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ANC Castro MC Díaz GJ Mendoza‐Torres CA Llerena‐Zavala MD Ghezzi CG Barbeito 《Reproduction in domestic animals》2018,53(3):655-666
The breeding of South American camelids is the main economic activity of the high Andean region of South America and it, is potentially, the most profitable resource in of the Puna environmental conditions of the Puna. The duration of the gestation in alpaca is 339.7 ± 12 days. The objective of the present work was to macroscopically and microscopically describe the ontogenic development of the splanchnic cavities of the alpaca and to determine the gestational time in which the post‐cranial ossification centers are observed in the embryos/fetuses of this species, from day 21 to 107 of gestation. The documentation of normal ontogenic development, which is vacant for this period, is of the utmost importance to understand the consequences of the alterations at the different gestational times, as well as for the estimation of the gestational age in the case of abortions. Forty‐seven alpaca specimens of both sexes, at different times of their gestational development, collected during slaughter at local slaughterhouses of the Department of Huancavelica, Peru, were evaluated. Specimens were assigned to seven groups according to their morphological characteristics. The embryogenesis in the alpaca was characterized by a series of changes comparable to those occurring in other mammals with similar gestational periods. Despite these similarities, species differences were found in some organs as stomach, which are observed too in adult individuals. 相似文献
85.
Jingjuan Zhang MD Shahidul Islam Yun Zhao Masood Anwar Zaid Alhabbar Maoyun She Rongchang Yang Angela Juhasz Guixiang Tang Jiansheng Chen Hang Liu Yanjie Jiang Shengnan Zhai Xin Hu Junkang Rong Yingquan Zhang Yebo Qin Qier Liu Zitong Yu Yujuan Zhang Sadegh Balotf Mirza Dowla Sonia Afrin Nandita Roy Md Resad Mallik Md Atik Us Saieed Shanjida Rahman Nigarin Sultana Sarah Al-Sheikh Ahmed Chris Florides Kefei Chen Darshan Sharma Nathan Height Ben Biddulph Meiqin Lu Jorge EMayer Wujun Ma 《作物学报(英文版)》2022,(1):147-165
Reproductive stage frost poses a major constraint for wheat production in countries such as Australia.However,little progress has been made in identifying key genes to overcome the constraint.In the present study,a severe frost event hit two large-scale field trials consisting of six doubled haploid(DH)wheat populations at reproductive stage(young microspore stage)in Western Australia,leading to the identification of 30 robust frost QTL on 17 chromosomes.The major 18 QTL with the phenotype variation over 9.5%were located on 13 chromosomes including 2 A,2 B,2 D,3 A,4 A,4 B,4 D,5 A,5 D,6 D,7 A,7 B and7 D.Most frost QTL were closely linked to the QTL of anthesis,maturity,Zadok stages as well as linked to anthesis related genes.Out of those,six QTL were repetitively detected on the homologous regions on 2 B,4 B,4 D,5 A,5 D,7 A in more than two populations.Results showed that the frost damage is associated with alleles of Vrn-A1 a,Vrn-D1 a,Rht-B1 b,Rht-D1 b,and the high copy number of Ppd-B1.However,anthesis QTL and anthesis related genes of Vrn-B1 a and Ta FT3-1 B on chromosomes 5 B and 1 B did not lead to frost damage,indicating that these early-flowering phenotype related genes are compatible with frost tolerance and thus can be utilised in breeding.Our results also indicate that wild-type alleles Rht-B1 a and Rht-D1 a can be used when breeding for frost-tolerant varieties without delaying flowering time. 相似文献
86.
C. Guillermo Couto José J. Cerón MD Parra Silvi Martínez‐Subiela M. Cristina Lazbik 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2009,38(2):219-223
Background: Retired racing Greyhounds are popular as pets. Greyhounds have several differences in physiological values compared with other breeds, including lower serum α‐ and β‐globulin concentrations. We hypothesized that lower acute phase protein (APP) concentrations could contribute to lower α‐ and β‐globulin concentrations in this breed. Objectives: The purpose of this study was to compare serum concentrations of several APPs in Greyhounds with those of other dog breeds. Methods: We measured the serum concentrations of C‐reactive protein (CRP), haptoglobin (Hp), acid‐soluble glycoprotein (ASG), ceruloplasmin (CP), and serum amyloid A (SAA) in 15 clinically healthy retired racing Greyhounds and 11 age‐ and gender‐matched healthy nonGreyhound controls using previously validated methods. Results were compared by Student's t‐tests. Results: The concentration of Hp by both colorimetric and immunoturbidimetric methods was significantly lower in Greyhounds than in nonGreyhound dogs (P=.0009 and .019, respectively). The concentration of ASG was also significantly (P=.007) lower in Greyhounds, but CRP and CP concentrations were not significantly different between groups. SAA concentration was below the detection limit of the method in all dogs. Conclusions: The low serum concentrations of Hp and ASG should be taken into consideration when interpreting APP results in Greyhounds. Because both Hp and some ASG migrate in the α‐globulin fraction, these results may explain the low α‐globulin concentrations in Greyhounds. 相似文献
87.
Leandro Maia MV MS Maria Vernica de Souza MV MS DS Pharmacist-Biochemical Jos Ivo Ribeiro Júnior BS MS DS Acio Carlos de Oliveira Geraldo Eleno Silveira Alves MV MS DS Larcio dos Anjos Benjamin MV MS DS Yamê Fabres Robaina Sancler Silva Bruna Mota Zandim MV Jos do Carmo Lopes Moreira MD MS 《Journal of Equine Veterinary Science》2009,29(8):618-626
This study was carried out to evaluate the effect of platelet-rich plasma (PRP) on the treatment of tendinopathy induced in the superficial digital flexor tendon (TFDS) of horses, by using histologic evaluation. Six healthy crossbred geldings aged 8 to 15 years (12 ± 3) were used. The TFDS tendinopathy was provoked in both forelimbs, by intratendinous administration of 2.5 mg collagenase (2.5 mg/mL), and this procedure was considered as the beginning of the experimental phase. At 12 days after induction of the tendinopathy, the animals were subjected to the following treatments: (1) in the lesion caused in the right superficial digital flexor tendon (PRP-treated group), 2.5 mL PRP activated with calcium chloride at 0.0125 mol/L at concentrations from 320,000 to 500,000 platelets/μL, were injected; (2) in the tendinopathy of the left SDFT (control group), 2.5 mL 0.9% saline solution was administrated. Thirty-six days after the treatments, a biopsy of the injured area was performed for histologic evaluation. In both groups, the histologic analysis showed an increase in the fibroblastic density, as well as the presence of neovascularization, lymphocytes, and plasmocytes infiltrate and tissue organization at variable intensity. In the PRP-treated group, the SDFT was more organized, with the collagen fibers and fibroblasts being better arranged on the tendon matrix. The numbers of the fibroblasts and blood vessels did not differ between the groups. Histologic evaluation 36 days after tendinopathy showed that injuries under a single PRP treatment present a more uniform and organized tissue repair when compared with the control group. 相似文献
88.
Daniel Schenkman DVM PhD Anibal Armien DVM PhD Roy Pool Jr. DVM PhD James M. Williams PhD Ronald D. Schultz PhD Jorge O. Galante MD 《Journal of Equine Veterinary Science》2009,29(10):748-752
Recently Degenerative Suspensory Ligament Desmitis (DSLD) has been proposed to be a disease characterized by systemic deposition of proteoglycan (PG) in connective tissues. To investigate this hypothesis, 6 clinically affected Peruvian Paso horses were compared to 2 unaffected quarterhorses and one unaffected standardbred. Histological sections of limb ligaments and tendons, nuchal ligaments, aortas, hearts, eyes, visceral organs and brains from both groups were stained with H&E as well as special stains for PG. Safranin-O stained sections were found to be optimal for elucidating the presence of PG. Although lesions characteristic of DSLD were present in suspensory ligaments of each clinically affected horse, including foci of chondroid metaplasia with abundant PG, a similar but less pronounced pattern of PG deposition was present in control horses. In contrast to findings of the previous study, PG deposition was not unique to DSLD horses, and PG deposition in aortas and nuchal ligaments of some control horses exceeded levels of PG present in similar tissue of DSLD horses. Furthermore, the “vascular lesion” described in the media of arteries as cellular separation and intercellular amorphous matrix deposition was within the spectrum of changes recognized in both affected and unaffected horses. We found no evidence that DSLD is a systemic PG deposition disease. 相似文献
89.
LA Quintela AI Peña MD Vega J Gullón C Prieto M Barrio JJ Becerra PG Herradón 《Reproduction in domestic animals》2009,44(5):829-833
This study was aimed to evaluate the reproductive performance of rabbit does artificially inseminated (AI) with a GnRH analogue [des‐Gly10, d ‐Ala6]‐LHRH. ethylamide to induce ovulation by intravaginal administration, delivered in the seminal dose. In a preliminary experiment, 39 does were divided into three groups (n = 13) that, at the time of AI, received the following ovulation induction treatments: (i) control group: 20 μg of gonadorelin administered intramuscularly; (ii) 25 μg of the GnRH analogue added to the seminal dose; (iii) 30 μg of the GnRH analogue added to the seminal dose. Fertility did not differ between the three groups (control: 80.6%, group 2: 82.8%, group 3: 73.3%). In a second experiment, a large‐scale field trial was conducted to test the use of 25 μg of the GnRH analogue [des‐Gly10, d ‐Ala6]‐LHRH ethylamide delivered in the seminal dose (n = 270) against 20 μg of gonadorelin administered intramuscularly. Fertility was higher (p < 0.05) when ovulation was induced by intravaginal administration of the GnRH agonist (91.1% vs 85.6%). Prolificacy or mortality at birth was never affected by the ovulation induction treatments. In a third experiment, two groups of does [control group (n = 39): ovulation was induced using 20 μg of gonadorelin administered intramuscularly; treatment group (n = 40): ovulation was induced using 25 μg of [(des‐Gly10, d ‐Ala6)‐LHRH ethylamide added to the seminal dose] were inseminated at 42‐day intervals for five successive AI cycles, to test the response to the GnRH agonist after repeated intravaginal administration to the same animals. Fertility and prolificacy were not influenced by the ovulation induction treatment neither there was an interaction between treatment and parity. The last experiment was aimed to determine whether it could be possible to add the GnRH agonist to the semen in the AI Center, just after semen collection and dilution, or it would have to be added in the farm, immediately before AI. Kindling rates did not significantly differ when ovulation was induced by intramuscular injection of gonadorelin (84.5%) or when the GnRH agonist was added to the seminal dose just at the moment (93.8 %) or 24 h before AI (90.4 %), but it was significantly lower when the hormone was added to the semen 32 h before AI (76.3 %). Prolificacy, however, was not influenced by the ovulation induction treatment. 相似文献