**4. Conclusions**

Our research proved that the supplementation of fatty acids into the diet had no effect on daily milk yield of goats. In ALFA group, a statistically significant impact on the increase of the protein content in milk (p<0.01) during the supplementation and thereafter was observed. Fat content was increasing during the supplementation and thereafter in ALFA group, while in EPA and DHA groups, fat content significantly reduced during the supplementation with fatty acids (p<0.001) and a few days thereafter. This finding indicates that the supplementation with fatty acids (eicosapentanoic and docosahexanoic fatty acid) had a negative impact on the milk fat production. Lactose content did not change significantly during the supplementation and no differences were found among groups. Non-fat dry matter content was the highest in ALFA group, its increased value reflected even after the end of the supplementation with fatty acids.

The supplementation of α-linoleic fatty acid decreased somatic cell count in milk, even 30 days after the end of the supplementation. Statistically significant decrease of somatic cell count, compared to the period prior to the supplementation, was appeared till the 29th day after the end of the supplementation (p<0.05). The number of micro organisms in milk is the result of hygienic conditions at milking, hygiene of milking personnel, equipment, environment and hygiene of the animals. In the case of our study, it has been established that the lower number of micro organisms was the consequence of better hygiene during the experiment due to the experimentalists' presence.

The supplementation of α-linoleic, eicosapentanoic and docosahexanoic fatty acids had different effects on the composition of fatty acids in milk fat. Eicosapentanoic fatty acid supplemented into the diet of EPA group increased the following fatty acids: capric, lauric, myristic, conjugated linoleic, linoleic, γ-linolenic, cis-11,14,17-eicosatrienoic, cis-8,11,14 eicosatrienoic, arachidonic, eicosapentaenoic, docosatrienoic, docosatetraenoic, and docosapentaenoic acid. The supplementation of eicosapentanoic fatty acid decreased palmitic, stearic, and oleic fatty acid. α-linoleic fatty acid supplemented to ALFA group increased the following fatty acids: lauric, miristoleic, oleic, conjugated linoleic, linoleic, αlinoleic, γ-linolenic acid. This means that there was no elongation from α-linoleic acid into fatty acids with longer chain. A decrease was observed in myristic, palmitic, and docosatetraenoic acid. DHA group was supplemented with docosahexaenoic fatty acid where the increase of the following fatty acids was recorded: capric, lauric, myristic, palmitoleic, conjugated linoleic, linoleic, γ-linolenic, cis-8,11,14-eicosatrienoic, arachidonic, eicosapentaenoic, docosatrienoic, docosatetraenoic, docosapentaenoic, docosahexaenoic acid, while a decrease was noticed in the following fatty acids: miristoleic, palmitic, stearic, and oleic acid. In the control group, only slight variations in some fatty acid levels were recorded, which were not statistically significant.

Research showed that the supplementation of α-linoleic acid had a positive impact on reduction of the somatic cell count in goat milk. However, the surprising result was found, that the supplementation of eicosapentanoic and docosahexanoic acid did not affect the reduction of somatic cell count in the same extent. There is a question, whether this is the result of the supplement or of the n-3:n-6 ratio which changed after the supplementation. Since the ratio n-3:n-6 changed to the similar value when other fatty acids were supplemented and the effect was not the same, it seems that the n-3:n-6 ratio was not the cause of this effect. It is suggested that α-linoleic acid could be rapidly incorporated into cell membranes, which displace arachidonic acid. This is resulted in more flexible cell membranes and better antiinflammatory effect. Perhaps this mechanism was the one which contributed to the reduction of somatic cell count. For further research, it would be necessary to also include this kind of analysis. The results also showed that the transition of long chained polyunsaturated fatty acids into goat milk appeared relatively in large extent, therefore, polyunsaturated fatty acids occur in milk fat very quickly after their consumption.

## **Author details**

24 Milk Production – An Up-to-Date Overview of Animal Nutrition, Management and Health

0.57), and KONT (r=0.44) groups were statistically significant (p<0.05).

statistically significant.

statistically significant (r=-0.49).

even after the end of the supplementation with fatty acids.

**4. Conclusions** 

throughout the whole experiment only in EPA group (r=0.25 and r=0.24, respectively; p<0.01). From the 11th to the 65th day of the experiment, there were only correlations between somatic cell count and C10 in DHA group (r=-0.30), between somatic cell count and C12 in DHA group (r=-0.37), and between somatic cell count and C14 in ALFA (r=0.26) and DHA (r=-0.29) groups found statistically significant (p<0.05). From the 21st to the 65th day of the experiment, correlations between somatic cell count and C10 in EPA (r=-0.45) and DHA (r=- 0.46) groups, between somatic cell count and C12 in EPA (r=-0.43), DHA (r=-0.53), and KONT (r=0.39) groups, and between somatic cell count and C14 in ALFA (r=-0.59), DHA (r=-

Correlation between somatic cell count and C18:1 was statistically significant only in EPA group (r=-0.24) throughout the whole experiment, in DHA group (r=0.47) from the 11th to the 65th day of the experiment, and in EPA (r=0.42), ALFA (r=-0.49), and DHA (r=0.67) groups from the 21st to the 65th day of the experiment. Between somatic cell count and C18:3, the correlation was statistically significant only in ALFA (r=-0.43) group from the 11th to the 65th day of the experiment. No correlations between somatic cell count and C20:4 throughout the whole experiment were statistically significant. There were only correlations between somatic cell count and C20:4 in EPA group from the 11th to the 65th day of the experiment (r=0.36) and from the 21st to the 65th day of the experiment (r=0.66)

Statistically significant correlation between somatic cell count and monounsaturated fatty acids throughout the whole experiment was found only in ALFA group (r=-0.22) and from the 11th to the 65th day of the experiment in DHA group (r=0.50). From the 21st to the 65th day of the experiment, this correlation was statistically significant in EPA (r=0.43), ALFA (r=- 0.50), and DHA (r=0.68) groups. Between somatic cell count and polyunsaturated fatty acids, only the correlation in ALFA group from the 21st to the 65th day of the experiment was found

Our research proved that the supplementation of fatty acids into the diet had no effect on daily milk yield of goats. In ALFA group, a statistically significant impact on the increase of the protein content in milk (p<0.01) during the supplementation and thereafter was observed. Fat content was increasing during the supplementation and thereafter in ALFA group, while in EPA and DHA groups, fat content significantly reduced during the supplementation with fatty acids (p<0.001) and a few days thereafter. This finding indicates that the supplementation with fatty acids (eicosapentanoic and docosahexanoic fatty acid) had a negative impact on the milk fat production. Lactose content did not change significantly during the supplementation and no differences were found among groups. Non-fat dry matter content was the highest in ALFA group, its increased value reflected

The supplementation of α-linoleic fatty acid decreased somatic cell count in milk, even 30 days after the end of the supplementation. Statistically significant decrease of somatic cell Dragomir Kompan and Andreja Komprej *University in Ljubljana, Biotechnical faculty, Department of Animal Science, Slovenia* 

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## **Chapter 2**
