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21.
This study was carried out to determine the level of certain biochemical variables reflecting the energy metabolic statuses during the first week of lactation in goats. A total of 120 Anglo-Nubian, Angora, Baladi, and Damascus does (30 does per breed) were used throughout 5 consecutive parities (30 does per parity) to investigate the effect of breed, parity, day of lactation, and their interaction on serum metabolites including total protein, albumin, globulin, glucose, total lipids, cholesterol, and transaminases. Blood samples were collected every other day during the first week of lactation. Baladi does had the greatest (P < 0.001) values in all measured biochemical variables followed by Anglo-Nubian [in total protein, globulin, and aminotransferase (AST)] and Damascus (in globulin and AST) and then Angora, which had the lowest (P < 0.001) values for all variables. Fifth parity exhibited the greatest (P < 0.001) values in all serum metabolites compared with other parities except for alanine transaminase (ALT) enzyme activity in which the greatest (P = 0.046) values were observed in the first and fourth parties. Serum concentrations of the measured variables increased gradually throughout the first day after kidding until the seventh day for total protein (P < 0.001), albumin (P = 0.013), globulin (P = 0.017), and cholesterol (P = 0.028) whereas serum glucose concentration exhibited an opposite trend. Serum concentrations of total lipids and enzyme activities of AST and ALT were not affected by day (P > 0.05) after kidding. Baladi goats had the least (P < 0.001) serum insulin concentration, which was associated (P < 0.001) with greatest serum glucose concentration. Serum triiodothyronine (T(3)) was inversely correlated (P = 0.032) with milk yield whereas greatest (P = 0.003) T(3) concentrations were associated with least (P < 0.001) milk yield recorded in Angora goats. Animal physiological responses and their indices were not affected (P > 0.05) by breed whereas both rectal temperature and coefficient of heat tolerance were affected (P < 0.001) by parity in an opposite direction. Baladi goats expressed an aspect of adaptability where their rectal temperature decreased and coefficient of heat tolerance increased with increasing parity number.  相似文献   
22.
Contagious caprine pleuropneumonia (CCPP) caused by Mycoplasma capricolum subsp. capripneumoniae is a highly contagious and serious respiratory disease of domestic goats, characterized by coughing, severe respiratory distress, and high mortality rates. The lesions at necropsy are mainly a fibrinous pleuropneumonia with increased straw-colored pleural fluid. An outbreak of CCPP in wild goat (Capra aegagrus), Nubian ibex (Capra ibex nubiana), Laristan mouflon (Ovis orientalis laristanica), and gerenuk (Litocranius walleri) occurred at Al Wabra Wildlife Preservation in the State of Qatar. The disease was suspected because of the clinical symptoms and the necropsy findings and was confirmed by the isolation and identification of the causative organism. This new finding indicates that CCPP should be considered a potential threat to wildlife and the conservation of endangered ruminant species, especially in the Middle East, where it is enzootic because of its presence in chronic carriers. Susceptible imported animals should be quarantined and vaccinated. The preferred samples for diagnosis are the pleural fluid, which contains high numbers of Mycoplasma, and sections of hepatized lung, preferably at the interface of normal and diseased tissues. Samples must be shipped to diagnostic laboratories rapidly, and appropriate cool conditions must be maintained during shipping.  相似文献   
23.
This work aims to study the relationship between variations of the Temperature-Humidity Index (THI) and the parameters of reproduction especially the first conception rate (FCR) and to determine the threshold THI value where cows’ fertility rate dropped in 12 Holstein dairy herds raised in the arid climatic conditions of Tunisia. THI values were calculated over 22 years (1996–2018), and the mean monthly temperature and relative humidity data were obtained from the Meteorological Institute of Tunisia. A total of 20,396 individual records (Insemination and calving dates) were extracted from the Livestock and Pasturing Office (OEP, Tunisia) with regard to the highest THI before breeding, on the breeding day, and after breeding. Statistical analysis was performed using the GLM procedure of SAS software. Results point to the fact that a summer heat stress exists in southeast Tunisia and lasts for 4 months starting from June until September with THI values fluctuating between 73 ± 2.38 and 79 ± 3.01 exceeding, therefore, THI threshold of 72. Increased THI from ≤70 to ≥80 units was associated with drops in conception rate (CR) and fertility rate (FR) of 49% and 45% giving a correlation with the THI of (r = −.72, p < .05) and (r = −.74, p < .05), respectively. When cows were inseminated on extremely hot days (THI ≥ 80) preceded by cooler temperatures, pregnancy by service (P/AI) was 7% points higher than for other cows that were exposed to high temperatures before breeding. The average number of insemination was higher (p < .05) from THI ≤ 70 (2.01) compared to THI ≥ 80 (3.41). Cows calving during an absence of heat stress (THI ≤ 70) have the shortest average calving intervals (CI: 420 ± 15.1 days). Contrastly, calving in the condition of heat stress (THI ≥ 80) has the longest CI (487 ± 12.8 days). For each point increase in the THI value above 67, there is a decrease in the first conception rate by 1.39%. In this particular arid environment, high-yielding Holstein cows’ breeding success is strongly affected by heat stress that takes place just before or after breeding.  相似文献   
24.
Bovine respiratory disease is a complex of bacterial and viral infections of economic and welfare importance to the beef industry. Although tracheal antimicrobial peptide (TAP) has microbicidal activity against bacterial pathogens causing bovine respiratory disease, risk factors for bovine respiratory disease including BVDV and stress (glucocorticoids) have been shown to inhibit the induced expression of this gene. Lipopolysaccharide is known to stimulate TAP gene expression, but the maximum effect is only observed after 16 h of stimulation. The present study investigated other agonists of TAP gene expression in primary cultures of bovine tracheal epithelial cells. PCR analysis of unstimulated tracheal epithelial cells, tracheal tissue and lung tissue each showed mRNA expression for Toll-like receptors (TLRs) 1–10. Quantitative RT-PCR analysis showed that Pam3CSK4 (an agonist of TLR1/2) and interleukin (IL)-17A significantly induced TAP gene expression in tracheal epithelial cells after only 4–8 h of stimulation. Flagellin (a TLR5 agonist), lipopolysaccharide and interferon-α also had stimulatory effects, but little or no response was found with class B CpG ODN 2007 (TLR9 agonist) or lipoteichoic acid (TLR2 agonist). The use of combined agonists had little or no enhancing effect above that of single agonists. Thus, Pam3CSK4, IL-17A and lipopolysaccharide rapidly and significantly induce TAP gene expression, suggesting that these stimulatory pathways may be of value for enhancing innate immunity in feedlot cattle at times of susceptibility to disease.  相似文献   
25.
The purpose of this investigation was to report on the total phenolics, anthocyanins, and oxygen radical absorbance capacity (ORAC) of strawberry, peach, and apple, the influence of dehydration and ascorbic acid treatments on the levels of these compounds, and the effect of these treatments on fruit color. Results showed that fresh strawberry had the highest levels for total phenolics [5317.9 mg of chlorogenic acid equivalents (CAE)/kg], whereas lower levels were found in fresh apple and peach (3392.1 and 1973.1 mg of CAE/kg, respectively), and for anthocyanins (138.8 mg/kg), whereas lower levels were found in fresh apple and peaches (11.0 and 18.9 mg/kg, respectively; fresh strawberry had an ORAC value of 62.9 mM/kg Trolox equivalents. The fresh apple and peach were found to have ORAC values of 14.7 and 11.4 mM/kg of Trolox equivalents, respectively. The color values indicated that the addition of 0.1% ascorbic acid increased the lightness (L) and decreased the redness (a) and yellowness (b) color values of fresh strawberry, peach, and apple, sliced samples, and the puree made from them. Also, results showed that dehydration is a good method to keep the concentrations of total phenolics and anthocyanins and ORAC values at high levels.  相似文献   
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Christ's thorn (Paliurus spina-christi Mill.) tree is an important and valuable forestry species and has significant potential in afforestation and reforestation systems. In recent years, dieback symptoms were observed on Paliurus spina-christi trees in Gilan-e Gharb region of Kermanshah province, west Iran. During 2020 to 2021, Christ's thorn trees that exhibit branch dieback symptoms were sampled for fungal isolations. The pathogenicity tests, biochemical assay of growth, acid production on creatine sucrose agar (CREA) medium and morphological and molecular investigations (ITS and β-tubulin regions) identified Paecilomyces formosus as a dieback causal agent. This is the first report of P. formosus pathogenicity on Paliurus spina-christi trees. Furthermore, disease severity was assayed on 11 tree species under three different temperatures 15, 25 and 35°C. Disease severity caused by all isolates on detached branches was greater at 35°C than at 15 and 25°C. This study presents the host range of this pathogen and showed that these potential hosts are prone to this pathogen under high temperatures, which forest trees experienced in recent decades.  相似文献   
29.
Journal of Plant Diseases and Protection - Methylated soy and chickpea proteins (MSP and MCP, respectively), and 11S globulin (a soy protein fraction), are characterized by net positive charges and...  相似文献   
30.
Theileria annulata is endemic in northern Sudan, hindering all efforts at upgrading cattle for milk production. T. lestoquardi clinical cases occur throughout the year and causes annual outbreaks that result in substantial losses in sheep. In the northern Sudan both cattle and small ruminants are frequently raised together and/or share common grazing grounds at river banks. In an attempt to evaluate field cross infectivity of Theileria lestoquardi and T. annulata in cattle and sheep respectively, a PCR analysis was carried out on samples collected from closely reared sheep and cattle using both T. annulata and T. lestoquardi specific primers. A total of 19 sheep out of 51 (37.3%) were positive for T. lestoquardi while four sheep (7.8%) showed T. annulata specific amplicons. A total of 38 out of 52 (73.1%) surveyed cattle were PCR positive for T. annulata and only two (3.8%) showed T. lestoquardi specific bands. These findings indicate complex epidemiology of both infections in areas where both parasites are transmitted by the same vector and call for further investigations of this phenomenon.  相似文献   
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