Thyroid and Lipidic Profiles in Nicastrese Goats (Capra hircus) during Pregnancy and Postpartum Period.

This study aimed to determine the thyroid and lipid profiles in 30 Nicastrese goats, along different physiological periods: before mating (nonpregnant goats), during the whole pregnancy (pregnant goats), and during postpartum and early lactation (milking goats). Blood samples were collected monthly from March 2020 to January 2021. Serum thyroid-stimulating hormone (TSH), total and free triiodothyronine (T3, fT3), and thyroxine (T4, fT4) concentrations were measured using immunoenzymatic assay kits and serum lipid panels (triglyceride (TG) and total cholesterol (tCho)) by enzymatic colorimetric method; very-low-density lipoprotein cholesterol (VLDL Cho) was calculated. Pregnant and milking goats showed the lower T3 (p < 0.0002) and T4 (p < 0.0005) concentrations, with lower BCS (p < 0.001) only in pregnant ones. Milking goats showed tCho (p < 0.006) concentrations lower than nonpregnant ones, and TG and VLDL Cho (p < 0.001) lower than both pregnant and nonpregnant goats. T4:T3 and T3:fT3 were significantly and positively correlated in both pregnancy and lactation. Under similar environmental, nutrition, and management conditions, different physiological phases play a significant role in the thyroid and lipid profiles in Nicastrese goats. These endocrine and metabolic resources could contribute to the knowledge useful for the salvage of this endangered, local, native breed.

Effect of seasonality on physico-chemical and microbiological properties of nicastrese milk and artisanal cheese.

Nicastrese is an indigenous Italian goat breed reared in the Calabria region under semi-extensive practices. From January to June, the milk yield of 400 multiparous Nicastrese goats was evaluated. In addition, tank milk and ripened cheese samples were subjected to physico-chemical and microbiological analyses with the aim to assess the effect of the seasonality on quality parameters. The volatile organic compounds profile of the ripened Nicastrese cheese samples was evaluated. Results showed that the seasonality had a significant effect on milk fat, lactose, urea, citric acid contents and acidity. Microbiological analysis of tank milk samples revealed variability among the different microbial groups investigated except for Escherichia coli. In addition, faecal coliforms and Listeria spp. were never detected. Regarding 60 days ripened cheese samples, almost all microbial groups showed a significant decrease during the analysed period, with the exception of Enterobacteria. It is interesting to note that Escherichia coli and Listeria spp. were not detected in any cheese sample investigated, confirming the cheese safety. Overall, volatile organic compounds, detected on cheese samples, decreased trough the investigated period and this behavior could be related to the feeding quality and to the milk's goat nutritional components.

Polyphasic approach to study physico-chemical, microbiological and sensorial characteristics of artisanal Nicastrese goat's cheese.

Nicastrese goat's cheese is produced in the South of Italy under traditional procedures, from raw goat milk without any starter cultures addition. Samples from milk to ripened cheese provided by 4 different farms were subjected to a polyphasic approach to study their physico-chemical, microbiological and sensorial characteristics. In addition, volatile organic compounds formation in the final products was studied. Overall, gross composition and microbiological data revealed a significant variability among samples, which was confirmed by both the volatile organic compounds generated in the final products and by the sensorial data. Conventional technique allowed us to identify 720 isolates, mainly belonging to Lactococcus lactis, Lactobacillus plantarum, Lactobacillus casei, Lactobacillus brevis, Leuconostoc mesenteroides, and Enterococcus faecalis. Culture-independent methods revealed shifts in the microbial community structure, with an increase in biodiversity of metabolically active bacterial species, from milk to cheese samples. Analysis of volatile organic compounds (VOCs) allowed the identification of 36 compounds; free fatty acids and ketones represented the main detected, followed by alcohols and esters. Moreover, statistical analysis was performed in order to correlate VOCs to bacterial species. Data showed that ester compounds as well as alcohol and aldehydes were positively correlated to NSLAB, indicating that the occurrence of L. casei, L. plantarum and L. brevis species is relevant for the VOCs formation in the final product.