189 research outputs found

    Highly precocious activation of reproductive function in autumn-born goats (Capra hircus) by exposure to sexually active bucks

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    Goats are seasonal breeders with the main cue controlling the timing of breeding season being photoperiod. Hence, the season of birth impacts puberty onset: spring-born goats reach puberty in autumn, at 7 mo of age, whereas autumn-born goats reach puberty at 1 yr during the next reproductive season. The aim of this study was to determine whether exposure of autumn-born young females to sexually active males could counteract the delay in puberty onset observed in autumn-born goats. Females exposed to sexually active males (n = 8) reached puberty earlier than isolated females (n = 8), with exposed females ovulating at a mean age of 3.5 mo. To our knowledge, such precocious puberty onset obtained through social stimulation has never been described in the literature. Moreover, those exposed females exhibited estrus behavior for most ovulations. Our results indicate that in goats born out of season, exposure to sexually active bucks is a really efficient approach to induce early puberty, suggesting that social interactions could have a crucial impact on the regulation of pubertal transition

    The continuous presence of ewes in estrus in spring influences testicular volume, testicular echogenicity and testosterone concentration, but not LH pulsatility in rams

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    The continuous presence of active male small ruminants prevents seasonal anestrus in females, but evidence of the same mechanism operating from the females to the males is scarce. This study assessed the effects of the continuous presence of ewes in estrus in spring on ram sexual activity, testicular size and echogenicity, and LH and testosterone concentrations. On 1 March, 20 rams were assigned to two groups (n = 10 each): isolated (ISO) from other sheep, or stimulated (STI) by 12 ewes, which were separated from the rams by an openwork metal barrier, allowing contact between sexes. Each week, four ewes were induced into estrus by intravaginal sponges. Live weight, scrotal circumference, testicular width (TW) and length (TL) were recorded at the beginning and at the end of the experiment, and testicular volume (TV) was calculated; at the same time, testicular ultrasonography and color Doppler scanning were performed. Blood samples (March to May) were collected once per week for testosterone determinations, and at the end of the experiment, blood samples were collected for 6 h at 20-min intervals for LH analysis. Rams were exposed to four estrous ewes in a serving-capacity test. Scrotal circumference, TW and TL were higher in the STI than in the ISO rams (P < 0.05) in May, and TV was higher (P < 0.05) in the STI (391 ± 17 cm3) than in the ISO rams (354 ± 24 cm3). In ISO rams, the number of white pixels was higher (P < 0.01) in May (348 ± 74) than in March (94 ± 21) and differed significantly (P < 0.01) from that of the STI rams in May (160 ± 33). In ISO rams, the number of grey pixels was higher (P < 0.05) in May (107 ± 3) than it was in March (99 ± 1). Stimulated and ISO rams did not differ significantly in mean LH plasma concentrations (0.8 ± 0.5 v. 0.9 ± 0.4 ng/ml), LH pulses (2.1 ± 0.5 v. 2.2 ± 0.2) and amplitude (2.0 ± 0.4 v. 3.2 ± 0.7 ng/ml, respectively). Stimulated rams had significantly higher testosterone concentrations than ISO rams from April to the end of the experiment. Stimulated rams performed more (P < 0.05) mountings with intromission (3.0 ± 0.4) than did ISO rams (1.5 ± 0.5). In conclusion, after 3 months in the continuous presence of ewes in estrus in spring, rams had higher TV and some testicular echogenic parameters were modified than isolated rams. Although exposed rams also had higher levels of testosterone after 2 months in the presence of estrous ewes, their LH pulsatility at the end of the study was not modified

    Exposure to Photoperiod-Melatonin-Induced, Sexually-Activated Rams after Weaning Advances the Resumption of Sexual Activity in Post-Partum Mediterranean Ewes Lambing in January

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    This study was aimed to determine whether the presence of sexually stimulated rams by photoperiodic and melatonin treatments can advance the resumption of post-partum sexual activity in Mediterranean ewes lambing in January and weaned at the end of the breeding season at 41°N, in March. Rams were exposed to two months of long days (16 h light/day) and given three melatonin implants at the end of the long days (sexually-activated rams; SAR). Control rams (CR) were exposed to the natural photoperiod. Thirty-six ewes weaned on 25 February were assigned to one of two groups. From 1 March to 30 June, one group was housed with four SAR males (SAR-treated; n = 18), and the other group (CR-treated; n = 18) was housed with four unstimulated rams. Ovulation was assessed once per week based on plasma progesterone concentrations. Estrus was monitored daily by marks left on ewes by rams’ harnesses. SAR-treated ewes had a shorter (p < 0.01) weaning–first estrus interval than CR-treated ewes (61 ± 17 days vs. 102 ± 47 days; mean date of first estrus after weaning on April 26 and June 6, respectively). The proportion of the ewes ovulating in April or May was higher (p < 0.05) in the SAR-treated group than in the CR-treated group. SAR-treated ewes resumed estrous activity sooner than CR-treated ewes such that, in April, May, and June, the proportion of females that exhibited estrus was higher (p < 0.01) in the SAR-treated group (72%, 89%, and 100%, respectively) than in the CR-treated group (17%, 44%, and 61%, respectively). In conclusion, the introduction at weaning of sexually activated rams advanced the resumption of estrous activity in ewes in spring. The practical implications of this work could be important in ewes adapted for intensive production and accelerated lambing systems

    Shelf-life extension of watermelon juice preserved by hyperbaric storage at room temperature compared to refrigeration

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    This work reports Hyperbaric Storage (HS) preservation of raw watermelon juice at variable/uncontrolled room temperature (RT,z21 C) for 7 days at 100 MPa and compared it with refrigeration (RF). At the end of storage, there was an increase in microbial counts (total aerobic mesophiles, psychrophiles, and yeasts and moulds) to above 6 log10 CFU/mL for samples stored at atmospheric pressure (RF and RT), while juice stored under HS/RT showed maximum values of about 2 log10 CFU/mL for total aerobic mesophiles/ psychrophiles and below the detection limit for yeasts and moulds. HS/RT juice showed also physicochemical parameters at levels similar to the initial juice. Thus, HS/RT can not only be used to preserve foods with no refrigeration energetic costs (since it does not require temperature control), but additionally, has also a great potential to extend the shelf-life of food products, compared to RF. This is the first case in the literature showing this additional potential/advantage of HS/RT

    High pressure and thermal pasteurization effects on sweet cherry juice microbiological stability and physicochemical properties

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    This study evaluated high pressure processing (P1 – 400 MPa/5 min; P2 – 550 MPa/2 min) and thermal pasteurization (TP – 70°C/30 s) effects on sweet cherry juice’s microbiological and physicochemical parameters, during four weeks of refrigerated storage. All treatments reduced the microbiological load to undetectable levels not affecting total soluble solids and titratable acidity. The pH increased with all treatments, however, it decreased during storage. Phenols were differently affected: TP increased them by 6%, P1 had no effect while P2 decreased them by 11%. During storage, phenols in control and TP samples decreased by 26% and 20%, P1 samples decreased them by 11% whereas P2 showed no variation. TP had no effect on anthocyanins, while pressure treatments increased them by 8%. Anthocyanins decreased during storage, particularly in the control and P1 (decreasing 41%). All treatments had no effect on antioxidant activity until the 14th day, thereafter high pressure processing samples showed the highest antioxidant activity

    Food preservation under pressure (hyperbaric storage) as a possible improvement/alternative to refrigeration

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    Food preservation is highly dependent on refrigeration, which is limited by its high energy costs. Among alternatives being developed, this review focused on hyperbaric storage (food preservation under pressure). This new preservation methodology has as main objective microbial growth inhibition similarly to freezing and refrigeration, showing a great potential to lower energy costs since refrigerated/room temperatures (RT) can be used. This, even at variable (uncontrolled) RT (up to 37 C), has been shown to preserve foods and thus achieving significant energy savings. Covering the earliest up to the more recent studies, this review aimed to gather information about the state of art of hyperbaric storage at refrigerated and RTs, with the primary objective of showing it potential and possible future applications of this new preservation method based on microbial growth inhibition under pressure, using pressure as the main variable to slow down microbial growth

    Preservation under pressure (hyperbaric storage) at 25ºC, 30ºC and 37ºC of a highly perishable dairy food and comparison with refrigeration

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    Hyperbaric storage (HS) under mild pressure of requeijão, a traditional Portuguese whey cheese, as a case study of a highly perishable dairy food, was evaluated as a possible energy costless alternative to refrigeration. Whey cheese was stored for 4 and 8 hours, at different pressure levels (0.1, 100 and 150 MPa) and temperatures (25°C, 30°C and 37°C), and the results were compared with refrigeration (4°C). Microbial analyses showed that storage for 4 hours at 100 MPa was able to maintain microbial counts similar to refrigeration and initial load, ≈3 Log10 CFU/g, at all tested temperatures. By increasing the pressure to 150 MPa and the storage time to 8 hours, microbial loads were reduced to undetectable counts, with the exception for total aerobic mesophiles that were reduced to about ≈1 Log unit. HS in general maintained pH, water activity and lipid oxidation values, at levels similar to that in refrigeration

    Preservation of sliced cooked ham at 25, 30 and 37°C under moderated pressure (hyperbaric storage) and comparison with refrigerated storage

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    The feasibility of hyperbaric storage (HS) to substitute refrigeration as a lower energetic cost alternative to refrigeration, for sliced cooked ham preservation was assessed by using temperatures and pressures ranging 25–37◦C and 25–150 MPa for 4 and 8 h. At microbiological level, storage at 25 ◦C, 30 ◦C, and 37 ◦C, showed no effect on microbial growth at 25 MPa reaching levels similar to atmospheric pressure storage, around 5 log CFU/g for both total aerobic mesophiles (TAM) and lactic acid bacteria (LAB). Nevertheless, the storage at 50 MPa and 30 ◦C resulted in microbial growth inhibition, resulting in TAM and LAB counts similar to refrigeration, of about 3.8 log CFU/g for both the microorganisms. Additionally, the increase of the storage pressure to 100–150 MPa resulted in microbial inacti-vation, leading to microbial loads of almost 1 log CFU/g lower than refrigeration. In general, hyperbaric stored sliced cooked ham showed physicochemical parameters similar to the refrigerated samples. In conclusion, these results show that HS at uncontrolled (naturally variable room tem-perature conditions at 25–37 ◦C) is a promising alternative to refrigeration for cooked ham preservation. To this new preservation technology, no energetic costs are associated throughout storage, compared to refrigeration, needing only energy to generate the pressure and decompress, since no energy is required to maintain the pressure

    Preservation of a highly perishable food, watermelon juice, at and above room temperature under mild pressure (hyperbaric storage) as an alternative to refrigeration

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    The feasibility of food preservation under pressure (hyperbaric storage) at and above room temperatures, as an alternative to refrigeration was evaluated. Preservation of a highly perishable food, watermelon juice, was studied at pressures of 25e150 MPa and temperatures ranging 20e37 C, being compared to refrigeration and storage at atmospheric pressure at the same temperatures. Hyperbaric storage at 75 MPa (20e37 C) revealed an inhibitory effect on microbial growth, with at least an equal performance compared to refrigeration. An additional inactivation effect was verified for storage at 100 and 150 MPa, with reduction of the initial microbial counts to 1.00 Log CFU/mL for enterobacteriaceae and yeasts and moulds, and from 4.43 ± 0.04 to 3.31 ± 0.04 and 2.99 ± 0.07 Log CFU/ mL, respectively, for total aerobic mesophiles (25 C). In general, pH, titratable acidity and total soluble solids did not show a clear variation trend with pressure and no considerable differences among storage conditions were verified. Cloudiness decreased for samples stored under pressure and browning degree was in general lower in samples stored under pressure compared to refrigeration. This work demonstrates the potentiality of hyperbaric storage as a new preservation methodology, at variable (uncontrolled) room temperature without energetic costs during storage, as an alternative to refrigeration

    Fibromatosis of the Plantar Fascia: Diagnosis and Indications For Surgical Treatment

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    Plantar fibromatosis is a rare, benign lesion involving the plantar aponeurosis. Eleven patients (13 feet) underwent 24 operations, including local excision, wide excision, or complete plantar fasciectomy. Clinical results were evaluated retrospectively. There were no differences among the subgroups in postoperative complications. Two primary fasciectomies did not recur. Three of six revised fasciectomies, seven of nine wide excisions, and six of seven local excisions recurred. Our results indicate that recurrence of plantar fibromatosis after surgical resection can be reduced by aggressive initial surgical resection
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