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121.
EA Martinez JM Vazquez I Parrilla C Cuello MA Gil H Rodriguez-Martinez J Roca JL Vazquez 《Reproduction in domestic animals》2006,41(1):41-47
A new procedure for non-surgical deep intrauterine insemination (DUI) in unrestrained sows hormonally induced to ovulate, has been reported. In comparison with standard artificial insemination (AI), with this procedure, the sperm numbers inseminated can be reduced 20-fold without reducing the reproductive performance of these hormonally treated sows. The present study evaluated, using two experiments, the reproductive performance applying 20-fold different sperm numbers per AI dose using DUI or standard AI in spontaneously ovulating sows, under field conditions. In experiment 1, AI was applied to crossbred sows at 12, 24 and 36 h after onset of spontaneous oestrus using one of the following two regimes: (i) DUI (treatment) with 0.15 x 10(9) fresh boar spermatozoa in 5 ml of Beltsville thawing solution (BTS) extender (n = 95), and (ii) standard cervical AI (control) with 2.85 x 10(9) fresh spermatozoa in 95 ml of BTS extender (n = 95). The farrowing rates of the two groups of sows were statistically similar (NS). However, a decrease (p < 0.002) in litter size and the total number of pigs born alive was observed in sows inseminated with the DUI procedure. In experiment 2, 42 post-weaned oestrus sows were inseminated following the same design described for experiment 1 during spontaneous oestrus. On day 6 after onset of oestrus, the proximal segment of the uterine horns of the sows were flushed under surgery to retrieve eventual embryos and evaluate the success of fertilization per cornua (e.g. occurrence of effective uni- vs bilateral sperm transport rendering uni- or bilateral, complete or partial fertilization). Retrieved embryos were assessed for cleavage and number of accessory spermatozoa. Although identical overall pregnancy rates were achieved in both insemination groups, the percentage of sows with partial bilateral fertilization and unilateral fertilization was markedly higher (p < 0.05) in the DUI group (35%) compared with the control (standard AI) group (5%), with a consequent lower (p < 0.001) percentage of viable early embryos after DUI. The number of accessory spermatozoa in the zona pellucida of the embryos was highly variable, but higher (p < 0.001) in control animals than in DUI-AI. No accessory spermatozoa were found in oocytes retrieved from sows depicting unilateral fertilization. In conclusion, DUI in spontaneously ovulating sows with 0.15 x 10(9) spermatozoa renders similar farrowing rates but a lower litter size compared with use of standard AI with a 20-fold higher sperm dose. The lower litter size ought to be related to a decreased distribution of spermatozoa after DUI leading to a higher incidence of partial bilateral and unilateral fertilization. 相似文献
122.
Vertical induction of the inclusion body hepatitis/hydropericardium syndrome with fowl adenovirus and chicken anemia virus 总被引:2,自引:0,他引:2
The hypothesis that fowl adenovirus (FAV) and chicken anemia virus (CAV), transmitted vertically and simultaneously, induce the inclusion body hepatitis (IBH)/hydropericardium (HP) syndrome in progeny chickens was tested. Thus, 35-wk-old light brown layer breeders, showing absence of antibodies against FAV and variable titers against CAV, were intramuscularly singly infected with the FAV serotype 4 isolate 341 or dually infected with CAV (isolate 10343) and FAV. All hens (groups A [FAV alone], B [FAV + CAV], and C [noninfected]) were clinically healthy throughout the experimental period. Both infectious viruses FAV and CAV were isolated from progenies obtained as early as 5 days after infection of their breeders. Hematocrit, serum proteins, and aspartate-aminotransferase values showed a few statistical differences between the progeny groups. Most of these differences were detected in the progeny chickens of group B. However, almost all values met reference values for the species. The pathologic findings showed that progeny chickens obtained from both singly and dually infected breeders developed macroscopic and histopathologic changes of IBH/HP. The pathologic findings shown by progeny chickens of group A (FAV) were not expected because neither synergism nor prior immunodepression by CAV was concurrent. Chickens of group B (CAV + FAV) also developed IBH/HP. Although not many differences in the evaluated parameters between groups A and B were statistically significant, most pathologic findings of group B indicated a more severe manifestation of the disease. However, because FAV alone did reproduce the syndrome, the results shown by group B would not allow a definitive confirmation of the hypothesis that the association of FAV and CAV is necessary for the successful induction of the IBH/HP syndrome in chickens when transmitted vertically. 相似文献
123.
Effect of dietary conjugated linoleic acid and monounsaturated fatty acids on productive, carcass and meat quality traits of pigs 总被引:1,自引:0,他引:1
Diana Martin Elena Muriel Elena Gonzalez Javier Viguera Jorge Ruiz 《Livestock Science》2008,117(2-3):155-164
Three levels (0, 1 and 2%) of conjugated linoleic acid (CLA) were combined with two levels (low and high) of monounsaturated fatty acids (MUFA) for pig feeding. Productive, carcass and meat quality traits were studied. Large White ♂ × Landrace × Large White ♀ gilts (n = 288) weighting 70 kg were randomly allotted to 6 different feeding treatments and fed to a final average weight of 107 kg. Loins were taken from 48 animals (8 animals randomly selected from each treatment). No differences due to dietary CLA, MUFA or CLA × MUFA interaction were found on average daily gain, average daily consumption, feed conversion ratio, carcass yield, backfat thickness, loin weight, loin pH and loin colour. A significant increase in intramuscular fat content (p = 0.010) and in saturated fatty acids (SFA) (p < 0.001), and a decrease in MUFA (p = 0.001) and desaturase indices were found as consequence of dietary CLA, regardless the MUFA level. Therefore, dietary CLA, MUFA and their interaction did not influence productive and carcass traits of pigs. However, the use of CLA for swine feeding increased the intramuscular fat content and modified the fatty acid profile, regardless the MUFA level of the diets. 相似文献
124.
Harrison LJ Garate T Bryce DM Gonzalez LM Foster-Cuevas M Wamae LW Onyango-Abuje JA Parkhouse RM 《Tropical animal health and production》2005,37(2):103-120
A Taenia saginata oncosphere-derived adhesion protein (HP6) with surface and secreted localization was used to successfully vaccinate calves against oral challenge with T. saginata eggs. In contrast, vaccination using a combination of T. saginata oncosphere-derived peptides, selected on the basis of their antigenic index, and including three derived from the HP6 molecule (HP6-1, HP6-2 and HP6-3), was unsuccessful. This either indicated that the wrong peptides were selected or, in the case of the HP6 protein, that the protective epitope is conformational in nature. The protection experiments were monitored using a parasite antigen detection ELISA (HP10 Ag-ELISA), which allowed the early determination of the success of the vaccination protocol, subsequently confirmed at autopsy. PCR assays were used for the first time to confirm the presence of T. saginata DNA in lesions recovered at autopsy and thus verify the parasite origin of the lesions. 相似文献
125.
Maraisa Crestani José Antonio Gonzalez da Silva Elisane Weber Tessmann Itamara Mezzalira Antonio Costa de Oliveira Fernando Irajá Félix de Carvalho 《Journal of Crop Science and Biotechnology》2011,14(1):71-77
White oat genotypes were subjected to Al stress in hydroponic conditions in order to verify the viability of methods based
on minimum nutrient solution (MNS) in comparison to complete nutrient solution (CNS), commonly used in the characterization
and selection for Al tolerance in this species. The experimental design was completely randomized blocks with three replicates
composed of 10 seedlings each. Six white oat genotypes subjected to different Al levels in minimum (0, 3, 6, and 9 mg L−1) and complete (0, 10, 20, and 30 mg L−1) solutions were evaluated. In this evaluation, the MNS was efficient in identifying aluminum-tolerant, white oat genotypes
under hydroponics. The root growth resumption showed to be the most effective trait in the aluminum-tolerant plant selection.
At concentrations equal to or higher than 3 mg Al L−1 in minimum and 10 mg Al L−1 in complete solution, severe damage caused by the toxic element on root development was verified. The white oat cultivars
UFRGS 14, ALBASUL, and BARBARASUL showed aluminum tolerance in the tested conditions. 相似文献
126.
CASE HISTORY: A neonatal Thoroughbred foal was presented with rib fractures and left forelimb lameness secondary to dystocia. CLINICAL FINDINGS: The foal developed a head tilt, seizures and watery diarrhoea during hospitalisation and died at 7 days of age. Histological examination of the brain and spinal cord revealed a suppurative meningoencephalomyelitis with vasculitis, and numerous intralesional, gram-negative bacilli. Similar microscopic lesions were noted in the lungs, renal medullary interstitium, and umbilicus. Bacilli in the brain, spinal cord and umbilicus were identified immunohistochemically as Salmonella group B. Salmonella agona was isolated in pure culture from the brain, lung, liver, kidney, and intestine. CONCLUSION: This is the first report of meningoencephalomyelitis and septicaemia due to Salmonella infection in an equine neonate. 相似文献
127.
LA Gracia‐Calvo LJ Ezquerra M Martín‐Cuervo ME Durán H Tapio JM Gallardo FJ Peña C Ortega‐Ferrusola 《Reproduction in domestic animals》2014,49(6):1043-1048
Laparoscopic hernioplasty techniques have been developed in the recent years to avoid the recurrence of inguinal hernias and to spare the testicles for breeding purposes in stallions. However, there have been no previous comprehensive and systematic studies of the reproductive outcomes and prognoses for stallions after inguinal hernioplasty. Therefore, the objective of this study was to assess the possible effects of one of these techniques (standing laparoscopic peritoneal flap hernioplasty) on the sperm production and motility characteristics of six healthy stallions that received this procedure based on 1‐year follow‐ups. There were no significant differences in the measured sperm variables (assessments based on the DSO, MOT, PMOT, VSL, VCL and VAP) during 1‐year follow‐ups. 相似文献
128.
Two vaccines, based on formalin-killed whole cells of toxigenic Pasteurella multocida type D and Bordetella bronchiseptica combined with a partially toxoided cell extract of P multocida, were prepared with Freund's incomplete adjuvant (vaccine 1) or by alum precipitation (vaccine 2). Each was tested for safety and efficacy in reducing the severity of nasal turbinate atrophy and improving the growth rate of pigs in three Western Australian commercial piggeries with endemic atrophic rhinitis. In safety experiments with vaccine 1, no adverse clinical effects were observed in vaccinated sows or their progeny. Piglets receiving vaccine 2 showed no injection site abnormalities, pyrexia or turbinate atrophy. In field trials, vaccine 1 significantly reduced the prevalence of moderate to severe nasal turbinate atrophy (Done score 3 to 5) when used in two piggeries (A and B). Progeny from vaccinated sows in piggery B also grew significantly faster than controls. When vaccine 2 was used in piggery A at a later date and in another piggery (C), growth rate was not improved in either piggery and the prevalence of moderate to severe turbinate atrophy was reduced only in piggery C. 相似文献
129.
Soulen Jr RJ JM Byers MS Osofsky B Nadgorny T Ambrose SF Cheng Broussard C T Tanaka PR J Nowak JS Moodera A Barry JMD Coey 《Science (New York, N.Y.)》1998,282(5386):85-88
A superconducting point contact is used to determine the spin polarization at the Fermi energy of several metals. Because the process of supercurrent conversion at a superconductor-metal interface (Andreev reflection) is limited by the minority spin population near the Fermi surface, the differential conductance of the point contact can reveal the spin polarization of the metal. This technique has been applied to a variety of metals where the spin polarization ranges from 35 to 90 percent: Ni0.8Fe0.2, Ni, Co, Fe, NiMnSb, La0.7Sr0.3MnO3, and CrO2. 相似文献
130.
Implications of iron solubilization on soil phosphorus release in seasonally flooded forests of the lower Orinoco River, Venezuela 总被引:1,自引:0,他引:1
The microbial reduction of Fe oxides is thought to contribute with the release of P in sedimentary environments. However, secondary reactions of the bioproduced Fe(II) with P in solution, can lead to a decrease in the soluble P concentration. In this study, we examined how the reduction of Fe(III) affects the soluble P concentration, when the soils of a seasonally flooded forest gradient are subjected to anaerobic conditions. Soil samples were collected during the dry season from two zones subjected to different flooding intensity: MAX and MIN zones that were inundated 8 and 2 months per year, respectively. When anaerobic conditions were applied to soils from both zones, a clear stimulatory effect on the Fe(III) reduction was observed. However, bioproduced Fe(II) underwent secondary chemical reactions, masking the extend of Fe(III) reduction of these soils. Iron was reduced mainly during the first 15 days of the anaerobic incubation and it was stimulated by a pulse of labile carbon. Iron dissolution did not lead to an increase of the soluble P content. However, in both zones P was high and positively correlated with Fe(II), implying that soil P mobilization was linked to Fe dissolution. In the MIN zone, soluble P concentration decreased, probably as a consequence of the secondary reactions of solubilized P with other non-redox sensitive soils elements. Fe solubilization also had an effect on the activity of acid phosphatase and consequently in the solubilization of P from the organic pool. In conclusion, the P cycle in these soils is strongly coupled to C and Fe cycles. 相似文献