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Cull dairy cows contribute almost 10% of national beef production in the United States. However, different factors throughout the life of dairy cows affect their weight and overall body condition as well as carcass traits, and consequently affect their market price. Therefore, the objectives of this study were: (1) to assess relationships between price ratio and carcass merit of cull dairy cows sold through several sites of an auction market and (2) to investigate the effect of animal life history events and live weight on sale barn price (BP) and price ratio (as a measure of relative price), as an indicator of carcass merit. Data from 4 dairy operations included 3,602 cull dairy cow records during the period of 2015 to 2019. Life history events data were collected from each dairy operation through Dairy Comp software; live weight and price were obtained periodically from the auction market, and the carcass data were provided by a local packing plant. Cow price in dollars per unit of live weight ($/cwt) and price ratio were the 2 outcome variables used in the analyses. Price ratio was created aiming to remove seasonality effects from BP (BP divided by the national average price for its respective month and year of sale). The association between price ratio and carcass merit traits was investigated using canonical correlation analysis, and the effect of life history events on both BP and price ratio was inferred using a multiple linear regression technique. More than 70% of the cows were culled in the first 3 lactations, with an average live weight of 701.5 kg, carcass weight of 325 kg, and dressing percentage of 46.3%. On average, cull cows were sold at $57.0/cwt during the period considered. The canonical correlation between price ratio and carcass merit traits was 0.76, indicating that price ratio reflected carcass merit of cull cows. Later lactations led to lower BP compared with cows culled during the first 2 lactations. Injury, and leg and feet problems negatively affected BP. Productive variables demonstrated that the greater milk production might lead to lower cow prices. A large variation between farms was also noted. In conclusion, price ratio was a good indicator of carcass merit of cull cows, and life history events significantly affected sale BP and carcass merit of cull cows sold through auction markets.  相似文献   
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In this study, we compare the development of infection and/or disease in Beagle dogs intradermally infected with Leishmania chagasi, in the presence or absence of Lutzomyia longipalpis saliva, with those of intravenously infected animals.Spleen samples of all the animals inoculated with parasites had positive polymerase chain reaction tests for Leishmania DNA. Positive spleen cultures for Leishmania were detected earlier (P < or = 0.018) and were more frequent (five out of the five animals) in intravenously infected animals than in the intradermally infected animals, in presence (two out of the six animals) or absence (three out of the five animals) of salivary gland lysate of L. longipalpis. Significant increase in serum antibodies against Leishmania was observed only in the intravenously infected group (P = 0.004). In addition, dogs with infection confirmed by isolation of amastigotes or detection of parasite DNA were, nevertheless, negative for anti-Leishmania antibodies up to 5 months or more after infection. Only animals of the intravenously infected group developed progressive decreases in hematocrit (Pearson r = -0.8076, P = -0.0026) and hemoglobin (Pearson r = -0.8403, P = 0.0012) during the infection period. No significant difference in the course of infection was observed between groups of intradermally infected animals. The data presented herein confirms that the intradermal inoculation of dogs with Leishmania produces an asymptomatic form of infection. It also fails to show an advantage in using L. longipalpis saliva as an infection-enhancing agent in experimental canine leishmaniasis.  相似文献   
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While much is known about the metabolism of exogenous nutrients such as glucose, lactate, pyruvate, amino acids by oocytes and pre-implantation mammalian embryos, the role of endogenous stores, particularly lipid, has been largely overlooked. The presence of lipid within oocytes and early embryos has been long known, and comparisons between species indicate that the amounts and types of lipid present vary considerably. Large amounts of intracellular lipid can compromise the success of cryopreservation and the removal of such lipid has been the subject of considerable effort. In this review, we present evidence that strongly suggests a metabolic role for lipid, specifically with regard to energy provision, in the late-stage oocyte and the pre-implantation embryo. We focus initially on oxygen consumption as a global indicator of metabolic activity, before reviewing different approaches that either have been designed to investigate directly, or have revealed indirectly the role of endogenous lipid in energy generation. These fall under five headings: (i) fatty acid oxidation; (ii) inhibition of triglyceride oxidation; (iii) culture in the absence of exogenous substrates; (iv) cytoplasmic organization; and (v) delipidation. On the basis of the data derived from these studies, we conclude that there is strong evidence for the utilization of endogenous lipid as an energy substrate by oocytes and early embryos.  相似文献   
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Lead an cadmium conditions of Berlin soils Pleistocene sediments of Berlin contain 10 mg/kg Pb and 0.1 mg/kg Cd, but debris of the city 80 mg/kg Pb. The topsoils are enriched with 60–100 mg/kg of anthropogenous Pb, near roads more than 200 mg/kg, and with 0.3–0.6 mg/kg Cd. Only low quantities of both elements were soluble in NH4-acetate, but half of the polluted elements was extractable with AEDTA, the unextractable part being enriched in the clay fraction. Exchange experiments show very high sorption rates of soluble lead, but in case of cadmium sorption was much lower so that this element can percolate especially sandy acid soils with low humus contents in higher amounts.  相似文献   
37.
This paper reports on two cases of laparoscopic nephrotomy employed in the treatment of canine dioctophymosis, which is considered a unusual procedure and a new treatment proposal heretofore not performed in veterinary medicine. Two patients were treated, one with a history of hematuria and the other with incidental finding of the parasite in the abdominal cavity during elective ovariohysterectomy. Both dogs were subjected to abdominal ultrasound, which produced images indicating the presence of the parasite in the right side kidney, but with partial parenchymal preservation. The patients were therefore subjected to laparoscopic nephrotomy. The surgical procedure was effective in treating dioctophymosis and enabled minimum tissue invasion during surgery, in addition to preservation of the kidney.  相似文献   
38.
A transvaginal ultrasound-guided intrauterine injection (IUI) technique was developed for embryo transfer and for injection of small quantities of sperm in mares. The target area of a horn was positioned by transrectal manipulation against the wall of the vaginal fornix over the face of a transvaginal transducer. A needle with a catheter containing the embryo or semen was inserted through the needle guide of the transducer into the uterine lumen. The tips of the needle and catheter, the movement of the catheter in the uterine lumen, and the ejection of fluid was monitored on the ultrasound screen. Pregnancy rate 15 days after ovulation for the IUI embryo transfer technique (30/39, 77%) was similar to the pregnancy rate for transcervical (TC) embryo transfer (30/38, 79%). The pregnancy rate for IUI insemination of 20 × 106 progressively motile sperm into the tip of the uterine horn ipsilateral to ovulation was 5/10 (50%). Results indicated that the IUI approach is a viable alternative for embryo transfer. Results also supported the potential of IUI for insemination of low numbers of sperm, but more extensive studies with various doses of sperm are needed.  相似文献   
39.
New Forests - The forestry sector has been able to sustainably satisfy the increasing global demand for forest products, thereby positively impacting the economy, while mitigating climate change....  相似文献   
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