL) or experimental (CBS) concentrate containing 11.7% CBS to partially replace corn and barley of the CTRL concentrate. Bulk milk collected from each group was used to produce a total of 15 cheeses per group, obtained in 5 different days of cheesemaking (3 cheeses a day per group). After 60 d of aging, each cheese of each experimental group was sampled for the analyses. The results on chemical composition revealed a greater content of monounsaturated fatty acids and an increase in the nutritional indices, suggesting a favorable role of cocoa bean shell dietary inclusion on the nutritive value of cheese. The cheese sensory profile was affected by the cocoa bean shell inclusion, with more pronounced appearance, odor, aroma, and taste attributes in the product. The volatile profile showed only a few significant differences, mainly related to the cheese ripening process, and no differences were found in α-tocopherol contents in cheese fat between the 2 groups. Therefore, the inclusion of coca bean shells in the diet of dairy sheep allowed us to obtain a good-quality cheese, without altering the characteristics associated with the typical profiles of sheep cheese. Furthermore, the use of this byproduct could contribute to decreasing feed costs and waste management, representing a good practice for increasing the sustainability of dairy products.

A comparative analysis of the proximate and mineral composition of whole Citrus limon and Citrus clementina as a prospective alternative feed resource for livestock farming in South Africa

Citrus is a well-known vital fruit grown in South Africa. The presence of important bio-nutrients and metabolites within the different Citrus fruits indicates their significant nutritional qualities. This study is aimed to evaluate the proximate and mineral components of whole Citrus limon and Citrus clementina while considering them as prospective feed material for livestock farmers in South Africa. The nutritional evaluation was done using standard analytical procedures of the Association of Official Analytical Chemists (AOAC). The mineral constituents of the whole citrus samples were analyzed using inductively coupled plasma optical emission spectroscopy (ICP-OES). From the result, the nutritional analysis showed that the whole C. limon contains significantly higher moisture content (14.13 ± 0.57) and fiber content (24.48 ± 0.61) than C. clementina (11.41 ± 1.24 and 20.66 ± 1.07). Meanwhile, C. clementina had a significantly higher protein value (8.65 ± 0.04) compared to C. limon (5.53 ± 0.10). Furthermore, the whole C. clementina had significantly higher K, Na, P, Zn, and Na+/K+ (1513.33 ± 16.99, 53.33 ± 4.71, 160.00 ± 0.00, 4.80 ± 0.00, and 1.09 ± 0.01) than the whole C. limon (1356.67 ± 20.55, 30.00 ± 0.00, 133.33±4.71, 1.67 ± 0.09, and 0.80 ± 0.02), respectively. While C. limon had significantly higher Ca, Mg, Mn, and Fe (593.33 ± 4.71, 160.00 ± 0.00, 1.00 ± 0.00, and 4.53 ± 0.25) compared to C. clementina (483.33 ± 4.71, 136.67 ± 4.71, 0.80 ± 1.11, and 3.43 ± 0.05). The study revealed variations in some nutritional and mineral components of whole C. limon and C. clementina; however, both citrus fruits have the potential to be explored for more significant livestock nutritional use in South Africa.

Effect of Molasses and Dried Orange Pulp as Sheep Dietary Supplementation on Physico-Chemical, Microbiological and Fatty Acid Profile of Comisana Ewe's Milk and Cheese

The use of agro-industrial by-products for ruminant feed represents both an economical and environmental convenient way for reducing waste discharge and waste management costs for food industries. Large amounts of waste from citrus processing industries are available in Sicily, Italy. In the present study, the effect of dried citrus pulp as sheep dietary supplementation was evaluated on physico-chemical, microbiological and fatty acid composition of resulting milk and cheese. Pelleted feed integrated with molasses and blond orange pulp, replacing cane molasses, beet pulp and part of the maize and sunflower in ration, were administrated to ewes as an experimental treatment The experiment involved sixty Comisana breed sheep divided into two groups and two feeding trials (experimental and control). Ewe's milk and cheese samples were collected from January to April and analyzed for physico-chemical, microbiological and fatty acid profile composition. Results suggested that both the experimental milk and cheese were different from the controls. In particular, an increase of experimental milk yield and fat content were registered whilst the cheese samples exhibited a significant decrease of pH values and an increase in fat and protein contents. In addition, an increase of conjugated linoleic acids as well as of the oxidative stability were observed indicating the beneficial effect of dietary supplementation. Furthermore, among the main microbial groups, the experimental and control samples, no differences were detected. However, with the exception of streptococci, which was found higher in experimental cheeses, and staphylococci, which was significantly reduced by experimental feed. Moreover, the application of culture-independent methods highlighted the dominance of Lactobacillus rhamnosus/casei group in the experimental cheese, suggesting a driving role of the dietary supplementation in the cheese microbiota composition. The present study demonstrated that the inclusion of citrus by-products in the diet of small dairy ruminants is a promising feeding, which could positively affect milk composition and cheese manufacture.