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51.
Thermal stress in cattle results in major decreases in dairy production and reproduction. A study was designed to evaluate
the influence of temporary cooling on pregnancy rate in Holstein heifers during summer heat stress. Estrus was synchronized
with two injections of prostaglandin (PG), administrated 11 d apart, and all heifers were housed in a shaded enclosed structure at the time of the second PG injection.
After estrus detection, heifers were randomly divided into three groups: Control (C; n = 30), Sprinkler (S; n = 30) or Sprinkler
and Fan (SF; n = 30). Rectal temperatures were measured 2.5 hours before AI, at the time of AI, and 1.5 and 3.5 hours after
AI. Group C heifers receive no further treatment, but heifers in S and SF groups were exposed to short-term cooling from 2
hours before until 2 hours after AI with a sprinkler (S) or sprinkler and a fan (SF), respectively. Estrus detection and AI
were performed by a single skilled technician; semen was from a bull of known fertility. Rectal temperature did not differ
among groups 2.5 hours before AI, but at the time of AI was lower (P < 0.05) in SF group (39.3 ± 0.0°C) than in S (39.5 ± 0.0°C)
and C (39.9 ± 0.1°C) groups which also differed (P < 0.05). At 1.5 and 3.5 hours after AI, rectal temperature remained lower
in SF group (38.9 ± 0.0 and 38.7 ± 0.0°C, respectively) than in the S (39.4 ± 0.0 and 39.2 ± 0.0°C, respectively) and C (39.3 ± 0.0
and 39.3 ± 0.0°C, respectively) groups, which no longer differed. Pregnancy rate following AI was higher (P < 0.05) in SF
group (56.7%) than in the C group (23.3%) with the S group (40%) intermediate and not different from either. The present study
results indicate that cooling of dairy heifers for a short time before and after AI, especially with sprinkler and fan, can
increase pregnancy rate during heat stress. 相似文献
52.
Shadi Sedgh-Gooya Mehran Torki Maryam Darbemamieh Hassan Khamisabadi Mohammad Amir Karimi Torshizi Alireza Abdolmohamadi 《Journal of animal physiology and animal nutrition》2021,105(1):119-128
This study was conducted to evaluate the effects of dietary Tenebrio molitor larvae meal (TM meal) inclusion on the performance, carcass traits, caecum microbiota and blood parameters of broiler chickens. A total of 180-day-old chickens were allocated to three dietary groups with five replicate pens (12 birds/pen). Experimental diets were included a corn-soybean basal diet, and two diets with 2.5% and 5% TM. TM-included diets have been administered for periods of starter (1–10 days) and grower (11–25 days). A regular finisher diet was given to all groups during the 26–42 days of age. Diets containing TM meal did not influence feed intake and mortality percentage. Feed conversion ratio was lower with the 2.5% TM meal diet compared with the control group at starter period (p < .05). Besides, broiler chickens fed TM meal included diet had a higher body weight gain than the control group during 1–10 days of age (p < .05). The carcass characteristics and length and weight of different parts of small and large intestines were not influenced by diets. TM meal inclusion decreased the albumin-to-globulin ratio compared with the control group (p < .05). Additionally, lower total count of aerobic and Escherichia coli bacteria was observed in response to diet inclusion of 5% TM meal. Overall, the inclusion of TM meal in broilers' diet improved body weight gain and feed conversion ratio in the starting period, decreased albumin-to-globulin ratio and E. coli bacteria content. 相似文献
53.
Amanlou H Karimi A Mahjoubi E Milis C 《Journal of animal physiology and animal nutrition》2011,95(5):616-622
The aim of this study was to investigate the effects of supplementation with digestible undegradable protein (DUP) in diet during late pregnancy on colostrum production, lamb survival and growth. For 3 weeks prior to lambing, 41 Afshari ewes were assigned at random to three dietary treatments, namely a control (CDUP), moderate (MDUP) and high (HDUP) DUP group. The ewes (n = 14) in CDUP group were fed a protein maintenance level for pregnant ewes [83 g metabolizable protein (MP)/kg dry matter (DM)], while ewes in the MDUP (n = 13) and HDUP (n = 14) groups were fed diets provided 14% (94.7 g MP/kg DM) and 24% (104.3 g MP/kg DM) MP in excess of these requirements respectively, which this increment was coming from DUP (DUP/MP ratio 43.8; 51.0% and 57.6% respectively). All diets were isoenergetic (12 MJ ME/kg DM). All ewes received the same lactation diet after lambing. Ewes in HDUP tend to produce more colostrums (p < 0.1) and had higher protein, fat, and solids non-fat content (p < 0.05) in colostrums during the first 24 h after lambing. MDUP group had higher colostrum yield compared to CDUP (p < 0.1). The changes in body weight and body condition score of ewes were similar for all diets but placenta weight was higher in MDUP group (p < 0.05) than for HDUP and CDUP ewes. Lamb body weight at weaning was higher for males compared to females (p < 0.05), but was not different between treatments. HDUP ewes had higher blood glucose concentration in the pre-lambing period than other treatments (p < 0.05). In this period, increasing the level of DUP in diet increased the content of blood urea nitrogen (p < 0.05). It was concluded that increasing the DUP content of diet for 3 weeks prior to lambing above the standard requirements resulted in an increase in colostrums production but had no effect on lamb outcome to weaning. 相似文献
54.
Rouhollah Karimi 《Journal of plant nutrition》2013,36(19):2666-2681
AbstractIn this research the effect of calcium sulfate (CaSO4; C1: 0%, C2: 1% and C3: 2%) combined to zinc sulfate (ZnSO4; Z1: 0%, Z2: 0.5% and Z3: 1%) was evaluated in commercial vineyard (Vitis vinifera cv “Sultana”) located in Jowzan Valley of Malayer city (Iran). Vines were sprayed two times in March, a week before bud wooly stage during two consecutive seasons, 2016 and 2017. The spring cold tolerance and some related physiological traits of vines were evaluated at three phenological stages of wooly bud, green tip and leaf emergence status. Application of CaSO4 and ZnSO4 in moderate level significantly delayed budbreak up to 9?day in compared to control vines. In green tip bud phenological stages, C2Z3 combined treatment showed the lowest LT50 (highest cold hardiness), although it did not significantly differ with obtained LT50 of C2Z2 treated vines. In green tip stage, higher glucose content was recorded in C2Z2 treatments. Fructose contents of C2Z2 treatment in wooly, green tip and leaf emergence stages approximately were 21%, 21%, 27% higher than control non-sprayed vines. In all three stages, vines sprayed with C2Z3 showed the highest putrescine concentration. In C2Z2 and C2Z3 treatments spermine and spermidine were higher compared to other treatments. In green tip stage also the vines treated with C2Z3 showed the highest abscisic acid (ABA) concentration in compared to other fertilizer treatments. The change pattern of gibberellins (GA) was in contrast with ABA change in buds during bud developmental stages and the always vines treated with C2Z2 or C2Z3 exhibited the lowest GA concentration and the control vines showed the highest amount of GA. In all sampling stages, vines treated with C2Z3 and C1Z1 (controls) having the least and highest endogenous auxin (IAA) in respectively. Altogether, data showed that calcium and zinc are highly efficient for spring frost tolerance increase in grapevine. 相似文献
55.
Khosro Mohammadi Asad Rokhzadi Seyed Farhad Saberali Motalleb Byzedi Mohammad Tahsin Karimi Nezhad 《Archives of Agronomy and Soil Science》2013,59(12):1625-1641
Information regarding the evaluation of tillage effects on soil properties and rainfed wheat (Triticum aestivum L.) cultivars of Iranian fields is not available. Therefore, this research was conducted in Sanandaj (west of Iran) using a randomized complete block design in a split-plot arrangement. Three types of tillage including conventional tillage (moldboard plow to soil depth of 30 cm plus disk harrow twice), minimum tillage (chisel plow to soil depth of 15 cm plus disk harrow once) and no-tillage are assigned to the main plots. Wheat cultivars (Sardari and Azar2) were randomly distributed within the subplots in each tillage system. Results showed that the greatest bulk density and cone index were found in the minimum tillage and no tillage systems. The highest rate of grain yield was obtained in the minimum tillage system. The grain yield of Sardari cultivar (1624.1 kg ha?1) was significantly greater than that of Azar2 (1572 kg ha?1). Minimum tillage improved soil physical properties and wheat growth compared with the other tillage systems. No tillage increased microbial biomass carbon and bacteria number in soil compared with the other tillage systems. We conclude that using minimum tillage for Sardari cultivar will be more effective compared with other treatments. 相似文献
56.
Khosro Mohammadi Gholamreza Heidari Mohsen Javaheri Mohammad Tahsin Karimi Nezhad 《Archives of Agronomy and Soil Science》2013,59(7):899-910
Tillage systems and fertilization have important effects on soil microorganism activity. Information regarding the simultaneous evaluation of long-term tillage and fertilization on soil microbial traits in sunflower fields is not available. Therefore, this study was conducted to determine the best tillage and fertilization system for soil microbial parameters. The experimental design was a split plot based on a randomized complete block design with three replications. Main plots consisted of the long-term tillage systems (1999–2011) including: no tillage (NT), minimum tillage (MT) and conventional tillage (CT). Six methods of fertilization, including farmyard manure (N1), compost (N2), chemical fertilizers (N3), farmyard manure + compost (N4); farmyard manure + compost + chemical fertilizers (N5), and control (N6) were arranged in subplots. Results showed that the highest amount of microbial biomass was observed in treatment NTN4. The highest and lowest values of enzyme activities (acid, alkaline phosphatase, urease, dehydrogenase and protease) were found in organic fertilizers + NT and chemical fertilizers + CT plots, respectively. Highest basal and induced respiration values were found for NTN4 treatment. Correlation coefficients between enzyme activity, respiration and microbial biomass carbon were significant. 相似文献
57.
In this paper the peculiar shape memory property of semicrystalline PET films is studied. The shape memory samples were prepared through isothermal crystallization of glassy PET films at different temperatures between 120 and 230 °C for 15 and 4 minutes. It was assumed that the incorporated shape memory constitution is due to crystalline and amorphous parts and also third phase i.e. a rigid amorphous fraction (RAF) which rose by increasing the degree of crystallinity. The microstructure of samples was probed by DSC and WAXD analysis, and concluded that isothermal crystallization at temperature which spinodal decomposition mechanism is dominant, brings the formation of secondary crystal lamellas in amorphous regions between pre-existing lamellar stacks, incorporating shape recovery in the samples. As the crystallization proceeds with time or at higher temperatures, the fraction of RAF increases leading to suppression of shape memory effect. 相似文献
58.
Danay Carrillo Nieves Keikhosro Karimi Ilona Sárvári Horváth 《Industrial Crops and Products》2011,34(1):1097-1101
Oil palm empty fruit bunches (OPEFB), a waste lignocellulosic material, which is the main byproduct of vegetable oil production industries in Indonesia and Malaysia, was utilized as a source for biogas production. Pretreatments using NaOH as well as phosphoric acid were investigated to improve the biogas production. Clear positive effects of the pretreatments on the yield of methane were observed. The best improvement was achieved when 8% NaOH for 60 min was used for the pretreatment, which resulted in 100% improvement in the yield of methane production. In addition, treatment with phosphoric acid resulted in 40% improvement in the methane yield compared with that of the untreated material. The results showed that the carbohydrate content of OPEFB could be efficiently converted to methane under the anaerobic digestion process. 97% of the theoretical value of methane production was achieved after the pretreatment with NaOH for 60 min. Moreover, the initial rate of methane production was also increased by more than 85% after the treatment with NaOH compared with that of the untreated OPEFB. 相似文献
59.
Spermiation time affect the milt quality indices of the Russian sturgeon,Acipenser gueldenstaedtii,Brandt & Ratzeburg, 1833 下载免费PDF全文
Mostafa Halimi Asma Mohammadi Rouhallah Norousta Hossein Khara Mohammad Reza Karimi 《Aquaculture Research》2015,46(10):2426-2430
In this study, the effects of spermiation time are investigated on milt quality of Russian sturgeon over the course of the spawning season. The milt samples were collected from three broodstock batches at three time points including: the beginning, middle and at the end of the spawning season. According to the results, the milt quality parameters including pH, sperm density, spermatocrit, duration of sperm motility and percentage of sperm motility were significantly low in the beginning and end of season than middle of season. The values of milt quality parameters in the middle of season were as follows: (motility percentage: 69.6 ± 3.5, motility duration: 460.3 ± 37.2 s, sperm density: 8.7 ± 0.4 × 109, milt volume: 86.3 ± 8.1 and milt pH: 8.3 ± 0.15). Significant positive correlations were also found between milt pH and sperm motility as well as between sperm density and spermatocrit. In conclusion, our study showed that the middle of season is the best time for collection of milt with appropriate quality in Russian sturgeon. Selection of milt with good quality is necessary aim to cryopreservation of spermatozoa in endangered fish species including Russian sturgeon. 相似文献
60.
Sana Eybpoosh Yeganeh Talebkhan Samaneh Saberi Maryam Esmaeili Akbar Oghalaie Fatemeh Ebrahimzadeh Toktam Karimi Afshin Abdirad Azin Nahvijou Mohammad Ali Mohagheghi Mahmoud Eshagh Hosseini Marjan Mohammadi 《Iranian Biomedical Journal》2015,19(3):133-142