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111.
The effect of goat nutritional condition on the response to biostimulation with sexually active males during different stages of anestrus was determined. Fifty‐eight Criollo × Nubian females on high and low body mass index (BMI) diets were used. Each BMI group was divided into two for biostimulation with sexually active males during May (mid‐anestrus) or July (transition period). Ovulatory responses to biostimulation were characterized from serum progesterone, as well as the delay for response (first and second ovulations followed by a normal length luteal phase, O‐WNLP). The percentage of goats showing one O‐WNLP was greater in the high BMI group than in the low BMI group and greater during the transition period than in the mid‐anestrus. However, the interaction between factors revealed that the difference between BMI groups was only significant in the transition period and the difference between stages was only significant in goats with high BMI. Occurrence of a second O‐WNLP tended to be greater in the high BMI group than in the low BMI group. Response delay was shorter in the transition period than in mid‐anestrus. In conclusion, female nutritional status interacting with the stage of anestrus determined the ovulatory response to male biostimulation in crossbred Criollo goats.  相似文献   
112.
A 13‐year‐old miniature horse mare presented for evaluation of ascites. Abdominal ultrasound showed severe free peritoneal fluid accumulation as well as a caudal abdominal mass. The peritoneal fluid was characterised as a transudate with no evidence of sepsis. Surgical exploration of the abdomen was performed; copious free peritoneal fluid and a large right ovarian mass were discovered. The abnormal ovary was removed, and the mass was determined histologically to be a benign granulosa theca‐cell tumour. Although there was mild peritoneal fluid accumulation in the immediate post operative period, the ascites effectively resolved with removal of the tumour, and the mare returned to a normal lifestyle. This is similar to reports of Meigs' syndrome in human women, in which a benign ovarian mass of significant size causes ascites that resolves once the mass is removed.  相似文献   
113.
The objective of the experiment was to compare the use of a PGF2α analogue (Cloprostenol) IM, with an intravaginal progestagen sponge, flurogestone acetate (FGA), and equine chorionic gonadotropin (eCG) IM application protocol. A total of 30 cyclical hair ewes (54.07?±?0.5 kg live weight, body condition score 3.5?±?0.5, and age 3?±?1 years) were used. For the control group ewes (n?=?15), intravaginal sponges (IS) impregnated with 20 mg of FGA were inserted for 12 days with 500 IU of eCG IM at sponges withdrawal. For the PG group ewes (Treatment group n?=?15), two injections of Cloprostenol (75 mcg) were given 12 days apart. The presence of estrus was detected using two rams with 8 h interval beginning at the end of the treatment. Progesterone concentrations in blood were measured by solid phase radioimmunoassay. A student’s t test was performed to analyze the duration of estrus and the interval between the ends of the treatment and the onset of estrus (ET-OE) presentation. Progesterone levels were compared with two-way ANOVA, with treatment, and day of menstrual cycle as fixed factors. Treatment costs ratio was calculated by dividing the total costs of FGA IS application between total costs of Cloprostenol application. Significant differences (P?P?相似文献   
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115.
Modern animal scientists, industry, and managers have never faced a more complex world. Precision livestock technologies have altered management in confined operations to meet production, environmental, and consumer goals. Applications of precision technologies have been limited in extensive systems such as rangelands due to lack of infrastructure, electrical power, communication, and durability. However, advancements in technology have helped to overcome many of these challenges. Investment in precision technologies is growing within the livestock sector, requiring the need to assess opportunities and challenges associated with implementation to enhance livestock production systems. In this review, precision livestock farming and digital livestock farming are explained in the context of a logical and iterative five-step process to successfully integrate precision livestock measurement and management tools, emphasizing the need for precision system models (PSMs). This five-step process acts as a guide to realize anticipated benefits from precision technologies and avoid unintended consequences. Consequently, the synthesis of precision livestock and modeling examples and key case studies help highlight past challenges and current opportunities within confined and extensive systems. Successfully developing PSM requires appropriate model(s) selection that aligns with desired management goals and precision technology capabilities. Therefore, it is imperative to consider the entire system to ensure that precision technology integration achieves desired goals while remaining economically and managerially sustainable. Achieving long-term success using precision technology requires the next generation of animal scientists to obtain additional skills to keep up with the rapid pace of technology innovation. Building workforce capacity and synergistic relationships between research, industry, and managers will be critical. As the process of precision technology adoption continues in more challenging and harsh, extensive systems, it is likely that confined operations will benefit from required advances in precision technology and PSMs, ultimately strengthening the benefits from precision technology to achieve short- and long-term goals.  相似文献   
116.
BACKGROUND: Parthenogenetic clones of the green peach aphid, Myzus persicae (Sulzer), and the cotton aphid, Aphis gossypii Glover, were tested with the anthranilic diamide insecticide cyantraniliprole (i.e. DuPont? Cyazypyr?) in systemic‐uptake bioassays to investigate potential for cross‐resistance conferred by mechanisms of insecticide resistance to organophosphates, carbamates and pyrethroids and, in the case of M. persicae, reduced sensitivity to neonicotinoids. These data were compared with the response of field samples of M. persicae and A. gossypii collected from around Europe. RESULTS: Cyantraniliprole was not cross‐resisted by any of the known insecticide resistance mechanisms present in M. persicae or A. gossypii. The compound was equally active against resistant and susceptible aphid strains. The responses of the M. persicae field samples were very consistent with a maximum response ratio of 2.9 compared with a standard laboratory clone. The responses of the A. gossypii field samples were more variable, although a majority of the responses were not statistically different. CONCLUSION: Cyantraniliprole is currently the only anthranilic diamide (IRAC MoA 28) insecticide targeting aphid species such as M. persicae and A. gossypii. There is no evidence to suggest that the performance of this compound is affected by commonly occurring mechanisms that confer resistance to other insecticide chemistries. Cyantraniliprole is therefore a valuable tool for managing insecticide resistance in these globally important pests. Copyright © 2011 Society of Chemical Industry  相似文献   
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