Cristina Giosue

Jennet milk production during the lactation in a Sicilian farming system.

In Italy, the interest for jennet milk production has recently developed. An 18-month-long experiment was carried out on a jennet farm near Milo (CT), where 24 jennets, which derived from the Ragusana breed, were tested for milk yield and composition over an entire lactation period. The jennets were fed with hay and concentrate in a large paddock. From the 28th post-foaling day to the end of the lactation, the jennets were machine-milked twice a day with an in-between milking interval of 5 h. The milk amount from each jennet was recorded every 3 weeks and individual samples were collected and analyzed for fat, protein, casein, non-proteic nitrogen, lactose and somatic cell count. This study showed that jennets at Sicilian latitudes are not seasonal polyestrous. The daily milk yield, the length of lactation and the milk characteristics varied depending on the foaling season. The total average milk production was 490 ± 36 kg in 295 ± 12 post-foaling days, considering two milking records per day. During the lactation, milk yield decreased constantly from 1.98 to 1.28 kg/jennet per day. When looking at the jennet milk quality during lactation, the percentage of fat and protein decreased, while the lactose percentage increased, according to a tendency apparently unique for equines when compared to the ruminants. When looking at the productive season, spring generally gave the best qualitative and quantitative results. Based on these results, jennet milk yield and quality could be improved; furthermore, jennet milk production may turn out to be a profitable business.

Valorization of indigenous dairy cattle breed through salami production

The aim of the research was to produce salami manufactured with meat of three different commercial categories of bovine breed: cow on retirement, beef and young bull. A total of six experimental productions, at small-scale plant, were carried out with and without starter culture inoculums. The evolution of physico-chemical parameters in all trials followed the trend already registered for other fermented meat products. Several LAB species were found during process with different levels of species diversity and frequency of isolation among inoculated (mainly Pediococcus pentosaceus and Staphylococcus xylosus) and uninoculated (mainly Enterococcus devriesei, Lactobacillus curvatus and Lactobacillus sakei) trials. Enterobacteriaceae were found at very low levels during the entire ripening period and no pathogenic bacteria were found in any samples. The multivariate analysis showed that starter inoculums and meat affected significantly the physico-chemical and the microbiological composition of salami. The sensory analysis evidenced the highest overall acceptability was displayed by salami produced with meat from cow on retirement.

Effects of ewes grazing sulla or ryegrass pasture for different daily durations on forage intake, milk production and fatty acid composition of cheese.

Sulla (Sulla coronarium L.) forage is valued for its positive impact on ruminant production, in part due to its moderate content of condensed tannin (CT). The duration of daily grazing is a factor affecting the feed intake and milk production of ewes. In this study, the effects of grazing sulla pasture compared with annual ryegrass, and the extension of grazing from 8 to 22 h/day, were evaluated with regard to ewe forage intake and milk production, as well as the physicochemical properties and fatty acid (FA) composition of cheese. During 42 days in the spring, 28 ewes of the Comisana breed were divided into four groups (S8, S22, R8 and R22) that grazed sulla (S) or ryegrass (R) for 8 (0800 to 1600 h) or 22 h/day, and received no feeding supplement. In six cheese-making sessions, cheeses were manufactured from the 48 h bulk milk of each group. Compared with ewes grazing ryegrass, those grazing sulla had higher dry matter (DM) intake, intake rate and milk yield, and produced milk that was lower in fat and higher in casein. Ewes grazing for 22 h spent more time eating, which reduced the intake rate, increased DM and nutrient intake and milk yield, and reduced milk fat. Due to the ability of CT to inhibit the complete ruminal biohydrogenation of polyunsaturated fatty acids (PUFA), the FA composition of sulla cheese was more beneficial for consumer health compared with ryegrass cheese, having lower levels of saturated fatty acids and higher levels of PUFA and n-3 FA. The FA profile of S8 cheese was better than that of S22 cheese, as it was higher in branched-chain FA, monounsaturated FA, PUFA, rumenic acid (c9,t11-C18:2), and had a greater health-promoting index. The effect of short grazing time on sulla was attributed to major inhibition of PUFA biohydrogenating ruminal bacteria, presumably stimulated by the higher accumulation of sulla CT in the rumen, which is related to a higher intake rate over a shorter eating time. Thus, grazing sulla improved the performance of ewes, thereby increasing, especially with short grazing time, the nutritional properties of cheese fat.

Effects of foal presence at milking and dietary extra virgin olive oil on jennet milk fatty acids profile

Abstract Twelve Ragusana jennets were studied to investigate the effects of dietary extra virgin olive oil and presence of the foal during milking on milk fatty acids (FA) profile. At 20, 50 the and 90 days post-foaling, each jennet was milked 4 times per day. The feeding system and the milking procedures are given by Alabiso et al. (2009). FA profiles of the composites from milkings without foals (1MNF+3MNF) and with foals (2MYF+4MYF) were analyzed by gas chromatography. Dietary oil had no significant effect on milk yield or fat content but increased the proportion of C18:1 (n-9) in milk. Jennet milk had a beneficial FA profile compared to bovine milk and thus would be suitable for consumption by infants suffering from cows milk protein allergy, however, augmentation of the long-chain n-3 polyunsaturated FA content warrants further study.

Legume grain-based supplements in dairy sheep diet: Effects on milk yield, composition and fatty acid profile

With the aim to find protein sources that are free of genetically modified organisms, the effects of legume grain-based concentrates, used as alternatives of a mixed concentrate feed containing soybean, were evaluated on sheep milk production. Twelve lactating ewes were divided into four groups, fed hay and, according to a 4 × 4 Latin square design, supplied with 800 g/day of a commercial mixed concentrate feed (MCF) containing maize and soybean, or the same amount of isoprotein concentrates consisting of chickpea (CH), faba bean (FB), or pea (PE) mixed with barley. The ewes ingested more of the concentrates with legume grains than the MCF (702, 702, 678 vs 587 g/day DM for CH, FB, PE and MCF; P ≤ 0.001). Compared with CH, FB and PE resulted in greater (P ≤ 0.05) milk yield (710, 718 vs 654 g/day for FB, PE and CH, respectively), and led to a greater (P ≤ 0.05) efficiency of dietary protein utilisation for milk casein synthesis (94, 97 vs 87 g casein/kg crude protein intake for FB, PE and CH, respectively), whereas MCF resulted in intermediate levels of milk yield (677 g/day) and milk casein/crude protein intake (88 g/kg). Chickpea increased the milk content of trans-vaccenic and rumenic acids in comparison with FB and PE and, similarly to MCF, increased the milk content of linoleic acid, as well as total unsaturated fatty acids (24.3, 23.9 vs 17.2, 16.8 g/100 g fatty acid methyl esters for MCF, CH, FB and PE; P ≤ 0.001), thereby improving the potential health-promoting index. Legume grains can replace soybean in diets of dairy ewes, as they do not adversely affect milk yield and composition.

Effects of the foal at the milking and dietary supplementation with extra virgin olive oil on jennet milk production

Abstract The effects of the foal at the milking and the extra virgin olive oil supplementation in the diet, on the milk obtained by 12 Ragusana jennets were studied. The jennets were each fed 3.5+1.5 kg/d of concentrate+bran, and hay ad libitum. They were divided into 2 equal groups with one group receiving an additional dietary supplement of 100 ml/d of olive oil. Milk was collected at day 20 post foaling and every 15-18 d for 5 times. At each collection period jennets were milked 4-times per day. At 07:30 h foals were separated from the jennets and after a 4 hour interval were milked manually (1MNF;1st milking, foal absent). At the end of the 1MNF, each jennet was milked again, with the foals kept near the udder, but prevented from suckling (2MYF; 2nd milking, foal present). After 2MYF, foals were removed a second time and the sequence repeated after another 4 hour interval for the 3rd (3MNF) and 4th (4MYF) milkings. Milk yield was recorded at each milking and samples analyzed for qualitative variables. The milk yield was 26% higher than that reported by Giosuè et al. (2008) in similar conditions. The milk fat content were positively influenced by the presence of the foal at the milking but was not effect by the dietary supplement of olive oil.