The Design of a New Catheter for Transcervical Artificial Insemination in Ewes.

In ovine species, transcervical artificial insemination (TCAI) is limited by the poor quality of frozen-thawed semen and by the convoluted cervical lumen hampering the passage of inseminating devices. The aim of the study was to test the efficiency of three newly designed catheters with bent tips of 3.5 mm, 5.0 mm or 8.0 mm in terms of reproductive performances (experiment 1) and to compare the results of TCAI with the best performing catheter of experiment 1 to those obtained in ewes submitted to surgical incision of cervical folds (SICF) prior to insemination (experiment 2). The following parameters were assessed: time to pass the cervix; depth of cervical penetration; site of deposition of semen; pregnancy (PR); and lambing rates (LR). The results of experiment 1 indicated that the 5.0 mm tip catheter resulted in deeper and faster TCAI and higher PR and LR compared to 3.5 mm and 8.0 mm tip catheters (p < 0.05). In experiment 2, TCAI with the 5.0 mm catheter did not differ from TCAI after SICF in terms of depth of semen deposition, time to pass the cervix, PR and LR (p < 0.05). In conclusion, the use of a catheter that allowed transcervical uterine deposition of semen without excessive manipulation led to satisfactory pregnancy rates.

Effect of Suckling Management and Ewe Concentrate Level on Methane-Related Carbon Footprint of Lamb Meat in Sardinian Dairy Sheep Farming.

The aim of this study was to estimate the methane-linked carbon footprint (CF) of the suckling lamb meat of Mediterranean dairy sheep. Ninety-six Sarda dairy ewes, divided into four groups of 24 animals each, were assigned to 2 × 2 factorial design. The experiment included the suckling lamb feeding system: traditional (TS), in which lambs followed their mothers on pasture during grazing time, vs. separated (SS), in which lambs remained indoors, separated from their mothers during the grazing time. Each group was divided into high (HS) and low (LS) supplemented ewes (600 g/d vs. 200 g/d of concentrate). The estimated CH4 emission of the ewes, calculated per kg of body weight (BW) gain of the lamb during the suckling period, was then converted to CO2eq with multiplying factor of 25. The TS lambs showed lower methane-linked emissions than SS ones (p < 0.05). The sex of lambs affected their methane-linked CF, with males having lower (p < 0.05) values than females. Twins displayed much lower methane-linked CF than singles (4.56 vs. 7.30 kg of CO2eq per kg of BW gained), whereas the level of supplementation did not affect greenhouse gases (GHG) emission. Interaction displayed lower and not-different GHG emissions for both indoor- and outdoor-reared twins. In conclusion, the methane-linked CF of the suckling lamb meat can be reduced by maintaining the traditional lamb rearing system and by improving flock prolificacy.

Effect of Dams and Suckling Lamb Feeding Systems on the Fatty Acid Composition of Suckling Lamb Meat.

The effects of the dams and suckling lamb feeding systems on the fatty acid (FA) profile of lamb meat are reviewed in this article. The suckling lamb can be considered a functional monogastric, and therefore, its meat FA composition is strongly influenced by the FA composition of maternal milk. The major source of variation for ewe milk FA composition is represented by pasture amount and type. In the traditional sheep breeding system of the Mediterranean area, the main lambing period occurs in late autumn-early winter, and ewes are able to exploit the seasonal availability of the natural pastures at their best. Therefore, lambs start suckling when maternal milk concentrations of vaccenic, rumenic, and n-3 long-chain polyunsaturated FA in maternal milk are the highest. When maternal diet is mainly based on hay and concentrates, the use of vegetable oils can be considered a good strategy to improve the meat FA profile of suckling lambs.