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The status of the mare and foetus in relation to readiness for birth was assessed by measurement of the electrolytes sodium, potassium and calcium in mammary secretions pre-partum. Sixteen Thoroughbred mares were allowed to foal spontaneously and the ionic status of their mammary secretions was measured over three to five weeks pre-partum. From these measurements, a scoring system was developed where an ionic score of 35 points or more suggested that the mare was within 24 h of foaling. On the basis of this ionic score, 10 pony mares were induced with either oxytocin or fluprostenol and assessment of foal maturity was made by physical, behavioural and physiological criteria. Eight pony mares, induced when the ionic score was 35 points or more, delivered full term foals; two mares were induced when their scores were 30 and 20 points and delivered a full term and slightly immature foal respectively. These results suggest that foetal maturity may be related to electrolyte concentrations in mammary secretions and that an ionic score of 35 points or more may indicate that induction would be successful in terms of maturity of the newborn foal.  相似文献   
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The aim of this work was to examine the influence of the cumulus and gonadotropins on the metabolic profile of porcine cumulus oocyte complexes (COCs) during in vitro maturation. Immature COCs were assigned to morphological classes A1 (with a dense cumulus), A2 (with a translucent cumulus), B1 (with the corona radiata), B2 (with only some remaining cumulus cells) and matured with or without gonadotropins. Glycolysis and ammonia production were higher in the A class COCs; gonadotropins increased both, especially in the A1 COCs (p < 0.05). The A class COCs had the highest initial protein contents and at the end of in vitro maturation. Furthermore, hormonal stimulation induced a similar increase in protein contents of both A classes (p < 0.05). The neutral lipid content and reactive oxygen species (ROS) levels were similar in the immature oocytes of the COCs of all classes. A reduction was seen in both these variables when maturation proceeded either in the presence or absence of gonadotropins. The cumulus type surrounding the oocyte is related to the metabolism of carbohydrates and amino acids by the COC during in vitro maturation under gonadotropic stimulation. Oocyte lipolytic activity and ROS production appear to be independent of the surrounding cumulus and the presence of gonadotropins.  相似文献   
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Consumption of fresh apple fruits can induce allergic reactions in humans. The apple allergen Mal?d?1 is responsible for these allergic reactions in humans in Central Europe and North America. Biosynthesis of Mal?d?1 depends on apple cultivar, and its concentration increases with time during fruit storage. However, data on the impact of different fruit storage conditions during long-term storage are scarce. Hence, the Mal?d?1 contents of eight apple cultivars were analyzed for this study during long-term storage in a cold chamber as well as under controlled atmosphere conditions (CA). After harvest, apple fruits were stored for 12, 20, 28 or 36 weeks in a cold-chamber at +?2?°C or as under controlled atmosphere conditions of 1.5?% CO2, 1.5?% O2 at +?2?°C. Mal?d?1 content in apple fruit of all eight cultivars examined increased during fruit storage. In most cases, differences between Mal?d?1 of apple fruits stored in the cold chamber and under CA conditions were significant, but inconsistent. In apple cv. ??Elise??, fruits stored in the cold chamber contained more Mal?d?1 compared with those stored in CA, whereas the situation reversed in other varieties like cv. ??Boskoop??. The greatest Mal?d?1 content was measured in fruits of cvs. ??Golden Delicious?? and ??Gala??, whereas the smallest Mal?d?1 level was in cvs. ??Elise?? and ??Pinova?? over the whole storage time. Overall, this experiment showed the complexity of the relationship between the Mal?d?1 content, allergenicity of apple fruits, different cultivars, storage conditions and storage time. Persons allergic to apple fruits should consume the fruits as fresh as possible or only after a limited storage time. Furthermore, they should prefer apple varieties with a low content of allergenic proteins, such as cv. ??Elise?? or cv. ??Boskoop?? as a cultivar known for its large polyphenol content.  相似文献   
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Aims: To provide herd managers with a set of decision rules allowing them to predict the likelihood that a juvenile bull is ready for Bull Breeding Soundness Evaluation (BBSE), or breeding, if bodyweight and scrotal circumference are known.

Methods: This was a longitudinal study following two groups of young pasture-fed Holstein and Jersey bulls from northwest Tasmania, Australia. Individual scrotal circumference, bodyweight and semen characteristics were recorded at 6–8 weekly intervals, from 6–18 months of age. Classification and regression tree analyses were used to predict the probability that a bull had ≥70% normal sperm morphology based on scrotal circumference and bodyweight measurements.

Results: Overall 1,661 scrotal circumference and bodyweight measurements were obtained, and 518 semen samples from 356 bulls were assessed for sperm morphology, from 16 examination sessions that took place between 29 May 2015 and 17 August 2016. Classification and regression tree analyses generated a decision tree for Holstein bulls with four node endpoints, and for Jersey bulls with three node endpoints. Diagnostic test performance showed that for Holstein bulls, using the node endpoints of scrotal circumference ≥27?cm and bodyweight ≥349?kg, 98% had ≥70% normal sperm (positive likelihood ratio 10.4; 95% CI?=?2.7–41), and using the node endpoints of scrotal circumference ≥27?cm and bodyweight between 282–349?kg, 89% had ≥70% normal sperm (positive likelihood ratio 1.6; 95% CI?=?0.9–2.6). For Jersey bulls, using the node endpoints of bodyweight ≥259?kg and scrotal circumference ≥29?cm, 88% had ≥70% normal sperm (positive likelihood ratio 3.4; 95% CI?=?1.6–7.0).

Conclusions: This study provides a set of relatively simple decision rules based on bodyweight and scrotal circumference measurements that allows herd managers to assess the likelihood that juvenile bulls are ready for BBSE or breeding.

Abbreviations: BBSE: Bull breeding soundness evaluation; BRT: Boosted regression tree  相似文献   

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Blood samples were collected from 69 ‘healthy’ female alpacas aged ≥12 months from 11 properties in South Australia. The 10–90 percentile ranges of the 16/19 analytes measured in this sample population were within the published ranges of four healthy alpaca populations from other geographic locations. Marginal exceptions were glutamate dehydrogenase and bicarbonate. Potassium was notably elevated, probably because of haemolysis of some samples. The sample size was insufficient to provide the appropriate statistical power to define diagnostic references ranges according to international standards. The health status of the sample population of alpacas was presumptive based on a physical examination.  相似文献   
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