Effects of season on the quality of Garfagnina goat milk

Abstract

The Garfagnina goat is an endangered native goat population from Italy. This study aims to give a contribution to the milk quality assessment of the native goat during the two productive seasons, spring and summer, and to verify the relationships between some meteorological data and physiological and milk quality parameters. Individual milk samples were taken in the two seasons. Physiological parameters and meteorological data were also registered. All the milk samples were measured for volume and analysed for: dry matter, total nitrogen, casein, ash, lactose, fat, milk fatty acid (FA) composition, number and diameter of the fat globules, and rheological parameters. There were not differences in the average diameter of the milk fat globules (2.27 ± 0.28 lm) and in milk gross composition between the two seasons, except for lactose which was significantly lower in summer. During summer a significant increase in some longchain FAs such as CLA c9,t11, C18:1 t11, C18:0, C18:3 n3, C20:0, C22:0, C22:2 was observed, whereas short-chain FAs (C6:0, C8:0, C10:0), which are responsible for the development of unpleasant aromas, as well as monounsaturated C16:1, C17:1 c9, C20:1, C22:1 and polyunsaturated FAs C20:2, C20:3 n3 decreased. The average PUFA n6/PUFA n3 ratio was 1.7 and the lowest values were recorded in summer. In summer a worsening of the clot, which was less firm, was found. Environmental parameters were found to be linked to the milk FAs, while heart rate and skin temperature were negatively linked to milk yield and lactose, respectively. ARTICLE HISTORY

Seasonal variation of fatty acids composition of milk from grazing ewes in Thessaly, central Greece

“…Sinanoglou et al, (2015) reported C18:1 trans-11 VA levels of 0.35 -0.48% FAME in milk produced by the Karagouniko sheep breed under conventional feeding conditions. Seasonal variations of C18:1 trans-11 VA levels were also reported for milk from cows (Rego et al, 2008) or goats (Salari et al, 2016) fed grazed pasture.…”

Effects of month of kidding, parity number, and litter size on milk yield of commercial dairy goats in Australia

“…Several studies have shown that seasonal variations of environmental factors such as feed quality, air temperature, relative humidity, rainfall, and solar radiation have a significant effect on milk yield and milk physicochemical composition (Nardone et al, 2010;Salari et al, 2016;Clark and García, 2017). In this study, the flock was housed in 1-sided sheds and fed a TMR year-round.…”

Keep Garfagnina alive. An integrated study on patterns of homozygosity, genomic inbreeding, admixture and breed traceability of the Italian Garfagnina goat breed

“…This, in turn, resulted in breed traceability with a 100% success rate after CV. To sum up, our analysis complements previous work on various zootechnical and adaptive characteristics [4,7,8] of the GRF population and provides with a more complete description of the breed.…”

“…PCA and admixture analysis were used to infer the presence of distinct populations based on the genomic data. The proportion of mixed ancestry in the breeds was assessed by the ADMIXTURE 1.22 software [7, 8]. The number of ancestries (K) to be retained in the admixture analysis (K = 2 to 10) was evaluated via a 10-fold cross-validation (CV).…”

“…To support the management and conservation of the breed, and to provide support to the farmers and to the general region where the breed is reared (hills and mountains of the northwestern Tuscan Apennine area - central Italy), a few studies investigated various production characteristics [4,7], the adaptive profile (through physiological, haematological, biochemical and hormonal parameters) [8] and resistance to diseases [9,10] of GRF. Martini et al [4] investigated various zootechnical characteristics of the GRF breed in comparison to other Italian and foreign goat breeds.…”