Effect of Relaxin on Fertility Parameters of Frozen–Thawed Buffalo (Bubalus bubalis) Sperm

The aim of this work was to evaluate the effect of relaxin on fertility parameters of buffalo frozen/thawed sperm. Sperm were incubated in the absence of capacitating agents (negative control), with a known capacitating agent such as heparin (positive control) and with 50 and 100 ng/ml relaxin for 2 and 4 h. Sperm viability, motility, capacitation and the effect of relaxin on the fertilizing ability after heterologous IVF were evaluated. Although viability was not affected, relaxin increased (p < 0.05) sperm motility compared to the negative and positive controls both after 2 h (60.0 ± 2.0, 60.0 ± 3.1, 68.3 ± 1.7 and 69.4 ± 2.7, respectively, in negative control, positive control, 50 and 100 ng/ml relaxin) and 4 h (55.0 ± 2.5, 53.3 ± 3.0, 62.2 ± 3.0 and 65.0 ± 3.2, respectively, in negative control, positive control, 50 and 100 ng/ml relaxin) incubation. When sperm were incubated with both 100 ng/ml relaxin and heparin, a decrease (p < 0.01) of pattern A, that is low capacitation level, was observed compared to the negative control both after 2 h (54.4, 34.3 and 36.4%, respectively, in negative control, positive control and 100 ng/ml relaxin) and 4 h (51.9, 35.0 and 34.3%, respectively, in negative control, positive control and 100 ng/ml relaxin). Moreover, an increase (p < 0.01) of pattern EA, that is high capacitation level, was recorded with 100 ng/ml relaxin and heparin compared to the negative control both after 2 h (44.1, 59.3 and 57.7%, respectively, in negative control, positive control and 100 ng/ml relaxin) and after 4 h (43.0, 54.4 and 56.0%, respectively, in negative control, positive control and 100 ng/ml relaxin). Finally, relaxin increased (p < 0.01) cleavage rate compared to the negative control (57.1 ± 4.4, 72.5 ± 6.0, 71.4 ± 5.5 and 73.6 ± 2.9, respectively, in negative control, positive control, 50 and 100 ng/ml relaxin). In conclusion, relaxin has a beneficial effect on motility, capacitation and fertilizing ability of frozen–thawed buffalo sperm.     

Blood oxygen transport and hemoglobin function in three tropical fish species from northern Australian freshwater billabongs

The oxygen binding properties of whole blood and hemoglobin were studied in three phylogenetically distant tropical teleosts inhabiting freshwater billabongs that exhibit marked seasonal oxygen stratification. The water breathing saratoga (Scleropages jardinii, Family Osteoglossidae), derived from an ancient divergence of the stem line leading to all other extant teleosts, has a low blood oxygen carrying capacity, Bohr and Root effect, and a high blood oxygen affinity. Erythrocytes contain a single major hemoglobin component, and equimolar concentrations of ATP and GTP. The tarpon (Megalops cyprinoides, Family Megalopidae), a facultative air-breather, has the highest blood oxygen carrying capacity and Bohr effect, and a low blood oxygen affinity and Root effect. Erythrocytes contain a single major hemoglobin and ATP as a putative regulator of hemoglobin oxygen affinity. Barramundi (Lates calcarifer, Family Centropomidae), is an obligate water-breather with intermediate blood oxygen binding properties, and the smallest Root effect. Erythrocytes contain at least 7 hemoglobins, and equimolar concentrations of ATP and GTP. Functional properties of these three blood oxygen transport systems are considered in terms of the respiratory environment and demand for oxygen. Our interpretation supports the hypothesis that the process of speciation can lead to divergence in physiological mechanisms, irrespective of past or present selection pressures.     

Amino acid profile of the quinoa (Chenopodium quinoa Willd.) using near infrared spectroscopy and chemometric techniques

The high content of amino acids of the quinoa, especially essential amino acids (higher than other cereals) makes a food increasingly demanded by consumers. A total of twelve amino acids (arginine, cystine, isoleucine, leucine, lysine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine and valine) were analyzed in quinoa samples from Chile by near infrared spectroscopy (NIR) with direct application to the samples of a remote fiber-optic reflectance probe. The calibration results using modified partial least squares (MPLS) regression satisfactorily allowed the determination of the concentrations of this amino acid group with high multiple correlation coefficients (RSQ = 0.97–0.71) and low standard prediction errors (SEPC = 0.07–0.20). The prediction capacity (RPD) for the arginine, the cystine, the isoleucine, the lysine, the serine, the threonine, the tryptophan, the tyrosine and the valine ranged between 2.6 and 5.2, for the rest of amino acids were higher to 1.8, indicating that the NIRS equations obtained were applicable to unknown samples. It has confirmed that NIRS technology is a method that may be useful to replace the traditional methods for routine analysis of some amino acids.     

Monensin controlled-release intraruminal capsule for control of bloat in pastured dairy cows

Monensin, a polyether ionophore antibiotic, is potentially an important agent for bloat relief in dairy cows grazing temperate legume-based pasture. A series of studies was undertaken to determine the effect of monensin, when delivered continuously in the rumen of lactating dairy cows by means of controlled-release capsules (monensin CRC). Such devices release approximately 300 mg/head/day for 100 d. A short-term pilot study made at Ruakura, New Zealand, tested monensin CRC in cows selected for high susceptibility to bloat and grazing lucerne (Medicago sativa) or red clover (Trifolium pratense). Treatment significantly reduced the incidence of bloat, while milk yield and protein yield were increased. There was no effect on fat yield. Following the pilot study, 6 large-scale field experiments involving a total of 368 lactating dairy cows, were made in Australia and New Zealand to confirm the effectiveness of monensin CRC for bloat control and to measure the effect of such treatment on milk production and composition. A severe bloat problem occurred in 2 experiments, mild bloat occurred in 2 others, while no visual signs of bloat were observed in the remaining 2 experiments. Bloat was significantly (P less than 0.05) reduced by monensin CRC treatment when data was pooled over the 4 experiments in which bloat occurred. Daily milk yield was increased in all experiments from a mean of 17.7 in untreated groups to 18.8 kg/head/day (P less than 0.05) in monensin CRC-treated cows. Protein percentage was not affected by treatment, while there was a decrease from 4.29 to 4.10% fat, although total fat yield was not affected.(ABSTRACT TRUNCATED AT 250 WORDS)     

柴达木盆地弃耕地盐渍状况的主分量分析

采用主分量分析（PCA）方法对柴达木盆地弃耕地盐渍化状况进行了研究，结果表明，该地属于中重度氯化物盐渍地、耕作层含盐量在0．5％－4．0％之间，盐分表聚强烈，基本无自然淋溶过程。耕作层第一、二主分量显著，累计贡献率高达95．0％左右，反映了该区土壤含盐量及盐离子分布规律，认为全盐量、Cl^-,Mg^2＋是该弃耕地盐渍环境的特征因子。     

Protection of lambs against enteric colibacillosis by vaccination of ewes

Pregnant ewes were vaccinated twice, seven weeks and three weeks before lambing, with a multivalent formalin-killed Escherichia coli vaccine containing an added K99, F41 antigen preparation. Lambs born to vaccinated and unvaccinated ewes were exposed to oral infection with E coli B44 (09:K30, K99, F41). All 10 lambs from vaccinated ewes were protected whereas all 10 control lambs developed severe diarrhoea and five died or were killed in extremis. In the following year, previously immunised ewes were given a single dose of the vaccine two weeks before lambing. Eleven of their 12 lambs were protected against a similar challenge, which caused the death of six of eight control lambs and severe diarrhoea in the two survivors. Higher levels of antibody to the K99, F41 preparation were detected by enzyme-linked immunosorbent assay in the serum and colostrum from vaccinated ewes and in the serum of their lambs when compared with similar samples from control ewes and lambs.