Sexual Rest Research Articles

Physical separation and reduction of contact duration with sexually hyperactive bucks decrease testosterone concentrations and sexual behaviour in bucks in sexual rest

Sexually hyperactive bucks are more efficient than sexually hypoactive bucks in stimulating testosterone secretion and sexual behaviour in other bucks in seasonal sexual rest by the phenomenon that we called the “buck-to-buck effect”. Here, we determined whether physical separation and reduction of the duration of contact with the sexually hyperactive bucks would modify those parameters in sexually hypoactive bucks exposed to the “buck-to-buck effect”. Bucks were subjected to natural day length throughout the study; this was the sexually hypoactive group. Other bucks were subjected to artificial long days (16 h of light per day) from 15 November to 15 January followed by exposure to natural day length to stimulate their sexual activity during the rest season; this was the sexually hyperactive group. In Experiment 1, we determined testosterone concentrations and sexual behaviour of six sexually hypoactive bucks separated 1.5 m from six sexually hyperactive bucks for 60 days by a metal open work fence, while a control group of six sexually hypoactive bucks was in permanent contact with six sexually hyperactive bucks. In Experiment 2, the duration of contact with sexually hyperactive males was reduced from 31 days (contact group, six bucks) to 10 days (withdraw group, seven bucks). In experiments 1 and 2, there was an effect of time (P < 0.01) and an interaction between time and groups (P < 0.05). In Experiment 1, testosterone plasma concentrations were greater in bucks in contact with sexually hyperactive bucks than in those separated from bucks at 20 and 30 days after the introduction of sexually hyperactive bucks (P < 0.01). The bucks from the contact group also displayed more nudging than bucks from the separated group from 0 to 30 days (P < 0.001). In Experiment 2, testosterone concentrations were greater in the contact group than in those from the withdraw group from 19 to 31 days after the introduction of sexually hyperactive bucks (P < 0.05). Bucks from the withdraw group displayed more nudging than the contact group 7 days after the introduction of the sexually hyperactive bucks (P < 0.05). Afterwards, bucks from the contact group displayed more nudging than the withdraw group 14, 21 and 28 days after the introduction of the sexually hyperactive bucks. We concluded that physical separation and reduction of the duration of contact with the sexually hyperactive bucks decrease testosterone concentrations and sexual behaviour of bucks in sexual rest exposed to the “buck-to-buck effect”.

Spermatic reserves in three South American camelids

Spermatic reserves were determined in three South American camelids: alpaca, llama, and vicuna. Reserves were determined at three different times: before the breeding season (November), after the breeding season (March and April), and during sexual rest (September). Three sexual organs: testicles, epididymis, and vas deferens were isolated from 12 alpacas, eight llamas, and a vicuna. Organs were weighed, and spermatozoa were collected into warmed tubes containing phosphate saline solution. Spermatic concentration was determined using the hemocytometer method. Data were analyzed using analysis of variance, and the Duncan test was used to assess differences, if any. There was a difference (P&lt;0.05) in spermatic concentration and reserves between llama (41, 98), alpaca (15, 27), and vicuna (0.4 million spz/organ, and 1.4 million spz/g tissue, respectively. Likewise, in alpacas, there was a difference (P&lt;0.05) in spermatic concentration and reserves by organs, being (47, 118 in the epididymis tail and 29 25 million for the vas deferens, respectively. Llama reproductive organs hosted more spermatozoa than alpaca and vicuna. The alpaca's spermatic reserves were not affected by the time of year. However, the epididymis tail and vas deferens contained more spermatozoa than any other reproductive organ.

Peculiarities of the effect of zinc chelate on prooxidant-antioxidant homeosta-sis in the blood of sows and their relationship with the reproductive capacity

During the last decades, research has been actively conducted to increase the reproductive capacity of sows. It was determined that during puberty, the sow’s body actively assimilates nutrients that should provide for their own needs and embryos and creates a reserve for the lactation period. The study aimed to determine the influence of zinc in the form of chelate on the state of prooxidant-antioxidant homeostasis on the reproductive capacity of sows. In the experiment, 45 heads of the Large White breed sows were used, and they were selected and divided into groups (5 heads each) according to the principle of analogs. The norms fed barren and farrowing sows according to their physiological state. The diet of the control group of sows from sexual rest to the 28th day of farrowing remained unchanged; the 1st experimental group – MD+5 % Zinc in the form of zinc chelate, the II experimental group – MD+10 % Zinc in the form of Zinc chelate. Additional feeding of biologically active compounds was stopped one day before farrowing. During the phase of sexual rest, estrus, on the 90th and 104th days of farrowing, the day of farrowing, as well as on the 5th and 28th days of the suckling period, blood was taken from sows and their piglets to determine the state of PAH. It has been determined that in the blood of sows, the periods of the reproductive cycle determine the peculiarities of the formation of prooxidant-antioxidant homeostasis. In particular, during estrus, there is an intensification of peroxide oxidation processes – the content of diene conjugates increases by 56.9 %, TBC-active compounds by 12.3 %, and the level of low molecular weight antioxidants – reduced glutathione decreases (Р &lt; 0.001). This is accompanied by a significant increase in the activities of antioxidant enzymes – superoxide dismutase (Р &lt; 0.05) and catalase (Р &lt; 0.05). It was found that the intensification of peroxide oxidation processes is intensified on the day of farrowing of sows – the content of diene conjugates increases by 26.6 % and TBC-active compounds by 31.8 % with a further decrease during lactation to the level of sexual rest. Animals that received zinc in the form of zinc chelate 5 % above the norm were characterized by a lower intensity of peroxide oxidation processes. Additional feeding of zinc in the form of zinc chelate to sows by 10 % more than the norm is accompanied by a decrease in fertility (Р &lt; 0.05), the number of live piglets (Р &lt; 0.05), litter weight at birth by 10.0 % and litter weight at weaning – 11.6 %. Sows that received this feed supplement of microelement 5 % above the norm are characterized by higher fertility by 4 % and litter weight at birth by 4.2 %.

Surgical Management of Prepucial Prolapse in 6 – Male Breeding Bulls

6 - Male breeding bulls were presented to VCC of CVAS Bikaner with the history of preputial prolapse and its hardening and paraphemosis. All the six breeding bulls under study had similar anatomical injury and had IV degree prolapse. Initially medicinal treatment was carried out in all bulls to reduce the swelling and infection. In all the animals antibiotic injection Streptopenicillin 5.0 g IM was given for 5 days and; injection Meloxicam @ 0.2 mg/kg IM for 3 days and antiseptic dressing of the prepuce was done with Povidone iodine solution for 5 days to reduce the infection and thereafter surgery was performed. Preputial prolapse was repaired successfully via circumcision technique. After the surgery all bulls were given 60 days of sexual rest. No post-operative complications and recurrence were recorded.

Exploration of semen quality analyzed by casa-mot systems of brahman bulls infected with BLV and BHV-1

Enzootic bovine leukosis virus (BLV) and bovine herpesvirus 1 (BHV-1) are very important infectious agents for the livestock industry worldwide. The present study aimed to explore the association between natural exposure to BLV and BHV-1 with sperm quality analyzed by Computer-Assisted Semen Analysis (CASA) systems. Ten sexually mature Brahman bulls, with sanitary status BLV+/BHV-1+ (n = 2), BLV−/BHV-1+ (n = 6) and BLV-/BHV-1- (n = 2) were evaluated twice, 30 days apart. Results showed that sanitary status of each bull was not associated with semen quality. It was found that the quality of the semen from the second collection was better due to the interruption of sexual rest. The evidence thus revealed that a bull infected with BLV generated good-quality contaminated semen and, therefore, that it is essential to detect contaminated seminal samples to prevent the spread of BLV. A multivariate analysis showed the presence of four sperm subpopulations in Brahman bulls that differ significantly in their kinematic patterns and with respect to sanitary status (P < 0.05), indicating that infection-free and seronegative bulls present the best kinematic parameters, which improved discrimination of sperm quality according to sanitary status. Overall, the analyses indicate that the seropositive-infected bulls with BLV and BHV-1 should be excluded from beef cattle farms.

Bovine reproductive immunoinfertility: pathogenesis and immunotherapy.

Infertility is one of the primary factors for cattle reproduction in the present scenario. Reproduction-related immunoinfertility mainly involves immunization against the antigens related to reproductive hormones (LHRH, GnRH, Gonadal steroids, PGF2α and oxytocin), spermatozoa, seminal plasma and ovum. Anovulation, delayed ovulation, sperm immobilization, failure of fertilization, prolonged uterine involution, extended calving interval, prolonged post-partum estrus and reduced conception rate could be a result of immunoinfertility that occur due to the blockage of receptor site by antibodies formed against hormones, sperm and ovum. Immunoinfertility can be treated in the animal by giving sexual rest to females, by using various reproductive technologies such as in-vitro fertilization, gamete intra fallopian tube transfer, and intracytoplasmic sperm injection, sperm washing and by treating the animals with immunomodulators such as LPS, Oyster glycogen, etc. This review summarizes the different causes of bovine reproductive immunoinfertility and amelioration strategies to overcome it.

Oxidative stress associated with proteomic and fatty acid profiles of sperm from Nellore bulls at rest†.

Sexual rest is a transient condition, which compromises conception rates, characterized by large volumes of ejaculate with high percentages of dead sperm observed in bulls. The biochemical mechanisms leading to this ejaculate pattern are not fully understood. Six adult resting Nellore bulls were submitted to Breeding Soundness Evaluation by four consecutive semen collections through the electroejaculation method during a 30min period. Each ejaculate had its semen phenotypic parameters; morphology and physical aspects were evaluated. To assess enzymatic activity (superoxide dismutase, catalase, and glutathione S-transferase), lipid peroxidation (concentrations of malondialdehyde and nitric oxide), fatty acid, and proteomic profile aliquots of spermatozoa from the first and fourth ejaculates were used. All sperm parameters differed between the first and fourth ejaculates. Spermatozoa from the first ejaculate showed lower enzymatic activity and a higher concentration of lipid peroxidation markers. Among the 19 identified fatty acids, 52.7% are polyunsaturated. Relative abundance analysis showed that C12:0 and C18:0 fatty acids differed between the first and fourth ejaculates, being the fourth ejaculate richer in spermatozoa. The proteomics analysis identified a total of 974 proteins in both sample groups (first and fourth ejaculates). The majority of identified proteins are related to cellular processes and signaling. Quantitative proteomics showed 36 differentially abundant proteins, 6 up-regulated proteins in the first ejaculate, and 30 up-regulated proteins in the fourth ejaculate. Spermatozoa from bulls at sexual rest have less antioxidant capacity, causing changes in their fatty acid composition and protein profile, which generates the observed sperm pattern and lower fertilization capacity.

Semen quality of rams fed a liposomal vitamin-mineral supplement during the period of sexual rest

To increase the sexual activity and sperm quality of rams during the period of sexual rest, it is necessary to increase the consumption rates of vitamins and microelements to the level of the mating season. The aim of the work was to find out the effect of feeding a liposomal vitamin-mineral supplement on the quality parameters of ram sperm during the period of sexual rest. The experiment was conducted on 12 clinically healthy Texel rams, aged 2–4 years, during the period of sexual rest (March–May). Animals were divided into two groups: control and experimental, 6 heads each. The control rams received the basic diet, the animals of the experimental group were individually added to the combined feed for 45 days with a feed additive in the form of a liposomal emulsion, which included: vitamins A, D3, E, C and zinc gluconate. After the end of supplement feeding, ejaculates were collected from the rams for research. The motility, kinetic indicators of sperm, the activity of succinate dehydrogenase (SDH) and cytochrome oxidase (CO) in sperm, as well as the activity of antioxidant protection enzymes superoxide dismutase (SOD), glutathione peroxidase (GPO) and catalase (CAT) were determined. It was established that feeding liposomal vitamin-mineral supplement to rams during the period of sexual rest significantly (P &lt; 0.05) increases sperm activity, their kinetic indicators: curvilinear (VCL), straight-line (VSL) and average speed (VAP) of sperm movement (P &lt; 0.05–0.001), the activity of enzymes – markers of the fertilizing capacity of SDH and CO sperm (P &lt; 0.05–0.001). At the same time, there was a significant (P &lt; 0.05) decrease in the activity of SOD with a simultaneous significant (by 23.3–25.0 %) increase in the activity of GPO and CAT (P &lt; 0.01). Higher indicators of the quality of ejaculates of rams under the influence of vitamins A, D3, E, C and zinc gluconate indicate the possibility of obtaining high-quality sperm from breeding rams during the period of sexual rest.

Effect of the GnRH stimulation test on Canine Prostatic-Specific Esterase (CPSE).

The gonadotropin-releasing hormone (GnRH) stimulation test is used to investigate testicular production of testosterone (T) when performing a breeding soundness examination. In male dogs with fertility problems, the prostate should also be investigated as prostatic conditions may frequently lower semen quality. Serum concentrations of canine prostatic-specific esterase (CPSE) increase in dogs with benign prostatic hyperplasia (BPH). When performing a breeding soundness examination in a male dog, GnRH administration is frequently done at the beginning of the process and then both T and CPSE are assayed on the same serum sample collected 1 h following the GnRH injection. The aim of this study was to assess whether or not the administration of GnRH may alter CPSE concentrations in dogs with a healthy prostate. Twenty-eight client-owned intact adult male dogs were included in the study. Following a 7-day sexual rest all male dogs underwent a clinical examination and an ultrasonographic examination of the prostatic gland. Prostatic size and parenchyma of every tested dog were evaluated by ultrasonography to assess prostatic conditions. Two different GnRH stimulation protocols were used, A = gonadorelin 50μg/dog SC (n = 15) and B = buserelin 0.12 μg/kg IV (n = 13). T and CPSE concentrations were measured before and 1 h after GnRH administration by a laser-induced fluorescence analysis. Buserelin and gonadorelin were equally effective in causing a significant increase in serum T concentrations in the post GnRH sample. When considering the 28 dogs together, CPSE concentrations did not change following the stimulation test with either GnRH compound; however, in 4/28 cases, the post GnRH value was markedly increased to values compatible with a diagnosis of BPH. There was no difference in the action of buserelin or gonadorelin in causing an increase in serum T concentrations. CPSE secretion was increased in approximately 15% of dogs treated with either buserelin or gonadorelin. Therefore, whenever performing diagnostic testing in intact male dogs, CPSE should not be assayed on a post-GnRH serum sample.

Study of Estrus Induction in the Female Dog by PMSG and HCG

Our study, spread over four (4) months (February to June), aims at heat induction and monitoring within a population of 10 female dogs of different breeds (German shepherd, Rottweiler and Pit-bull). Aged from 2.5 to 4.5. Two of them were used as controls. To do this, we carried out the following investigations: Monitoring the sexual cycle of the female dogs, prior to heat induction, by gynecological and cytological examination (vaginal smears) to confirm the sexual rest phase (anestrus); hormonal induction of heat by PMCG and hCG; monitoring the induced heat by the vaginal smear method (Giemsa stain); and a breeding of female dogs in estrus confirmation of the pregnancy of the mated female dogs (palpation and ultrasound) by comparing the vaginal smears of the treated female dogs with those of the control female dogs. At the end of our study, the results obtained were encouraging, since we succeeded in obtaining the appearance of heat in 60% of the treated female dogs.

Effect of Uterine Lavage, Levamisole, PGF2α and its Combinations on Haematological Indices and Bacterial Load in Estrual Mucus of Endometritic Buffaloes

The objective of this study was to compare uterine lavage, Levamisol s/c, PGF2α i/m and its combinations on haematological indices, bacterial load in cervico-vaginal mucus (CVM) and therapeutic response in endometritic buffaloes. Thirty six repeat breeder buffaloes were randomly assigned into six equal groups. Six animals were kept as positive control (no treatment, only sexual rest, T0 ), and the rests were assigned to five treatment group, i.e., T1 (uterine lavage), T2 (Levamisol SQ ), T3 (PGF2α IM ), T4 (uterine lavage plus Levamisol s/c) and T5 (uterine lavage plus PGF2α IM ). Significant (p&lt;0.05) decline in bacterial load and TLC values were recorded after treatment over pretreatment ones in all five treatment groups. Furthermore, Hb, TEC and PCV increased significantly after treatment as compared to control one. Significant drop in neutrophils and rise in lymphocytes was recorded post-treatment in all treatment groups. The eosinophil, basophil and monocytes did not differ significantly within and amongst the groups. The therapeutic response was 33.33, 50.00, 66.67, 66.67, 83.33 and 83.33% in T0, T1, T2, T3, T4 and T5, respectively. The corresponding conception rates were 16.67, 33.33, 50.00, 50.00, 66.67 and 66.67 %. The results conclude that, uterine lavage along with Levamisol or PGF2α can be used effectively to manage endometrtitic buffaloes.

Variation of ewe olfactory secretome during a ram effect.

Under temperate latitudes, reproduction in Ovis aries displays a marked seasonality, governed by the photoperiod. In natural conditions, the transition between sexual rest and sexual activity in both sexes is induced by the decrease of day light. Meanwhile, specific odors emitted by a sexually active male are able to reactivate the gonadotropic axis of anovulatory ewes. This physiological effect is called "male effect", precisely ram effect in the ovine species. We have previously shown that the secreted proteins, namely Olfactory Binding Proteins (OBP), contained in the nasal mucus constitute the olfactory secretome (OS), the composition of which is determined by the status of oestrus cycle of females and differs between sexual rest and sexual activity periods. The objective of this study was to test the hypothesis that exposure to sexually active male can also modify the composition of ewes olfactory secretome during a male effect, as well as hormones produced by the reactivation of the oestrus cycle in sexual activity period under natural conditions. We have set up a new non-invasive protocol of nasal mucus sampling and collected it from 12 ewes at different times during a ram effect. We analyzed the composition of their olfactory secretome by proteomics, mainly SDS-PAGE and MALDI-TOF mass spectrometry. As post-translational modifications of OBPs were a hallmark of ewes' sexual activity period, we were looking for glycosylation by western-blot and mass spectrometry. The efficiency of male effect was low in stimulated ewes as only 3 females displayed elevated progesterone levels in their blood. Besides, half of control ewes (non-stimulated ones) were cycled. We noticed a common OS profile in ewes in anoestrus, versus OS of cycled ones. A very clear and important result was the apparition of O-GlcNAcylation, previously detected only in sexual activity, after only 30 min of male introduction into the flock. This exploratory study paves the way for further experiments with larger flock to confirm and reinforce these results, and for eventually exploiting the nasal mucus as an indicator of females' receptivity to male odors.

Rams sexually activated in spring by light treatment stimulate social and sexual activities in non-activated rams

Twelve rams were used to confirm whether rams sexually activated in spring by light treatment increase social and sexual activities of non-treated rams in the presence of ewes. Males were divided into 2 groups: light-treated rams (group L, n = 6), which were exposed to artificial long days (16 h light) for 2 months (1 Nov-31 Dec), or non-exposed, control rams (group C, n = 6), exposed to the natural photoperiod. At the end of the long-day period, light-treated rams were returned to the natural photoperiod, groups isolated from each other. In mid-Feb, 3 rams from each group were put together such that 4 experimental groups were created: the remaining light-treated rams (L, n = 3), the remaining control rams (C, n = 3), and the other treated (L-mixed n = 3) and non-treated (C-mixed, n = 3) rams, exposed to 30, 30, and 60 ewes, respectively, in 3 separate paddocks. To identify each ram, large (30-cm-high) numbers were painted on the sides and rump of the males with washable sheep spray paint. Behaviors were documented by 4 video cameras using 6 30-minute segments from 1600 to 1800 h the following day (27 hours). C rams presented the lowest proportion of activities (P < 0.01), and C-mixed rams exhibited proportions similar to L and L-mixed rams. C rams exhibited the fewest fight attempts (P < 0.001), fighting (P < 0.05), pushing (P < 0.001), and sniffing another ram. The groups differed significantly (P < 0.001) in pushing, pawing, flehmen, and attempt mounting, and C rams had the fewest interactions. In conclusion, rams exposed to 2 months of long days at late-autumn early-winter increased social and sexual activities of unexposed rams. These observations can be explained by a “ram-to-ram effect”, which can enhance the endocrine activity of rams in sexual rest if they are joined with rams who have been made sexually active by a photoperiodic treatment. These findings suggest that socio-sexual interactions could be used to restrict out-of-season reproduction in this species.

Гематологічні показники та якість сперми баранів у період статевого спокою за згодовування ліпосомальної вітамінно-мінеральної добавки

The aim of the work was to investigate the effect of feeding a liposomal vitamin and mineral supplement during the period of sexual rest on hematological indicators and quality of ram sperm. The experiment was conducted at the PE “Kogut BM” in Horodotsky district, Lviv region, on 12 clinically healthy Texel rams, aged 2–4 years, during the period of sexual rest (March-May). Animals were divided into two groups — control and experimental, 6 animals per group. The control rams received the basic diet containing hay, corn silage, and compound feed. For 45 days, the sheep of the experimental group were individually added to the combined feed a feed additive containing vitamins A, D3, E, C and zinc gluconate in the form of a liposomal emulsion. At the beginning and at the end of feeding, we took blood samples, in which hematological indicators were determined. After the end of supplement feeding, ejaculates were collected twice a week in doublets for three weeks. Physiological indicators of ejaculate quality (volume, sperm concentration, percentage of live sperm, as well as sperm viability, morphological disorders and percentage of degenerative sperm) were determined using the CASA computerized system. It was established that feeding liposomal vitamin-mineral supplements to rams during the period of sexual rest improves hematological indicators: the content of erythrocytes, hemoglobin, platelets and hematocrit increase significantly (P&lt;0.05–0.001) while the content of leukocytes decreases by 24.2% (P&lt;0.05). Accordingly, the erythrocyte indices of the blood of experimental breeding rams were higher than those of control animals. Feeding rams with a liposomal vitamin and mineral supplement ensured an increase in ejaculate volume by 17.6% (P&lt;0.05), sperm concentration (P&lt;0.01), their viability, as well as a decrease in the number of immature (P&lt;0.001) and degenerated (P&lt;0.05) sperm. Higher quality indicators of ejaculates of rams under the influence of vitamins A, D3, E, C and zinc gluconate indicate the possibility of obtaining sperm from breeding rams during the period of sexual rest.

Seminal quality comparison of first and second cryopreserved ejaculates of Alpine kid goats by flow cytometry.

Discarding the first ejaculate is recommended as an alternative for improving seminal quality after long sexual resting, especially when semen should be used for cryopreservation. However, when the males are not in sexual resting the necessity to discarding the first ejaculate is still unknown. Therefore, this study aimed to compare by flow cytometry the quality of the first and second ejaculates. Ten kids and uniform goats between 5 and 6 months of age were used in a completely randomized design. Semen collection was carried out every 4 days, until a total of five ejaculates per animal in each treatment was completed. The fresh and frozen semen collected were processed and analyzed using macroscopic and microscopic parameters, resistance test, hypo-osmotic medium test, and flow cytometry (FC). The FC parameters were production of reactive oxygen species, plasma and acrosomal membrane integrity, and lipid peroxidation of the plasma membrane. The ejaculates did not differ for the resistance test, the reactivity in the hypo-osmotic medium and for the macroscopic and microscopic seminal parameters, except for sperm volume and concentration. The first ejaculate had a higher percentage of minor and total defects. None of the FC parameters analyzed differed between the first and second ejaculates. The first and second ejaculates demonstrated similar seminal qualities, so for Alpine kid goats without a sexual resting period, discarding the first ejaculate it is not recommended.

Exposure of rams in sexual rest to sexually activated males in spring increases plasma LH and testosterone concentrations

Eight stimulating rams, and twelve stimulated rams, were used to determine whether a similar endocrine response to the introduction of sexually active males in spring in a flock of ewes is observed in a flock of rams. The stimulating rams (n = 4) were induced into a sexually active state by exposure to 2 months of long days (16 h light/d) (15 December-15 February). At the end of the long-day period, rams were returned to the natural photoperiod. Control-stimulating rams (n = 4) were kept under the natural photoperiod. On April 20, stimulated rams were divided into 2 groups, and joined with activated (ACT; n = 6) or control stimulating rams (C; n = 6). On the day of ram introduction, stimulated rams were blood sampled for 8 h at 20-min intervals, from 4 h before to 4 h after ram introduction, and next day from 24 to 28 h after ram introduction, and analyzed for plasma LH concentrations, and 10, 20 and 30 days after ram introduction to measure plasma testosterone levels. Mean (±SEM) plasma LH concentrations (ng/ml) of stimulated rams were similar during the 4 h before stimulating-ram introduction (ACT: 0.59 ± 0.03; C: 0.53 ± 0.04; P > 0.05). The introduction of the photoperiod-treated stimulating rams increased LH concentrations of stimulated rams during the 4 h after their introduction (1.14 ± 0.37) compared with the C group (0.51 ± 0.03; P < 0.05), especially during the first hour (ACT: 0.93 ± 0.16; C: 0.49 ± 0.03; P < 0.05), and during the blood sampling period 24–28 h after ram introduction (0.75 ± 0.07 vs. 0.58 ± 0.04; P < 0.05). Before the introduction of stimulating rams, the LH pulse frequencies and amplitudes did not differ between groups; however, LH pulsatility was higher at 4 h (0.58 ± 0.11 pulses/h; P < 0.05), and had trend to be higher 24 h (0.50 ± 0.06) (P = 0.10) after the introduction of the photoperiod-treated stimulating rams compared with the control-stimulating rams (0.29 ± 0.08 and 0.29 ± 0.10, respectively). As for LH pulses, there was an effect of group (P < 0.05) on LH amplitude, which presented a trend to be higher in ACT rams 4 h after ram introduction (1.68 ± 0.30; P < 0.10) and higher 24 h (1.07 ± 0.08; P < 0.05) after ram introduction, compared with LH amplitudes of C rams (0.71 ± 0.06 and 0.82 ± 0.07, respectively). Plasma testosterone concentrations of rams exposed to photoperiod-treated activated rams were higher than those of rams exposed to control-stimulating rams, at 4 h, 20 and 30 days after ram introduction (P < 0.05). In conclusion, sexually active rams in spring are able to stimulate LH and testosterone secretion of other rams in sexual rest, a phenomenon we called “ram-to-ram effect".

Sexually active male goats stimulate the endocrine and sexual activities of other males in seasonal sexual rest through the “buck-to-buck effect”

Male goats rendered sexually active by exposure to a photoperiodic treatment are more efficient than untreated goats in stimulating LH secretion and ovulation in seasonally anestrous goats. This phenomenon is called the "male effect." Here, we determined whether sexually active bucks are able to stimulate the endocrine and sexual activities of other bucks in seasonal sexual rest through the phenomenon that we called the "buck-to-buck effect." We used bucks rendered sexually active (SA) during sexual rest by exposure to 2.5 mo of artificial long days (16 h of light per d) and untreated, sexually inactive (SI) bucks. In Experiment 1, we determined the short-term (21 d) LH and testosterone responses of sexually inactive bucks joined with a SA or SI buck. In Experiment 2, we determined the long-term (60 d) testosterone and sexual behavior responses of sexually inactive bucks joined with 2 SA or SI bucks. In Experiment 3, we determined the efficacy of bucks initially exposed to the buck-to-buck effect, the SABB bucks, to thereafter induce a “classical” male effect in seasonally anestrous goats. In Experiments 1 and 2, there was an interaction between time and groups in LH and testosterone plasma concentrations (P < 0.01). In Experiment 1, plasma LH concentrations were greater in bucks joined with a SA buck than in those joined with an SI buck (P < 0.05). In Experiments 1 and 2, testosterone concentrations were greater in bucks joined with SA bucks than in those joined with SI bucks (P < 0.05). In addition, in Experiment 2, the sexually inactive bucks joined with SA bucks displayed more nudging than those joined with SI bucks (P < 0.001). In Experiment 3, kidding rates did not differ between females joined with SA (34 of 40: 85%) or SABB bucks (32 of 40: 80%; P > 0.05). We concluded that the endocrine and sexual activities of bucks during sexual rest can be stimulated by SA bucks. In addition, SABB bucks are able to stimulate the reproductive activity of seasonally anestrous goats.

Using Mediterranean Mussel Bio-Indicators to Assess the Initial Health State of Ecosystems Receiving Desalination Plant Effluents in Agadir Bay (Morocco)

Elazzaoui, A.; Kalla, Y.; Lefrere, L.; Bouhaimi, A., and Moukrim, A., 2022. Using Mediterranean mussel bio-indicators to assess the initial health state of ecosystems receiving desalination plant effluents in Agadir Bay (Morocco). Journal of Coastal Research, 38(1), 154–167. Coconut Creek (Florida), ISSN 0749-0208. Mussels are often used as a biological bio-indicator for the quality assessment of marine ecosystems. Adopting this approach, the present work aims to study the initial health status of two ecosystems in Agadir Bay, Morocco expected to receive seawater desalination plant effluents. This study was conducted between February 2015 and March 2017 in two stations, Tifnit-Douira and Cap Ghir. In addition to the gametic development, variations of sex ratio and gonadal index were also determined. The reproductive cycle of Mytilus galloprovincialis is spread throughout the year. Under natural conditions, three collective spawning periods were observed. The main one was during the spring and the two other periods were optional and were in winter and summer. Variations of seawater temperature can make some changes in mussel spawning, with one principal period lasting during spring and summer and the optional one during winter. In both studied stations, sexual rest was manifested by a small percentage of the population particularly during summer, and could not reach the whole population at the same time. This finding is consistent with the gonadal index that never reached the value of 1. A unique hermaphroditism case was revealed in Tifnit-Douira mussels, and it remained statistically insignificant. The sex ratio was perfectly balanced in both stations and was in favour of males. The gonad histology did not show any cellular abnormalities in the germinal tissue. These results are of great importance since they characterize the current state of the studied stations area before the installation of the desalination plant. This state must be maintained after installation in order to preserve the typical halieutic resources of these ecosystems. The present findings confirm the good environmental health status and the aquaculture potential of Agadir Bay, especially in the north ecosystems (Cap Ghir) due to upwelling-nutritional intake and optimum seawater temperature.

Biometry, size structure and reproductive cycle of the sanded sea cucumbers Holothuria poli (Echinodermata, Holothuriidae) from the west Algerian coast

ABSTRACT The aim of this work is to study the biometric and reproductive characteristics of a population of Holothuria poli from the west Algerian coast. The study was carried out on 256 individuals (33.25 ± 12.38 g wet weight and 196.44 ± 37.81 mm relaxed length) collected from Oran Bay between October 2016 and September 2017. All individuals showed negative allometric growth (b = 1.586) and the population had a sex ratio of 1: 1 (male: female). Sexual maturity occurred at a relaxed length of 137 mm and at gutted body weight of 18 g. Macroscopic examination of the gonadal tubules revealed four sexual maturity stages (growth, maturity, spawning and post-spawning) and a reproductive pattern characterized by a single summer spawning period and autumnal sexual rest. The obtained data may constitute a database for the management of natural stocks of this sea cucumber species in Algerian waters.

КРИОРЕЗИСТЕНТНОСТЬ СПЕРМЫ ЖЕРЕБЦОВ В РАЗНЫЕ МЕСЯЦЫ ГОДА

It is known that the seasonality of reproductive function is much more pronounced in mares than in stallions. The mare goes through an anestrus period in autumn and winter, while spermatogenesis in stallions continues throughout the year. Therefore, studies of cryoresistance of stallion sperm in different months of the year are relevant. The aim of the study was to study the cryoresistance of stallion sperm in different months of the year when creating cryopreservation of genetic material with intensive breeding use of sires. The cryoresistance of the sperm of stallions with their intensive breeding use was the best from September to December during sexual rest. The highest incidence of sperm was in December, which is 0.44% more than in October, 5.12% more than in November, 7.62% more (P&lt;0.05) than in September, 20.53% more (P&lt;0.01) than in January, 27.3% more (P&lt;0.01) compared to February, 52.7% more (P&lt;0.001) than in March, 137.9% more (P&lt;0.05) than in April, 34.12% more (P&lt;0.001) than in May, 23.5% more (P&lt;0.001) than in June and 59.7% more (P&lt;0.001) than in July. The survivability of sperms after thawing in a thermostat at 37°C for less than 3 hours was observed in March, April and July. The lowest sperm motility after defrosting was observed in April, which is 36.4% less (P&lt;0.001) than in July, 38.6% less (P&lt;0.001) than in May, 45.12% less (P&lt;0.001) than in June, 50.1% less (P&lt;0.001) than in in January, 52.6% less (P&lt;0.001) than in February, 43.75% less (P&lt;0.001) than in March, 53.8% less (P&lt;0.001) than in September, 55% less (P&lt;0.001) than in October, 54.4% less (P&lt;0.001) than in November and 54.1% less (P&lt;0.001) than in December. Based on the data obtained on the mobility of deconserved sperm doses, we mat expect the highest fertility from the genetic material that is harvested from September to December.