The effect of parity number on the metabolism, inflammation, and oxidative status of dairy sheep during the transition period.

The objective of this study was to evaluate whether dairy sheep during the transition period are affected by their parity numbers with regard to (1) body weight (BW), body condition score (BCS), and production performance (milk yield and composition) and (2) metabolic, inflammation, and stress biomarkers. For this purpose, 30 Sarda dairy ewes [15 primiparous (PRP) and 15 multiparous (MUP) ewes] were recruited on d 90 of gestation. Each group was homogeneous according to age, BW, and BCS. Sampling was carried out at -60, -30, -7, 0, +30, and +60 d from lambing. The MUP ewes showed a higher BW (46.32 vs. 38.71 kg) and larger litter size (1.45 vs. 1.06 kg) but a lower BCS (2.47 vs. 2.70) than the PRP ewes. Furthermore, the MUP ewes had lower concentrations of glucose (3.49 vs. 4.27 mol/L), cholesterol (1.63 vs. 1.81 mmol/L), free fatty acids (0.47 vs. 0.62 mmol/L), and triglycerides (0.22 vs. 0.25 mmol/L) compared with PRP ewes. With regard to inflammation and oxidative stress parameters, the PRP group had higher haptoglobin (0.48 vs. 0.18 g/L) and paraoxonase (187.90 vs. 152.11 U/L) activity than the MUP group. Overall, the MUP ewes were characterized by greater milk production performance and greater feed intake, resulting in a better energy balance, than the PRP ewes. Interestingly, these findings highlighted a different metabolic and inflammatory response over the transition period between PRP and MUP ewes, with the latter displaying lower concentrations of inflammatory-related biomarkers

Applicability of Day O superovulation protocol in Boer goats

This study evaluated the applicability of the Day 0 superovulation protocol in Boer goats by comparing it to a traditional pFSH protocol. Twenty Boer goat does were allocated into two groups comprising of 10 animals per group. For the Day 0 protocol, does oestrous cycles were synchronized for 9 days and superovulated with pFSH starting 84 h after the termination of progesterone treatment. For the traditional pFSH protocol, the oestrous cycle of does was synchronized for 9 days, followed by superovulation with pFSH initiated 48 h before CIDR withdrawal. For both groups does had two timed cervical inseminations with fresh undiluted semen. Embryos from both groups were flushed on day 6 following AI. The response to superovulation did not differ significantly between treatments but a tendency (P = 0.06) was found for both fertilization and number of unfertilized ova in favour of the Day 0 protocol. The number of follicles 2–3 mm, 4–5 mm and total number offollicles atthe beginning of a superovulation treatment was positively correlated to the total number of structures and embryos recovered. It is therefore concluded that the Day 0 protocol can be used for superovulation in Boer goat does however, more studies with large number of animals are recommended to ascertain its benefits. The correlation results suggest that the response to superovulation and quality of embryos recovered could be more determine by the size and number of follicles at the beginning of a superovulation treatment.The National Research Foundation and the Tshwane University of Technology.http://www.elsevier.com/locate/smallrumres2017-03-31hb2017Animal and Wildlife Science

Transplantation of sheep embrionic stem cells in cartilage lesions: preliminary observations

The aim of this study is to evaluate whether ovine embryonic stem cells transplanted in experimental lesions can differentiate into chondrocyte cells and if the new cartilage is of ialine type

Does the timing of pasture allocation affect rumen and plasma metabolites and ghrelin, insulin and cortisol profile in dairy ewes?

A study was undertaken to assess the impact of the timing of grazing on rumen and plasma metabolites and some metabolic hormones in lactating dairy sheep allocated to an Italian ryegrass (Lolium multiflorum Lam) pasture in spring for 4 h/d. Twenty-four mid lactation Sarda ewes stratified for milk yield, body weight, and body condition score, were divided into four homogeneous groups randomly allocated to the treatments (2 replicate groups per treatment). Treatments were morning (AM, from 08:00 to 12:00) and afternoon pasture allocation (PM, from 15:30 to 19:30). Samples of rumen liquor (day 39) and blood plasma (days 17 and 34 of the experimental period) were collected before and after the grazing sessions. Moreover, on days 11 and 35, grazing time was assessed by direct observation and herbage intake measured by the double weighing procedure. Grazing time was longer in PM than AM ewes (P < 0.001) but herbage intake was undifferentiated between groups. The intake of water-soluble carbohydrates at pasture was higher in PM than AM ewes (P < 0.05). The post-grazing propionic and butyric acid concentration, as measured on day 39, were higher in PM than AM ewes (P < 0.05). The basal level of glucose on day 34 and insulin (on both sampling days) were higher in PM than AM (P < 0.05). The opposite trend was detected for non-esterified fatty acids (P < 0.05, day 34) and urea (both days). Pasture allocation in the afternoon rather than in the morning decreased plasma concentration of ghrelin (P < 0.001) and cortisol (P < 0.001), with a smoothed trend on day 34 in the latter variable. To conclude, postponing the pasture allocation to afternoon increased the intake of WSC, favoring a glucogenic pattern of rumen fermentation and a rise of glucose and insulin levels in blood, although these effects were not consistent across the whole experimental period. Moreover, the afternoon grazing decreased the level of cortisol and ghrelin, suggesting a higher satiation-relaxing effect

Reprogramming of Sheep Fibroblasts into Pluripotency under a Drug-Inducible Expression of Mouse-Derived Defined Factors

Animal embryonic stem cells (ESCs) provide powerful tool for studies of early embryonic development, gene targeting, cloning, and regenerative medicine. However, the majority of attempts to establish ESC lines from large animals, especially ungulate mammals have failed. Recently, another type of pluripotent stem cells, known as induced pluripotent stem cells (iPSCs), have been successfully generated from mouse, human, monkey, rat and pig. In this study we show sheep fibroblasts can be reprogrammed to pluripotency by defined factors using a drug-inducible system. Sheep iPSCs derived in this fashion have a normal karyotype, exhibit morphological features similar to those of human ESCs and express AP, Oct4, Sox2, Nanog and the cell surface marker SSEA-4. Pluripotency of these cells was further confirmed by embryoid body (EB) and teratoma formation assays which generated derivatives of all three germ layers. Our results also show that the substitution of knockout serum replacement (KSR) with fetal bovine serum in culture improves the reprogramming efficiency of sheep iPSCs. Generation of sheep iPSCs places sheep on the front lines of large animal preclinical trials and experiments involving modification of animal genomes

Circulating Concentrations of Key Regulators of Nitric Oxide Production in Undernourished Sheep Carrying Single and Multiple Fetuses

15 Pág.The aim of this study was to investigate the blood concentrations of L-arginine, asymmetric dimethylarginine (ADMA), symmetric dimethylarginine (SDMA), and L-homoarginine, which are regulators of nitric oxide (NO) synthesis, in single, twin, and triplet pregnancies in ewes undergoing either a dietary energy restriction or receiving 100% of their energy requirements. From day 24 to 100 of pregnancy, the ewes were fed ryegrass hay and two different iso-proteic concentrates fulfilling either 100% of ewes' energy requirements (control group; n = 30, 14 singleton pregnancies, 12 twin pregnancies, and 4 triplet pregnancies) or only 45% (feed-restricted group; n = 29; 11 singleton pregnancies, 15 twin pregnancies, and 3 triplet pregnancies). Blood samples were collected monthly to measure, by capillary electrophoresis, the circulating concentrations of arginine, ADMA, homoarginine, SDMA, and of other amino acids not involved in NO synthesis to rule out possible direct effects of diet restriction on their concentrations. No differences between groups were observed in the circulating concentrations of most of the amino acids investigated. L-homoarginine increased markedly in both groups during pregnancy (p < 0.001). SDMA (p < 0.01), L-arginine, and ADMA concentrations were higher in feed-restricted ewes than in controls. The L-arginine/ADMA ratio, an indicator of NO production by NOS, decreased towards term without differences between groups. The ADMA/SDMA ratio, an index of the ADMA degrading enzyme activity, was higher in controls than in feed-restricted ewes (p < 0.001). Obtained results show that circulating concentrations of L-arginine, of its metabolites, and the ratio between NO synthesis boosters and inhibitors are altered in energy-restricted ewes, and that these alterations are more marked in ewes carrying multiple fetuses.The experimental work was supported by funds from Regione Autonoma della Sardegna—Progetti ricerca fondamentale o di base—L.R. 7/2007—annualità 2013 (CRP 78167).Peer reviewe

Organic breeding in Sarda ewes: Utilization of the ram effect in an artificial insemination program

The current study assesses the ram effect as an alternative to conventional hormonal treatment for estrus synchronization prior to artificial insemination. Two groups of 50 anoestrus Sarda ewes were induced to ovulate with adult rams (RE group) or synchronized using intravaginal sponges impregnated with progestogen and equine chorionic gonadotropin (eCG) (PRO group). Ewes in the RE group were isolated from rams for 6 weeks. After the isolation period, 5 vasectomized rams were introduced into the flock at a ratio of 1 ram/10 females (day 0) to induce estrus and ovulation. Ewes in both experimental groups were inseminated via the cervical route with fresh semen (400 million spermatozoa/0.25 ml) 24 h after the onset of estrus (day 15–24). The pregnancy rate, assessed by ultrasound 35 days after insemination, was 48.9% (24/49) and 43.47% (22/50) for sheep in RE and PRO groups respectively. Lambing rates were identical to pregnancy rates in both groups, while the prolificacy rate was 120% (59/49) and 130% (65/50) in RE and PRO groups respectively. No significant differences were found between the 2 groups. The data supports the conclusion that the ram effect can be used successfully to synchronize estrus in organic farming operations. © 2019 Elsevier B.V.Agricultural Research Development AgencyThe authors address their thanks to the Agricultural Research Agency of Sardinia, Department of Animal Science (Agris-Sardegna, DIRPA) for financial support. At the same time the authors thank Dr. Debbie Gillette, veterinary pathologist for critical reading and english editing