Normal Lamb Research Articles

Impact of Four Ovine TMEM154 Haplotypes on Ewes during Multiyear Lentivirus Exposure.

Polypeptide variation encoded by the ovine transmembrane protein 154 gene (TMEM154) is associated with susceptibility to ovine lentivirus, the causative agent of Ovine Progressive Pneumonia (OPP) and Visna/Maedi. Our aim was to compare the four most prevalent TMEM154 haplotypes on the incidence of infection and ewe productivity during natural multiyear virus exposure. Prospective cohort studies were designed to test gene action and estimate effects of TMEM154 haplotypes encoding distinctive variant residues: K35 (“1”), I70 (“2”), ancestral (“3”), and A4del/M44 (“4”). Exposure consisted of co-mingling infected ewes at a rate greater than 30% with serological status evaluated every four months. For ewes with one or two copies of the highly susceptible haplotypes “2” and ”3”, the infection prevalence steadily increased to nearly 100% at 55 months. Haplotypes “2” and “3” were equally susceptible and dominant to haplotype “1”. A difference was not detected (p < 0.53) in the magnitude of effect with haplotype combinations of “1” and ”4”. The ewe infection prevalence with “1,1”; “1,4”; and “4,4” was 10% to 40% at 55 months. The latter suggested that two copies of the K35 amino acid substitution (“1”) were as effective as a homozygous TMEM154 “knockout” with the frame-shift deletion mutation (“4”) in reducing infection susceptibility. When considering ewe reproductive performance, a difference was not detected when comparing haplotypes “2”, and “3” to each other, or “1” and “4” to each other. Our study indicated that ewes with two copies of the severely truncated versions of TMEM154 (“4,4”) had normal lamb productivity. Without complete understanding of the natural function of TMEM154 our recommendations to producers interested in using TMEM154 selection to reduce their flock’s genetic predisposition to OPP are encouraged to increase the frequency of TMEM154 haplotype K35 (“1”) since it encodes a full-length protein with minimal difference to the ancestral polypeptide.

Abstract 11646: Impact of Fetal Hypoxia on Myocardial Molecular Profile in the Lamb Extra-Uterine Environment for Neonatal Development

Background: Using the EXTrauterine Environment for Neonatal Development (EXTEND) system to chronically reduce myocardial oxygen delivery (DO 2 ) to levels mimicking human congenital heart disease caused increased myocardial capillarity and cardiomyocyte hypotrophy. However, molecular mechanisms for this have not been evaluated. Methods: Preterm fetal lambs were isolated by cesarean section and supported by EXTEND for 7 days in normoxia (n=5) or hypoxia (n=4) and compared to in utero gestational age matched controls (n=3). Right and left ventricle (RV, LV) molecular profiles were assessed by RNAseq, qPCR, and western blot. Differentially expressed genes (DEGs) were identified with limma/edgeR. BioPlanet enrichment analysis was performed with Enrichr. Results: DO 2 was lower in hypoxic lambs (15.5 vs 23.8 ml/kg/min, p&lt;0.0001). RNAseq revealed no significant DEGs between normoxia and control, while hypoxia significantly altered myocardial gene expression. The directionality was similar for LV and RV (r=0.82, p&lt;0.0001), but more statistically significant in LV (97 vs 7 DEGs, adj p&lt;0.05). Enrichment analysis revealed Hif1-target upregulation. qPCR confirmed upregulation of Hif1 targets and apoptosis activators Bnip3 (RV log 2 fold change (FC) 0.8) and Bnip3l (LV log 2 FC 1.6) and downregulation of the antiapoptotic Angpt1 (RV log 2 FC -1.5; all p&lt;0.05). However, by protein, Bnip3 and Bnip3l were reduced (RV FC 0.6, p&lt;0.0001) and (LV FC 0.8, p=0.0001), Bax was equally reduced (RV and LV FC 0.65, p&lt;0.05), and the proangiogenic/antiapoptotic hormone Angptl4 was increased (FC 1.9 RV and 2.3 LV, p&lt;0.05). In contrast, the proangiogenic/antiapoptotic cadherin receptor Cdh13 was reduced (RV and LV FC 0.5, p&lt;0.05). Finally, Fblim1 , a driver of cardiomyocyte hypertrophy, was decreased in LV and RV by RNAseq (logFC -0.75 and -0.63, adj p&lt;0.05) but increased by protein (LV FC 1.9, p=0.006). Conclusions: The normoxic EXTEND system faithfully recapitulates the myocardial molecular profile of normal lamb gestation. The molecular impact of fetal myocardial hypoxia is heterogeneous and suggests negative feedback loops with alterations in angiogenesis and cell survival/size. Future studies will dissect if these changes are sufficient to alter myocardial structure.

A new insight into meat toughness of callipyge lamb loins - The relevance of anti-apoptotic systems to decreased proteolysis

The objective of this study was to determine associations of small heat shock proteins (sHSPs) in tenderness development of loins from callipyge and normal genotype lambs. Loins (M. longissimus lumborum) from sixteen lambs across four genotypes were collected throughout 9 days of postmortem aging. The loins from callipyge lambs had more intact desmin and troponin T throughout aging periods, as well as less μ-calpain autolysis and more calpastatin compared to loins from other genotypes (P < 0.05). Delayed onset of apoptosis was found in the callipyge loins indicated by less cytochrome c and more inactive procaspase-3 compared to normal lamb loins (P < 0.05). Less degraded HSP27 was also consistently found in the callipyge loins compared with loins from normal lambs (P < 0.001). The results found up-regulation of anti-apoptotic activities coincided with toughness in callipyge loins, which suggest apoptosis is likely involved in postmortem proteolysis and subsequent meat tenderization.

Reproductive losses caused by the ingestion of Poincianella pyramidalis in sheep

Malformations have been observed in sheep and goats in the Brazilian semiarid region in areas where Poincianella pyramidalis is dominant. The objective of this trial was to determine whether Poincianella pyramidalis causes reproductive changes in pregnant sheep. Sixteen non-pregnant sheep were mated with two rams. After confirmation of the pregnancy by ultrasonography on the 18th day after mating, pregnant sheep were randomly divided into four groups (#1, 2, 3, and 4), with four animals each. Sheep received roughage in an amount equivalent to 2% of their body weight, mixed with 0%, 10%, 20% and 40% of dried leaves of P. pyramidalis for groups 1, 2, 3 and 4, respectively. In Groups 1 and 2, all animals lambed normally. In Group 3 (20% P. pyramidalis in the roughage), one lamb was born with arthrogryposis and three sheep gave birth to premature weak lambs within 128, 132, and 133 days of gestation. In Group 4 (40% P. pyramidalis in the roughage), one sheep lambed a normal lamb; another ewe had embryonic mortality after seven days of plant consumption, and two aborted on days 103 and 144 of pregnancy. One of the aborted fetuses was normal and the other showed arthrogryposis and prognathism. These results suggest that P. pyramidalis causes embryonic deaths, abortions, and malformations in sheep. Grazing pregnant sheep in areas where this plant is dominant should be avoided, and roughage for confined pregnant females should not contain more than 10% P. pyramidalis.

Method for calculation of piezo-ceramic transducer transmission characteristics in the mode of ultrasonic waves excitation. Part2. Calculation of coefficient of mechanoacoustical converters in mode of normal Lamb wave excitation

Method for calculation of piezo-ceramic transducer transmission characteristics in the mode of ultrasonic waves excitation. Part2. Calculation of coefficient of mechanoacoustical converters in mode of normal Lamb wave excitation

Antenatal antioxidant treatment with melatonin to decrease newborn neurodevelopmental deficits and brain injury caused by fetal growth restriction

Fetal intrauterine growth restriction (IUGR) is a serious pregnancy complication associated with increased rates of perinatal morbidity and mortality, and ultimately with long-term neurodevelopmental impairments. No intervention currently exists that can improve the structure and function of the IUGR brain before birth. Here, we investigated whether maternal antenatal melatonin administration reduced brain injury in ovine IUGR. IUGR was induced in pregnant sheep at 0.7 gestation and a subset of ewes received melatonin via intravenous infusion until term. IUGR, IUGR + melatonin (IUGR + MLT) and control lambs were born naturally, neonatal behavioral assessment was used to examine neurological function and at 24 hr after birth the brain was collected for the examination of neuropathology. Compared to control lambs, IUGR lambs took significantly longer to achieve normal neonatal lamb behaviors, such as standing and suckling. IUGR brains showed widespread cellular and axonal lipid peroxidation, and white matter hypomyelination and axonal damage. Maternal melatonin administration ameliorated oxidative stress, normalized myelination and rescued axonopathy within IUGR lamb brains, and IUGR + MLT lambs demonstrated significant functional improvements including a reduced time taken to attach to and suckle at the udder after birth. Based on these observations, we began a pilot clinical trial of oral melatonin administration to women with an IUGR fetus. Maternal melatonin was not associated with adverse maternal or fetal effects and it significantly reduced oxidative stress, as evidenced by reduced malondialdehyde levels, in the IUGR + MLT placenta compared to IUGR alone. Melatonin should be considered for antenatal neuroprotective therapy in human IUGR.

An experimental study of the characteristics of the acoustic field of zero normal plate modes

The sources of systematic errors in measuring the amplitude and propagation velocity of normal waves are analyzed. Criteria are proposed for estimating the distances beyond which a wave can be considered a normal wave. The measurement method and corresponding experimental setup are described. Experimental estimates are obtained for the distances necessary for the formation of symmetric zero modes of horizontally polarized normal waves and Lamb waves in thin strips at frequencies of 1.8 and 2.5 MHz.

Malformações, abortos e mortalidade embrionária em ovinos causada pela ingestão de Mimosa tenuiflora (Leguminosae)

Para determinar a teratogenicidade de Mimosa tenuiflora, 15 ovelhas, distribuídas em dois grupos, foram introduzidos em área invadida pela planta. O Grupo 1, com seis ovelhas prenhes, foi introduzido na área experimental 20 dias após o acasalamento. O Grupo 2, formado por nove ovelhas não prenhes e um carneiro, foi introduzido na área experimental no início do experimento. O experimento começou no mês de outubro de 2009, período de estiagem, quando M. tenuiflora estava sementando. Nesse período as plantas foram rebaixadas a 40 cm de altura e os galhos com folhas e sementes foram disponibilizados para os ovinos na mesma área onde M. tenuiflora foi rebaixada. M. tenuiflora começou a rebrotar ainda na estação seca antes do período de chuvas. No período de rebrota, as ovelhas ficavam livres para pastar M. tenuiflora e recebiam concentrado em quantidade equivalente a 1% do peso vivo. Após as primeiras chuvas, em meados de janeiro do ano seguinte, quando o estrato herbáceo apareceu, essas ovelhas foram confinadas em baias, onde M. tenuiflora foi fornecida até o fim do experimento. A cada 15 dias eram realizados exames ultrassonográficos para acompanhamento da gestação. No Grupo 1, três ovelhas abortaram, cada uma um feto sem malformações. Outra ovelha pariu dois cordeiros, um com hiperflexão na articulação inter-falangeana proximal no membro torácico direito e outro sem malformações. Outra ovelha pariu um cordeiro com hiperflexão dos dois membros pélvicos na região da articulação tarso-metatársica. No grupo formado pelas ovelhas que foram acasaladas na área experimental, uma ovelha abortou um feto sem malformações e cinco pariram cordeiros normais. Três das ovelhas desse grupo não emprenharam durante todo o período experimental, mostrando retornos repetidos ao cio, sugerindo perda embrionária. Trinta e duas ovelhas e um carneiro, que permaneceram numa área vizinha a área experimental e foram utilizados como controle, pariram cordeiros normais. Conclui-se que M. tenuiflora, além de causar malformações causa, também, mortalidade embrionária e abortos em ovelhas.

Cytotoxic effect of ICD-85 (venom-derived peptides) on HeLa cancer cell line and normal LK cells using MTT Assay.

Cancer is the fifth leading cause of death worldwide. There are considerable efforts to identify naturally occurring substances for use as new drugs in cancer therapy. Some components of animal venoms have been identified that possess substantial anticancer properties. In our previous studies, the cytotoxic effects of ICD-85 (venom-derived peptides) have been reported on HL-60 and MDA-MB231 cell lines. This has prompted us to investigate the comparative cytotoxic effects of ICD-85 on the HeLa cell line and normal lamb kidney (LK) cells. Cells were exposed to various concentrations (8 × 10-4 to 5.6 × 10 µg/ml) of ICD-85 at various incubation times (24, 48 and 72 hours). Cell viability was measured by the MTT assay. A morphological study was also carried out using an inverted microscope. Caspase-8 activity was assayed by the Caspase-8 Colorimetric Assay Kit in HeLa cells that were exposed to ICD-85 for 48 hours. Data analysis showed that ICD-85 has a dose-dependent cytotoxic effect on HeLa cells with an inhibitory concentration 50% (IC50) of 26.62 ± 2.13 µg/ml at 24 hours, 27.33 ± 2.35 µg/ml at 48 hours, and 28.13 ± 2.52 µg/ml at 72 hours. Results also indicated that the cytotoxic effect of ICD-85, at 48 and 72 hours incubation times did not show significant alteration compared to 24 hours of exposure. Interestingly, the minimum concentration of ICD-85 which showed a cytotoxic effect on LK cells was found to be 3500-fold less than the minimum concentration that showed a cytotoxic effect on the HeLa cancer cells. While morphological analysis revealed a significant difference that included the characteristic rounding of dying cells by treatment with ICD-85 compared with untreated HeLa cells, this difference was not observed in normal cells. ICD-85 increased caspase-8 activity in HeLa cells after 48 hours of exposure. ICD-85 has a dose-dependent cytotoxic effect on HeLa cancer cells in contrast with its negligible effect on normal LK cells.

An unusual cyclops kid associated with a normal twin from Kerman Province

A 3-year-old crossbred Pakistani doe in its second parturition was submitted to the private clinics in Kerman without a complaint of dystocia. She delivered a normal alive female lamb twin and a monster alive male. The gross examination revealed severity of the facial defects such as atypical cyclopia, involving the one eye with double lens, cornea, iris, and ciliary body. The history of herd revealed some congenital malformations previously.

Residual feed efficiency established in a post-weaning growth test may not result in more efficient ewes on the range

Reduction of feed required for normal lamb and wool production could improve the profitability of sheep producers. Our objectives were to determine growth and feed efficiency traits of Targhee sheep receiving a growing diet as ewe-lambs (Exp. 1) and a maintenance diet as yearlings (Exp. 2). Furthermore, we compared the repeatability of these traits between the two experiments. Within each experiment, residual feed intake (RFI) was strongly correlated (0.77 and 0.89) with DMI and no relationships were detected between RFI and ADG or metabolic BW. The low-RFI group had a 19 and 29% reduction in DMI compared to the high-RFI group for Exp. 1 and 2, respectively. No differences were detected for wool fiber diameter change (Exp. 1) or hay digestibility (Exp. 2) among RFI groups (P≥0.70). No significant correlations were detected for growth or feed efficiency traits between Exp. 1 and 2. These results suggest that considerable feed efficiency differences exist in ewe-lambs during active growth and yearlings at maintenance. However, based upon the lack of relationship between Exp. 1 and 2 for feed efficiency, the authors suggest that RFI established on a postweaning growth test may not result in more efficient ewes on the range.

First Report of a Cyclops Lamb Associated With a Normal Twin Lamb From Iran

A four- year-old Moghanian breed ewe was admitted to the large animal veterinary clinic, University of Tabriz due to dystocia. During obstetrical examination, it was revealed that the cervix has been closed firmly and vagina protruded about 5 cm through the vulva (vaginal prolaps). Based on clinical findings and for saving the dam and lamb(s), the cesarean section was done. A normal alive female lamb twin to a monster dead male was delivered. According to the facial deformity, the monster twin was diagnosed as Cyclops lamb. This is the first report of a Cyclops lamb’s giving birth twine to a normal lamb from Iran.

Enhancement technology improves palatability of normal and callipyge lambs

The objective of this research was to determine if BPI Processing Technology (BPT) improved palatability of normal (NN) and callipyge (CN) lamb meat and to determine the mechanism by which palatability was improved. Ten ewe and 10 wether lambs of each phenotype were slaughtered, and carcass traits were assessed by a trained evaluator. The LM was removed at 2 d postmortem. Alternating sides served as controls (CON) or were treated with BPT. Muscles designated BPT were injected to a target 120% by weight with a patented solution containing water, ammonium hydroxide, carbon monoxide, and salt. Muscle pH, cooking loss, Warner-Bratzler shear force (WBS), sarcomere length, cooked moisture retention, and desmin degradation were measured. A trained sensory panel and a take-home consumer panel evaluated LM chops. Callipyge had a heavier BW and HCW, less adjusted fat thickness, reduced yield grades, and greater conformation scores than NN (P < 0.05). For LM, NN had shorter sarcomeres, smaller WBS values, greater juiciness ratings, more off-flavors, reduced consumer ratings for raw characteristics (like of portion size, like of color, like of leanness, overall like of appearance) and greater consumer ratings for eating characteristics (like of juiciness, like of flavor) than CN (P < 0.05). For LM, BPT had greater cooked moisture retention, smaller WBS values, greater juiciness ratings, less off-flavors, and greater consumer ratings for raw characteristics (like of portion size, like of color, overall like of appearance) and eating characteristics (like of juiciness, like of flavor) than CON (P < 0.05). Significant phenotype × treatment interactions occurred for LM muscle pH, desmin degradation, tenderness, consumer like of texture/tenderness, and consumer overall like of eating quality (P < 0.05). For LM, BPT increased muscle pH more for NN than CN (P < 0.01) and increased desmin degradation for NN but decreased desmin degradation for CN (P < 0.01). The BPT enhancement improved LM tenderness ratings for CN more than NN (P < 0.05). For consumer like of texture/tenderness, BPT improved ratings for CN more than NN (P < 0.01). For consumer overall like of eating quality, BPT improved ratings for CN more than NN (P < 0.05). In summary, BPT had little to no effect on sarcomere length and desmin degradation, but improved palatability of NN and CN lamb by increasing cooked moisture retention, improving consumer acceptability of CN to near-normal levels.

The caspase proteolytic system in callipyge and normal lambs in longissimus, semimembranosus, and infraspinatus muscles during postmortem storage1

The objective of this experiment was to determine whether the caspase proteolytic system has a role in postmortem tenderization. Six ewes and 6 wethers that were noncarriers and 6 ewes and 6 wethers that were expressing the callipyge gene were used for this study. Caspase activities were determined in LM at 7 different time points during the postmortem storage period: 0 h, 4 h, 8 h, 24 h, 2 d, 7 d, and 21 d and in semimembranosus (SM) and infraspinatus (IS) muscles at 0 h, 8 h, 24 h, and 7 d from callipyge and noncallipyge (normal) lambs. Calpastatin activity was determined at 0 h, 2 d, 7 d, and 21 d and slice shear force measured at 2, 7, and 21 d in the LM. Calpastatin activity and slice shear force were greater in LM from callipyge lambs than normal lambs at each time point (P < 0.001 and P < 0.0001, respectively). Caspases 3 and 7 are executioner caspases, and their combined activity was found to decrease during the postmortem storage period in LM, SM, and IS muscles from callipyge and normal lambs. Similarly, activity of the initiator caspase (caspase 9) decreased (P < 0.05) in all 3 muscles across the postmortem storage period in callipyge and normal lambs, and its decrease in activity preceded that of the executioner caspases 3/7. A positive relationship also was detected between caspase 9 and caspase 3/7 in LM, SM, and IS muscles (P < 0.0001, r = 0.85, r = 0.86, r = 0.84, respectively), which is consistent with caspase 9 being responsible for the cleavage and activation of the executioner caspases (caspase 3/7) downstream. Caspase 3/7 and caspase 9 activities at 8 h in SM were greater in normal lamb than callipyge lamb (P < 0.05), with a trend for caspase 3/7 activity to be greater at 24 h postmortem (P = 0.0841). There also was a trend for caspase 3/7 activity to be greater in LM at 21 d in normal lamb than in callipyge lamb (P = 0.053), although there were no differences detected in caspase activities between genotypes in the IS muscle, which is not affected by the callipyge gene. A negative relationship also was detected between peak caspase 3/7 activity at 8 h in LM from normal lambs and calpastatin activity at 0 and 2 d (r = -0.65, r = -0.68, respectively, P < 0.05). This relationship was not observed in LM from callipyge lambs, suggesting that caspase 3/7 may be cleaving calpastatin in normal lambs but the level of calpastatin in callipyge lambs is such that caspase 3/7 cannot degrade it sufficiently to overcome the increased content of calpastatin, and thus, calpastatin activity is the overriding factor in postmortem proteolysis in these animals. There was no direct evidence from this study that caspases have a significant role in postmortem tenderization, but they may have some role through calpastatin degradation.

307 TRANSGENIC OVINE EMBRYOS BY ARTIFICIAL INSEMINATION, IN VITRO FERTILIZATION AND INTRACYTOPLASMIC SPERM INJECTION

Nowadays, transgenesis in animals constitutes an important tool for pharmacological protein production and livestock improvement. In 1971 Brackett first described that heterologous DNA can be introduced into a mammalian oocyte using sperm cells as vectors. We evaluated the capacity of AI, IVF and ICSI to produce transgenic embryos, in ovine, using sperm that had been exposed to a pCX-EGFP plasmid in Long and Short incubation protocols. The pCX-EGFP plasmid contains an enhanced green fluorescent protein gene (egfp) under the chimeric cytomegalovirus-IE-chicken β-actin enhancer-promoter control. Sperm/pCX-EGFP incubation was carried out by Long Incubation (2 h at 17°C in 200 μL of SFM medium: 100 mL contains glucose 1.2 g, Na citrate 1.0 g, EDTA 0.4 g, Citric acid 0.3 g, Trizma 0.6 g) and Short Incubation (5 min at 0–5°C in 10–100 μL of extender medium: 100 mL contains Na Citrate 2.8 g and EDTA 4 mg). For AI, Merino sheep (n = 17) were superovulated and inseminated with fresh semen (200 millions sperm/sheep) from eight Merino rams. The embryos were recovered by flushing the uterine horns by standard procedures. In IVF and ICSI, slaughterhouse oocytes were fertilized with frozen/thawed sperm. IVF was carried out in Brackett-Oliphant medium with 5 mm of caffeine, 20 IU mL–1 of heparin with 20 million sperm mL–1 during 5 h in an atmosphere of 5% CO2 in air. In ICSI, the spermatozoon was immobilized by breaking its tail and injected into MII oocytes. Immediately the oocytes were activated by incubation in TALP-HEPES with 5 μm ionomycin for 4 min, cultured in TCM199 for 3 h and transferred to a droplet of 1.9 mm DMAP for 3 h. Maturation and cultivation conditions were determined by standard operating procedures. All embryos were exposed to blue light (488 nm) to determine the percentage of morulae/blastocysts showing green fluorescence. Results are shown in Table 1. Statistical analysis was done by Fisher test. AI and IVF were able to produce a high percentage of morula and blastocyst stage, but were unable to produce transgenic embryos. In contrast, regardless of the sperm/plasmid incubation protocol, high percentages of transgenic morulae and blastocysts were always obtained by ICSI and the highest rate was achieved with Short Incubation (P &lt; 0.05). In order to demonstrate ICSI-Short incubation embryo viability, two-day-old non-selected fluorescence embryos (n = 45), were transferred into the oviducts of five surrogate mothers. Pregnancy was diagnosed at day 25 (2/5; 40%), and one normal female lamb was recently born (1/5; 20%). In conclusion, our results show that in ovine, ICSI seems to be the only method for producing transgenic embryos using sperm cells as vectors. In addition the offspring born confirm the viability of these embryos. Table 1.Development and fluorescence expression of ovine embryos

Experimental studies of laser excitation of normal acoustic waves in ferromagnetic metals at the curie temperature

Laser excitation of normal (Lamb) waves in ferromagnetic plates and the effect of magnetic phase transition on their main characteristics—amplitude, vibration frequency, and propagation velocity—are studied experimentally.

Defective γ-Glutamyl Carboxylase Activity and Bleeding in Rambouillet Sheep

A flock of Rambouillet sheep was examined because of increased lamb mortality caused by ineffective hemostasis at parturition. Neonatal-affected lambs presented with inadequate hemostasis at the umbilicus, pale mucus membranes, and markedly prolonged activated clotting time. Affected lambs had consistently prolonged 1-stage prothrombin times and activated partial thromboplastin times that supported a defect in the common pathway or defects in both the intrinsic and extrinsic pathway of the coagulation cascade. Decreased activity of vitamin K-dependent procoagulant factors II, VII, IX, and X in male and female lambs suggested either a defect of the hepatic enzyme gamma-glutamyl carboxylase, or vitamin K(1) 2,3 epoxide reductase. Affected lamb hepatic gamma-glutamyl carboxylase activity was markedly decreased compared with that of age- and sex-matched control lambs, while vitamin K(1) 2,3 epoxide reductase and glucose-6-phosphatase activities were similar between an affected and normal lamb. Subcutaneous vitamin K(1) supplementation did not increase vitamin K-dependent procoagulant factor activities in 3 lambs administered vitamin K(1) daily. These data confirm defective gamma-glutamyl carboxylase activity as the cause of impaired coagulation of sheep in this flock. This flock represents the only viable animal model of hereditarily defective gamma-glutamyl carboxylase activity.

Acoustic Emission in Wide Composite Specimens

Acoustic emission (AE) is an attractive technique for the structural health monitoring (SHM) of aerospace systems. To reach its full potential in this role a quantitative approach must be adopted to study damage mechanisms in composite materials. In this paper, some of the practical issues regarding acoustic emission testing in composites are addressed. A model describing Lamb wave propagation through plates is described and used to make phase velocity and attenuation measurements in both aluminium and carbon fibre reinforced plastic plates. Results are then implemented in the frequency domain to conduct an experimental study of normal incidence Lamb wave reflections. Comparisons are made with finite element analysis (FEA) models with good results.

Normal gestations and live births after orthotopic autograft of vitrified–warmed hemi-ovaries into ewes

The aim of this study was to evaluate the long-term outcome of autotransplantation of vitrified warmed hemi-ovaries into ewes. Six hemi-ovaries from six ewes aged 6 to 12 months were vitrified. After dissection of the medulla, the hemi-ovarian cortex was stored at -196 degrees C in liquid nitrogen. Four to six weeks after the first laparotomy, the left ovary was removed and the vitrified-warmed hemi-ovary was sutured. Plasma progesterone concentration increased in a regular manner in all ewes. Three pregnancies occurred, from which four lambs were born. The first delivery of a normal lamb occurred in February 2003. The second delivery of two normal lambs occurred in March 2003 (a 2.5 kg male and a 2.8 kg female). The last lamb had a normal delivery but had a malformation of the left leg and the oesophagus. This lamb died two months after delivery from pneumariae. Histological examination of the grafted vitrified ovaries showed few primordial and antral follicles. These three pregnancies in a ewe model may indicate that ovarian vitrification gives results as good as those from a slow cooling protocol in autograft. It is impossible to establish a link between the vitrification procedure and the malformation of the last lamb, and further studies are needed to evaluate the feasibility of ovarian vitrification.

Sensing properties of normal oscillatory modes of quartz plates

The responses (relative velocity variations Δv/v of normal (symmetric or asymmetric) Lamb and shear-horizontal modes of ST-cut quartz plates, whose thickness is comparable with the wavelength, is studied. Since modes of different orders n belonging to these two families have different propagation velocities vn, polarizations ui, and displacement distributions in depth H, they exhibit different responses to variations in the parameters of the plate (density, elastic moduli, thickness, and temperature) and to the loading of its surface by thin films (i.e., to surface adsorption). Results of numerical calculation of the responses to these parameters are corroborated by experiments on the effect of the plate temperature variation and the effect of adsorption of water vapor onto the plate surface.