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121.
Twenty nursing Awassi ewes (BW = 50 ± 2.35 kg, age = 4.5 ± 1.2 years) with their lambs were used to evaluate the effects of feeding calcium salts in lactation diets on performance and pre-weaning growth of their lambs. Treatments were 0% calcium salts (CON) or 5% calcium salts (FAT). At the end of the study, a digestibility experiment was performed. Milk yield was greater (P < 0.05) for ewes fed the FAT diet than the CON diet. Milk composition was similar (P > 0.05) between diets. However, milk energy value (kcal/day) tended to be greater (P = 0.07) for the FAT diet than the CON diet. Concentrations of milk C18:1c9 and C20:0 were greater (P < 0.05) in ewes fed the FAT diet than the CON diet. However, concentration of trans-10, cis-12 CLA was lower (P = 0.05) in the FAT diet than in the CON diet. No differences in feed intake and body weight change were detected between diets. Digestibility of dry matter, organic matter, crude protein, ether extract, neutral detergent fiber, and acid detergent fiber were similar (P > 0.05) for diets. For lambs, weaning weight was not affected by treatments. However, average daily gain and total gain were greater (P = 0.053) for the FAT diet than the CON diet. Results suggest that supplementing lactating ewes with calcium salts at the beginning of lactation phase improves daily milk yield of ewes and pre-weaning growth of their lambs with no major negative impact on feed intake and digestibility.  相似文献   
122.
  1. The Kemp’s ridley (Lepidochelys kempii) is the world’s most endangered sea turtle species. Predominately nesting at only one beach in Mexico, this species declined to an estimated 300 females in the mid-1980s. Conservation efforts in the United States and Mexico, including a head start programme in southern Texas in which hatchlings were reared in captivity for several months before being released into the wild, resulted in the recovery of this species.
  2. Although genetic data have previously been used to assess the success of the head start programme and dispersal of individual adults, data on immature turtles sampled at foraging areas and adult females sampled at the main nesting beach in Mexico are lacking. Genetic characterization of immature individuals is important for understanding recruitment, survival, and population demography, while genetic data on individuals from Mexico are essential for understanding dispersal and overall genetic diversity in this species.
  3. To address these gaps, mitochondrial DNA data were collected from 106 immature individuals sampled at four different foraging sites in the northern Gulf of Mexico and from 18 nesting females at the primary nesting beach in Mexico.
  4. Two previously unknown mitochondrial DNA haplotypes were discovered among the immature individuals.
  5. Except for these two new haplotypes, the genetic diversity of immature individuals in the northern Gulf of Mexico closely corresponds to that of adults sampled in Mexico, which suggests that much of the diversity within the nesting population can be found among immature animals dispersing to foraging grounds, including locations in the northern Gulf of Mexico.
  6. Continued monitoring of the genetic variation of different life stages of this species across its distribution range will help assess the success of conservation programmes by ensuring the maintenance of genetic diversity and representation of this diversity across the species’ distribution range.
  相似文献   
123.
An increasing number of synthetic pyrethroids are used as an environmental friendly substitute of organophosphate and organochlorine insecticides. Pesticide pollution in the coastal ecosystem of Korea is considered to be a cause of slow growth and prevalence of diseases in commercial fishes. Therefore, it is necessary to develop fast techniques to detect insecticide toxicities. In the present work the results of rapid and inexpensive laboratory experiments show the patho‐physiological alteration of blood parameters to sublethal concentration of pyrethroid insecticide (cypermethrin) in the commercially important Korean rockfish (Sebastes schlegeli). Cypermethrin‐exposed fish showed erythropenia, low haematocrit and haemoglobin content and hyperglycemia, especially for long‐term exposure at high concentrations. Cypermethrin caused increased levels of serum glutamic‐acid‐oxylacetic‐acid‐transaminase, glutamic‐acid‐pyruvic‐acid‐transaminase and alkaline phosphatase, concomitant with a decreased concentration of chloride ion and blood serum osmolality, indicating the disruptive activity of cypermethrin after 8 weeks exposure. Moreover, reduced level of serum total protein, albumin, cholesterol, lysozyme activity and significantly higher level of glucose, bilirubin and malondialdehyde were measured and attributed to an increased demand for energy by fish under stress to cope with detrimental conditions imposed by chronic exposure to the toxicant.  相似文献   
124.
Lack of data especially pertaining to the chemistry of mangrove wood species makes it difficult to prepare successful plans for their conservation and to use mangroves as a source of wood fiber. In this paper, chemical characterizations of the six main mangrove species of Bangladesh [namely Keora (Sonneratia apetala), Geoa (Excoecaria agallocha), Bine (Avicennia alba), Sundari (Heritiera fomes) Pashur (Xyloccarpous mekongests), and Kakra (Bruguiera gymnorhiza)] were investigated. The chemical results revealed that these species contain high percentages of dichloromethane followed by methanol extractives. Methanol extracts in Pashur, Sundari, and Bine were higher than 10%, which indicates high percentage of tannin material. The total lignin content in these species was higher than 25%, except for Gewa (23.6%) and Pashur (21.3%), which is higher than that of the normal range of hardwood. The pentosan content in these six species was within the range of 19.4–22.8%. The α-cellulose content in Keora and Gewa was acceptable for pulp production, but the others were lower than the normal range of hardwood. Alkaline nitrobenzene oxidation showed that all these species had a very high syringaldehyde to vanillin (2.6–5.0) ratio except Keora (1.6). Surprisingly, rhamnose is the main constituent with xylose of hemicelluloses of these six mangrove species. The ash content in these six mangrove wood species was also higher than that in normal hardwood.  相似文献   
125.
Values (%) for true digestibility of crude protein and individual amino acids in 20 selected foods were determined by the rat balance (fecal) method. The products were fed as the sole source of protein in diets containing 8% crude protein (N × 6.25). Lowest true protein digestibility values (79–84) were obtained for pinto beans, kidney beans and lentils; intermediate values (89–92) were obtained for chick peas, beef stew, skim milk (over heated), rolled oats, whole wheat cereal, and pea protein concentrate; and highest values (94–100) were obtained for sausage, macaroni-cheese, rice-wheat gluten cereal, skim milk, tuna, soy isolate, peanut butter, chicken frankfurters, beef salami, casein and casein + methionine. In animal foods, peanut butter and soy isolate, the differences between true digestibility of crude protein and most individual amino acids were less than 5%. However, the values for true digestibility of methionine and cystine were up to 44% lower than those of crude protein in pinto beans, kidney beans, lentils, chick peas and pea concentrate. In these legumes, digestibility of crude protein was not a good predictor of digestibility of the limiting amino acids.  相似文献   
126.
The methanol extract of Leucas aspera flowers, its fractions, the alkaloidal residue and the expressed flower juice, tested for antimicrobial activity, showed good antibacterial activity for methanol extract and methanol fraction with maximum activity for the alkaloidal residue.  相似文献   
127.
Wheat production in Morocco is constrained by both scarce climate and degraded soil quality. There is an urgent need to revert production decline while restoring country’s soils. Among conservation tillage systems known for their improvement in yield, no-till technology was found to influence soil quality as well. Soil quality indices are also affected by wheat rotations at medium and long-terms. This paper discusses changes in selected properties of a Calcixeroll soil, including total and particulate soil organic matter (SOM), pH, total N and aggregation, subjected, for 11 consecutive years, to various conservation and conventional agricultural systems. Tillage systems included no-tillage (NT) and conventional tillage (CT). Crop rotations were continuous wheat, fallow–wheat, fallow–wheat–corn, fallow–wheat–forage and fallow–wheat–lentils. Higher aggregation, carbon sequestration, pH decline and particulate organic matter (POM) buildup are major changes associated with shift from conventional- to NT system. Better stability of aggregates was demonstrated by a significantly greater mean weight diameter under NT (3.8 mm) than CT system (3.2 mm) at the soil surface. There was 13.6% SOC increase in (0–200 mm) over the 11-year period under NT, while CT did not affect much this soil quality indicator. Another valuable funding is the stratification of SOC and total nitrogen in NT surface horizon (0–25 mm) without their depletion at deeper horizon compared to tillage treatments. Fallow–wheat system resulted in reduction of SOC compared to WW, but 3-year wheat rotation tended to improve overall soil quality. Benefits from crop rotation in terms of organic carbon varied between 2.6 and 11.7%, with fallow–wheat–forage exhibiting the maximum. Combined use of NT and 3-year fallow rotation helped to improve soil quality in this experiment.  相似文献   
128.
Cooling of equine semen obtained from some stallions results in lower seminal quality and viability when the seminal plasma (SP) is present. The objective of this study was to evaluate the effect of the removal of SP using a Sperm Filter on the viability of cooled stallion semen. For this purpose, 31 stallions were used. Their ejaculates were divided into three groups: CN, semen was diluted with an extender; FLT, SP was removed by filtration; and CT, SP was removed by centrifugation and cooled to 15°C for 24 hours. Sperm kinetics and plasma membrane integrity were evaluated immediately after collection (T0) and after 24 hours of refrigeration (T1). No difference (P > .05) was noted at T1 for total sperm motility (TM), progressive sperm motility, or plasma membrane integrity when semen samples from all the stallions were analyzed. However, when samples from stallions termed “bad coolers” were analyzed (TM = <30% at T1), a difference was observed in TM and progressive sperm motility for CN compared with FLT and CT at T1. Sperm recovery was greater when SP was removed using the filter (FLT) to that when the SP was removed by centrifugation (CN) (89% vs. 81%). Thus, we concluded that filtering with a Sperm Filter is an efficient and practical method for removal of SP from stallion ejaculates, with lower sperm loss than centrifugation. We also found that the presence of SP reduces the quality and viability of cooled semen from stallions whose semen is sensitive to the process of refrigeration.  相似文献   
129.
A halotolerant, gram positive, motile and rod, was isolated from the E1 Gol6a lake of Ghardaia, Alegria and screened for its antimicrobial potential. The strain showed an inhibitory effect to gram positive and gram negative bacteria against Cladosporium spp. and a slight inhibitory effect against C. albicans using chloroform as the extraction solvent and the nutrient broth as production medium. 16S rRNA sequencing showed that the isolate named LMB3981 is a new taxon in the family of Bacillaceae (with 96% similarity). The strain is close to Filobacillus milosensis and Bacillus haloalkaliphilum with 95% similarity. The phenotypic study showed differences between LMB3981 and two strains that are near and have confirmed the results of 16S rRNA sequencing by specific metabolic properties of the strain.  相似文献   
130.
The response of broiler chickens to two levels of endo‐1,4‐β xylanase (EC 3.2.1.8) and endo‐1,3‐β glucanase (EC 3.2.1.6) combination (with and without), three levels of digestible lysine (0.8%, 0.9% and 1.0% with the applicability of ideal protein concept) and two levels of cottonseed meal (CSM; 20% and 30%) were evaluated in 2 × 3 × 2 factorial arrangement. A total of 2448 male Hubbard broiler chicks were fed on practical vegetable‐based mash diets having 2750 kcal metabolizable energy (ME) per kg and 18.5% crude protein (CP) from the age of day 1 to 42. The supplemental enzyme had minimum 1100 units of endo‐1,4‐β xylanase and 100 units of endo‐1,3‐β glucanase/kg of finished diet. The addition of CSM at 30% resulted in increasing arginine to lysine ratio. A decrease in dressing and breast percentages were observed by the addition of 30% CSM. The digestible lysine at 1.0% decreased the body weight (BW) gain and lowered the mortality during day 1 to 21 whereas the BW gain and feed:gain ratio were unaffected among the three digestible lysine levels during day 1 to 42. The antibody titres against Newcastle and infectious bursal disease viruses were improved with the increasing levels of digestible lysine. The enzyme supplementation improved the apparent ME and digestibility coefficient of nitrogen when it was used with 30% CSM. No effect of enzyme, lysine, CSM or their interactions was observed on serum iron, gizzard and liver weights or abdominal fat percentage. The results showed that increasing digestible lysine improved the antibody titre but did not improve the growth performance and carcass characteristics; supplemental enzyme failed to show any improvement in performance of birds fed on CSM‐based diets.  相似文献   
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