Feeding and Nutritional Factors That Affect Somatic Cell Counts in Milk of Sheep and Goats.

The purpose of this quantitative review is to highlight the effects of feeding strategies using some mineral, vitamin, marine oil, and vegetable essential oil supplements and some agri-food by-products to reduce SCCs in the milk of sheep and goats. According to the results, only specific dietary factors at specific doses could reduce SCCs in the milk of dairy sheep and goats. The combination of Se and vitamin E in the diet was more effective in sheep than in goats, while the inclusion of polyphenols, which are also present in food matrices such as agro-industrial by-products, led to better results. Some essential oils can be conveniently used to modulate SCCs, although they can precipitate an off-flavoring problem. This work shows that SCCs are complex and cannot be determined using a single experimental factor, as intramammary inflammation, which is the main source of SC in milk, can manifest in a subclinical form without clinical signs. However, attention to mineral and vitamin supplementation, even in the most difficult cases, such as those of grazing animals, and the use of anti-inflammatory substances directly or through by-products, can improve the nutritional condition of animals and reduce their SCCs, offering undeniable benefits for the milk-processing sector as well.

Supplementation of by-products from grape, tomato and myrtle affects antioxidant status of dairy ewes and milk fatty acid profile.

The aim of this study was to evaluate the effect of diets containing different dried by-products on milk and blood plasma antioxidant capacity of dairy ewes. Thirty-six Sarda ewes were assigned to four treatments: control (CON; no by-product), 100 g/day of grape marc (GM), 100 g/day tomato pomace (TP) and 75 g/day of exhausted myrtle berries (EMBs). The superoxide dismutase (SOD), glutathione reductase (GR), glutathione transferase (GST) and glutathione peroxidase (GSH-Px) in blood, and SOD, GR and lactoperoxidase (LPO) in milk were determined. Total antioxidant capacity (FRAP and ABTS assays), malondialdehyde (MDA) and protein carbonyls (PCs) were also measured. Milk fatty acid profile was investigated by gas chromatography. The results showed higher antioxidant capacity measured by FRAP or ABTS assays and a reduction in MDA in GM plasma than CON. All by-products enhanced the protection of milk proteins by oxidation, as evidenced by lower values of PCs compared with CON. GM supplementation increased PUFAn-6, due to increase in C18:2n-6, the main component of GM compared with CON. All by-products did not modify the nutritional indexes of milk fat. In conclusion, dietary GM may enhance protection against oxidative condition of dairy ewes, whereas TP and EMB need further research to define the optimum inclusion level in sheep diet.

Oxidative stress and food supplementation with antioxidants in therapy dogs.

The objective of this study was to evaluate the ability of a long-term antioxidant-supplemented diet to regulate the oxidative stress and general health status of dogs involved in animal-assisted intervention (AAI) programs. Oxidative stress is a consequence of the accumulation of reactive oxygen species (ROS). Exercise-induced oxidative stress can increase muscle fatigue and fiber damage and eventually leads to impairment of the immune system. A randomized, placebo-controlled, crossover clinical evaluation was conducted with 11 healthy therapy dogs: 6 females and 5 males of different breeds and with a mean age of 2.7 ± 0.8 y (mean ± SEM). The dogs were divided into 2 groups, 1 fed a high quality commercial diet without antioxidants (CD) and the other a high quality commercial diet supplemented with antioxidants (SD) for 18 wk. After the first 18 wk, metabolic parameters, reactive oxygen metabolite-derivatives (d-ROMs), and biological antioxidant potential (BAP) levels were monitored and showed a significant reduction of d-ROMs, triglycerides, and creatinine values in the SD group (P < 0.05) and a significant increase in amylase values in the CD group (P < 0.01). At the end of this period, groups were crossed over and fed for another 18 wk. A significant decrease in amylase and glutamate pyruvate transaminase (GPT) values was observed in the CD and SD group, respectively (P < 0.05). In conclusion, a controlled, balanced antioxidant diet may be a valid approach to restoring good cell metabolism and neutralizing excess free radicals in therapy dogs.

L'objectif de la présente étude était d'évaluer la capacité d'une diète long-terme supplémentée en antioxydant à réguler le stress oxydatif et l'état de santé général de chiens impliqués dans des programmes d'intervention avec assistance animale (IAA). Le stress oxydatif est une conséquence de l'accumulation d'espèces oxygène réactive (EOR). Le stress oxydatif induit par l'exercice peut augmenter la fatigue musculaire et les dommages aux fibres et éventuellement mener à un mauvais fonctionnement du système immunitaire. Une évaluation clinique croisée, randomisée, et avec groupe témoin-placebo a été menée avec 11 chiens d'assistance en santé : 6 femelles et 5 mâles de races différentes et d'un âge moyen de 2,7 ± 0,8 ans (moyenne ± écart-type). Les chiens ont été divisés en deux groupes, un premier groupe nourri avec une diète commerciale de haute qualité sans antioxydant (DC) et l'autre groupe avec une diète commerciale de haute qualité supplémentée avec des antioxydants (DS) pour 18 semaines. Après les premières 18 semaines, les paramètres métaboliques, les métabolites dérivés d'oxygène réactive (MDOR), et les niveaux de potentiel antioxydant biologique (PAB) ont été surveillés et ont montré une réduction significative des valeurs des MDOR, des triglycérides et de la créatinine dans le groupe DS (P < 0,05) et une augmentation significative des valeurs de l'amylase dans le groupe DC (P < 0,01). À la fin de cette période, les groupes ont été croisés et nourris pour 18 semaines supplémentaires. Une diminution significative des valeurs de l'amylase et de la glutamate pyruvate transaminase (GPT) a été obtenue dans les groupes DC et DS, respectivement (P < 0,05). En conclusion, une diète contrôlée, balancée en antioxydant pourrait être une approche valide pour restaurer un bon métabolisme cellulaire et neutraliser les radicaux libres excédentaires chez les chiens d'assistance.(Traduit par Docteur Serge Messier).

Light-induced lipid oxidation in sheep milk: effects of dietary grape seed and linseed, alone or in combination, on milk oxidative stability.

The present work aimed to investigate the milk oxidative stability when the sheep diet includes a source of polyphenols (grape seed, (GS)) and a source of polyunsaturated fatty acids (linseed, (LIN)), alone or in combination (MIX) compared to a control group (CON). For this purpose light-induced oxidation in milk was studied. After 24 h of light exposure the lipid hydroperoxides increased in milk in the LIN and MIX groups. The calculated ratio between the level of lipid hydroperoxides and unsaturated fatty acids (UFAs) in milk was lower in the GS and MIX than in the LIN group. At the same time the level of the ratio between hexanal/linoleic acid in milk was lower in the GS and MIX than in the CON group. Although the dietary inclusion of grape seed did not reduce the level of lipid oxidation products in sheep milk, it effectively reduced the extent of oxidation of UFA.