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Adult wethers (n = 750) were lot-fed for 13 days, 8 days or 3 days before a simulated voyage lasting 18 days to examine whether the period of lot-feeding affected the proportion of sheep that ate pelleted feed and their body weight change during simulated shipping. There was no significant difference in the proportion of non-feeders between treatment groups on days 7 and 14 of the voyage. Body weights were not significantly different between the treatment groups on days 14 and 18 of the voyage. Overall body weight loss, from the farm to the end of simulated shipping, was 4.08 kg (+/- 0.28, s.e.m.), 4.58 kg (+/- 0.28) and 4.51 kg (+/- 0.28) in sheep lot-fed for 13 days, 8 days and 3 days, respectively, and was not significantly different between treatments. It was concluded that lot-feeding for 13 days conferred no advantage in body weight or numbers of non-feeders compared with shorter periods in this study. 相似文献
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Genetic variability in meiotic gynogenetic muskellunge,Esox masquinongy (Mitchell), estimated from segregation of microsatellite alleles
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Benjamin J Reading Paul S Wills Roy C Heidinger Edward J Heist 《Aquaculture Research》2016,47(9):2705-2715
Muskellunge, Esox masquinongy, is an important recreational freshwater fish native to North America. Since muskellunge populations are often maintained through stocking efforts, advances in muskellunge reproductive technologies are of direct relevance to fishery enhancement. We evaluated the efficiency of inbreeding through induced meiotic diploid gynogenesis. Eggs from six female muskellunge were manually stripped and activated using ultra violet‐irradiated yellow perch, Perca flavescens, sperm. Hydrostatic pressure shocking regimes (48 263 kPa) were then applied to the eggs to prevent second polar body expulsion producing unambiguous meiotic gynogens. Six female dams and samples of 12–20 of their gynogenetic progeny were genotyped at seven polymorphic microsatellite loci. Chromosomal recombination frequencies of microsatellite loci based on retention of heterozygosity among gynogens ranged from 0.043 to 0.839 (0.576 ± 0.237). There were no statistical differences in recombination frequency among females at any of the loci. The average inbreeding coefficient (F‐value) ranged from 0.581 to 0.979, equivalent to three to fourteen generations of full‐sibling crosses respectively. The average F‐value overall was 0.712, equivalent to between five and six generations of full‐sibling crosses. Centromere map distances of the seven microsatellite loci ranged from 2.15 to 41.95 cM and meiotic gynogenesis was useful in eliminating heterozygosity at loci proximal to the centromere, but not distal. Since the age at maturity of female muskellunge is approximately 5 years, gynogenesis may pose an expeditious alternative to traditional breeding strategies for creation of homozygous pedigrees for some loci that may be outcrossed to introduce positive heterozygosity effects in the offspring. 相似文献
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Tamara B. Wills DVM rea A. Bohn DVM PhD DACVP Linda G. Martin DVM MS DACVECC 《Journal of Veterinary Emergency and Critical Care》2005,15(2):136-142
Objective: To present a case of clinical hypocalcemia in a critically ill septic dog. Case summary: A 12‐year old, female spayed English sheepdog presented in septic shock 5 days following hemilaminectomy surgery. Streptococcus canis was cultured from the incision site. Seven days after surgery, muscle tremors were noted and a subsequent low serum ionized calcium level was measured and treated. Intensive monitoring, fluid therapy, and antibiotic treatment were continued because of the sepsis and hypocalcemia, but the dog was euthanized 2 weeks after surgery. New or unique information provided: Low serum ionized calcium levels are a common finding in critically ill human patients, especially in cases of sepsis, pancreatitis, and rhabdomyolysis. In veterinary patients, sepsis or streptococcal infections are not commonly thought of as a contributing factor for hypocalcemia. Potential mechanisms of low serum ionized calcium levels in critically ill patients include intracellular accumulation of calcium ions, altered sensitivity and function of the parathyroid gland, alterations in Vitamin D levels or activity, renal loss of calcium, and severe hypomagnesemia. Pro‐inflammatory cytokines and calcitonin have also been proposed to contribute to low ionized calcium in the critically ill. Many veterinarians rely on total calcium levels instead of serum ionized calcium levels to assess critical patients and may be missing the development of hypocalcemia. Serum ionized calcium levels are recommended over total calcium levels to evaluate critically ill veterinary patients. 相似文献
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In each of three trials, 240 crossbred barrows weaned at 17 d of age (5.1 kg BW) were assigned to one of three experimental treatments based on light and heavy weight outcome groups. Experimental treatments were 1) wean-to-finish at 0.69 m2/pig and 15 pigs/pen; 2) wean-to-finish double-stocked at 0.35 m2/pig, 30 pigs per pen for 8 wk and then randomly split into two pens (either stayed in same pen or moved to new pen) for growth to slaughter at 0.69 m2/pig; and 3) nursery facility for 8 wk at 0.35 m2/pig and 15 pigs/pen followed by move to the same grow-finish facility housing wean-to-finish and double-stocked pigs and maintaining pen integrity. Beginning at 38 kg BW, diets were supplemented with either bacitracin methylenedisalicylate at 33 mg/kg to slaughter or tylosin at 44 mg/kg to 59 kg BW and 22 mg/kg thereafter. There were no trial x treatment interactions, even though there was considerable variation in health status among trials. At the end of the 56-d nursery period, wean-to-finish pigs weighed more than nursery (28.7 vs 27.7 kg; P = 0.071) and double-stocked pigs (28.7 vs 26.9 kg; P = 0.002), due to greater ADG (wean-to-finish vs nursery; P = 0.062; wean-to-finish vs double-stocked; P = 0.002) and greater ADFI (wean-to-finish vs nursery; P = 0.024; wean-to-finish vs double-stocked, P = 0.002). There was no effect of treatments (P > 0.1) on ADG, feed conversion, carcass lean percentage, or lean gain during the growing-finishing period. There was also no effect of treatment (P > 0.1) on ADG or ADFI from weaning to slaughter. There was no difference (P > 0.1) between bacitracin methylenedisalicylate and tylosin for ADG, feed conversion, carcass lean percentage, or daily lean gain. These data suggest that housing 5-kg weaned pigs in fully slatted growing-finishing facilities from weaning to slaughter was not detrimental to overall performance. In this experiment, dietary additions of bacitracin methylenedisalicylate or tylosin from 38 kg BW to slaughter weight resulted in similar growth performance. 相似文献
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Objectives To investigate the use of unguided bronchoalveolar lavage techniques in dogs without fibreoptic bronchoscopy, using an adapted single vascular catheter and a double-lumen catheter made from two single vascular catheters.
Animals Sixty-nine dogs were examined with the single-catheter technique and 110 dogs with the double-catheter technique.
Design A prospective study.
Procedure Sixty-nine and 220 samples, collected with the single catheter and the double catheter respectively, were examined cytologically Lungs of 69 dogs were examined grossly and histologically. Radiographic examination was performed on 11 dogs.
Results The double-catheter technique produced samples with significantly higher cellularity (P < 0.01) and fewer red blood cells (P < 0.01) than the single-catheter technique. Repeat samples collected with a double catheter were not significantly different (P > 0.01) in any value. A reference range for nucleated cell counts of 62 to 1210 – 106 /L was calculated from 57 clinically and histologically normal dogs. The major residual effects of the technique were localised pulmonary oedema, and alveolar distension with collapse and congestion of distant parenchyma. Thoracic radiographs revealed increased lung opacity for at least up to 7 h after the procedure.
Conclusions The cellularity of the bronchoalveolar lavage fluid obtained was adequate and sufficient fluid was retrieved when the single catheter was located in a proper position. However, the double catheter obtained better samples more quickly and easily, with less damage to the respiratory tract. 相似文献
Animals Sixty-nine dogs were examined with the single-catheter technique and 110 dogs with the double-catheter technique.
Design A prospective study.
Procedure Sixty-nine and 220 samples, collected with the single catheter and the double catheter respectively, were examined cytologically Lungs of 69 dogs were examined grossly and histologically. Radiographic examination was performed on 11 dogs.
Results The double-catheter technique produced samples with significantly higher cellularity (P < 0.01) and fewer red blood cells (P < 0.01) than the single-catheter technique. Repeat samples collected with a double catheter were not significantly different (P > 0.01) in any value. A reference range for nucleated cell counts of 62 to 1210 – 10
Conclusions The cellularity of the bronchoalveolar lavage fluid obtained was adequate and sufficient fluid was retrieved when the single catheter was located in a proper position. However, the double catheter obtained better samples more quickly and easily, with less damage to the respiratory tract. 相似文献