An Experimental Model to Study Resistance Index and Systolic/Diastolic Ratio of Uterine Arteries in Adverse Canine Pregnancy Outcome

The aim of this study was to describe the changes in the resistance index (RI) and systolic/diastolic ratio ( S / D ) of the uterine arteries during mid-pregnancy abortion induction in the dog. Sixteen 30–35 day pregnant bitches were randomly assigned to either a pharmacological protocol to interrupt gestation (n = 8) or were used as untreated control group (n = 8). Doppler assessments of uterine arteries blood flow were carried out before the initiation of the protocol and then every other day up to abortion (treated group) or parturition (control group). All treated bitches aborted 6 ± 1.2 days after initiation of the treatment (while none of the non-treated bitches aborted). Pre-treatment RI and S / D did not differ between groups (p > 0.2) while average post-treatment indexes were (mean ± SD): 0.62 ± 0.1 vs 0.53 ± 0.1 (p < 0.01) and 2.96 ± 0.9 vs 2.23 ± 0.3 (p = 0.01), for the treated and non-treated group respectively. Correlations between days to abortion and RI or S / D were 0.75 (p < 0.01) and 0.79 (p < 0.01) and, −0.78 (p < 0.01) and −0.73 (p < 0.01) for the treated and non-treated groups respectively. In the treated group, correlations between serum progesterone (P₄) concentrations and RI and S / D were −0.76 (p < 0.01) and −0.59 (p < 0.01) respectively. It is concluded that, during induction of abortion, RI and S / D of uterine arteries progressively increased while P₄ decreased.     

Adaptation of protein oxidation to protein intake in the domestic cat

It is well-accepted that cats require more dietary protein than omnivores and herbivores. Work on hepatic enzyme activities showed that cats lack the ability to regulate the urea cycle enzymes in response to the dietary supply of protein. It was thus hypothesized that the high protein requirement of cats is due to an inability to regulate these enzymes, limiting adaptation to a low protein diet. We used indirect respiration calorimetry to assess the in vivo ability of cats to adapt substrate oxidation to different levels of dietary protein, including one below their protein requirement. In random order, eight cats consumed each of four semi-purified diets containing 7.7% (LP), 14.6% (AP), 27.3% (MP) and 51.1% (HP) of ME from protein. Cats consumed each diet for at least 14 days and then completed a 5-day nitrogen balance trial and at least 2, 12-hour indirect calorimetry measurements. The data were analyzed by anova using the Mixed procedure of SAS and are expressed as mean ± SEM. There was a significant effect of diet on protein oxidation (p < 0.0001), measuring 9.8 ± 0.5%, 13.4 ± 0.9%, 23.5 ± 0.8% and 49.0 ± 1.8% of total energy expenditure on the LP, AP, MP and HP diets, respectively. The ratio of protein oxidation/protein intake was significantly higher with the LP diet (1.27 ± 0.07) than the other three diets (AP, 0.92 ± 0.06; MP, 0.86 ± 0.03; HP, 0.96 ± 0.04; p < 0.0001), indicating a net loss of protein on the LP diet. Thus, cats adapted to a wide range of dietary protein concentrations, but were unable to fully adapt to the LP diet.     

Incubation of Post-Thaw Epididymal Cat Spermatozoa with Seminal Plasma

In domestic cats, epididymal spermatozoa have lower initial motility and viability than ejaculated spermatozoa and it is possible that seminal plasma compounds are behind these effects. The aim of this study was to investigate whether co-incubation of post-thaw epididymal cat spermatozoa with seminal plasma was able to improve sperm quality. Epididymal cat spermatozoa from 11 cats were cryopreserved. After thawing, each sperm sample was divided into two aliquots, centrifuged and incubated with two different media; Tris buffer (control) or pooled seminal plasma (treatment). Sperm quality was observed at 0, 2, 4 and 6 h after incubation. The results demonstrated that all of the sperm parameters except acrosome integrity were lower in the treatment group compared to the control group (p < 0.05); the percentages of motility (46.4 ± 15.4 vs 40.0 ± 9.4), the scores of progressive motility (3.1 ± 0.4 vs 2.8 ± 0.5), the percentages of spermatozoa with intact plasma membrane (46.3 ± 9.7 vs 39.6 ± 8.9) and intact acrosome (36.5 ± 16.2 vs 32.9 ± 15.1), as well as at all time points. In conclusion, the seminal plasma seems less beneficial to the post-thaw epididymal cat spermatozoa than the Tris buffer.     

Reproductive Parameters and Efficiency of Inseminators in Dairy Farms in Portugal

This study was carried out to determine the reproductive efficiency indices of one of the largest dairy co-operatives of northern Portugal, using data from 1980 to 1998. Records were made available by the computerized National Recording System. Age at first calving was 32.0 ± 6.0 months. Mean calving to first AI interval was 95.4 ± 30.0 days, and calving to conception intervals decreased (p < 0.05) from 176.9 ± 4.5 to 148.1 ± 5.6 days from the first to the fourth/fifth parturitions, respectively. Calving intervals decreased (p < 0.05) from 418.1 ± 3.4 to 392.5 ± 7.0 days from the first to fourth/fifth parturitions, respectively. Mean non-return rates at 90 days for first inseminations was 71.7 ± 6.5% and mean calving rates at first insemination was 51.4 ± 8.1%. There were significant differences (p < 0.001) in the inseminators' efficiency, measured by both non-return and calving rates at first AI, with differences between the best and worst results of 13.3 and 16.1% for non-return and calving rates, respectively. The ranking of the inseminators did not coincide when their efficiency was measured by either non-return or calving rates. The mean number of inseminations per pregnancy (pregnant cows only) was 1.4 ± 0.7 with significant (p < 0.001) differences among herds. The mean heat detection rate was 38.1 ± 16.9%, with highly significant (p < 0.001) differences among farms (ranging from 14.2 to 60.8%). Negative (p < 0.001) correlations were found between heat detection rate and calving to first AI, calving to conception and calving intervals. The meaning of these indexes for assessment of reproductive efficiency in the studied system, is discussed.     

Recovery and Cryopreservation of Epididymal Sperm of Plains Bison (Bison bison bison) as a Model for Salvaging the Genetics of Wood Bison (Bison bison athabascae)

The objective of this study was to optimize recovery and cryopreservation of epididymal sperm from plains bison, as a model for wood bison. In Phase 1, cauda epididymides were recovered from bison (n = 14) immediately after slaughter, minced and incubated in Sp-TALPH buffer for 3 h at 36°C. The resulting sperm suspensions were cryopreserved in Triladyl^®, using a protocol for bovine semen. In Phase 2, epididymal sperm were cryopreserved in either Triladyl^® or Andromed^®. The mean (±SD) estimated number of sperm recovered was 468 ± 207 × 10⁶. There was an increase (p < 0.05) in the proportion of sperm with normal morphology between initial recovery and after extension (52.4 ± 4.6 vs 69.7 ± 2.4%), with a concurrent decrease (p < 0.05) in the proportion of sperm with distal droplets. Median values for progressively motile sperm in post-thaw samples (60%) were lower (p < 0.05) than that after extension or after chilling (70% for both). The mean percentages of viable sperm and of sperm with an intact acrosome were lower (p < 0.05) for frozen-thawed samples (38.7 ± 2.8 and 85.2 ± 1.1) compared with extended (66.2 ± 2.2 and 92.4 ± 0.9) or chilled (63.7 ± 2.5 and 90.0 ± 1.0) samples. Rates of cleavage, morulae and blastocyst production were not significantly different for chilled (70.9, 38.7 and 8.0%) vs post-thaw sperm (73.0, 46.0 and 6.3%). There was no significant difference between extenders for most sperm characteristics. In conclusion, we developed a functional protocol for the recovery and cryopreservation of epididymal sperm from plains bison, which may have implications for the genetic preservation of wood bison.     

D-lactate-induced neurotoxicity in calves

D-lactic acidosis occurs as a complication of short-bowel syndrome in humans and in a variety of other gastrointestinal disorders in monogastrics and ruminants. It is associated with signs of impaired central nervous system (CNS) function including ataxia and coma. The objective of this experiment was to determine if either acidification of nervous tissue or D-lactic acid is responsible for decreased neurological function. Eight Holstein calves (32 ± 11 d) were surgically catheterized with indwelling intravenous jugular and atlanto-occipital space cerebrospinal fluid (CSF) catheters and infused for 6 h in random order with iso-molar DL-lactic acid (DL-LA), L-lactic acid (L-LA), hydrochloric acid (HCl) or saline. DL-LA induced ataxia after 4 h of infusion and produced the greatest obtunding of CNS function (at 7 h, score 8.0 ± 0.4), whereas, the other infusions caused neither ataxia nor scores over 1.5 (p < 0.01 from DL-LA). After 6 h, DL-LA induced significantly less acidemia than HCl (pH 7.13 ± 0.06 and 7.00 ± 0.04, base excess −16 ± 1 and −23 ± 3 mmol/l, bicarbonate 11 ± 1 and 8 ± 1 mmol/L respectively, all p < 0.01), but greater than L-LA and saline (p < 0.01). CSF changes followed a similar but less pronounced pattern. Although HCl infusion produced a severe acidemia and CSF acidosis, only minor effects on neurological function were evident suggesting that D-lactate has a direct neurotoxic effect that is independent of acidosis. Conversely, L-LA produced only minor neurological changes.     

OC4Influence of Seminal Plasma Added to Highly Diluted Semen on Sperm Motility of Young Boar Feed with Selenium and Vitamin E

High dilution rates have been documented as detrimental for boar spermatozoa, shortening their lifespan (Centurion et al. 2003, Biol Reprod 69: 640–646). Addition of seminal plasma (SP) to semen extenders, or selenium (Se) and vitamin E (VE) in diet of boars could increase motility of highly diluted spermatozoa (HDS). The aim of this work was to evaluate the effect of seminal plasma on sperm motility of HDS from boars feed with Se and VE. Sixteen 12 month-old boars were designed to one of four dietary treatments: (i) control, Se 0 ppm–VE 0 IU/kg; (ii) Se 0–VE 250; (iii) Se 0.5–VE 250 and (iv) Se 0.5–VE 0. Boars were treated for 8 weeks before semen collection. Sperm rich fractions from each boar were diluted to 5 × 10⁶ sperm/ml in PBS medium and incubated at 37°C with or without 10% SP. The measurements were done at 0, 2 or 5 h. Data were analyzed as a mixed model for a factorial design [2 (Se) × 2 (VE) × 2 (SP) × 3 (h)]. Percentage of sperm motility (PSM) increases significantly (p < 0.001) with addition of Se (81.3 ± 1.52), VE (81.0 ± 1.62) and SP (81.5 ± 1.57) vs control (73.4 ± 1.61). There was significant interaction Se × VE (p < 0.001) and Se × VE × SP (p < 0.05) in PSM. However, PSM was affected significantly by time (0 h 83.4 ± 1.92; 2 h 80.7 ± 1.92 and 5 h 67.9 ± 1.92; p < 0.001). There was significant interaction SP × Time (p < 0.05) in PSM. These results indicate that Se, VE and SP improve seminal viability. Addition of 10% of SP maintains PSM at least during 5 hours.     

Isolation and Culture of Ovine and Bubaline Small and Large Pre-antral Follicles: Effect of Cyclicity and Presence of a Dominant Follicle

Studies were conducted to examine the effects of the cyclicity and the presence of a dominant follicle (DF) in ovary on the recovery and in vitro growth of pre-antral follicles (PFs) in sheep and buffalo. Small pre-antral follicles (SPFs, 100–250 μm) and large pre-antral follicles (LPFs, 250–450 μm) were isolated from slaughterhouse ovaries in the breeding seasons by a mechanical and enzymatic method. The sheep and buffalo PFs were cultured in vitro for 6 and 15 days, respectively, and examined for their growth, survival and antrum formation rates and growth rates of oocytes in cultured pre-antral follicles. The follicles of the sheep and buffalo were recovered and cultured simultaneously within replicates. The recovery rates (number per ovary) of both SPFs and LPFs were significantly (p < 0.05) higher in cyclic ewes (SPFs: 22.0 ± 3.3 vs 12.1 ± 2.6 and LPFs: 16.0 ± 3.6 vs 9.2 ± 1.8) and buffaloes (SPFs: 9.2 ± 1.3 vs 4.1 ± 1.0 and LPFs: 10.3 ± 2.7 vs 5.4 ± 0.7) compared with those recovered from acyclic ones. Presence of a DF in ovary significantly (p < 0.05) reduced the recovery rates of LPFs in ewes (9.06 ± 2.7 vs 16.4 ± 3.8) but had no effect in buffalo. Cyclicity of animals or follicular dominance had no effects on in vitro growth, survival and antrum formation rates and growth rates of oocytes in cultured PFs of SPFs and LPFs in both sheep and buffalo. The in vitro growth, survival and antrum formation rates of LPFs and growth rates of oocytes in cultured LPFs were significantly (p < 0.05) higher than those observed in SPFs in both sheep and buffalo. The overall recovery and growth rates of the PFs were lower in buffaloes compared with ewes.     

OC8Effect of Progesterone Supplementation During Early Foetal Period in Neospora caninum Seropositive Dairy Cows

The aim of this study was to analyse the effect of filtration through Sephadex on the subpopulation characteristics of the boar semen. For this purpose 3 ml of 16 commercial doses of fresh diluted boar semen were filtered through a Sephadex G-15/Polypropylene column. Motility parameters were analysed by a CASA system and statistical study was performed by SAS package using the VARCLUS and the FASTLUST procedures. Statistical study revealed four subpopulations in fresh boar semen, as previously had described (Theriogenology 61: 673–690).Total motility was higher in control than in filtered semen, but there were not statistical differences (65.63 ± 9.65 vs 41.40 ± 9.02). Moreover, the analysis did not show many changes neither in the characteristics nor in the distribution of the four subpopulations. As example although ALHmed of filtered samples were slightly higher, there were only significant differences (p < 0.001) in two subpopulations (subpopulation 2 : 2.2 ± 0.05 in control vs 2.7 ± 0.08 in filtered. Subpopulation 3 : 4.5 ± 0.11 in control vs 5.8 ± 0.23 in filtered semen). HME was also statistically different (p < 0.005) in one subpopulation, showing great values in filtered semen (1.7 ± 0.15 vs 3.0 ± 0.30). In conclusion, the filtration by Sephadex/Polypropylene column does not cause strong changes in subpopulation sperm distribution.     

Comparison of Two Doses of the GnRH Antagonist, Acyline, for Pregnancy Termination in Bitches

Gonadotropin-releasing hormone (GnRH) antagonists are particularly useful when a rapid inhibitory effect on the gonadal axis is required. The aim of this study was to test the efficacy and clinical safety of a low and high dose of the third generation GnRH antagonist, acyline, on pregnancy termination in female dogs. The effect of the antagonist on the progesterone (P₄) serum concentration was also described. Twenty-one mid-pregnant bitches were randomly assigned to a single subcutaneous (SC) dose of a placebo (PLACE; n = 7), a low (ACY-L; 110 μg/kg; n = 6) or high (ACY-H; 330 μg/kg; n = 8) dose of acyline. The animals were followed up for 15 days. All ACY treated but no placebo-treated animals terminated their pregnancy by abortion (p < 0.01). The ACY-L and ACY-H groups interrupted their pregnancy 7 ± 1.9 and 6.4 ± 1.3   days after treatment, respectively (p = 0.7). A significant interaction between treatment and day was found (p < 0.01) for P₄ serum concentrations when PLACE was compared with both ACY groups. No difference was found for this hormone between both ACY groups (p > 0.05) where P₄ diminished throughout the study. The decreasing rate varied among animals and was closely related to the time of abortion when P₄ reached basal concentrations. In PLACE animals, gestation progressed normally and P₄ did not change throughout the study (p > 0.05). None of the bitches presented side effects. It was concluded that acyline safely terminated mid-pregnancy by permanently decreasing P₄ serum concentrations.     

Field Trial on Progesterone Cycles, Metabolic Profiles, Body Condition Score and their Relation to Fertility in Estonian Holstein Dairy Cows

Resumption of luteal activity postpartum and fertility were investigated in an Estonian Holstein high milk production and good fertility dairy herd. Body condition was scored after every 10 days in 54 multiparous dairy cows (71 lactations) calving inside from December to March during 4-year period. Blood samples were taken 1–14 days before calving and 1–14, 28–42 and 63–77 days after calving: analytes estimated were serum aspartate aminotransferase (AST), glucose, ketone bodies, total cholesterol, non-esterified fatty acids and triglycerides. The general linear mixed model was used to compare the data for cows with different characteristics in luteal activity postpartum based on their milk progesterone profiles. Forty-five per cent of cases had abnormal profiles; delayed resumption of ovarian cyclicity postpartum (DC) was the most prevalent abnormality. There was no difference in body condition scores between the groups. The DC and prolonged luteal phase groups had higher serum AST activity (p < 0.01) 1–14 days postpartum compared with normal group. The DC group also had higher cholesterol and triglyceride values (p < 0.05) 28–42 days postpartum and higher milk fat/protein ratio (p < 0.01) on the first month of lactation compared with normal profile group. Despite long post-calving anoestrous period (71 ± 5.0 days; mean ± SEM) DC group had 64.7% first service pregnancy rate (normal group 48.6% and PLP group 37.5%). This study did not find any detrimental effect of prolonged anovulatory period postpartum on subsequent fertility.     

Comparison of the Effect of the Aromatase Inhibitor, Anastrazole, to the Antioestrogen, Tamoxifen Citrate, on Canine Prostate and Semen

This study compared the efficiency of the aromatase inhibitor, anastrazole, with the antioestrogenic receptor blocker, tamoxifen, on normal (NRL) and hyperplastic prostate glands. Forty healthy dogs were classified as NRL (n = 18) or abnormal (ABN) with benign prostate hyperplasia (n = 22). The dogs were randomly assigned to one of the following six groups, treated for 60 days; oral placebo for normal (NRL-PLC; n = 6) and abnormal (ABN-PLC; n = 6), oral anastrazole 0.25–1 mg/day, for normal (NRL-ANZ, n = 6) and abnormal (ABN-ANZ, n = 8) and oral tamoxifen citrate 2.5–10 mg/day for normal (NRL-TMX; n = 6) and abnormal (ABN-TMX; n = 8) dogs. The dogs were evaluated before treatment and then monthly for 4 months. At the end of the treatment, the prostatic volume decreased by 28.5 ± 4.3%, 21.6 ± 6.3% and 0.7 ± 1.0% in the ABN-TMX, ABN-ANZ and ABN-PLC (p < 0.01), respectively. From then on, prostatic volume began to increase without reaching pre-treatment values at the end of the study. In the ABN animals, there were no differences for this parameter between ANZ and TMX treatment (p > 0.1), whereas in the NRL animals ANZ produced a less pronounced decrease (p < 0.05), libido, testicular consistency and scrotal diameter decreased during treatment in the TMX group (p > 0.05). These parameters and sperm volume, count, motility and morphological abnormalities remained unaltered throughout the study in the ANZ and PLC groups (p > 0.05). There were no haematological nor biochemical side effects. Anastrazole might offer a safe and effective alternative for the medical management of dogs with benign prostatic hyperplasia.     

Hypertriglyceridaemic insulin-resistant obese dog model: effects of high-fat diet depending on age

In humans, obesity is closely associated with insulin resistance (IR) and dyslipidaemia. The purpose of this study was to explore the effect of age on metabolic disturbances related to obesity in dogs ( n  = 25). Three age-groups of dogs (puppies, young adults and mature adults) were overfed to induce obesity, and body composition, insulin sensitivity index (I_IS) (euglycaemic–hyperinsulinaemic glucose clamp) and plasma lipids were measured. Fat mass was similar in the three obese groups (30 ± 1% in puppies, 34 ± 1% in young adults and 39 ± 1% in mature adults). In mature adults, body weight (BW) increased (+45%, p < 0.001) and I_IS decreased (−60%, p < 0.001) over 22 weeks. In young adults, BW gain was similar but slower (60 weeks) and I_IS decreased to a lesser extent (−49%, p < 0.001). Overfed puppies weighed 30% more (p < 0.01) than normally-fed control puppies, but there was no change in I_IS. Unlike young and mature adults, obese puppies did not exhibit significant changes in triglycerides (TG) and free fatty acid concentrations. In conclusion, as in humans, obese dogs develop IR that is associated with high TG levels; however, younger animals may be better able to balance energy needs with energy consumption.     

Seasonal Profiles of Ovarian Activity in Iberian lynx (Lynx pardinus) Based on Urinary Hormone Metabolite Analyses

The Iberian Lynx Ex-Situ Conservation Programme is an essential part of a co-ordinated action plan to conserve the most endangered felid species of the world. Successful captive breeding demands reliable methods for reproduction monitoring including reliable non-invasive pregnancy diagnosis. During a 3-year study, urine samples from six captive Iberian lynx females were obtained (one non-pregnant, one pseudo-pregnant and 11 pregnant cycles). Progesterone, pregnanediol and oestradiol were determined in urinary extracts and relevant urinary oestrogen metabolites were characterized by high-performance liquid chromatography (HPLC). Urinary progestins did not follow the typical pregnancy-related course of felids. In the lynx, we failed to demonstrate an urinary progestin elevation during pregnancy. In contrast, urinary oestrogens increased from 3.8 ± 0.6 to 8.6 ± 0.5 ng/mg creatinine (p < 0.001) during the pregnancy. A comparison of pseudo-pregnant with pregnant cycles revealed a further increase of oestrogens caused by implantation (p < 0.05). In one female, which refused to mate, no difference was estimated between oestrogens levels during the breeding and non-breeding seasons. Almost 10-fold higher oestrogen concentrations were measured in urines of females that shared enclosures with males. HPLC analysis of oestrogens in urine samples collected from Iberian lynx during the pregnancy revealed that lynx urine is composed of two polar oestrogen metabolites in addition to oestrone and minor amounts of oestradiol. Oestrone was detectable in all urinary extracts (8–12% of metabolites), whereas oestradiol was elevated only during late pregnancy (18%). Thus, seasonal luteal activity in Iberian lynx can be monitored by urinary oestrogens. The increase of urinary oestradiol during late pregnancy might indicate an oestradiol secretion by the lynx placenta.     

Body Size and Testicular Traits of Tropically–adapted Bucks Raised Under Extensive Husbandry in Ethiopia

Contents Five tropically adapted buck breeds extensively managed in Ethiopia were studied to determine possible effects of breed and age on body size and testicular traits. In all, 177 bucks were selected following stratified random sampling, and evaluated in three age groups: <14 months (young), 14–19.5 months (intermediate) and 19.6–24 months (old). The breeds studied were Arsi-Bale (AB; N = 35), Central Highlands (CH; N = 33), Afar (N = 35), Boran (N = 36) and Woito-Guji (WG; N = 38). In all the three age groups, Boran and CH bucks were the heaviest (p < 0.05), Afar were the lightest, and AB and WG were in between. The highest body weight (BW) was achieved in the intermediate age group for Afar, but in the oldest age group for the other breeds. In the youngest age group, scrotal circumference (SC) was the widest (p < 0.05) for Boran and CH and the narrowest for Afar, AB and WG, while in the intermediate and the oldest age groups, Boran showed the widest SC. Boran, WG and CH had higher (p < 0.05) testicular weight (TW) than Afar and AB in the youngest age group. Boran retained the highest (p < 0.05) TW in the intermediate and the oldest age groups, while in the oldest age group WG and AB medium TW and Afar had the lowest TW. However, Afar had the highest TW expressed as percentage of BW. SC was well correlated with TW (p < 0.001; r  = 0.74) and BW (p < 0.001; r  = 0.61), indicating a linear, positive association between BW and TW (p < 0.001; r  = 0.51). In conclusion, body size and testicular traits of Ethiopian bucks under an extensive management system are influenced differently by breed and age group.     

Reproductive Performance of Gilts with Similar Age but with Different Growth Rate at the Onset of Puberty Stimulation

The aim of this study was to evaluate the reproductive performance of gilts that had a similar age but different weights at the onset of puberty stimulation by boar exposure at 144 days. Gilts were divided into two groups according to their lifetime growth rate from birth to approximately 144 days of age. Mean growth rates at this moment were 577 and 724 g/day for group 1 (G1; n = 58) and group 2 (G2; n = 58), respectively. After selection, gilts were weighed at approximately 155, 165 and 175 days of age, on the insemination day and at slaughter. Gilts were inseminated, on average, at 193 days of age and were slaughtered 32 days after insemination, when the number of corpora lutea and embryos were recorded. Higher growth rate gilts (G2) reached puberty earlier (155.3 vs 164.1 days; p < 0.01). More gilts of G2 group attained puberty by 190 days of age (p = 0.004) than G1 gilts (95%; 55/58 vs 76%; 44/58). The anoestrous rate, until 60 days after the onset of boar exposure was higher (p < 0.01) in G1 (19.0%; 11/58) than in G2 (3.4%; 2/58) group. However, there were no differences in the pregnancy rate (90.7 vs 94.5), ovulation rate (15.9 vs 16.5), total embryos (12.9 vs 11.7), viable embryos (12.0 vs 11.1) and embryo survival (73.7% vs 68.5%), between G1 gilts and G2 gilts, respectively (p > 0.05). High growth rate gilts attain puberty earlier and have a lower anoestrous rate than low growth rate gilts.     

Plasma Hormone Levels and Semen Quality in Male Cats during Non-Breeding and Breeding Seasons

Female cats are known to be seasonal breeders and male cats annual breeders. Despite this, there are limited data on the influence of breeding season (BS) on hormone concentration and semen quality in the male cat. This study compared plasma concentrations of LH and testosterone (T), and semen quality during the non-breeding season (NBS) and BS in five male cats subject to natural hours of daylight but a constant environmental temperature. Plasma LH and T concentrations were higher during the BS in 2/35 and 3/5 cats, respectively, although when comparing both hormones combined, values were higher during the BS than the NBS in all cats (p < 0.01). There were no significant differences in the percentage of abnormal sperm between the cats. Overall, semen quality was superior during the BS with larger semen volume in 2/5, sperm motility in 2/5 and sperm viability in 3/5 cats. Although there was a clear seasonal effect on hormone secretion and semen quality, during the NBS all cats were likely to have been fertile.     

Feed Intake and Sperm Morphology in Ogaden Bucks Supplemented with Either Agro-industrial By-products or Khat (Catha edulis) Leftover

In this study, feed intake and sperm morphology were evaluated in Ogaden bucks supplemented with either agro-industrial by-products or khat leftover. Thirty-five bucks at about 1 year of age, and 15 ± 1.5 kg initial body weight, were involved in a 12-week feeding programme that had four diet groups. The control (C) diet comprised grass hay alone, fed ad libitum ; treatment 1 (T1) comprised grass hay ad libitum supplemented with a mix of agro-industrial by-products at 1% of body weight (BW); treatment 2 (T2) comprised grass hay ad libitum supplemented with khat leftovers at 1% of BW; and treatment 3 (T3) comprised khat leftover alone, fed ad libitum . Bucks in T1–T3 consumed the highest (p < 0.001) dry matter (DM), crude protein (CP), organic matter (OM) and gross energy (GE) compared with control. Among the treatment groups, DM, OM and GE intakes were higher (p < 0.05) in T3 and T2, while CP intake was highest (p < 0.05) in T1. T1 and T3 improved (p < 0.001) the percentage of morphologically-normal spermatozoa in comparison with C, with bucks in T3 being best. The proportion of total abnormal sperm head shapes and proximal cytoplasmic droplets was lowest (p < 0.01) in T1 and T3 and highest in C. Although feeding with T1 improved feed intake and sperm morphology, feeding with T3 showed the highest response. Thus, we conclude that T3 and T1 could be utilized as feedstuff to improve sperm morphology in goats under the smallholder farming system in Ethiopia.     

Expression of MHC-I and -II in Uterine Tissue from Early Pregnant Bitches

The aim of the study was to investigate the expression of major histocompatibility complex (MHC)-I and -II in uterine tissues from pregnant and non-pregnant bitches, taken at different time periods after mating. The pregnant bitches were ovariohysterectomized during the pre-implantation (group 1, n = 4), implantation (group 2, n = 7) and placentation stage (group 3, n = 7). Non-pregnant animals in diestrus served as controls (group 4, n = 7). The expression of MHC- I and -II in salpinx, apex, middle horn, corpus uteri and at implantation sites was investigated by immunohistochemistry as well as qualitative and quantitative RT-PCR; MHC-I mRNA was detected in all tissues and with quantitative RT-PCR, and no significant changes were detected until placentation. Immunohistologically, at the apex and corpus site, the average number of MHC-II positive cells increased from the pre-implantation to the post-implantation stage (apex: 1.54 ± 1.21 to 3.82 ± 2.93; corpus: 1.62 ± 1.9 to 5.04 ± 4.95; p < 0.05). The greatest numbers of MHC-II positive cells were observed at placentation sites (6.64 ± 5.9). In parallel, a marked increase in the relative mRNA expression of MHC-II in uterine tissues was assessed from the pre-implantation to the placentation stage (relative to Glycerinaldehyd-3-phosphate-Dehydrogenase (GAPDH): 6.9 ± 9.5, 8.4 ± 5.8, p > 0.05). Immunohistologically, in the salpinx, significantly greater numbers of MHC-II positive cells were found in the tissues of pregnant animals than in the control group (p < 0.05). It is proposed that the increase in MHC-II is pregnancy-related, even though the impact on maintenance of canine pregnancy is still unclear.     

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.