Use of biochemical and protein profiles of seminal plasma to prediction of semen quality and fertility in stallions

The identification of various substances in seminal plasma has opened the way to study their functionality. It was aimed to identify the electrophoretic protein profile (EPP) and biochemical parameters (BP) of seminal plasma (SP) as predictors of semen quality and fertility in stallion. Forty-six ejaculates from 7 fertile stallions, aged between 6-26 years, were collected from May to July and 117 mares were used to obtain fertility data. For each ejaculate, volume, sperm motility, concentration were determined and seminal plasma samples were collected to perform one- -dimensional electrophoresis and biochemical profiling. Following the estrus detection, mares were inseminated with fresh sperm. Pregnancy rates and foal rates were recorded. The concentration of 15-18 kDa molecular weight (MW) proteins has shown a positive correlation with sperm concentration and foal rate. Besides, a strong positive correlation was found between sperm concentration and 23-28 kDa MW proteins (r=0.77). The volume of 19-22 kDa MW proteins was negatively correlated with pregnancy and foal rate. Similarly, the volume of high MW proteins (173-385 kDa) correlated negatively with sperm motility and foal rate. Apart from the protein profile, while Magnesium and Glucose levels were negatively correlated with sperm quality and foal rate, Cholesterol level was a positive indicator of the quality of semen as well as the foaling rate. Moreover, the total protein level was correlated negatively with the sperm concentration whereas triglyceride was correlated positively. In conclusion, EPP and BP of seminal plasma are valuable clinical tools as predictors of fertility and semen quality in the stallion.

Brain lateralization probed by water diffusion at the atomic to micrometric scale

Combined neutron scattering and diffusion nuclear magnetic resonance experiments have been used to reveal significant interregional asymmetries (lateralization) in bovine brain hemispheres in terms of myelin arrangement and water dynamics at micron to atomic scales. Thicker myelin sheaths were found in the left hemisphere using neutron diffraction. 4.7 T dMRI and quasi-elastic neutron experiments highlighted significant differences in the properties of water dynamics in the two hemispheres. The results were interpreted in terms of hemisphere-dependent cellular composition (number of neurons, cell distribution, etc.) as well as specificity of neurological functions (such as preferential networking).

Anomalous water dynamics in brain: a combined diffusion magnetic resonance imaging and neutron scattering investigation

Water diffusion is an optimal tool for investigating the architecture of brain tissue on which modern medical diagnostic imaging techniques rely. However, intrinsic tissue heterogeneity causes systematic deviations from pure free-water diffusion behaviour. To date, numerous theoretical and empirical approaches have been proposed to explain the non-Gaussian profile of this process. The aim of this work is to shed light on the physics piloting water diffusion in brain tissue at the micrometre-to-atomic scale. Combined diffusion magnetic resonance imaging and first pioneering neutron scattering experiments on bovine brain tissue have been performed in order to probe diffusion distances up to macromolecular separation. The coexistence of free-like and confined water populations in brain tissue extracted from a bovine right hemisphere has been revealed at the micrometre and atomic scale. The results are relevant for improving the modelling of the physics driving intra- and extracellular water diffusion in brain, with evident benefit for the diffusion magnetic resonance imaging technique, nowadays widely used to diagnose, at the micrometre scale, brain diseases such as ischemia and tumours.

The effects of different PMSG doses on estrus behavior and pregnancy rate in Angora goats

Artificial insemination protocols depend on efficient behavioral estrus detection and insemination time in Angora goat. Therefore, we aim to determine the accuracy of an estrus scoring system in Angora goats with different PMSG doses during the breeding season. Does (n: 260) were randomly divided into three groups: group-1 (n: 93), group-2 (n: 85) and group-3 (n: 82). All animals received an intravaginal sponge on day 0 for 11 days, and on the day of sponge insertion 150 μg prostaglandin F2Α was administered. Pregnant mare's serum gonadotropin was injected 300, 400 and 500 IU intramuscularly 24 h before sponge removal to groups 1, 2 and 3, respectively. Estrus signs were detected with a teaser buck, 24 h after sponge removal according to a visual scoring system. Artificial insemination was performed with 0.25 ml fresh diluted semen at 43 to 45 h after sponge removal. Differences were observed within PMSG groups in terms of standing, tail wagging, courtship behavior, vaginal discharge and vaginal hyperemia (P<0.001). Nevertheless, the most accurate indicators of estrus that result in pregnancy were tail wagging and courtship behavior followed by standing estrus (P<0.05). According to the results obtained, 300 IU PMSG dose is sufficient, both to inseminate at a fixed time (43 to 45 h after sponge removal) and to record the estrus behavior by teaser male 24 h after sponge removal. Higher PMSG doses (400 to 500 IU) altered the timing of ovulation; specifically, 500 IU dose shortened the duration of estrus behaviors. In conclusion, even though the different doses of PMSG displayed similar effects on estrus synchronization and pregnancy rates, we concluded that tail wagging, courtship behavior and standing heat are the most reliable estrus signs for artificial insemination in Angora goat.

Use of the gonadotropin-releasing hormone (GnRH) stimulation test to monitor gonadal function in intact adult male cats

The gonadotropin-releasing hormone (GnRH) stimulation test is a common procedure used to investigate normality of the pituitary-gonadal axis in mammals. There is very little information on the technique, its efficacy and side effects in small animals and in particular no information for male cats. In dogs, such test is performed by intravenous (IV) administration. With cats, the number of times the animal needs to be restrained for blood sampling should be the least possible. The purpose of this study was to assess efficacy and side effects of the GnRH stimulation test in tomcats comparing the IV with the intramuscular (IM) route of administration. A GnRH stimulation test was performed in eight adult tomcats through IM or IV administration of 50 μg gonadorelin. The response of the pituitary-gonadal axis was assessed by measuring serum testosterone on blood samples collected prior to and 1 hr following treatment. When considering each single group of cats, the post-stimulation serum testosterone values were significantly higher than the pre-treatment ones (p < .05). When comparing the two groups of cats, basal testosterone concentrations did not differ, and also post-GnRH testosterone concentrations did not differ. In conclusion, in the cats of our study, the GnRH stimulation test produced the same results following the IM or the IV route of administration. Therefore, in tomcats, the IM route can be considered as effective as the IV one and should be preferred when doing a GnRH test.

Biochemical and protein profile of alpaca (Vicugna pacos) uterine horn fluid during early pregnancy

South American camelids show high embryo loss rate, during the first 60 days of pregnancy. One of the factors which may be related to this situation is that over 98% of the embryos implant in the left uterine horn (LUH) even though both ovaries contribute similarly to ovulation. There is scarce information about the uterine environment of female camelids at any physiological state that could explain the capability of the LUH to attract the embryo and maintain pregnancy. We describe, for the first time, the biochemical and protein profile of uterine fluid (UF), addressing the right and LUH environment in non-pregnant and pregnant alpacas. Different substrates, electrolytes and metabolites were assayed in both uterine horn fluids. Small changes were observed in glucose and total protein levels, which were more noticeable during pregnancy. In addition, 10 specific proteins were found in the left horn fluid in 5-week-pregnant alpacas, and two protein bands were identified in non-pregnant alpaca right horn fluid. These results would provide basic information for identification of possible markers for pregnancy diagnosis, reproductive diseases and hormone-treated animals evaluation and hence contributing to improve the pregnancy rate.

Integrated evaluation of scrotal temperature and testosteronemia after GnRH administration in young bulls with low semen production

The aim of this study was to determine the suitability of thermographic monitoring of scrotal surface temperature (SST) as a method to monitor testicular function. Yearling bulls (n = 23) with low semen production were selected. Scrotal surface temperature and serum testosterone (T) concentrations were evaluated before and after administration of 10.5 μg buserelin acetate IV. Thermographic images of scrotum were recorded at 0, 15, 30, 45 and 60 min post-GnRH, while blood sampling was only performed at 60 min post-GnRH. Bulls were divided in two groups: LowTemp bulls (n = 10) had a decreased SST at 60 min; HighTemp bulls (n = 13) had an increased SST. After 60 min, LowTemp bulls had higher T concentrations compared to HighTemp bulls: 14.32 ng/ml ± 0.53 vs 10.30 ± 1.37 ng/ml (mean ± SEM; p < 0.05), respectively. Reproductive performances in both groups improved after GnRH administration, resulting in an increased number of inseminating doses from each collection, which was higher in LowTemp bulls. Pearson correlation test showed a negative relationship between T and SST (r = -0.554). In conclusion, a decreased scrotal surface temperature 60 min after GnRH treatment was associated with improved semen production.

Alpaca semen quality in relation to different diets

The aim of the present study was to evaluate the biochemical composition of seminal plasma, along with semen quality, of alpacas maintained on different diets (hay; hay+pasture grazing; pasture grazing+sheep concentrate; pasture grazing+horse concentrate; Periods 1-4, respectively). Alpacas (n=5) were fed the four different diets for a period of 6 weeks each. During the period of feeding of each diet, semen was collected using an artificial vagina to determine its volume, viscosity, sperm concentration and sperm motility. Moreover, testicular volume and body condition score were evaluated. Seminal plasma was analysed biochemically to measure total protein, triglyceride, cholesterol, γ-glutamyl transferase, alanine aminotransferase (ALT) and alkaline phosphatase levels. Protein profiles were investigated using one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis. There was high variability in semen parameters between different males maintained on the same diet. Semen volume increased significantly (P<0.05) when alpacas were fed diets containing commercial sheep and horse concentrates. In contrast, sperm concentration and motility decreased significantly (P<0.05) from Period 1 to Period 4. Dietary changes had no effect on viscosity. Significant reductions were seen in triglyceride and cholesterol content, as well as γ-glutamyl transferase, ALT and alkaline phosphatase concentrations, from Period 1 to Period 4. Regardless of experimental period, a wide variation was seen in seminal plasma enzyme concentrations between alpacas, whereas diet had no effect on glucose and total protein concentrations in the seminal plasma. Eight protein bands, with molecular weights ranging from 200 to 14kDa, were considered in electrophoresis gel after image analysis. Proteins fractions of the 14-kDa (total protein express in mddL(-1) with a molecular weight of 14-kDa, TP8) and 21-kDa (total protein express in mddL(-1) with a molecular weight of 21-kDa, TP7) bands were not present in all samples of alpaca seminal plasma. There were no significant changes in the concentration of any protein fractions during the four periods. Moreover, the protein fraction of the 60-kDa (total protein express in mddL(-1) with a molecular weight of 60-kDa, TP3) band was the most prevalent in all periods. These results demonstrate that there are marked changes in semen quality, as well as some parameters related to the composition of alpaca seminal plasma, that are dependent on diet, which may indicate the need for specific diet formulation to improve reproductive performance. We hypothesise that, in alpacas, the mechanisms underlying the changes in some reproductive traits in response to feeding regimens could be related to changes in the endocrine-gonadal system.

Testicular cytology of alpaca: comparison between impressed and smeared slides

Testicular fine needle aspiration (TFNA) has proven to be a simple and minimally invasive procedure, which allows assessments of cytological parameters of seminiferous epithelium/tubules more accurately in a short time. Though this technique does not cause negative effects on sperm quality or any damage to testicular tissue, its use is very limited in male animal infertility diagnostics. Report on the use of this technique in South American Camelids (SAC) is very limited. Therefore, the aim of this study was to evaluate the efficacy of TFNA for identification of different testicular cells and cell indices, and their correlation with that of impression cytology. A total of 98 slides were prepared from testes of six adult alpaca males, collected immediately after slaughter. Aspiration samples were performed by inserting a fine butterfly needle (21 G) connected to a 50 ml syringe into a testicle and multiple plane aspirations were carried out to obtain the materials destined to the smear. Three different imprints on slides were taken from each testicle. All slides were air-dried, stained with modified May--Grünwald--Giemsa (MGG) stain and then examined under light microscope with 1000× magnifications. Spermatogenic cells such as, spermatogonia (Sg), primary spermatocytes, secondary spermatocytes, early spermatids (ab), late spermatids (cd) and spermatozoa, and Sertoli cells were counted. The spermatozoa percentage was expressed as spermatic index (SI) and the number of Sertoli cells, counted apart, was expressed as sertoli cell index (SEI). There was not any significant difference between the spermatogenic cell parameters obtained from the two types of slides, but SEI were significantly different in two types of smears. The results of the study provide support for the use of TFNA as a useful minimally invasive modality to identify different spermatogenetic cell classes in alpaca. Moreover, the possibility to standardize this method might provide a greater impulse to the clinical diagnostics of SAC male infertility.

Effect of an injectable cabergoline formulation on serum prolactin (PRL) and milk secretion in early postpartum Beagle bitches

This study was conducted in order to evaluate effects on prolactin (PRL) concentration and mammary milk secretion of an injectable cabergoline formulation administered to five lactating Beagle bitches during early postpartum (PP). Bitches were bled twice daily (from PP day 3 to PP day 12) and then daily (from PP day 13 to PP day 16) to assay serum PRL. On PP day 6, a subcutaneous (SC) injection of 0.1 ml/kg of placebo was administered. On PP day 9, a SC 0.1 ml/kg dose of injectable cabergoline was administered. All bitches were checked for milk production, using a clinical scoring in order to quantify milk expression from each teat. A circadian variation of serum PRL was evident during the 6 days of pre-treatment monitoring. The day after cabergoline injection, an 80% decrease of PRL serum concentration was observed (p < 0.05). The circadian oscillatory pattern of PRL secretion disappeared after administration of cabergoline, and PRL values remained significantly lower than in the previous days for the first 60 h following treatment (p < 0.001). Milk production was drastically reduced when comparing pre-treatment to post-treatment scores (p < 0.001). A single dose of injectable cabergoline caused a significant reduction in serum PRL concentration and a significant reduction in milk flow. The injectable formulation of cabergoline appeared to be safe and well tolerated.

Subacute rumen acidosis in lactating cows: an investigation in intensive Italian dairy herds

Subacute rumen acidosis (SARA) represents one of the most important metabolic disorders in intensive dairy farms that affects rumen fermentations, animal welfare, productivity and farm profitability. The aim of the present study was to study the occurrence of SARA in intensive Italian dairy herds and to determine the relationship between diet composition, ruminal pH and short chain fatty acids (SCFA) concentration. Ten commercial dairy herds were investigated; twelve cows in each herd were selected randomly among animal without clinical signs of disease, with good body condition and between 5 and 60 day-in-milk (DIM), to perform rumenocentesis and obtain rumen fluid. Ruminal pH was determined immediately after sampling and concentration of SCFA in ruminal fluid was determined on samples after storage. An other objective of this research was to study in detail the effects of rumenocentesis on animal health: this study could confirm the extreme validity of this technique as ruminal sampling. Results were subject to anova and correlation analysis using SIGMA STAT 2.03. The results indicated the presence of SARA in three herds (more than 33% cows with rumen pH < 5.5), a critical situation (more than 33% cows with rumen pH < 5.8) in five farms and a normal rumen pH condition in two herds. In particular, dairy herds show on average SCFA concentration of 150, 145, 123 mmol/l for low pH, critical pH and normal pH herds respectively. There were not significant differences among diet composition even if herds with SARA showed a light discordance between initially chemistry composition and residual feed. In the affected herds it was not possible to understand the exact causes of SARA. Animal management seems to be one of the most important factors in developing SARA including total mixed ration preparation.

Effect of levamisole administration on bluetongue vaccination in sheep

Levamisole is an anthelmintic drug with immunostimulant properties when administered at repeated doses of 2.5 mg/kg prior to a vaccine being administered. In order to assess the effect of levamisole administration on bluetongue (BT) vaccination in sheep, four groups of unvaccinated pregnant sheep (8 sheep per group) were used. Group A received vaccine only; Group B received levamisole+vaccine; Group C received Levamisole only; Group D was a non-treated control. Levamisole (Citarin L-10%) was administered three times weekly at an initial dose of 5.0 mg/kg of body weight and subsequently at 2.5 mg/kg of body weight. There was a significant decrease in faecal egg count of gastrointestinal strongyles in Groups B and C. At the beginning of the trial, all animals were serologically negative for BT antibodies; after vaccination, there was a difference in antibody response in animals in the treated groups. Significantly, more animals in Group B developed BT antibodies following vaccination than those in Group A. In conclusion, levamisole appeared to have an immunostimulating effect on the response of sheep to BT vaccination.