Effect of Marine Algae Supplementation on Somatic Cell Count, Prevalence of Udder Pathogens, and Fatty Acid Profile of Dairy Goats' Milk

Algae-derived compounds: Bioactivity, allergenicity and technologies enhancing their values

As a rapidly growing source of human nutrients, algae biosynthesize diverse metabolites which have promising bioactivities. However, the potential allergenicity of algal components hinder their widespread adoption. This review provides a comprehensive review of various macro and micronutrients derived from algal biomass, with particular focus on bioactive compounds, including peptides, polyphenols, carotenoids, omega-3 fatty acids and phycocyanins. The approaches used to produce algal bioactive compounds and their health benefits (antioxidant, antidiabetic, cardioprotective, anti-inflammatory and immunomodulatory) are summarised. This review particularly focuses on the state-of-the-art of precision fermentation, encapsulation, cold plasma, high-pressure processing, pulsed electric field, and subcritical water to reduce the allergenicity of algal compounds while increasing their bioactivity and bioavailability. By providing insights into current challenges of algae-derived compounds and opportunities for advancement, this review contributes to the ongoing discourse on maximizing their application potential in the food nutraceuticals, and pharmaceuticals industries.

Changes in the rumen and milk fatty acid profile and milk composition in response to fish and microalgae oils supplementation to diet alone or combination in dairy goats

Dietary fat supplementation in the ruminant diet is known to be a good strategy to increase beneficial milk fat compounds such as polyunsaturated fatty acids (PUFA) and conjugated linoleic acid (CLA). To the best of our knowledge, this is the first study to compare and combine fish oil (FO) and Schizachyrium microalgae oil (MA) supplementation to the diets of dairy goats. This study aimed to investigate the inclusion of FO, MA, and their combinations in the diets for effects on performance, milk composition, milk fatty acids, ruminal biohydrogenation, and fermentation parameters in dairy goats. Four cannulated Saanen dairy goats in the second lactation with a daily 3.25 ± 0.10 L milk yield and 45.08 ± 0.5kg body weight were assigned to four treatments: (1) no lipid supplementation (CON), (2) supplementation with 20 g/kg of FO, (3) 20 g/kg of MA, (4) 10 g/kg FO + 10 g/kg MA (FOMA). Milk and fatty acid composition were determined in samples taken from three consecutive days of milking after 21 days of adaptation. On the same days, ruminal fatty acids were determined. Dietary oil supplementations did not affect the performance parameters in dairy goats. However, fat yield decreased in FOMA. The oil supplementations did not affect the milk composition. However, cholesterol in milk increased in FO (P < 0.05). C16:0 FA in milk increased in MA. C18:0 FA in milk was lowest in MA. The highest milk trans-11 C18:1 FA was in the MA group. Cis-9, trans-11 CLA, trans-10, cis-12 CLA, and ∑PUFA increased in milk with oil supplementations to diet. Milk ∑SFA was the lowest in the FO group. Ruminal C18:0 fatty acid was decreased in oil supplementations to diet. Ruminal trans-11 C18:1, cis-9, trans-11 CLA, trans-10, and cis-12 CLA were increased in oil-supplemented groups. Ruminal fermentation parameters were not affected by oil supplementation to diet; however, there was a propionate increase in the MA group. The serum glucose and cholesterol levels were not affected by oil supplementation to diet.

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.

Changes in Chemical Composition and Fatty Acid Profile of Milk and Cheese and Sensory Profile of Milk via Supplementation of Goats' Diet with Marine Algae

The aim of the present study was to assess the effects of the low level of Schizochytrium limacinum marine algae (daily 5 g per animal) on the milk, cheese, and whey composition; fatty acid profile of milk and cheese; and the sensory profile of goat milk using an e-nose device. Thirty Alpine goats were randomly divided into two groups: the control group (C, n = 15)-fed grass with daily 600 g concentrate and the experimental group (MA, n = 15) who received the same forage and concentrate supplemented with 5 g/head/day marine algae. Animals were kept indoors and the investigation period lasted 52 days, including the first six weeks as the period of adaptation and the last 10 days as the treatment period. During the adaptation period, bulk milk samples from each group were collected once a week (0, 7, 14, 21, 28, 35, and 42 d), while during the treatment period (10 days), bulk milk samples from each group were taken every day, and cheese samples were processed from bulk milk each day from both groups. Marine algae supplementation had no negative effect on milk composition. In contrast, the marine algae inclusion significantly elevated the fat and protein content of whey and the protein content of cheese, as well as the recovery of fat and protein in the curd, while increasing the cheeses' moisture content on a fat-free basis. The marine algae supplementation significantly increased the docosahexaenoic acid (DHA) and the rumenic acid (CLA c9t11) concentrations and decreased the n-6/n-3 ratio in the milk and cheese. There were no significant differences between the C and the MA group with regard to the sensory profiles of the milk. It can be concluded that the milk obtained from goats given daily supplementation of 5g of MA has a fatty acid profile more beneficial to human health, without any negative effects on the milk's aromatic components.

Effect of short-term nutritional supplementation of green microalgae on some reproductive indicators of Anglo-Nubian crossbred goats

Background and Aim: Despite the wide spectrum of uses, one of the chief drawbacks to expanding microalgae as a food supplement in livestock is the lack of a regimen protocol with established dosage and time length of supplementation. Therefore, this study aimed to investigate the effect of short-term supplementation with increasing doses of microalgae on ovarian response in goats reared in northeast Brazil. Materials and Methods: Twenty-eight goats had their follicular waves synchronized using three injections of a prostaglandin analog at 7-day intervals. Goats were allocated to groups that received daily oral Chlorella supplementation for 7 days, respectively: 5 g, GMA5 group (n = 7), 10 g (GMA10; n = 7), and 20 g (GMA20; n = 7). The control group (GMA 0; n = 7) received a drench of water. Results: The groups showed a quadratic increase (p = 0.0156) in kidney fat thickness but there was a significant reduction in dry matter intake in the GMA20 group. The GMA20 group showed higher glucose levels and glutathione peroxidase (p < 0.05). There was a decrease in plasma cholesterol (p < 0.05) in the 10 and 20 g treatments. The number of total follicles increased quadratically. Follicles <3 mm increased linearly (p = 0.0113) for microalgal supply. The GMA10 and GMA20 groups had the highest values (p < 0.05) among the treatments. After inducing ovulation, there was a significant increase in follicles >3 mm in the GMA10 group, which also showed a greater (p < 0.05) area of intraovarian blood perfusion and pulsatility index of the ovarian artery. Conclusion: We conclude that for 7 days of supplementation, the administration of 10 g of microalgae appears to be the most efficient dosage for stimulating the ovarian response in tropical goats. Keywords: Doppler, follicles, goat, microalga, ovarian blood flow, ovarian response.

Effect of short-term nutritional supplementation of green microalgae on some reproductive indicators of Anglo-Nubian crossbred goats

Background and Aim

Despite the wide spectrum of uses, one of the chief drawbacks to expanding microalgae as a food supplement in livestock is the lack of a regimen protocol with established dosage and time length of supplementation. Therefore, this study aimed to investigate the effect of short-term supplementation with increasing doses of microalgae on ovarian response in goats reared in northeast Brazil.

Materials and Methods

Twenty-eight goats had their follicular waves synchronized using three injections of a prostaglandin analog at 7-day intervals. Goats were allocated to groups that received daily oral Chlorella supplementation for 7 days, respectively: 5 g, GMA5 group (n = 7), 10 g (GMA10; n = 7), and 20 g (GMA20; n = 7). The control group (GMA 0; n = 7) received a drench of water.

Results

The groups showed a quadratic increase (p = 0.0156) in kidney fat thickness but there was a significant reduction in dry matter intake in the GMA20 group. The GMA20 group showed higher glucose levels and glutathione peroxidase (p < 0.05). There was a decrease in plasma cholesterol (p < 0.05) in the 10 and 20 g treatments. The number of total follicles increased quadratically. Follicles <3 mm increased linearly (p = 0.0113) for microalgal supply. The GMA10 and GMA20 groups had the highest values (p < 0.05) among the treatments. After inducing ovulation, there was a significant increase in follicles >3 mm in the GMA10 group, which also showed a greater (p < 0.05) area of intraovarian blood perfusion and pulsatility index of the ovarian artery.

Conclusion

We conclude that for 7 days of supplementation, the administration of 10 g of microalgae appears to be the most efficient dosage for stimulating the ovarian response in tropical goats.

Enhancing Milk Production by Nutrient Supplements: Strategies and Regulatory Pathways

The enhancement of milk production is essential for dairy animals, and nutrient supplements can enhance milk production. This work summarizes the influence of nutrient supplements-including amino acids, peptides, lipids, carbohydrates, and other chemicals (such as phenolic compounds, prolactin, estrogen and growth factors)-on milk production. We also attempt to provide possible illuminating insights into the subsequent effects of nutrient supplements on milk synthesis. This work may help understand the strategy and the regulatory pathway of milk production promotion. Specifically, we summarize the roles and related pathways of nutrients in promoting milk protein and fat synthesis. We hope this review will help people understand the relationship between nutritional supplementation and milk production.

The Effect of Dietary Inclusion of Microalgae Schizochytrium spp. on Ewes’ Milk Quality and Oxidative Status

An unprecedented challenge for nutritionists arises during the 21st century in order to produce highly nutritious and functional food which promotes human health. Polyunsaturated fatty acids (PUFA) that are highly contained in microalgae have broadly been confirmed for preventing cardiovascular diseases and regulating immune-oxidative status. However, their optimum dietary inclusion level needs to be defined since PUFA are prone to oxidation. For this purpose, 24 cross-bred dairy ewes, were separated into four groups (n = 6) and were fed with different levels of microalgae Schizochytrium spp. [0 (CON, no microalgae), 20 (SC20), 30 (SC30) and 40 (SC40) g/ewe/day] for 60 days. The results showed that although the production parameters were not impaired, milk fat content was decreased in medium and high-level supplemented groups while protein content was suppressed only for the medium one. Concerning the fatty acids (FA) profile, the proportions of C_14:0, trans C_18:1, trans-11 C_18:1, cis-9, trans-11 C_18:2, trans-10, cis-12 C_18:2, C_20:5 (EPA), C_22:5n-6 (DPA), C_22:6n-3 (DHA), the total ω3 FA and PUFA were significantly increased, while those of C_18:0, cis-9 C_18:1 and C_18:2n-6c were decreased in the milk of treated ewes. Additionally, in the S40 group an oxidative response was induced, observed by the increased malondialdehyde (MDA) levels in milk and blood plasma. In conclusion, the dietary inclusion of 20 g Schizochytrium spp./ewe/day, improves milks’ fatty acid profile and seems to be a promising way for producing ω3 fatty acid-enriched dairy products.

Dietary strategies to enrich milk with healthy fatty acids – a review

Feed is the main factor impacting the composition and quality of milk of dairy animals. Therefore, the present review explores the effects of feed and nutrition on milk fat content and levels of healthy fatty acids (FA) in milk consumed by humans. Milk and dairy products are two main sources of healthy and unhealthy FA in human nutrition. The concentrations of FA in milk depend mainly on diets; therefore, milk FA concentrations and ratios can be greatly altered by some feeding strategies. Dietary supplementation of the diets of dairy livestock with vegetable seeds or oils, microalgae and phytogenic feed additives, and feeding of some grasses can enhance the contents of healthy FA, including n-3 FA, α-linolenic acid, conjugated linoleic acid (CLA) and, generally, unsaturated FA in milk and dairy products. Enrichment of milk with healthy FA may make milk a source of anticarcenogens (CLA and polyphenols) for human health. This review, therefore, focusses on the current research findings on enrichment of milk with healthy FA and summarizes some effective supplementation strategies to alter milk FA profile.

Alternative and Unconventional Feeds in Dairy Diets and Their Effect on Fatty Acid Profile and Health Properties of Milk Fat

Simple Summary

Milk fat is an important compound in human nutrition. From a nutritional point of view, the production of milk with a higher content of polyunsaturated fatty acids, especially of those from the n3 group, is desirable because consumption of a diet with a lower n6/n3 ratio is considered to be beneficial for humans. The most effective way to achieve this goal is via dietary manipulations in ruminants. In addition to the feedstuffs commonly used in dairy animal nutrition, there are some alternative or unconventional feedstuffs that are often used for other purposes, e.g., for the reduction of methane production in the rumen. However, such feedstuffs can also alter the fatty acid profile of milk, and thus they can have an impact on the health properties of milk fat.

Abstract

Milk fat is an important nutritional compound in the human diet. From the health point of view, some fatty acids (FAs), particularly long-chain PUFAs such as EPA and DHA, have been at the forefront of interest due to their antibacterial, antiviral, anti-inflammatory, and anti-tumor properties, which play a positive role in the prevention of cardiovascular diseases (CVD), as well as linoleic and γ-linolenic acids, which play an important role in CVD treatment as essential components of phospholipids in the mitochondria of cell membranes. Thus, the modification of the FA profile—especially an increase in the concentration of polyunsaturated FAs and n-3 FAs in bovine milk fat—is desirable. The most effective way to achieve this goal is via dietary manipulations. The effects of various strategies in dairy nutrition have been thoroughly investigated; however, there are some alternative or unconventional feedstuffs that are often used for purposes other than basic feeding or modifying the fatty acid profiles of milk, such as tanniferous plants, herbs and spices, and algae. The use of these foods in dairy diets and their effects on milk fatty acid profile are reviewed in this article. The contents of selected individual FAs (atherogenic, rumenic, linoleic, α-linolenic, eicosapentaenoic, and docosahexaenoic acids) and their combinations; the contents of n3 and n6 FAs; n6/n3 ratios; and atherogenic, health-promoting and S/P indices were used as criteria for assessing the effect of these feeds on the health properties of milk fat.