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131.
S Scully V Maillo P Duffy AK Kelly MA Crowe D Rizos P Lonergan 《Reproduction in domestic animals》2013,48(6):888-892
The objective was to examine the effect of lactation on uterine involution in post‐partum dairy cows. Holstein primiparous cows were used (n = 19, mean age: 3.9 ± 0.1 years). At calving, cows were randomly assigned to one of two treatment groups, lactating (n = 11) or non‐lactating (i.e. dried off at calving, n = 8). Examination of the reproductive tract was carried out by ultrasonography twice weekly until week 7 post‐partum. Blood samples were collected twice weekly for the analysis of progesterone to indicate the resumption of cyclicity and metabolites indicative of energy status. Uterine involution was assessed in terms of size of the uterine horns, uterine body diameter and uterine fluid volume as assessed by the amount of non‐echogenic material measured by ultrasound and position of the uterus. Vaginal mucous score was taken on day 28 post‐partum for the assessment of uterine inflammation. Resumption of cyclicity (serum progesterone > 1 ng/ml) had occurred in both groups on average by day 21 post‐partum. Concentrations of non‐esterified fatty acids and beta‐hydroxybutyrate were higher, whereas concentrations of glucose, insulin and IGF‐1 were lower (p < 0.05) in lactating compared to non‐lactating cows. Lactating cows had a smaller mean uterine body diameter (p < 0.05) than non‐lactating cows from days 28 to 42 post‐partum (day 28: 20.2 ± 1.3 vs 24.9 ± 1.5 mm, respectively) and had a lower mean uterine fluid volume up to day 49 (p < 0.05). By day 49, there was no difference in uterine diameter (15.2 ± 1.8 vs 15.2 ± 1.6 mm) or uterine fluid volume (0.11 ± 0.38 vs 0.18 ± 0.46) between lactating and non‐lactating cows, respectively. Vaginal mucous score revealed no evidence of uterine inflammation in either group. In conclusion, while lactation induced significant alterations in metabolic status, it did not have a major effect on the rate of uterine involution as defined in this study. 相似文献
132.
Balbir Kour Shivanjali Kotwal Manoj K. Dhar Sanjana Kaul 《Russian Agricultural Sciences》2016,42(1):37-41
Plantago ovata, commonly called as the 'desert Indian wheat' is a cultivated and economically important plant of the genus Plantago, a large genus containing ~200 species. It yields Psyllium (Isabgol) which has several health benefits and applications in pharmaceutical, food and cosmetic industries. In view of the genetic uniformity, detection of variability has remained a challenge in this species as the plant lacks inherent variability and has a narrow genetic base. During the present study, Random amplified polymorphic DNA (RAPD) was used to determine genetic relationship and detect whatever little hidden variation exists in this species and some of its wild allies. Limited genetic variability was observed in P. ovata whereas; extensive genetic variability was seen in its wild allies. The genetic distances among different accessions of P. ovata and different species of Plantago, were used to generate a dendrogram. 相似文献
133.
Culyba EK Price JL Hanson SR Dhar A Wong CH Gruebele M Powers ET Kelly JW 《Science (New York, N.Y.)》2011,331(6017):571-575
N-glycosylation of eukaryotic proteins helps them fold and traverse the cellular secretory pathway and can increase their stability, although the molecular basis for stabilization is poorly understood. Glycosylation of proteins at na?ve sites (ones that normally are not glycosylated) could be useful for therapeutic and research applications but currently results in unpredictable changes to protein stability. We show that placing a phenylalanine residue two or three positions before a glycosylated asparagine in distinct reverse turns facilitates stabilizing interactions between the aromatic side chain and the first N-acetylglucosamine of the glycan. Glycosylating this portable structural module, an enhanced aromatic sequon, in three different proteins stabilizes their native states by -0.7 to -2.0 kilocalories per mole and increases cellular glycosylation efficiency. 相似文献
134.
An experiment was conducted to evaluate the effect of substituting different levels of hazelnut kernel oil meal (HKM) for soybean meal (SBM) in diets for broiler. A total of 450 one-day-old female Ross 308 broiler chicks were allocated randomly to three treatment groups of 150 birds each in a randomized design. Each treatment group consisted of five replicates each of 30 chicks. All diets (in mash form) were formulated to meet nutrient concentrations recommended for broilers. The experiment lasted for six weeks. In the experiment, an SBM control (SBM) diet was compared to two HKM diets, replacing 50 (50HKM) and 100% (HKM) of SBM protein, respectively. Body weight gain, feed intake and feed conversion ratio of broilers were adversely affected ( P < 0.05) by the HKM diets at 42 days of age. Broilers fed 50HKM and HKM had growth performances similar ( P > 0.05). The carcass yield and abdominal fat pads of birds fed diets with SBM were higher ( P < 0.05) than those of chicks fed the 50HKM and HKM diets. The edible inner organ weight of chicks fed diets with HKM was the heaviest ( P < 0.05). It is concluded that SBM cannot be replaced even up to 50% with HKM in commercial broiler diet. 相似文献
135.
Twenty-five day-old White Leghorn chickens were each infected orally with 500 (Group I), 1000 (Group II) and 2000 (Group III) infective eggs of Ascaridia galli and were killed 30 days after the infection. A high percentage of the infecting dose (6.5%) established as adult worms in the intestine of chickens receiving the lowest level of primary infection, but as the amount of primary infection given to birds increased, there was a significant fall in the percentage establishment of adult worms in the intestine. A similar pattern of worm establishment was shown by chickens of the same age and receiving similar levels of primary infections, but which were treated with betamethasone at a dose of 2 mg/kg body weight commencing 5 days before and continuing up to 15 days after the infection. Betamethasone-treated birds, however, showed more establishment of worms in the intestine, but lower weight gains in comparison to the birds which were not treated. Different levels of primary infections given, with or without treatment with betamethasone, had no effect on the sex ratio of the resultant male/female worm populations, which became established in almost equal numbers in the intestine of chickens. 相似文献