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31.
Saulo PS Guerra Guilherme Oguri Marcelo S Denadai Maura ST Esperancini 《Southern Forests》2018,80(2):131-135
The increasing demand for renewable energy feedstock has raised interest in growing eucalypts for fuel wood production, which is achieved by establishing very dense plantations cut every 18–24 months. The high moisture content of fresh Eucalyptus may handicap cut-and-chip operations, and offers a unique opportunity for supply chains based on baling. Therefore, the Canadian-made BioBaler was tested in Brazil on a eucalypt energy plantation, as well as on the resprouts generated by a conventional pulpwood plantation after severe frost damage. The BioBaler coped well with both crops, achieving high productivity levels: 7.1 and 3.3 t h?1 in the energy plantation and the failed crop treatments, respectively. Harvesting cost was estimated at €13 t?1 and €26 t?1 for the energy plantation and the failed crop, respectively. Productivity and harvesting cost were comparable with those reported in previous studies conducted in other countries on similar crops. Productivity was directly proportional to field stocking. Future studies should test the machine on a wider range of work conditions and include bale extraction, storage, processing and transportation, in order to estimate an overall supply chain cost and allow direct comparison with alternative options. 相似文献
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The results of massively parallel three-dimensional molecular dynamics simulations of the perpendicular intersection of extended dislocations in copper are reported. The intersection process, which involves three of the four possible 111 glide planes in the face-centered cubic lattice, begins with junction formation, followed by unzipping, partial dislocation bowing, cutting, and, finally, unit jog formation. The investigation provides insights into this complex atomistic process, which is currently not accessible to experimental investigation. 相似文献
33.
LM Pettett GJ Wilson V Nicolson WSJ Boardman N Speight J Fabijan DJ Trott PS Bird 《Australian veterinary journal》2019,97(11):473-481
Malocclusions are a misalignment or incorrect positioning of the teeth when the upper and lower jaws close. These are poorly described in the koala and can result in irregular mastication which can have lifelong effects on body condition and oral health. A total of 370 koalas from two populations in Queensland (295) and one in South Australia (75) were examined for malocclusions. The prevalence of malocclusions in South Australian free‐ranging koalas, captive Queensland koalas and Queensland free‐ranging koalas was 39% (44), 30% (29) and 22% (29) respectively. Four types of malocclusion were identified based on severity of misalignment of the incisor/canine region, types 1, 2, 3 and 4. Maxillary overbite measurements of the molariform teeth were determined and these anisognathic values were then used to describe malocclusions within familial relationships in captive colonies. Captive koalas with a malocclusion had narrower mandibular width that ranged between 0.5 and 1% less than the normal measurements. The specific malocclusions reported in this study affected individuals by leading to tooth rotation, mobility and erosion with inefficient mastication of food and vegetation compaction. These changes increased the oral cavity pathology, by placing animals at risk of periodontal disease. There was evidence of familial links to malocclusion types in captive animals. Therefore captive breeding recommendations should consider known koala malocclusion traits to minimise their effect on future generations. 相似文献
34.
Ovarian Follicular Dynamics in Buffalo Cows (Bubalus bubalis) 总被引：1，自引：0，他引：1
A Ali AK Abdel-Razek S Abdel-Ghaffar PS Glatzel 《Reproduction in domestic animals》2003,38(3):214-218
Follicular growth in Egyptian buffalo cows was monitored using genital tracts from 200 buffalo cows collected immediately after slaughter. According to the morphological appearance of the corpus luteum (CL), the corresponding oestrous cycle was divided into four stages: A (days 1–4), B (days 5–10), C (days 11–17) and D (days 18–21). Within these stages the follicular population on the ovaries was evaluated and the dominant follicle (DF) determined in all recovered ovaries. The functional status of the DF and the largest sub‐dominant follicles was examined by histological examination in 31 cases, and Radio Immunoassay (RIA) analyses for estradiol‐17β (E2) and progesterone (P4) was performed in the follicular fluid in 23 of the DF. The results showed that DFs changed their endocrine character within the stages of the oestrous cycle. The DFs between days 5 and 10 were functionally active (E2‐dominant; non‐atretic) in most of the cases. Between days 11 and day 17 half of the DFs became functionally inactive (P4‐dominant; atretic). At days 18–21 all of the DF became functionally active and non‐atretic. In the specimens that carried two large follicles one of them was regularly atretic and P4‐dominant whereas the other was non‐atretic and E2‐dominant. Between days 18 and 21 all ovaries examined showed at least one large follicle. These findings suggest that in most of the cases follicular dynamics occurs in two wave‐like patterns in the Egyptian buffalo cows. 相似文献
35.
Ovarian responses of dairy buffalo cows to timed artificial insemination protocol,using new or used progesterone devices,during the breeding season (autumn–winter) 
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下载免费PDF全文 Bruno Moura Monteiro Diego Cavalcante de Souza Guilherme Souza Floriano Machado Vasconcellos Thalita Bueno Corrêa Domenico Vecchio Manoel Francisco de Sá Filho Nelcio Antonio Tonizza de Carvalho Pietro Sampaio Baruselli 《Animal Science Journal》2016,87(1):13-20
This study evaluated the effect of new or used P4 devices on the ovarian responses of dairy buffalo that were administered an estradiol (E2) plus progesterone (P4)‐based timed artificial insemination (TAI) protocol during the breeding season. On the first day of the TAI protocol, 142 cows were randomly assigned to receive one of the following: a new device (New; 1.0 g of P4; n = 48); a device that had previously been used for 9 days (Used1x, n = 47); or a device that had previously been used for 18 days (Used2x, n = 47). Ultrasound was used to evaluate the following: the presence of a corpus luteum (CL); the diameter of the dominant follicle (ØDF) during protocol; ovulatory response; and pregnancies per AI (P/AI). Despite similar responses among the treatments, there was a significant positive association of the ØDF during TAI protocol with ovulatory responses and number of pregnancies. In conclusion, satisfactory ovarian responses and a satisfactory pregnancy rate were achieved when grazing dairy buffalo were subjected to the TAI protocol in breeding season, independent of whether a new or used P4 device was used. Furthermore, the presence of the larger follicle was associated with a higher ovulation rate and higher P/AI following TAI. 相似文献
36.
Estimation of endogenous levels of osteopontin,total antioxidant capacity and malondialdehyde in seminal plasma: Application for fertility assessment in buffalo (Bubalus bubalis) bulls 下载免费PDF全文
下载免费PDF全文 This study was attempted to identify subfertile bulls by quantifying the endogenous levels of osteopontin (OPN), total antioxidant capacity (TAC) and malondialdehyde (MDA) in seminal plasma of buffalo bulls. On the basis of conception rate, buffalo bulls were classified into two groups: high‐fertile (conception rate >50%) and subfertile bulls (conception rate <40%). A total of 100 ejaculates (10 ejaculates from each bull) were collected through artificial vagina method. The concentration of OPN, TAC and catalase (CAT) of high‐fertile bulls was found to be higher (p < .05) than that of subfertile bulls. Further, MDA level in seminal plasma was found to be lower (p < .05) in high‐fertile bulls compared with subfertile bulls. The fertility status had no effect on the superoxide dismutase (SOD) concentration in seminal plasma of both the groups. The levels of OPN (r = .678, p = 0.013) and TAC (r = .648, p = .042) were found to be positively correlated with bull fertility and the level of MDA (r = ?.718, p = .019) was found to be negatively correlated with bull fertility. However, the fertility of bulls was not found to be significantly correlated with SOD, CAT and sperm motility. In conclusion, seminal OPN, TAC and MDA tended to be more realistic in identification of subfertile bulls from breeding herds. 相似文献
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38.
EOS Batista GG Macedo RV Sala MDDV Ortolan MF Sá Filho TA Del Valle EF Jesus RNVR Lopes FP Rennó PS Baruselli 《Reproduction in domestic animals》2014,49(3):448-452
In Bos taurus cattle, antimullerian hormone (AMH) has been demonstrated to have a high degree of correlation with ovarian antral follicle count and the number of healthy follicles and oocytes. To document the correlation between the plasma concentration of AMH and follicular number in Bos indicus and Bos taurus heifers, Nelore (Bos indicus, n = 16) and Holstein heifers (Bos taurus, n = 16) had their ovarian follicular waves synchronized. After synchronization, ovarian antral follicular population (AFP) was evaluated three times at 60‐day (d) intervals (T‐120 d, 120 days before plasma AMH determination; T‐60 d, 60 days before; and T0, at the time of plasma AMH determination). The plasma AMH concentration was positively correlated with the number of ovarian follicles on the day of the follicular wave emergence in Bos indicus (Nelore) and Bos taurus (Holstein) heifers at each evaluation time (p < 0.05). The AFP was higher in Bos indicus (Nelore) than in Bos taurus (Holstein) heifers (p < 0.05). Similarly, the AMH concentration was higher in Bos indicus (Nelore) than in Bos taurus (Holstein) heifers (p < 0.0001). When heifers were classified as to present high or low AFP according to the mean of the AFP within each genetic group, high‐AFP heifers presented a greater (p < 0.0001) AMH concentration than low‐AFP heifers, regardless of the genetic group. In conclusion, the AFP is positively correlated with plasma AMH concentration in both Bos indicus (Nelore) and Bos taurus (Holstein) heifers. Furthermore, Bos indicus (Nelore) heifers presented both greater plasma AMH concentrations and AFP than Bos taurus (Holstein) heifers. 相似文献
39.
Yves PS Moens DVM PD PhD Diplomate ECVAA Peter Gootjes† Ing Jean-Claude Ionita‡ DVM Erkki Heinonen§ Lic Tech PhD & Urs Schatzmann‡ DVM PhD Diplomate ECVAA 《Veterinary anaesthesia and analgesia》2009,36(3):209-219
Objective To remodel and validate commercially available monitors and their Pitot tube-based flow sensors for use in large animals, using in vitro techniques.
Study design Prospective, in vitro experiment.
Methods Both the original and the remodelled sensor were studied with a reference flow generator. Measurements were taken of the static flow-pressure relationship and linearity of the flow signal. Sensor airway resistance was calculated. Following recalibration of the host monitor, volumes ranging from 1 to 7 L were generated by a calibration syringe, and bias and precision of spirometric volume was determined. Where manual recalibration was not available, a conversion factor for volume measurement was determined. The influence of gas composition mixture and peak flow on the conversion factor was studied.
Results Both the original and the remodelled sensor showed similar static flow–pressure relationships and linearity of the flow signal. Mean bias (%) of displayed values compared with the reference volume of 3, 5 and 7 L varied between −0.4% and +2.4%, and this was significantly smaller than that for 1 L (4.8% to +5.0%). Conversion factors for 3, 5 and 7 L were very similar (mean 6.00 ± 0.2, range 5.91–6.06) and were not significantly influenced by the gas mixture used. Increasing peak flow caused a small decrease in the conversion factor. Volume measurement error and conversion factors for inspiration and expiration were close to identity.
Conclusion The combination of the host monitor with the remodelled flow sensor allowed accurate in vitro measurement of flows and volumes in a range expected during large animal anaesthesia.
Clinical relevance This combination has potential as a reliable spirometric monitor for use during large animal anaesthesia. 相似文献
Study design Prospective, in vitro experiment.
Methods Both the original and the remodelled sensor were studied with a reference flow generator. Measurements were taken of the static flow-pressure relationship and linearity of the flow signal. Sensor airway resistance was calculated. Following recalibration of the host monitor, volumes ranging from 1 to 7 L were generated by a calibration syringe, and bias and precision of spirometric volume was determined. Where manual recalibration was not available, a conversion factor for volume measurement was determined. The influence of gas composition mixture and peak flow on the conversion factor was studied.
Results Both the original and the remodelled sensor showed similar static flow–pressure relationships and linearity of the flow signal. Mean bias (%) of displayed values compared with the reference volume of 3, 5 and 7 L varied between −0.4% and +2.4%, and this was significantly smaller than that for 1 L (4.8% to +5.0%). Conversion factors for 3, 5 and 7 L were very similar (mean 6.00 ± 0.2, range 5.91–6.06) and were not significantly influenced by the gas mixture used. Increasing peak flow caused a small decrease in the conversion factor. Volume measurement error and conversion factors for inspiration and expiration were close to identity.
Conclusion The combination of the host monitor with the remodelled flow sensor allowed accurate in vitro measurement of flows and volumes in a range expected during large animal anaesthesia.
Clinical relevance This combination has potential as a reliable spirometric monitor for use during large animal anaesthesia. 相似文献