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AIM: To determine the effect of increasing molybdenum (Mo) intakes on serum and liver copper (Cu) concentrations and growth rates of grazing red deer (Cervus elaphus).

METHODS: Molybdenum- and Cu-amended fertilisers were applied to six 1.1-ha paddocks in a 3 × 2 design. Three levels of Mo were applied on two paddocks at each level in mid April (designated Day 1); levels were: none (control), 0.5 (medium) and 1.0 (high) kg Mo/ha as sodium molybdate. In late May (Day 39), two levels of Cu (none and 3.0 kg Cu/ha, as copper sulphate) were applied to each of the three levels of Mo-treated paddocks. Pasture Mo, Cu and sulphur (S) concentrations were measured at about fortnightly intervals. In late June (Day 74), ten 6-month-old red deer hinds were placed on the six experimental pastures, and serum and liver Cu concentrations were monitored at about monthly intervals for 102 days. The hinds were weighed on four occasions during the trial.

RESULTS: Mean pasture Mo concentrations on Day 56 were 2, 4.6 and 11.3 mg/kg dry matter (DM) for the untreated control, medium and high Mo-treated pastures, respectively. Pasture Cu concentration was 95 mg/kg DM on Day 59, 53 mg/kg DM on Day 90, and 9 mg/kg DM by Day 153. Mean S concentration in pasture was 3.3 (range 3.03–3.45) g/kg DM. Copper application to pasture had no significant effect on serum and liver Cu concentrations in deer so data were pooled within Mo treatment. Mean initial (Day 74) serum Cu concentration was 9.2 µmol/L. In the deer grazing the control Mo pasture, this increased to 10.3 µmol/L on Day 112, before decreasing to 6.4 µmol/L on Day 176. In deer grazing the medium and high Mo-treated pastures, mean serum Cu concentrations were 3.8 and 3.9 µmol/L, respectively, on Day 112, and 2.5 and 3.3 µmol/L, respectively, on Day 176. Mean initial (Day 74) liver Cu concentration was 131 µmol/kg fresh tissue. In the deer grazing the control Mo pasture, this declined to 120 and 52 µmol/kg on Days 112 and Day 176, respectively. In deer grazing the medium and high Motreated pastures, liver Cu concentrations decreased to 55 and 52 µmol/kg fresh tissue, respectively, on Day 112, and 21 and 20 µmol/kg fresh tissue, respectively, on Day 176. Mean serum and liver Cu concentrations were not significantly different between deer grazing the medium and high Mo-treated pastures, and were lower (serum p=0.003, liver p<0.001) in those groups than in deer grazing the untreated control pastures. No clinical signs of Cu deficiency associated with lameness were observed. Deer grazing pastures that had Mo concentrations >10 mg/kg DM had lower (p=0.002) growth rates (100 vs 130 g/day) than those on pastures containing <2.4 mg Mo/kg DM.

CONCLUSION: Increasing pasture Mo concentrations from 2 mg/kg DM to ≥4.6 mg/kg DM significantly reduced serum and liver Cu concentrations in grazing deer. Reduced growth rate was observed at pasture Mo concentrations >10 mg/kg DM.  相似文献   
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During the last decades, physiological effects of oestrogens have been increasingly explored by scientists and biotechnologists. Estrogens exert a wide range of effects on a large variety of cell types. Oestrogen and its receptors are essential for sexual development and reproduction. Estrogen receptor alpha is a nuclear receptor activated by the hormone oestrogen. In male, ERα is encoded by the gene estrogen receptor gene 1 (ESR1), responsible for better fertility. The ESR1 is involved in the reabsorption of luminal fluid during the transit of spermatozoa from the testis to the head of the epididymis which is important for their survival and maturation during epididymal storage. The absence of ESR1 leads to reduced epididymal sperm content, reduced sperm motility and fertilizing ability. Therefore, this is a good startby to study the expression pattern of estrogen receptor 1 gene in high‐fertile (G1) and low‐fertile (G2) bucks of Jamunapari and Barbari breeds identified on the basis of seminal quality traits and fertility trials. RNA was extracted from the tissues by TRIzol method. The identification and expression pattern of caprine ESR1 gene was analysed by real‐time PCR (Roche LC‐480). Our work shows that the relative quantification by RT‐PCR indicates more fold in head of epididymis as compared to spleen of caprine ESR1 gene. Furthermore, the RT‐PCR indicated that fertile bucks of Jamunapari breed have more fold value as compared to Barbari breed in respect of reproductive organ.  相似文献   
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Singh  R. K.  Chaudhary  R. S.  Somasundaram  J.  Sinha  N. K.  Mohanty  M.  Hati  K. M.  Rashmi  I.  Patra  A. K.  Chaudhari  S. K.  Lal  Rattan 《Journal of Soils and Sediments》2020,20(2):609-620
Purpose

Accelerated erosion removes fertile top soil along with nutrients through runoff and sediments, eventually affecting crop productivity and land degradation. However, scanty information is available on soil and nutrient losses under different crop covers in a vertisol of Central India. Thus, a field experiment was conducted for 4 years (2010–2013) to study the effect of different crop cover combinations on soil and nutrient losses through runoff in a vertisol.

Materials and methods

Very limited information is available on runoff, soil, and nutrient losses under different vegetative covers in a rainfed vertisol. Thus, the hypothesis of the study was to evaluate if different crop cover combinations would have greater impact on reducing soil and nutrient losses compared to control plots in a vertisol.

This experiment consisted of seven treatment combinations of crop covers namely soybean (Glycine max) (CC1), maize (Zea mays) (CC2), pigeon pea (Cajanus cajan) (CC3), soybean (Glycine max)?+?maize (Zea mays) ??1:1 (CC4), soybean (Glycine ma x))?+?pigeon pea (Cajanus cajan) ?2:1 (CC5), maize (Zea mays)?+?pigeon pea (Cajanus cajan) ??1:1 (CC6), and cultivated fallow (CC7). The plot size was 10?×?5 m with 1% slope, and runoff and soil loss were measured using multi-slot devisor. All treatments were arranged in a randomized block design with three replications.

Results and discussion

Results demonstrated that the runoff and soil loss were significantly (p?<?0.05) higher (289 mm and 3.92 Mg ha?1) under cultivated fallow than those in cropped plots. Among various crop covers, sole pigeon pea (CC3) recorded significantly higher runoff and soil loss (257 mm and 3.16 Mg ha?1) followed by that under sole maize (CC2) (235 mm and 2.85 Mg ha?1) and the intercrops were in the order of maize?+?pigeon pea (211 mm and 2.47 Mg ha?1) followed by soybean?+?maize (202 mm and 2.38 Mg ha?1), and soybean?+?pigeon pea (195 mm and 2.15 Mg ha?1). The lowest runoff and soil loss were recorded under soybean sole crop (194 mm and 2.27 Mg ha?1). The data on nutrient losses indicated that the highest losses of soil organic carbon (SOC) (25.83 kg ha?1), total nitrogen (N), phosphorus (P), and potassium (K) (7.76, 0.96, 32.5 kg ha?1) were recorded in cultivated fallow (CC7) as compared to those from sole and intercrop treatments. However, sole soybean and its intercrops recorded the minimum losses of SOC and total N, P, and K, whereas the maximum losses of nutrients were recorded under pigeon pea (CC3). The system productivity in terms of soybean grain equivalent yield (SGEY) was higher (p?<?0.05) from maize?+?pigeon pea (3358 kg ha?1) followed by that for soybean?+?pigeon pea (2191 kg ha?1) as compared to sole soybean. Therefore, maize?+?pigeon pea (1:1) intercropping is the promising option in reducing runoff, soil-nutrient losses, and enhancing crop productivity in the hot sub-humid eco-region.

Conclusions

Study results highlight the need for maintenance of suitable vegetative cover as of great significance to diffusing the erosive energy of heavy rains and also safe guarding the soil resource from degradation by water erosion in vertisols.

  相似文献   
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Amlan K. Patra   《Livestock Science》2009,121(2-3):239-249
A meta-analysis of data obtained from previous studies was conducted to understand the responses of foliage supplementation on intakes of basal DM (BDMI) and total DM (TDMI), and daily gain (ADG). Thirty-four published studies containing 223 treatments and 1127 sheep met criteria for inclusion in the meta-analysis. Major predictive variables considered were percentages of foliages in diet (SD), CP in foliages (PS), NDF in foliages (FS), NDF in forages (FB), CP in basal roughages (PB), CP in diet (PD) and foliage CP intake (SPI). TDMI (g/d) increased quadratically (P < 0.001) with increasing PS, FS, SPI (R2 = 0.66), PB, SD (R= 0.58) and PD (R2 = 0.73). The maximal response of TDMI were 778 g/d at 42% of SD, 894 g/d at 19.8% PD, 893 g/d at 148 g/d SPI and 749 g/d at 26.4% PS (P < 0.001; R2 = 0.58, 0.73, 0.66, and 0.37, respectively). BDMI increased quadratically with increasing SD, PD and PB, but decreased quadratically (P < 0.001) with increasing PS (P < 0.001; R2 = 0.07). The breakpoint of BDMI was 570 g/d at 6.58% of PD in the diet (P < 0.001, R2 = 0.28). Overall, BDMI responded at very low level of SD in the diet, peaking at 7.6% SD with BDMI of 572 g/d (P < 0.001, R2 = 0.72). However, when PB was less than 3%, the maximal BDMI was 489 g/d at foliage levels of 25.7%. When PB was between 3 and 6%, maximal BDMI was at 13% of foliage in the diet and the basal forage intake of 597 g/d; whereas, BDMI decreased linearly with SD when PB was greater than 6%. BDMI (g/d) decreased quadratically when foliage CP percentages were lesser than 10%, but increased quadratically with PS when foliage CP percentages were greater than 10%. ADG responded positively and quadratically to PS, SPI, SD, PD and TDMI (g/d) and the relationships were moderate to high. However, ADG (g/d) decreased linearly with increasing FS (P < 0.001, R2 = 0.35). The maximal ADG was 42 g/d at 43% of SD, 41 g/d at 9.4% PD, 42 g/d at 53 g/d SPI, 35 g/d at 25% PS and 46 g/d at TDMI of 889 g/d (P < 0.001; R2 = 0.74, 0.84, 0.74, 0.29 and 0.74, respectively). It is concluded that the interactions of quality and quantity of foliage supplements and quality of basal forages affect intakes of basal and total DM, and growth in sheep.  相似文献   
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The increasing drug resistance of infectious microorganisms is considered a primary concern of global health care. The screening and identification of natural compounds with antibacterial properties have gained immense popularity in recent times. It has previously been shown that several bioactive compounds derived from marine algae exhibit antibacterial activity. Similarly, polyphenolic compounds are generally known to possess promising antibacterial capacity, among other capacities. Phlorotannins (PTs), an important group of algae-derived polyphenolic compounds, have been considered potent antibacterial agents both as single drug entities and in combination with commercially available antibacterial drugs. In this context, this article reviews the antibacterial properties of polyphenols in brown algae, with particular reference to PTs. Cell death through various molecular modes of action and the specific inhibition of biofilm formation by PTs were the key discussion of this review. The synergy between drugs was also discussed in light of the potential use of PTs as adjuvants in the pharmacological antibacterial treatment.  相似文献   
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Teleost fish lack the enzyme for endogenous synthesis of ascorbic acid (AA), an essential micronutrient for fish. The aim of this study was to examine the effect of higher levels of dietary vitamin C on growth, nutritional quality, and immunomodulation in the Indian major carp, rohu (Labeo rohita). Four groups of L. rohita were fed experimental diets containing either no vitamin C (control) or supplemented with vitamin C at 500 mg kg−1 (Exp-1), 1000 mg kg−1 (Exp-2), or 1500 mg kg−1 (Exp-3) for 60 days. Growth parameters (NWG, ADG, and SGR), serological parameters (TSP, TSA, TSG, and A:G), haematological parameters (TLC, TEC, Hct, MCV, and MCH), and different non-specific immunological parameters (PR, PI, respiratory burst activity, and bactericidal activity) were evaluated during the experimental trial. Fish fed a vitamin C-supplemented diet showed higher specific growth rate (SGR) up to 1000 mg kg−1 compared with control fish. Different haematological and serological parameters along with non-specific immune parameters were influenced by vitamin C supplementation. Among the non-specific immune parameters phagocytic activity (PR and PI) and respiratory burst activity (NBT cells) were significantly (P ≤ 0.05) enhanced by increasing doses of vitamin C supplementation. Higher levels of dietary vitamin C significantly (P ≤ 0.05) enhanced protection against Aeromonas hydrophila (AH1) infection compared with controls. Results from this study help to establish the beneficial effect of vitamin C on growth and immunmodulation in rohu (L. rohita).  相似文献   
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