Mahabadi Goat Research Articles

Impact of corn silage substitution for dry alfalfa on milk fatty acid profile, nitrogen utilization, plasma biochemical markers, rumen fermentation, and antioxidant capacity in Mahabadi lactating goats

This study aimed to investigate the effects of substituting conventional dry forage with corn silage, a more cost-effective supplementary feed, on a variety of parameters in lactating Mahabadi goats, native to arid and semi-arid regions. A total of fifty lactating Mahabadi goats, aged between 2 and 5 years and weighing an average of 45.3 ± 7.20 kg, were randomly allocated into two experimental groups. The experimental treatments consisted of a control diet and a diet incorporating corn silage at 20 % of dry matter (DM). Various measurements were conducted to assess milk compositions, fatty acid profiles, rumen fermentation parameters, selected plasma biochemical parameters, nitrogen balance, and antioxidant capacity. The results revealed that the substitution of dry forage with corn silage had no statistically significant impact on milk yield, dry matter intake (DMI), body weight, as well as the proportions of monounsaturated and unsaturated fatty acids, and specifically C18:1C9 in milk, non-esterified fatty acid content in milk, rumen concentration of volatile fatty acids (VFA), microbial nitrogen, and nitrogen balance (p > 0.05). Nonetheless, this substitution led to a reduction in the percentage of milk polyunsaturated fatty acids and plasma urea nitrogen content (p < 0.05). It is noteworthy that goats fed with corn silage exhibited a notably higher antioxidant capacity in rumen liquor (p < 0.05), plasma, and milk (p < 0.01) compared to those receiving the control diet. The substitution of conventional dry forage with corn silage exhibited no adverse effects on the performance of lactating Mahabadi goats. On the contrary, it contributed to an enhancement in the antioxidant status. These findings offer valuable insights for optimizing dietary composition by incorporating corn silage at 20 % of DM, thereby improving milk quality, reducing costs, and promoting overall health in lactating goats, particularly within arid and semi-arid regions.

Encapsulation of soybean meal and barley grain with calcium soap of sunflower fatty acids: Effects on growth performance and carcass characteristics in Mahabadi kids

Twenty-four Mahabadi goat kids with age of 3–4 months and initial body weight of 18.5 ± 0.5 kg were used to investigate the encapsulated soybean meal and barley grain with calcium soap of sunflower oil in a completely randomized design. Encapsulation of soybean meal and barley grain were evaluated on goat kids’ performance, carcass characteristics, and nutrient digestibility and blood metabolites. Before running the in vivo experiment, the ruminal degradability and intestinal digestibility of protected products were tested using in vitro and in situ techniques to prove the effectiveness of fat coating. For in vivo experiment, goat kids were fed by four dietary treatments for 104 days with 2 weeks in the beginning as adaptation and covariate period and 90 days as an experimental period. Treatments were basal diet (Control), a basal diet contained 40 g/kg of encapsulated barley grain (PB), a basal diet contained 40 g/kg of encapsulated soybean meal (PS), and a basal diet contained 40 g/kg of encapsulated barely grain plus 40 g/kg of encapsulated soybean meal (PB+PS). Encapsulation of barley grain and soybean meal with fat significantly reduced (P < 0.01) their ruminal degradability and increased (P < 0.01) their post-ruminal digestibility, however, there was no significant difference in total tract digestibility of protected products compared to control. Inclusion of these bypass products in goat kids' diet didn’t result in any significant difference in performance and carcass characteristics of goat kids. The results of the current study demonstrated that the coating of carbohydrate and protein sources by Ca-soap of sunflower fatty acids can be used as an effective approach to reducing rumen degradability without any significant deleterious effect on their intestinal and total tract digestibility, performance and carcass characteristics.

The Effect of essential oil from Carum copticum L on feed intake and metabolic response of Mahabadi goats in early lactation period

این آزمایش به­منظور بررسی اثرات افزودن اسانس زنیان بر گوارش­پذیری مواد مغذی و برخی فراسنجه‌های خونی و شکمبه­ای، تولید شیر و ترکیبات شیر در بزهای مهابادی انجام شد. تیمارهای آزمایش شامل جیره‌ی شاهد (جیره‌ی پایه ­ بدون اسانس زنیان)، جیره‌ی پایه +300 میلی‌گرم/ کیلوگرم ماده خشک اسانس زنیان و جیره‌ی پایه +600 میلی‌گرم/کیلوگرم ماده خشک اسانس زنیان بود. آزمایش بر اساس طرح مربع لاتین تکرارشده 3×3 و به صورت چرخشی با 3 تیمار و 3 دوره آزمایشی بر روی 6 رأس بز اجرا گردید. افزودن اسانس زنیان، تأثیری بر مصرف ماده خشک، قابلیت هضم، فرآسنجه­های شکمبه­ای (اسید استیک، اسید پروپیونیک+ ایزوبوتیریک، اسید والریک، اسید ایزووالریک، اسید بوتیریک، پروتزآ و pH) و فرآسنجه­های خونی (گلوکوز و پروتئین کل) نداشت (05/0>p) ولی در مقابل کل اسیدهای چرب، میزان کلسترول، تری‌گلیسرید و LDL در برابر تیمار شاهد کاهش یافته و HDL، کراتینین و اوره‌ی خون نیز افزایش نشان داد (05/0>p). به­طور کلی نتایج حاصل از این پژوهش نشان داد که افزودن اسانس زنیان به جیره­ی بزهای شیرده مهابادی، تاثیر معنی­داری بر عملکرد، تولید و ترکیب شیر نداشت. ولی باعث کاهش غلظت سرمی کلسترول، تری‌گلیسرید و LDLشد هرچند نیازمند تحقیقات بیشتر در این زمینه می­باشد

The effect of adding pyridoxine to soybean lecithin-based extender on goat semen quality parameters after the freeze-thawing process.

Supplementing the semen extender with various antioxidants can increase the quality of semen. The aim of the present study was to investigate the addition of pyridoxine (vitamin B6), a phenolic compound with antioxidant properties, to soybean lecithin extender on motility and quality indices of goat sperm after freezing-thawing process. Semen was collected at weekly intervals from four Mahabadi goats, mixed, and was divided into 7 subsamples. They were then diluted with the basal extender supplemented with 0, 2, 4, 6, 8, 10, and 12 mM pyridoxine. Following freeze-thawing process, quality parameters such as sperm motility characteristics, viability, plasma membrane integrity, and malondialdehyde content were determined. The results showed that pyridoxine at the level of 6 mM caused the highest total motility rate (P<0.05). Progressive sperm motility was highest at the 4, 6, and 8 mM pyridoxine (P<0.05). Although the control group showed the least progressive motility, it was not statistically significantly different from the 12 mM level. Among the pyridoxine levels, the 6 mM level recorded the best performance in term of plasma membrane integrity, sperm viability, and decreasing malondialdehyde concentration compared to the control group (P<0.05). The findings indicated that soybean lecithin extender supplemented with 6 mM pyridoxine can improve motility and quality parameters such as viability, plasma membrane integrity, and reduce oxidative stress of goat sperm after thawing.

Effects of dietary olive leaves on performance, carcass traits, meat stability and antioxidant status of fattening Mahabadi male kids

Twenty-four Mahabadi goat kids (5–6 months of age) were used to evaluate the effects of feeding olive leaves (OL) on performance, carcass traits and antioxidant status. The kids received three dietary treatments for 84 d with three levels of OL: 0 (control), 7.5 (OL7.5) and 15 (OL15) % (DM basis). Supplementation with OL had no effects on kid performance (P > 0.05). Total antioxidant capacity (TAC) was increased and malondialdehyde (MDA) concentration was decreased in plasma blood (P < 0.01) and Longissimus lumborum (LL) muscle (days 1, 4, 7 and 10) of kids (P < 0.01) with increasing level of OL in diet. The activity of glutathione peroxidase (GSH-Px) in LL muscle was increased (P < 0.05) in OL15 fed kids compared with control group. Also, glucose content of serum was decreased by adding OL to kid diets (P < 0.01). Finally, inclusion of OL to kid diets resulted in similar growth performance compared to alfalfa feeding, and improved the antioxidative potential of LL muscle.

Effects of Omega-3 fatty acid supplement and feeding frequency on insulin sensitivity and carcass characteristics in Mahabadi goat kids

This study was conducted to investigate the potential effects of different fat sources including fish oil (FO; n-3 fatty acids source) and palm oil (PO; C16:0 source) in combination with different feeding frequency (FF) on performance, glucose metabolism and carcass characteristics of Mahabadi goat kids. Twenty eight Mahabadi goat kids were used in a factorial design with 4 treatments including 2 types of fat supplement (calcium salt of FO versus PO) and 2 F F (2 or 4 times a day). The experiment lasted for 90 days. Daily dry matter intake was recorded throughout the experiment and body weight was measured every 21 days. The glucose tolerance test was conducted in day 70 of the experiment on 5 randomly selected goat kids from each treatments. The goat kids were slaughtered at the end of period for measurement of carcass characteristics. Inclusion of FO in diet alongside with feeding frequency of 2 caused a significant enhancement in visceral fat content (P < 0.05). Supplementation of FO in the diet (P < 0.01) and increasing the FF (P < 0.05) significantly increased glucose clearance rate. The results of the current study demonstrate that FO supplementation with FF of 4 times a day can enhance insulin sensitivity and the enhancement in FF can be used to prevent fat accumulation in visceral adipose depots as a consequence of higher insulin sensitivity caused FO supplementation.

Estimating the distance of genetic domestic goats in Iran inferred from D-loop region of mitochondrial DNA analysis and origins of candidate native goat ancestor

The wild goat “bezoar”(Capra aegagrus) has been considered to be the strongest candidate for the ancestor of the domestic goats (C. hircus) . This article describes the complete sequences of the mitochondrial DNA displacement loop (D-loop) region from Mahabadi goats. The control region (D-loop) is the most variable and non-coding portion of the mitochondrial genome.The genetic diversity and phylogenetic structure was analyzed in Mahabadi goat population by mitochondrial DNA sequences. It is estimated genetic distance between native goat and goat ancestor based on mtDNA. Recent analysis of the most of domestic goat individuals revealed a total of six different monophyletic mitochondrial DNA (mtDNA) haplogroups A, B, C, D, F, and G, with the A haplogroup representing >90% of individuals . Phylogenetic analysis was carried out using hyper variable region 1 (896 bp) obtained form 30 animals. All Mahabadi haplotypes were classified into A haplotype group and revealed remarkably high genetic distances within the population when compared with other goat populations from several places, indicating high genetic variation in the Mahabadi goat. After extracting DNA, displacement loop (D-loop) region of mtDNA was amplified with specific primers using PCR and after purification was sequenced. The phylogenic tree was drawn with the consensus sequence of other similar sequences of different goats breeds and wild goat “bezoar”(Capra aegagrus) obtained from GenBank. InThe phylogenic tree, Mahabadi native goat was clustered with Switzerland, Romania, Austria, Cyprus, Jordan, Spain, Saudi Arabia, Albania , Turkey, Egypt, Kurdi Iran, Malaysia, Kyrgyzstan, Italya and ancestor of native goat breeds. The findings confirmed that Mahabadi goats was closed to Capra aegagrus compared to other domestic goats.

Effects of vanadium supplementation on performance, some plasma metabolites and glucose metabolism in Mahabadi goat kids.

This experiment was conducted to investigate the effects of vanadium (V) supplementation on performance, some plasma metabolites (cholesterol and triglycerides) and glucose metabolism in Mahabadi goat kids. Twenty-eight male kids (15±2kg body weight) were fed for 14weeks in a completely randomized design with four treatments. Treatments were supplemented with 0 (control), 1, 2, and 3mg V as vanadyl sulfate/animal/daily. On day 70, an intravenous glucose tolerance test (IVGTT) was conducted. Dry matter intake did not change by V supplementation, but adding V quadraticaly improved feed efficiency (p=.03) and tended to increase average daily gain (Quadratic, p=.09). Blood metabolites were unaffected by V supplementation, except for concentration of glucose in plasma, which decreased linearly as supplemental V level increased (p=.02). Plasma glucose concentrations at 15, 30, 45 and 60min after glucose infusion were decreased in a quadratic fashion in response to increasing supplemental V level (p<.01). The IVGTT indicated that the kids supplemented with 2mg V had higher glucose clearance rate (K) and lower glucose half-life (T½ ; p<.05). Glucose area under the response curve from 0 to 60min and 0 to 180min after glucose infusion were decreased linearly (p=.04) by supplemental V. The results suggested that moderate supplementation of V may improve glucose utilization and feed efficiency in fattening kids.

Influence of Different Concentrations of Butylated Hydroxy Anisole on Quantity and Quality Parameters of Mahabadi goat Semen Following the Freeze–Thaw Process

Influence of Different Concentrations of Butylated Hydroxy Anisole on Quantity and Quality Parameters of Mahabadi goat Semen Following the Freeze–Thaw Process

Antioxidant status of dairy goats fed diets containing pomegranate seed oil or linseed oil

Twenty-four Mahabadi goats (DIM=45±6 d, BW=38.4±3.8kg, average daily milk yield=1.05±0.14kg) were used in a completely randomized design experiment for 42days to evaluate the effects of pomegranate seed oil and linseed oil on their performance, blood metabolites and antioxidant status. Experimental diets were: 1- control diet (basal diet without added oil, COND), 2- basal diet with 25g/kg DM pomegranate seed oil (PSOD) and 3- basal diet with 25g/kg DM linseed oil (LSOD). Dry matter intake (DMI), milk yield, milk protein, milk lactose, ADG and production efficiency in dietary treatments were similar in different groups (P>0.05), but milk fat increased by addition of linseed and pomegranate seed oils to diet (P<0.05). Blood metabolites (glucose, total cholesterol, triglyceride, LDH and LDL) were not affected by dietary treatments (P>0.05). Relative to the COND, PSOD increased total antioxidant capacity (TAC), whereas LSOD decreased TAC of milk and blood (P<0.05). In contrast, compared with the COND, milk and blood malondialdehyde (MDA) content decreased in goats fed PSOD, whereas LSOD increased MDA content of milk and plasma (P<0.001). Also, milk somatic cell count decreased with PSOD compared with COND and LSOD (P=0.001). The highest level of milk total polyphenols was found in goats fed PSOD (P<0.0001). Results suggest that it is possible to improve antioxidant status and milk fat of dairy goats by feeding pomegranate seed oil (25g/kg DM) as a natural antioxidants.

Antioxidant effect of quercetin in an extender containing DMA or glycerol on freezing capacity of goat semen

This study was performed to evaluate the effectiveness of quercetin as a non-enzymatic antioxidant in combination with glycerol or Dimethylacetamide (DMA), on freezability of goat semen. Ejaculates from four healthy mature Mahabadi goats were collected using an artificial vagina. After primary processing, semen was pooled and extended by egg yolk based extender supplemented with different concentrations of quercetin (10 or 20 μM) along with 5% glycerol or DMA. The extended semen was frozen and sperm motility parameters, viability, abnormality, membrane integrity and lipid peroxidation were assessed after thawing. Results showed that sperm viability, total motility, progressive motility, straightness (STR) and linearity (LIN) were higher (P < 0.05), and abnormality percentage and MDA concentration were lower (P < 0.05) in extender containing DMA. Similarly, higher (P < 0.05) total motility, progressive motility, viability and membrane integrity along with lower (P < 0.05) MDA level were noted in Q10 group. The lowest (P < 0.05) MDA level was observed in DMA extender containing moderate level of quercetin (Q10D). Also the STR was higher (P < 0.05) in Q10D compared to Q10G and Q20G groups. In conclusion, supplementation of extender with 10 μM quercetin in combination with DMA improves the goat sperm motion kinetics and suppresses lipid peroxidation after freezing and thawing. Furthermore, DMA is more effective cryoprotectant for the freezing of goat sperm.

Effect of pomegranate seed oil as a source of conjugated linolenic acid on performance and milk fatty acid profile of dairy goats

The objective of this experiment was to investigate the effects of dietary pomegranate seed oil and linseed oil on lactational performance, ruminal fermentation parameters, nutrients digestibility and milk fatty acid (FA) content, particularly conjugated linoleic acid (CLA), conjugated linolenic acid (CLnA) and vaccenic acid (VA) of dairy goats. Twenty-four Mahabadi goats in mid lactation were assigned to three dietary treatments: 1- control diet, basal diet without added oil (CON), 2- diet supplemented with 25g/kg pomegranate seed oil (PSO), and 3- diet supplemented with 25g/kg linseed oil (LSO), on a dry matter (DM) basis. Feed intake, milk yield and 4% fat-corrected milk yield were similar for goats fed different diets. Milk fat concentration (P<0.01) and fat/ protein ratio (P<0.0001) of goats fed PSO and LSO diets increased, while milk protein, lactose and solid not fat concentrations were not affected by diets (P>0.05). Addition of vegetable oils to diet had no effect on apparent digestibility of nutrients and ruminal fermentation parameters (P>0.05). The proportions of VA (P<0.001) and C18:1 (trans-9+trans-10, P<0.01) acids were increased in milk fat from goats fed PSO and LSO diets compared with goats fed CON diet. The concentration of cis-9, trans-11 CLA (rumenic acid) increased with oil supplements (P<0.0001) and was greatest for goats fed PSO diet. Compared with CON and LSO diets, feeding PSO diet increased cis-9, trans-11, cis-13 C18:3 CLnA (punicic acid) in milk fat (P<0.0001). The concentrations of monounsaturated fatty acids (MUFA; P<0.05), polyunsaturated fatty acids (PUFA; P<0.0001) and n-3PUFA (P<0.0001) increased and n-6/n-3 PUFA ratio (P<0.0001) decreased with oil supplemented diets. In conclusion, feeding PSO and LSO to dairy goats was a useful way to increase milk fat, CLA, and VA content of milk and to reduce the n-6/n-3 PUFA ratio without negative effects on intake, milk yield, and nutrients digestibility.

Identification of novel SNP in caprine β-lactoglobulin gene

β-lactoglobulin (β-LG) gene is suggested as a functional candidate gene for milk yield and milk composition. β-LG polymorphism has been reported to be associated with milk yield in cows, sheep and Indian goats. This study was performed to identify SNPs in exon 7 of β-LG gene and their association with milk traits in Iranian local Mahabadi goats using polymerase chain reaction (PCR)-single-strand conformation polymorphism (SSCP) and PCR-sequencing. Three SSCP patterns were observed with frequencies 0.678, 0.096 and 0.226, respectively. Subsequently, after sequencing each unique pattern nine novel mutations were identified. These mutations include: T InDel at nucleotide position 93 and substitutions T/C, T/G, T/C, G/T, T/G,T/C, G/A and A/T at nucleotide positions 99, 124, 126, 134, 147, 156, 176 and 177, respectively. Of these, seven mutations were same among the genotypic patterns while differences were related to T deletion and insertion (-/T) at nucleotide position 93 with frequencies 0.22 and 0.78 in the presence and absence of T allele, respectively; and substitution (A/T) at nucleotide position 177 with frequencies 0.16 and 0.84 for A and T alleles, respectively. Milk traits including milk production (gr), milk fat and protein (%) were also measured. These findings demonstrated that β-LG gene had a significant effect on milk protein percentage (P < 0.05), but had no significant effect on milk production and milk fat percentage.

Pomegranate seed pulp as a novel replacement of dietary cereal grains for kids

The objective of this experiment was to investigate the effect of partial replacing of cereal grains of diet with pomegranate seed pulp (PSP) on performance, nutrient digestibility and antioxidant capacity of fattening Mahabadi goat kids. Thirty-two Mahabadi male goat kids, 4–5 months of age and 16.5±2.8kg body weight (BW) were assigned to four dietary treatments: (1) diet without PSP (control), (2) diet containing 5% of PSP (PSP5), (3) diet containing 10% of PSP (PSP10), and (4) diet containing 15% of PSP (PSP15) (DM basis). The kids were slaughtered after 84d of feeding trial and antioxidant capacity was measured in the liver and longissimus lumborum (LL) muscle samples. Dry matter intake (DMI), average daily gain (ADG), and feed conversion ratio (FCR) were not affected by diets (P>0.05). Feed cost per kg of hot and cold carcass weight decreased with increasing levels of PSP in diet (P<0.05). Addition of PSP to diet decreased kidney fat (P<0.05) and tended to increase ether extract (EE) apparent digestibility (P=0.07). The LL muscle (P<0.05), liver (P=0.08) and plasma (P<0.05) samples from kids fed PSP15 displayed a greater antioxidant capacity than kids fed control diet. No significant difference was found in glutathione peroxidase (GSH-Px) activity among the groups (P>0.05), but the malondialdehyde (MDA) content of the LL muscle, liver and plasma decreased (P<0.05) in PSP15 group when compared with control group. The results of this study indicated that partial replacing of dietary cereal grains with PSP did not affect growth performance, carcass traits and nutrient digestibility, while decreased cost of meat production and improved the antioxidant capacity of kids.

Effects of Cr Methionine on Glucose Metabolism, Plasma Metabolites, Meat Lipid Peroxidation, and Tissue Chromium in Mahabadi Goat Kids

This study was designed to investigate the effects of chromium methionine (Cr-Met) on glucose metabolism, blood metabolites, meat lipid peroxidation, and tissue chromium (Cr) in Mahabadi goat kids. Thirty-two male kids (16.5 ± 2.8 kg BW, 4-5 months of age) were fed for 90 days in a completely randomized design with four treatments. Treatments were supplemented with 0 (control), 0.5, 1, and 1.5 mg Cr as Cr-Met/animal/daily. Blood samples were collected via heparin tubes from the jugular vein on 0, 21, 42, 63, and 90 days of experiment. On day 70, an intravenous glucose tolerance test (IVGTT) was conducted. At the end of the feeding trial, the kids were slaughtered, and the liver, kidney, and longissimus dorsi (LD) muscle samples were collected. Plasma glucose, insulin, and triglyceride concentrations were decreased by Cr supplementation (P < 0.05). LD muscle malondialdehyde (MDA) decreased, and plasma and tissue Cr contents increased with increasing supplemental Cr levels (P < 0.05). Plasma glucose concentrations at 30 and 60 min after glucose infusion were lower in the kids fed 1.5 mg Cr diet than the kids fed control diet (P < 0.05). The IVGTT indicated that the kids supplemented with 1.5 mg Cr had higher glucose clearance rate (K) and lower glucose half-life (T½; P < 0.05). Glucose area under the response curve (AUC) from 0 to 180 min after glucose infusion was decreased linearly (P < 0.01) by supplemental Cr. The results suggested that supplemental Cr may improve glucose utilization and lipid oxidation of meat in fattening kid.

Effects of various concentrations of BSA on microscopic and oxidative parameters of Mahabadi goat semen following the freeze–thaw process

Artificial insemination has an important role in goat breeding. Semen cryopreservation could provide genetic material from a small number of superior sires to a large number of females. The purpose of the present study was to investigate the effects of bovine serum albumin (BSA) on sperm parameters following the freeze–thaw process. Semen samples diluted with Tris-based extender containing various concentrations of BSA (0, 2.5, 5, 10, 15 and 20mg/mL), aspirated into 0.25mL straws, and equilibrated at 5°C for 2h. After equilibration, the straws were frozen in liquid nitrogen vapor and plunged into liquid nitrogen for storage. Frozen straws were thawed individually for 30s in a water bath (37°C) for microscopic evaluation. Sperm parameters in terms of motility and progressive motility, viability, membrane integrity, acrosome integrity and capacitation status, were assessed. Malondialdehyde (MDA) and glutathione peroxidase (GSH-PX) activity were also evaluated after freeze–thaw process. Freezing extenders supplemented with 10 or 15mg/mL of BSA had higher sperm motility, progressive motility and viability (p<0.05) following the freeze–thaw process. In biochemical assays, the application of 10 or 15mg/mL of BSA produced the lowest level of MDA, compared to the control group (p<0.01). It is concluded that inclusion of 10 or 15mg/mL BSA are beneficial additives for freezing Mahabadi goat spermatozoa in Tris–egg yolk diluent.

Effect of glutathione in soybean lecithin-based semen extender on goat semen quality after freeze-thawing

This study was conducted to investigate the effect of glutathione in a soybean lecithin-based semen extender on post-thawed goat semen quality. A total of 20 ejaculates were collected from four Mahabadi goats and diluted with four extenders: (1) egg yolk tris-based extender (EYT), (2) soybean lecithin-based extender (SL0), (3) soybean lecithin-based extender containing 5mM glutathione (SL5), and (4) soybean lecithin-based extender containing 10mM glutathione (SL10) and the experiment was replicated for five times. Sperm motility and motion parameters, the percent of normal sperm, plasma membrane integrity, viability, and the levels of malondialdehyde (MDA) were determined after freeze-thawing. Glutathione at the level of 10mM provided the lowest percent of total and progressively motile sperm (45±2.94, 25.8±1.81). The percent of plasma membrane intact sperm was lower in SL5 (55.44±2.4) and SL10 (51.52±2.4) than that of EYT (64.27±2.4) and SL0 (62.93±2.4). Sperm viability was significantly decreased in SL10 (57.98±2.27) in comparison with EYT (66.89±2.27). The percent of normal sperm was not significantly different between groups. Also, the MDA level was lower in SL5 (1.61±0.29) than that of other groups. The results of this study showed that most of the post-thawed sperm quality parameters were not significantly different between EYT and SL0. Moreover, addition of 5 and 10mM glutathione in a soybean lecithin-based extender could not improve goat sperm quality after freeze-thawing. In conclusion, it seems that soybean lecithin-based extender can be a suitable replacement for egg yolk tris-based extender, but addition of glutathione at 5 and 10mM cannot fortify the soybean lecithin-based extender for goat semen cryopreservation.

Effects of different concentrations of BHT on microscopic and oxidative parameters of Mahabadi goat semen following the freeze–thaw process

Oxidative damage to sperm is one of the main causes for decline in motility and fertility of frozen–thawed sperm. Thus, it is crucial to use cryoprotectant agents in extender in order to prevent lethal intracellular ice crystal formation. The present study aims to evaluate the effects of different concentrations of the antioxidant butylated hyroxytoluene (BHT) on sperm parameters post-thaw. Semen was diluted into five equal aliquots of extender containing different concentrations of BHT (0, 0.5, 1, 2 and 4mM), aspirated into 0.25mL straws, and equilibrated at 5°C for 2h. After equilibration, straws were frozen in liquid nitrogen vapor and plunged into liquid nitrogen for storage. Sperm parameters, including motility and progressive motility, viability, membrane integrity, acrosome integrity and capacitation status, were assessed. Malondialdehiyde (MDA) and glutathione peroxidase (GSH-PX) activity were also evaluated after freezing-thawing. Results of this experiment show that addition of 1mM of BHT to the extender for freezing of goat semen can improve motility, progressive motility and viability (P<0.05) and reduce the MDA level (P<0.01). HOST (hypo-osmotic swelling test), acrosome integrity, capacitation status and GSH-PX were not affected by the concentrations of BHT (P>0.05). Therefore, we conclude that the optimum concentration of BHT for cryopreservation of goat semen is 1mM.

Performance, carcass traits, muscle fatty acid composition and meat sensory properties of male Mahabadi goat kids fed palm oil, soybean oil or fish oil

This study examined the effect of palm, soybean or fish oils on the performance, muscle fatty acid composition and meat quality of goat kids. Twenty-four male Mahabadi kids (BW=19.4±1.2kg) were divided into three groups according to liveweight and randomly allocated to one of three diets. Animals were fed ad libitum for 84days. Different dietary fat sources had no effect on performance and/or carcass quality attributes. The soybean oil diet decreased 16:0 and 18:0 concentrations and increased 18:2 and 18:3 and the ratio of PUFA/SFA in the muscle compared with other treatments. Fish oil feeding increased 20:5 n-3 and 22:6 n-3 concentrations and decreased the ratio of n-6/n-3 in the muscle. The results demonstrate that the use of fish oil is a nutritional strategy to improve the health claimable long-chain omega-3 fatty acid content and n-6/n-3 ratio in goat meat without changing the sensory properties or colour of meat.

We-P12:278 Estrogen replacement therapy decreases RLP concentration in plasma: Oral and transdermal ERT comparison

The objective of this experiment was to investigate the effects of dietary pomegranate seed oil and linseed oil on lactational performance, ruminal fermentation parameters, nutrients digestibility and milk fatty acid (FA) content, particularly conjugated linoleic acid (CLA), conjugated linolenic acid (CLnA) and vaccenic acid (VA) of dairy goats. Twenty-four Mahabadi goats in mid lactation were assigned to three dietary treatments: 1- control diet, basal diet without added oil (CON), 2- diet supplemented with 25 g/kg pomegranate seed oil (PSO), and 3- diet supplemented with 25 g/kg linseed oil (LSO), on a dry matter (DM) basis. Feed intake, milk yield and 4% fat-corrected milk yield were similar for goats fed different diets. Milk fat concentration (P<0.01) and fat/ protein ratio (P<0.0001) of goats fed PSO and LSO diets increased, while milk protein, lactose and solid not fat concentrations were not affected by diets (P>0.05). Addition of vegetable oils to diet had no effect on apparent digestibility of nutrients and ruminal fermentation parameters (P>0.05). The proportions of VA (P<0.001) and C18:1 (trans-9+trans-10, P<0.01) acids were increased in milk fat from goats fed PSO and LSO diets compared with goats fed CON diet. The concentration of cis-9, trans-11 CLA (rumenic acid) increased with oil supplements (P<0.0001) and was greatest for goats fed PSO diet. Compared with CON and LSO diets, feeding PSO diet increased cis-9, trans-11, cis-13 C18:3 CLnA (punicic acid) in milk fat (P<0.0001). The concentrations of monounsaturated fatty acids (MUFA; P<0.05), polyunsaturated fatty acids (PUFA; P<0.0001) and n-3PUFA (P<0.0001) increased and n-6/n-3 PUFA ratio (P<0.0001) decreased with oil supplemented diets. In conclusion, feeding PSO and LSO to dairy goats was a useful way to increase milk fat, CLA, and VA content of milk and to reduce the n-6/n-3 PUFA ratio without negative effects on intake, milk yield, and nutrients digestibility.