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AIM: The anterior cervical presternocleidomastoid approach is a safe and standardized procedure. Nevertheless, in all the largest series presented in literature, a certain risk of injury to the recurrent laryngeal nerves (RLNs) is reported and the choice of the side of the approach seems to influence such risk. Our aim was to study the surgical anatomy of the RLNs and to understand whether the side of the approach can be a risk factor for their surgical damage. METHODS: We performed an anatomical dissection of 6 fresh cadavers, studying the origin and the course of both the RLNs, to assess their vulnerability in the anterior presternocleidomastoid approach to the cervical spine. RESULTS: The origin of the right RLN was at C7 in 2 cases and at T1 in 4 cases. In all cases it arose where vagus nerve crossed the subclavian artery and it was directed superiorly and transversely to the esophagotracheal groove. CONCLUSIONS: The right and left RLNs have different origin and course. Although the discussion about the best side for the anterior cervical approach is debated, in our opinion, both anatomical and surgical considerations, concerning RLNs, lead to the evidences that the left side approach, when possible, should be preferred below the level of C4.

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The cervico-thoracic junction (CTJ) extends between the 7th cervical and the 4th thoracic vertebrae and comprehends the inferior portion of the brachial plexus and the parenchymatous, vascular and nervous structures of the upper mediastinum. The posterior surgical approaches, as the laminectomy or the arthro-pediclectomy, fail to expose the anterior spinal elements. Thus, further surgical approaches have been proposed: postero-lateral, antero-lateral (thoracotomies) and purely anterior. The aim of this study was to discuss indications, key anatomical landmarks and risks of the main surgical approaches to the CTJ. Ten fresh cadavers from the Anatomical Laboratory of the University of Nantes (France) were used for the surgical dissection of the CTJ. The postero-lateral and the antero-lateral approaches were performed in 4 cadavers each and the anterior approaches were studied in 2. The postero-lateral extrapleural approach (PLEA) permits an excellent antero-lateral exposure of the T2-T4 segment, preserving the parascapular musculature integrity. The thoracotomies allow the exposure of the antero-lateral portion of the junctional vertebrae, with the limits of the intrapleural approaches. The anterior approaches, including the presternocleidomastoid cervicotomy eventually associated to the sterno-claviculotomy, expose the anterior portion of the cervical and the upper thoracic vertebrae up to T4. We believe that the PLEA performs the greater surgical exposure with minimal risk of vasculo-nervous damage. Among the anterior approaches, the simple cervicotomy is the most indicated procedure in case of patients with certain anatomical conditions.

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Two groups of 20 early-lactating Comisana ewes were used in this study, and were allocated to either an indoor or outdoor daytime environment. The indoor environment was a 3mx12m straw bedded pen inside a pre-fabricated building. The outdoor environment was a 200m(2) paddock during daytime (09.00-19.00h) with ewes being moved to the shed, as described for the indoor treatment, at night. Behavior of ewes was recorded at 14 days interval from 09.00 to 19.00h. A phytohemagglutinin (PHA) skin test was performed at weeks 6, 11, 15 and 18 of the experiment to induce a non-specific delayed-type hypersensitivity in ewes. Jugular blood samples were taken at the beginning and at weeks 5, 10, 14 and 18 to determine endocrine and metabolic responses of animals to housing system and to changes in climatic conditions and stage of lactation. Ewe milk yield was recorded daily and individual milk samples were analyzed for milk composition, coagulating properties and somatic cell count (SCC) at 14 days interval. No differences were found between groups for endocrine and immune responses. Outdoor ewes had increased locomotor activities (P<0.01) and decreased idling (P<0.05) compared to indoor animals. The outdoor group had higher levels of blood creatinine (P<0.01) and inorganic phosphorus (P<0.05) as well as lower urea (P<0.01) and glucose (P<0.001) concentrations compared to the indoor group. Milk yield and composition were not changed by the housing system, though significant timextreatment interactions were found for milk constituents, with indoor-housed ewes having higher (P<0.05) milk protein, fat and lactose concentrations during the middle of the trial. Outdoor ewes had lower SCC (P<0.003) and pH (P<0.001) in their milk than indoor ewes, whereas renneting parameters were not different across treatments. Results suggest that ewe welfare and productivity were not substantially affected by the housing system. The provision of feeding rations that meet the greater energy demand for maintenance is required to sustain productivity in outdoor reared sheep.

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A study was conducted to investigate the effects of prefreezing sperm concentration using two extenders on post-thaw survival and acrosomal status of ram spermatozoa (Experiment 1) and fertility after intrauterine insemination with differing doses of semen (Experiment 2). In autumn (Northern hemisphere), semen was collected by artificial vagina from 8 adult Leccese rams and ejaculates of good quality semen were pooled. Two extender systems for cryopreservation were considered, one based on milk-lactose egg yolk (Milk-LY) and the other based on tris-fructose egg yolk (Tris-FY). Experiment 1 (2 x 6 factorial scheme) examined the in vitro characteristics of spermatozoa in relation to the Milk-LY and Tris-FY extenders and six prefreezing sperm concentrations (50, 100, 200, 400, 500 and 800 x 10(6) spermatozoa/mL). Experiment 2 (2 x 4 factorial) evaluated the influence of the Milk-LY vs Tris-FY extenders and four doses (20, 40, 80 and 160 x 10(6) spermatozoa/0.25 mL) corresponding to prefreezing spermatozoa concentrations of 100, 200, 400 and 800 x 10(6) spermatozoa/mL, on fertility of ewes inseminated in uterus by laparoscope. Prefreezing sperm concentration influenced (P < 0.01) freezability of spermatozoa and affected negatively all the in vitro parameters at 800 x 10(6) spermatozoa/mL. Overall, Milk-LY tended to ensure higher viability and acrosomal integrity of spermatozoa after thawing at the intermediate sperm densities (range 100 to 500 x 10(6) spermatozoa/mL). At 500 x 10(6) spermatozoa/mL concentration corresponded the best condition for survival of spermatozoa (71.2%), acrosome integrity (71.5%) and acrosomal loss (6.0%). At the lowest sperm concentration (50 x 10(6) spermatozoa/mL), Tris-FY resulted in a higher survival rate than Milk-LY (61.3%, P < 0.05) and lower acrosomal loss (9.7%, P < 0.05). Milk-LY supported spermatozoa motility better than Tris-FY after incubation at sperm concentration between 50 and 400 x 10(6) spermatozoa/mL (0.05 > P < 0.01). Semen doses of 20 to 40 x 10(6) spermatozoa/ewe provided satisfactory fertility rates (64 to 81%). The increase of inseminate doses to 160 x 10(6) spermatozoa/ewe failed to improve fertility, actually tending to decrease lambing rates.

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Three experiments were carried out to evaluate induction in ewes of superovulation and embryo production by a single injection of a porcine pituitary extract (pFSH) dissolved in polyvinylpyrrolidone (PVP), investigating the effects of PVP molecular weight and its concentration (Experiment I), time and method of treatment (Experiments II and III). All ewes were synchronized for estrus by vaginal sponges impregnated with fluorogestone acetate (FGA; 30 mg, 9 days) plus PGF(2alpha) (Cloprostenol, 50 microg, 48h before sponge removal - s.r.), and superovulated by 250 IU pFSH. In Experiment I, 60 Gentile di Puglia ewes were subdivided into five experimental groups (n = 12): Group A, the control, received six decreasing intramuscular (i.m.) doses of pFSH, 12 h apart, beginning 48h before s.r.; Groups B and C were given 48 h before s.r. a single i.m. injection of pFSH dissolved in PVP with MW = 10,000, respectively, at concentrations of 15 and 30% w/v; Groups D and E received the same treatments as for B and C using PVP with MW = 40,000. None of the pFSH-PVP treatments were effective in inducing superovulation. In Experiment II, 22 Leccese ewes were subdivided into two groups (n = 11): Group A, control received i.m. four decreasing doses of pFSH, beginning 24 h before s.r., 12h apart; Group B was given a single i.m. injection of pFSH dissolved in PVP (MW = 40,000 at 30% w/v), 24 h before s.r. The pFSH-PVP treatment provided an ovulation rate similar to the control and tended to enhance embryo yield (4.4 versus 2.4, P>0.05). In Experiment III, 60 Leccese ewes were subdivided into six treatment groups (n = 10). Groups A and D served as controls and received i.m. 12 h apart, six doses (from 48 h before s.r.) and four doses (from 24h before s.r.) of pFSH, respectively. Groups B and C were treated by a single injection of pFSH in PVP (MW = 10,000; 30% w/v) 48 h before s.r., respectively by i.m. or subcutaneous (s.c.) administration. Groups E and F received the same treatments as for B and C 24 h before s.r. Intramuscular pFSH-PVP administration 24 h before s.r. provided an ovulation rate (8.1), mean numbers of ova recovered (5.6) and fertilized (4.2) comparable to the six or four dose treatments and significantly higher (P <0.01) compared to the pFSH-PVP treatment carried out i.m. 48 h before s.r. These results show that a single injection of pFSH dissolved in PVP at 30% w/v, performed i.m. 24 h before s.r., is able to induce a superovulatory response comparable to that following multiple injection treatment, regardless of PVP molecular weight.

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Growth performance, ossification of metacarpal growth plate, and intra-muscular collagen characteristics in three muscles of 10 intact male Garganica kids were studied. Each week, starting from the 47th day of age to slaughter (75th day of age), kids were weighed and blood samples taken for plasma non-protein hydroxyproline analysis. At slaughter, metacarpal, metatarsal bones and metacarpal growth plate thickness were measured. The semitendinosus (ST), semimembranosus (SM), and rectus medialis (RM) muscle samples were analysed for collagen concentration and hydroxylysyl pyridinoline (HP) cross-links. ST muscle had a collagen amount higher than SM and RM (P<0.01), and RM muscle had the highest (P<0.01) HP concentration. Tenderness index was the highest (P<0.01) in RM muscle. Animal growth rates slowed, starting from 61st day of age (P<0.01); this trend coincided with a marked reduction in concentration of plasma non-protein hydroxyproline (P<0.01). In addition, plasma non-protein hydroxyproline concentration was positively correlated (r=0.61, P=0.001) with growth rate of animals, suggesting that collagen turnover decreases during a slow growth phase. Based on the metacarpal growth plate width, the rate of bone ossification appears to be slower in goats than sheep.