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981.
Procedures are described for estimating selection index accuracies for individual animals and expected genetic change from selection for the general case where indexes of EBVs predict an aggregate breeding objective of traits that may or may not have been measured. Index accuracies for the breeding objective are shown to take an important general form, being able to be expressed as the product of the accuracy of the index function of true breeding values and the accuracy with which that function predicts the breeding objective. When the accuracies of the individual EBVs of the index are known, prediction error variances (PEVs) and covariances (PECs) for the EBVs within animal are able to be well approximated, and index accuracies and expected genetic change from selection estimated with high accuracy. The procedures are suited to routine use in estimating index accuracies in genetic evaluation, and for providing important information, without additional modelling, on the directions in which a population will move under selection.  相似文献   
982.
High‐yielding dairy cows are struggling with a high incidence of embryonic loss, among others caused by an insufficient peripheral progesterone concentration which for its part might be associated with an impaired luteal progesterone production. This impaired capacity to produce progesterone might be reflected in the histology of the gland. The aim of the present pilot study was the assessment of the variation in cell density within a bovine luteal gland (LG), to examine whether it is possible to analyse histologically the functionality of the gland based on one single tissue sample. Six LGs (stage II or III) were harvested out of just as many healthy cows at the slaughterhouse. The luteal cell density was assessed by calculating the nuclear density (ND) of the different luteal cell types on haematoxylin‐eosin‐stained histological sections from a number of topographic regions evenly spread throughout the glands, to give an overview of the pattern of cellular distribution within the whole gland. Cells were differentiated into ‘large luteal cells’, ‘small luteal cells’ and ‘non‐steroidogenic cells’. Results show that the cellular density, within a tissue sample is not significantly influenced by its location in relation to the gland's equatorial plane. However, the position with respect to the polar axis of the gland has a decisive effect, as the ND is significantly higher (p < 0.05) in the peripheral regions (outer zone) when compared with the central regions (inner zone) of the gland, and this counts for all three cell types.  相似文献   
983.
Oral malignant melanoma (OMM) in the dog is often locally aggressive with a high metastatic potential and there are few treatment options that have been demonstrated to improve outcome of this disease. The purpose of this study was to determine whether adjunctive treatment with the Oncept melanoma vaccine affected the outcome of dogs with OMM that had achieved loco‐regional cancer control. Medical records from 45 dogs that presented to the Animal Cancer and Imaging Center were reviewed, including 30 dogs with stage II and III disease. Dogs that received the vaccine did not achieve a greater progression‐free survival, disease‐free interval or median survival time than dogs that did not receive the vaccine.  相似文献   
984.
In 2008, two deer hunters in Virginia and Connecticut were infected with a unique strain of pseudocowpox virus, a parapoxvirus. To estimate the prevalence of this virus, and in an attempt to define the reservoir, Parapoxvirus surveillance was undertaken between November 2009 and January 2010. 125 samples from four ruminant species (cows, goat, sheep and white‐tailed deer) were collected in Virginia, and nine samples from white‐tailed deer were collected in Connecticut. We found no evidence that the parapoxvirus species that infected the deer hunters is circulating among domesticated ruminants or white‐tailed deer. However, parapoxvirus DNA of a different parapoxvirus species, bovine papular stomatitis virus (BPSV), was detected in 31 samples obtained from asymptomatic cattle in Virginia. Parapoxvirus DNA–positive cattle originated from the same counties indicating probable transmission among animals. Molecular analysis identified BPSV as the parapoxvirus affecting animals. Asymptomatic parapoxvirus infections in livestock, particularly young animals, may be common, and further investigation will inform our knowledge of virus transmission.  相似文献   
985.
The journal     
Extract

At the Annual General Meeting of the New Zealand Veterinary Association in 1951 a motion was carried “that this meeting recommend that a journal be started, and ask Council to investigate the matter from all aspects, and to report to the next Annual General Meeting.” To implement the wishes of the meeting, Council appointed a subcommittee which reported to the Annual General Meeting of 1952. The report, after dealing with costs and publishable material, recommended as follows:—  相似文献   
986.
Abstract

Extract

Following the occurrence in the field of typical cases of hyperkeratosis (Haughey and Cooper, 1953 Haughey, K. G. and Cooper, B. S. 1953. N.Z.vet.J., 1: 99103. [Taylor &; Francis Online] [Google Scholar]) which was associated with the use of a pentachlorinated naphthalene wood preserving compound, it was decided to attempt to reproduce this disease under experimental conditions.  相似文献   
987.
The aim of this study was to investigate the effects of melatonin and follicle-stimulating hormone (FSH) on the in vitro culture of goat preantral follicles. Ovarian fragments were cultured for 7 d in α-minimum essential medium (α-MEM+) containing melatonin (100, 250, 500, or 1,000 pM), FSH (50 ng/mL), or a combination of the 2 hormones and further analyzed by histology and transmission electron and fluorescent microscopy. The results showed that after 7 d of culture, tissues cultured in α-MEM+ alone or supplemented with FSH alone, melatonin (500 and 1,000 pM), or the combination of FSH and melatonin (1,000 pM) maintained percentages of normal preantral follicles similar to the fresh control. In contrast to the noncultured tissues, the percentage of developing follicles was increased under all culture conditions after 7 d (P < 0.05). The addition of 1,000 pM melatonin associated with FSH to the culture medium increased follicular and oocyte diameters compared with α-MEM+ alone after 7 d of culture (P < 0.05). Ultrastructural and fluorescent analyses confirmed the integrity of follicles cultured with 1,000 pM of melatonin plus FSH for 7 d. In conclusion, this study demonstrated that the interaction between melatonin and FSH maintains ultrastructural integrity and stimulates further growth of cultured caprine preantral follicles.  相似文献   
988.
Extant colobines represent a predominantly arboreal primate radiation, but there are outliers such as some species of snub‐nosed monkeys (Rhinopithecus spp.) that utilize both arboreal and terrestrial substrates. We quantified the degree of terrestriality and the distribution of individuals across canopy levels, the extrinsic and intrinsic determinants and constraints of strata association as well as use of postures in relation to behavior and food sources in a wild population of Yunnan snub‐nosed monkeys (Rhinopithecus bieti) in the Samage Forest, China. The subjects spent 80.5% of the observation time in the trees and 19.5% on the ground. Ground use occurred most frequently in the context of travelling (61%) and less often in the context of feeding and resting (30% combined). Adult males frequented the ground significantly more often than other age‐sex classes. Age‐sex differences were also apparent in substrate preferences, which likely reflect body weight constraints. Adult males were significantly more associated with solid substrates and less with terminal branches than adult females and juveniles. Juveniles were seen more often on unstable ground (i.e. on thin and oblique branches) and in the upper canopy. Substrate use also varied with behavior: feeding was much more common in the upper stratum, outer canopy, on highly inclined and thin branches, as compared to resting. Severe weather also influenced canopy use in that tree crowns were used less often during periods of snowfall. The most frequently exhibited resting and feeding postures was sitting. Standing and suspensory postures were most often used in the context of feeding on lichens.  相似文献   
989.
990.
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