Does Vitamin E or Vitamin E plus Selenium improve reproductive performance of rams during hot weather

The objective of this study was to determine the effect of Vitamin E (Vit E) and Selenium (Se) on semen quality, sexual activity, packed cell volume (PCV), and white blood cell counts (WBC) of Awassi rams during the hot season. Twelve Awassi rams were subdivided into three groups and treated for 90 days. Rams in the 1st group (T1) were treated twice weekly with 175 mg/ram vitamin E at intervals of 12h; rams in the 2nd group (T2) were treated on the same schedule with 70 mg/ram vitamin E plus 2800 mg selenium; and rams in 3rd group (T3) served as controls. Sperm quality (percentage of motile cells and percentage of morphologically normal cells) and quantity (sperm volume, and concentration) were recorded weekly. Sexual activity was tested by using the pen libido test at monthly intervals. Blood samples were taken before treatment and after the 1st, 2nd, and 3rd months. Semen quality was significantly affected by treatments: the ejaculate volume increased in T2 vs T1, and T3; mass activity and individual motility were increased in T1 and T2 vs T3. Sperm concentration was increased in T2 and T1 vs T3, and the percentage of dead and abnormal spermatozoa was reduced in T1 and T2 vs T3, though the differences were not statistically significant. Pen libido test showed reduced reaction time for the first mount in the 1st month in T2 and T1 vs T3. The number of serves was increased in groups T1 and T2 vs T3. There were no significant differences in PCV among groups. After 3 months from the beginning of treatments, the percentage of lymphocytes increased in T1 and T2 vs. T3, while the percentage of neutrophils was reduced in T2 vs T3 in the 2nd and 3rd months. The results of this experiment indicate that treatments with vitamin E alone or in combination with selenium improved semen characteristics and reproductive performance of Awassi rams during the hot season

Effects of fibre and non-fibre carbohydrate and level of intake on microbial protein yield in Sarda sheep

Three studies using Sarda dairy sheep in dry, mid-lactation and late-lactation were carried out. Forty ewes for each physiological stage were fed 8 complete pelleted diets, which differed from each other in NDF and NFC content and source. Based on their main ingredient, diets were denominated: corn meal (CM), wheat middlings (WM), corn flakes (CF), barley meal (BM), corn cobs (CC), beet pulp (BP), alfalfa (AA), and soybean hulls (SH). In each study, rumen microbial protein (MCP) synthesis was estimated measuring urinary purine derivatives. In dry sheep, MCP synthesis was not affected by diet, while in mid- and late-lactation sheep dietary effects were observed. In mid-lactation, the highest MCP production was found for BM and BP (171 and 166 g/d, respectively), while the lowest was observed with AA (63 g/d). In late-lactation, the highest MCP yield (146 g/d) was observed in BP, while the lowest were for SH and CM. MCP synthesis, for each diet, was higher in mid-lactation than in latelactation, which in turn were higher than in the dry period. Dry matter intake (DMI) was positively associated to MCP. The MCP synthesis was best predicted by dietary energy (NEL) or digestible organic matter intake (dOMI)

Does Vitamin E or Vitamin E plus Selenium improve reproductive performance of rams during hot weather?

The objective of this study was to determine the effect of Vitamin E (Vit E) and Selenium (Se) on semen quality, sexual activity, packed cell volume (PCV), and white blood cell counts (WBC) of Awassi rams during the hot season. Twelve Awassi rams were subdivided into three groups and treated for 90 days. Rams in the 1st group (T1) were treated twice weekly with 175 mg/ram vitamin E at intervals of 12h; rams in the 2nd group (T2) were treated on the same schedule with 70 mg/ram vitamin E plus 2800 mg selenium; and rams in 3rd group (T3) served as controls. Sperm quality (percentage of motile cells and percentage of morphologically normal cells) and quantity (sperm volume, and concentration) were recorded weekly. Sexual activity was tested by using the pen libido test at monthly intervals. Blood samples were taken before treatment and after the 1st, 2nd, and 3rd months. Semen quality was significantly affected by treatments: the ejaculate volume increased in T2 vs T1, and T3; mass activity and individual motility were increased in T1 and T2 vs T3. Sperm concentration was increased in T2 and T1 vs T3, and the percentage of dead and abnormal spermatozoa was reduced in T1 and T2 vs T3, though the differences were not statistically significant. Pen libido test showed reduced reaction time for the first mount in the 1st month in T2 and T1 vs T3. The number of serves was increased in groups T1 and T2 vs T3. There were no significant differences in PCV among groups. After 3 months from the beginning of treatments, the percentage of lymphocytes increased in T1 and T2 vs. T3, while the percentage of neutrophils was reduced in T2 vs T3 in the 2nd and 3rd months. The results of this experiment indicate that treatments with vitamin E alone or in combination with selenium improved semen characteristics and reproductive performance of Awassi rams during the hot season

Effects of short-term feed restriction on milk yield and composition, and hormone and metabolite profiles in mid-lactation Sarda dairy sheep with different body condition score

Ten Sarda dairy ewes (5 with high Body Condition Score: H-BCS, BCS>2.5; BW 48.8±5.4 kg; 5 with low BCS: L-BCS, BCS<2.5; BW 36.2±4.7 kg) were subjected, after 7-day preliminary (Prel) period, to short-term feed restriction (FR, 50% of nutrient requirements) for three days followed by refeeding (Re-Fed, 100% requirements) for three days. Milk yield and composition (protein, fat, lactose, MUN, SCC, fatty acids), and blood parameters (glucose, NEFA, BUN, insulin, GH, IGF-I, leptin) were monitored. Milk yield decreased during FR in both BCS groups: at day 3 it was 38% and 35% of Prel values in HBCS and L-BCS ewes, respectively, reaching Prel levels at Re-Fed in both groups. Milk fat concentration was influenced by BCS¥sampling, increasing in H-BCS ewes during FR, but not varying in L-BCS ewes throughout the trial. During FR, milk protein increased as milk yield decreased. There was no change in milk urea nitrogen concentration during FR, but this decreased in both BCS groups during Re-Fed. FR modified the FA profile of milk fat in both BCS groups, increasing LCFA at the expense of SCFA and MCFA. Some blood parameters (NEFA, GH and IGF-I) were influenced by BCS, whereas almost all parameters were influenced by sampling. There was a rapid return to initial levels in all parameters except milk urea, blood urea and insulin at Re-Fed

Amélioration de la qualité de la semence des béliers de race <i>Awassi</i> d'Irak par l'utilisation de hCG = Increase of semen quality of Iraqi <i>Awassi</i> rams using the hCG hormone

La race Awassi en Irak représente environ 60 % de la population ovine locale. Cette race est bien adaptée aux conditions difficiles du climat du pays, caractérisé par un été long, sec et très chaud, pendant lequel les béliers ont une libido limitée et une mauvaise qualité de la semence. Plusieurs études ont mis en évidence des effets de la saison sur la qualité de la semence (volume de l’éjaculat, motilité et concentration spermatique) et la température élevée en été est souvent considérée comme une cause d’infertilité temporaire. Même si les béliers Awassi sont sexuellement actifs toute l’année, la libido et la qualité de la semence varient d’une saison à l’autre. La libido est généralement meilleure en hiver et au printemps et relativement faible en été, alors que la qualité de la semence est d’habitude meilleure entre avril et juin. Il semble que les fonctions testiculaires les plus influencées par la saison soient la stéroïdogenèse et la spermatogenèse. Le développement de systèmes de production intensifs d’agneaux lors de la dernière décade nécessite la disponibilité de béliers manifestant une activité sexuelle élevée et une bonne qualité de la semence tout au long de l’année

Effects of dietary NDF concentration on milk yield and composition in dairy goats in mid-late lactation

Fourteen Sarda goats in mid-late lactation were housed in individual pens where they received a common total mixed ration (TMR) during the preliminary period (21 d). During the experimental period (24 d) the goats were divided in two isoproductive groups and fed differentiated TMR: one group received a high NDF-low no fibre carbohydrate (NFC) total mixed ration (H-NDF diet = 44.7% NDF, 29.3% NFC, DM basis), while the other received a low NDF-high NFC total mixed ration (L-NDF diet = 36.9% NDF, 36.0% NFC, DM basis). These differences were achieved substituting ground corn and barley grains with beet pulp shreds and soybean hulls. Both diets contained 50% of dehydrated chopped alfalfa on a DM basis. Soybean meal completed the diets. Dry matter intake was higher in the H-NDF group, while dietary energy intake and body weight variations did not differ significantly between the two groups. Milk yield was significantly higher in the L-NDF group, while milk protein and milk urea were higher in the H-NDF group. Milk fat concentration and somatic cell count did not differ between groups, while milk fat and milk protein yields were higher in the L-NDF group. These results are in clear contrast to what was previously observed in sheep, fed diets similar to the ones used here, in which H-NDF diets induced higher milk yield than L-NDF ones

Replacing chicken yolk with yolks from other sources in ram semen diluents and their effects on fertility <i>in vitro</i>

Over the past 70 years, egg yolk (EY) has been continuously used as a cryoprotectant in semen diluents. Earlier studies have shown that the composition of different EYs showed that the basic components were present in similar levels. However, further breakdown and analysis revealed significant differences between EY sources. The objective of this study was to evaluate and compare the effect of substitution chicken EY in ram semen diluents with yolks from other species on in vitro fertilization, subsequent embryonic development and total blastocysts formation. Through the breeding season, ejaculates were collected weekly from five Sarda breed rams of proven fertility, divided equally and diluted in Tris–citrate–fructose–glycerol based diluents containing 20% (v/v) of either partridge, ostrich, turkey, duck, tortoise, or chicken EYs (as a control) at 37 °C. Extended semen was cooled to 4 °C and preserved as a 0.25 mL pellet in LN2. Adults Sarda ewe ovaries were collected from a local slaughterhouse and a total of 913 collected oocytes were divided randomly and matured oocytes were fertilized in vitro with frozen–thawed spermatozoa prepared as described above, and cultured until Day 8. The proportions of cleaved and expanded blastocysts/groups were evaluating after 46, and 144–192 h post-insemination (hpi), respectively. Among all sources of EYs, semen cryopreserved in presence of partridge EY significantly increased the proportion of fertilized matured oocytes compared with semen preserved in presence of tortoise or chicken EYs (105/131, 80.1%), (74/123, 60.2%), and (189/270, 70.0%), respectively. Interestingly, using partridge, ostrich, turkey, and duck EYs in ram semen diluents increased significantly (P &lt; 0.001) the number of blastocysts formation on Day 6 after IVF versus tortoise or chicken yolks. However, there was no significant difference in total blastocysts yield between all sources of EY. In conclusion, the different compositions of yolks did offer different levels of in vitro production embryos. Specifically, semen diluents in presence of partridge yolks improved cleavage rates, and the numbers of early embryonic development. Whereas using ostrich, turkey, and duck EYs offered comparable fertilization and embryonic development versus conventional semen diluents with 20% chicken EY

Pseudogestation et mortalité embryonnaire chez les chèvres Sarde et Saanen: étude préliminaire

Dans une communication précédente, nous avons rapporté les résultats d’une étude sur la pseudogestation (PG) chez la chèvre de race Sarde, qui se basait sur la concentration de PSPB (Pregnant Specific Protein B) mesurée 35 jours après la fin du traitement de synchronisation de l’oestrus et le diagnostic de gestation réalisé par échographie après 60 jours (Epifani et al., 2004). Toutefois, la chronologie des suivis et l’absence des données relatives à la progestérone plasmatique (P4) ne nous a pas permis de distinguer la PG de la mortalité embryonnaire (ME). Cette étude a eu pour objectif d’évaluer l’existence et l’incidence de la PG chez les chèvres élevées en Sardaigne, en la distinguant de la ME et de l’avortement (A)

The Effect of sperm preparation and brief gamete coincubation length on ovine oocytes fertilization, subsequent development and embryo quality

Over the past 70 years, egg yolk (EY) is frequently used as a cryoprotectant in semen diluents and has been confirmed highly effective for the maintenance of sperm fertility. However, the preparation of uniform diluents containing EY is hard. Since Cheng, (1985) reported the beneficial effect of overnight gamete oocytes coincubation length in IVF, this protocol was used a recommended protocol in several species. However, this protocol leading to exposure of oocytes and embryos to toxic effects associated with excessive generation of reactive oxygen species. The aims of this study were to examine (i) whether brief exposure of mature ewe oocytes to frozen-thawed semen prepared with different semi-defined diluents may affect fertilization, enhanced embryonic development, embryo quality before and/or after freezing vs. long coincubation length, and (ii) explore the accompanying effects of different semi-defined diluents and coincubation length on fertilization and embryo development rates

Effet des jours longs et de la mélatonine sur la réponse à l’effet mâle chez la chèvre Sarde = Effect of long days and melatonin on the response to male effect in Sarda goats

La chèvre Sarde montre une activité sexuelle saisonnière : les chaleurs apparaissent en été-automne et se terminent en hiver (Casu et al., 1981). La nécessité d’avoir les mises bas en automne oblige l’éleveur à avancer l’activité sexuelle des chèvres à juin. C’est pourquoi il est nécessaire induire des ovulations synchrones en dehors de la saison sexuelle. Normalement, ce but est atteint grâce à un traitement hormonal qui implique l’emploi d’acètate de fluorogestone (FGA), cloprostenol et gonadotrophine sérique de jument gravide (PMSG). Toutefois, ce traitement entraîne la production d’anticorps anti PMSG, avec une réduction progressive de son efficacité, et la présence de résidus hormonaux dans le lait, au-dessus des limites autorisées. Puisque la saison sexuelle est réglée par la photopériode et l’introduction des boucs dans un troupeau de chèvres en anoestrus induit l’activité ovulatoire, la manipulation de la photopériode et l’emploi de l’effet mâle sont deux facteurs non pharmacologiques capables d’induire et de synchroniser l’activité ovarienne des chèvres. Ce travail avait pour but d’étudier l’effet de jours longs (avec ou sans mélatonine) sur la réponse à l’effet mâle chez la chèvre Sarde, afin d’induire et synchroniser l’activité ovarienne en dehors de la saison sexuelle, avec une méthode douce et économiquement acceptable