Assessment of feeding varying levels of Metabolizable energy and protein on performance of transition Murrah buffaloes

Fifteen close up pregnant Murrah buffaloes of mean body weight (668.3 ± 24.03) kg, lactation number (2.8 ± 0.17) and expected producing ability (EPA) (2125.7 ± 46.34) were randomly distributed into three groups each of five animals to investigate the performance at different levels of metabolizable energy and protein. Control group was fed as per ICAR Nutrient requirements of animals (2013) recommendation whereas treatment group (1) high metabolizable energy and high metabolizable protein (HMEMP) and group (2) low metabolizable energy and low metabolizable protein (LMEMP) were offered with ration containing 15% more and 15% less ME and MP, respectively. The feeding trial was carried out for the period of 40 days before parturition and continued for 120 days after parturition. Intake of dry matter (DM) (%BW) was similar among experimental groups. Metabolizable energy (ME) (MJ/100 kg BW) and metabolizable protein (MP) (g/100 kg BW) intake was highest in HMEMP followed by control and LMEMP group, respectively. Digestibility trial of 7 days was conducted at 60 days post-partum and it was observed that apparent digestibility coefficients (%) of DM, organic matter (OM), crude protein (CP), ether extracts (EE), neutral detergent fiber (NDF) and acid detergent fiber (ADF) were similar among the experimental groups. Milk yield (kg/kg DMI) was similar among treatment groups whereas 6% fat corrected milk (FCM) was lower in LMEMP group as compared to HMEMP and control. No significant effect of dietary MP and ME levels on milk composition was observed among experimental groups. There were no significant difference in non esterified fatty acid (NEFA), blood urea nitrogen(BUN), growth hormone (GH) and insulin like growth factor-1(IGF-1) concentration among different experimental groups whereas concentration of immunoglobulin G (IgG) (μg/ml) was found to be lower in LMEMP. The study results indicate that nutrient digestibility and lactation performance was not affected with 15% variation in intakes of ME and MP in lactating Murrah buffaloes.     

PCR-SSCP analysis of leptin gene and its association with milk production traits in river buffalo (Bubalus bubalis)

Leptin gene has been found to be associated with various economic traits including milk production and fat quality in dairy animals. In the present study, we investigated genetic variations in intron 1 region of leptin gene in riverine buffaloes (Bubalus bubalis) using polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and sequencing methods and associated them with milk traits. The study revealed three SSCP variants A, B and C among a total of 301 buffaloes from nine breeds. The frequency of variant C was found invariably high among all the breeds except in Marathwada buffalo. Variant A was found to be absent in Chilika, Nili-Ravi, Nagpuri and Pandharpuri breeds and also had the lowest frequencies in Mehsana, Jaffarabadi, Murrah and Toda breeds. Sequencing of SSCP variants revealed a total of five polymorphic sites, with three haplotypes. Statistical analysis revealed significantly high fat percentage at 150?days in SSCP variant B in Mehsana buffaloes. However, the associations of SSCP variants of leptin gene with total milk yield, 305?days milk yield and total fat yield were found to be non-significant. The present study is the first report on association analysis of leptin gene polymorphisms with milk production and milk quality traits in river buffalo.     

Nutritional evaluation of organically grown fodders in lactating Murrah buffaloes (Bubalus bubalis)

A study was undertaken to evaluate the nutritional response of organically grown diets in buffaloes on nutrients utilization and nutrient efficiency for milk production. For this, ten milch Murrah buffaloes of average body weight (490.72?±?6.65 kg), milk yield (8.13?±?0.33 kg), and lactation stage (85?±?5.28 days) were distributed in inorganic (InDg₎ and organic dietary groups (OrDg) with five animals in each. Buffaloes of InDg and OgDg were fed sorghum hay–berseem fodder-concentrate mixture-based diets grown inorganically and organically, respectively. After 60 days of feeding, a digestion cum metabolism trial was conducted to assess feed intake, nutrient utilization, and N balance, while milk yield and composition were recorded fortnightly. DM, CP, digestible crude protein (DCP), and metabolizable energy (ME) intake (g/Kg w^0.75) were similar in animals of InDg and OrDg. NDF, ADF, and hemicellulose digestibility were (P?<?0.05) higher in animals on OrDg (59.20, 51.55, and 62.67) than InDg diet (54.57, 43.72, and 56.61 %), respectively. Urinary n loss (g/day) was (P?<?0.05) lower in OrDg (67.23) than in InDg (83.55); however, milk N was comparable in animals of both dietary groups (47.36 vs 45.82 g/day). Nitrogen balance was higher in animals of OrDg (39.72) than in InDg (28.08). DCP, TDN, and ME values of both diets were similar. No effect of diet was observed on milk yield and its composition; however, increased lactation length decreased milk yield. Buffaloes on both diets had similar efficiency and conversion ratio of nutrients for milk production. Results revealed that diets (organically vs. inorganically grown) have no effect on milk yield and its composition; however, buffaloes on organic diet have higher fiber digestibility and low urinary N loss which did not affect the dietary nutrients efficiency and conversion ratio for milk production.     

Effect of rumen-protected nutrients on feed intake,body weights,milk yield,and composition in Murrah buffaloes during early lactation

The effect of rumen-protected nutrients (bypass fat, BPF; bypass protein, BPP; or their combination, BPPF) was investigated in Murrah buffaloes during the early stage of lactation. Forty Murrah buffaloes (BW 531.92?±?10.85 kg) just after parturition were randomly distributed into four groups according to parity and milk production. Buffaloes individually fed ration from day 0 to 90 postpartum according to feeding group and nutrient requirement. Control and BPF fed groups received a concentrate mixture, CM1 with 25% rumen-protected protein (using barley, wheat bran, and mustard oil cake), BPP and BPPF groups received a second concentrate mixture, CM2 with 40% rumen-protected protein (using barley, de-oiled rice bran, and cottonseed cake). Bypass fat fed groups (BPF and BPPF) additionally were supplemented with 15 g BPF (Ca salt of long-chain fatty acids) per kg milk yield in their respective concentrate mixtures. Dry matter intake, body weights, body condition score, and total milk yield were similar between groups (P?>?0.05). Fat-corrected milk (FCM) production was improved (14.5%, P?>?0.05) in groups fed BPP and BPPF, while significant (19.45%, P?<?0.05) improvement was observed in BPF-fed group. Overall mean values of milk fat, solid not fat, protein, lactose, and total solids were found to be high (P?<?0.05) in treatment groups as compared with control values. It may be concluded that supplementation with BPP or BPF either alone or in combination positively influences the quality of milk produced in Murrah buffaloes during early lactation and BPF additionally had improvement on the quantitative trait of milk as well.

     

Development of sustainable performance index based on production,reproduction, health and longevity for genetic improvement of Sahiwal cattle

An attempt was made for the first time in India to develop the performance indices for quantifying the relative emphasis to be given to production, reproduction, health and longevity traits for selection and genetic improvement of Sahiwal cattle in a sustainable manner. The study was conducted using information related to various production, reproduction, health and longevity traits spread over a period of 29 years in Sahiwal cattle. Using income and expenditure method, the relative economic values for 305 days milk yield (305DMY), average daily milk yield (ADMY), calving to first insemination interval (CFI), days open (DO) and longevity (LNG) were estimated as 1, 1, −6.62, −6.62 and 5.96 in Sahiwal cattle. A total of three performance indices were constructed using three-trait combination, that is production, reproduction and longevity before and after excluding the days suffered by the animals. Correlation between the aggregate genotype and index (R_IH) was computed to determine the accuracy of each performance index, and based on highest R_IH value, best performance index was identified for selection of Sahiwal cattle. Developed indices were further assessed for robustness by increasing the relative economic values of the traits by 25% and 50%. The performance index (305DMY, DO and LNG) was found to be the best index before as well as after excluding days suffered by the animals, but in later case emphasis to be given to different traits was found to be more balanced. The best index indicated that about 47, 42 and 11% relative emphasis to be assigned to 305 days milk yield, days open and longevity for selection of Sahiwal animals for sustainable genetic improvement.     

Milk yield and lactation length of Ghana Sanga and its crosses with the Friesian Raised under agropastoral system

Milk yield traits and lactation length of two breeds of cattle raised on natural pasture with little or no supplementation were assessed. A total of 42 573 daily milk records on 98 Friesian-Sanga cows collected over a period of 10 years and 17 790 daily milk records on 72 Sanga cows spanning a 6-year period were used in the study. Traits examined for each breed were daily milk yield, total milk yield, 305-day milk yield, 305-day milk yield/day and lactation length. Friesian-Sanga cows outperformed their Sanga counterparts in all traits studied. Friesian-Sanga cows had an average daily milk yield of 1.35?±?0.00 kg; average total milk yield of 266?±?12 kg; average 305-day milk yield of 339?±?10 kg; average 305-day milk yield/ day of 1.11?±?0.03 kg and mean lactation length of 201.1?±?6.9 days. Average values for Sanga cows were 1.01?±?0.00 kg as daily milk yield; 162?±?12 kg as total milk yield; 244?±?10 kg as 305-day milk yield; 0.80?±?0.03 kg as 305-day milk yield/day. Mean lactation length for Sanga cows was 164.1?±?9.4 days. Season of calving significantly (P?<?0.05) influenced daily milk yield of Friesian-Sanga cows and all traits of Sanga cows with animals calving in the major rainy season surpassing those that calved in the minor and dry seasons. Daily milk yield for both Friesian-Sanga and Sanga cows was significantly (P?<?0.05) influenced by season of lactation. Daily milk yield gradually declined from second parity towards the sixth parity for Friesian-Sanga cows. A gradual increase in daily milk yield from first to third parity was observed in Sanga cows. Year of calving significantly influenced all traits for both breeds. Genetic improvement in milk yield traits and lactation length is achievable for both breeds of cattle as co-efficient of variation of traits were moderate to high.     

Tuberculosis prevalence and risk factors for water buffalo in Pará, Brazil

The prevalence of and possible risk factors for tuberculosis were studied in water buffalo from Pará, Brazil. In this study, 3,917 pregnant and nonpregnant female Murrah and Mediterranean buffaloes were studied; 2,089 originated from Marajó Island, and 1,108 were from the mainland. The comparative cervical tuberculin test was used as a diagnostic test for tuberculosis in these animals. The prevalence of positive buffaloes was 3.5 % (100/2,809) on Marajó Island and 7.2 % (80/1,108) on the mainland. The municipalities with the highest tuberculosis prevalence rates in animals were Ipixuna do Pará (10.1 %), Marapanim (9.8 %), Chaves (9.4 %), Paragominas (8.6 %), and Cachoeira do Arari (6.7 %). The tuberculosis prevalence was not significantly different between the Murrah (4.3 %) and Mediterranean (4.8 %) breeds or between pregnant (5 %) and nonpregnant (4.3 %) buffaloes. Tuberculosis was detected in water buffaloes from Pará, Brazil; the mainland buffalo exhibited the highest tuberculosis prevalence. These results indicate that this disease is dangerous to public health and buffalo farming in Pará.     

Development of a predictive model for daughter pregnancy rate and standardization of voluntary waiting period in Murrah buffalo

A predictive model for daughter pregnancy rate (DPR) in Indian Murrah buffaloes has been developed. The data pertaining to first lactation reproduction traits, viz., age at first calving (AFC), first service period (FSP), and number of services per first conception (NS/FCON) of 719 Murrah buffaloes calved from 1985 to 2010 at the National Dairy Research Institute (NDRI), Karnal (Haryana), India were adjusted against significant environmental influence. First lactation reproduction records of 474 Murrah buffaloes were used for determining voluntary waiting period (VWP) and estimating DPR. Seven simple and multiple regression models in each case were developed where the buffaloes had their first insemination after 63 days (DPR 63), 84 days (DPR 84), and 105 days (DPR 105) of first calving. Among the seven models (I to VII) for DPR 63, DPR 84, and DPR 105, model II, having only FSP as an independent reproduction variable, was found to be the best prediction model, based on the four statistical criterions (high coefficient of determination (R ²), low mean sum of squares due to error (MSSe), conceptual predictive (CP) value, and Bayesian information criterion (BIC)). Three linear equations were developed using model II, viz., DPR 63?=?0.0033 (274???FSP), DPR 84?=?0.0027 (332???FSP), and DPR 105?=?0.0027 (310???FSP). The average errors for the prediction of DPR 63, DPR 84, and DPR 105 were 1, 13, and 8 %, respectively. Therefore, 63 days of VWP is the optimum period for getting the best DPR in Indian Murrah buffaloes.     

奶牛泌乳曲线数学模型的遗传分析

本文采用Wood、改进多项式、回归模型各参数估值及拟合、预报奶量进行了方差分析,遗传力、遗传相关估计及BLUP法育种值估计。方差分析结果表明,产犊季节和胎次对各性状具有较为显著的影响。各遗传相关的估值均较高,这是由环境因素及取样情况所致。实际及估计305天产奶量的遗传力估值较高,Wood模型参数c、改进多项式模型参数d及回归模型参数d、e的遗传力估值也相对较高。各估计、预报奶量及各选定模型参数的BLUP育种值排队序号与实际305天产奶量BLUP育种值排队序号均呈极显著的秩相关(p<0.001).这表明可以用估计和预报奶量及模型参数来评定种公牛的优劣。这对奶牛生产和育种实践具有一定的实践意义。     

广西的尼里—拉菲水牛和摩拉水牛mtDNA D-loop区遗传多样性研究

[目的]探究引入广西南宁的尼里-拉菲水牛和摩拉水牛的mtDNA D-loop区遗传多样性与母系起源。[方法]采用PCR扩增、测序及生物信息学方法。[结果]对从广西南宁采集的52个江河型水牛（尼里-拉菲水牛25个,摩拉水牛27个）mtDNA D-loop序列与GenBank下载的20条尼里-拉菲水牛和23条摩拉水牛序列进行联合分析,共检测到112个变异位点,定义42个单倍型,发现摩拉水牛（Hd: 0.934±0.027）与尼里-拉菲水牛的遗传多样性（Hd: 0.929±0.017）都很丰富。NJ系统发育树显示尼里-拉菲水牛和摩拉水牛含有江河型和沼泽型水牛mtDNA支系,表明尼里-拉菲水牛和摩拉水牛引入中国后均与沼泽型水牛进行了杂交,在外貌上很难区分。[结论]引入广西南宁的尼里-拉菲水牛和摩拉水牛与沼泽型水牛存在广泛的血缘混杂现象。     

Effect of bypass fat supplementation on productive performance and blood biochemical profile in lactating Murrah (Bubalus bubalis) buffaloes

The study investigated the effect of dietary supplementation of bypass fat on productive performance and blood biochemical profile of lactating Murrah buffaloes (Bubalus bubalis). Fifteen multiparous buffaloes (2-4 lactation) of early to mid lactation were divided in three homogenous groups T(1) (control), T(2), and T(3) of five each. The animals in T(1) were fed with a basal diet consisting of a concentrate mixture, green sorghum, and wheat straw as per requirements, while the animals in group T(2) and T(3) were fed with same ration supplemented with 0.7 % (100?g/day) and 1.4 % (200?g/day) bypass fat (on dry matter intake (DMI) basis), respectively. The feed intake, milk yield, and milk composition were not influenced by supplemental bypass fat. However, fat-corrected milk (6.5 %) yield was higher (P?相似文献   

热应激对摩拉和尼里-拉菲水牛血液生化指标的影响

【目的】 试验旨在探究热应激条件下摩拉和尼里-拉菲水牛的血液生化指标变化规律。【方法】 选取体况相近的健康摩拉和尼里-拉菲水牛各11头。试验期划分为热应激期和非应激期, 并于各试验期分别进行4次采血, 每次间隔1周。测定血清激素浓度、抗氧化指标和离子浓度等生化指标。【结果】 摩拉水牛热应激期血清超氧化物歧化酶(SOD)活性及总胆固醇(CHOL)、丙二醛(MDA)、热休克蛋白70(HSP70)、钾离子(K⁺)、钠离子(Na⁺)、氯离子(Cl^-)含量均显著高于非应激期(P<0.05), 谷丙转氨酶(ALT)、谷草转氨酶(AST)、谷胱甘肽过氧化物酶(GSH-Px)活性及总抗氧化能力(T-AOC)、胰岛素样生长因子1(IGF-1)、皮质醇(CORT)、瘦素(LEP)、钙离子(Ca²⁺)含量均显著低于非应激期(P<0.05);尼里-拉菲水牛热应激期血清白蛋白(ALB)、CHOL水平及谷氨酰基转移酶(GGT)活性均显著高于非应激期(P<0.05), 球蛋白(GLOB)含量显著低于非应激期(P<0.05)。在热应激期, 摩拉水牛ALT活性及总蛋白(TP)、GLOB、CHOL、尿素氮(BUN)、甘油三酯(TG)含量均显著高于尼里-拉菲水牛(P<0.05), ALB、四碘甲腺原氨酸(T₄)、K⁺含量均显著低于尼里-拉菲水牛(P<0.05);在非应激期, 摩拉水牛ALT活性、BUN、TG、葡萄糖(GLU)含量及T-AOC均显著高于尼里-拉菲水牛(P<0.05)。【结论】 热应激降低了摩拉和尼里-拉菲水牛的内分泌激素水平和抗氧化能力并影响了机体电解质平衡, 尼里-拉菲水牛的免疫功能也有一定下降; 在热应激条件下, 摩拉水牛表现出更强的清除自由基能力, 尼里-拉菲水牛表现出更好的代谢、体温调节能力以及电解质代偿能力。     

Relationship of temperament with oestrous behaviour,resumption of ovarian cyclicity and milk yield in post‐partum Murrah buffaloes

This study was designed to investigate the relationship of temperament with oestrus, resumption of ovarian cyclicity and milk yield in post‐partum buffaloes. For this study, 102 post‐partum Murrah buffaloes were observed for temperament in open paddock and during milking. Based on the temperament score (1–5 score), they were classified into docile, slightly restless, restless, aggressive and nervous. Oestrous behaviour was monitored twice daily in all the buffaloes along with milk yield (weekly), body weight (BW) and body condition score (BCS) at day 0, 30, 60 and 90 post‐partum. Based on the temperament score, the number of buffaloes classified as docile, slightly restless, restless and aggressive was 37 (36.27%), 28 (27.45%), 30 (29.41%) and 7 (6.86%), respectively, but none under nervous category. Number of buffaloes resuming cyclicity in various temperaments groups were as follows: docile (n = 35; 94.59%), slightly restless (n = 22; 78.57%), restless (n = 20; 66.67%) and aggressive (n = 7; 85.71%). Temperament was not correlated (p = .128; r=?.152) with oestrous behaviour. But, temperament was correlated (p < .0001; r = .384) with the resumption of cyclicity as docile and slightly restless buffaloes resumed cyclicity (p < .0016) earlier. Temperament of buffaloes was weakly correlated (p = .0017; r=?.306) with milk production with higher (p < .0358) total milk yield in docile (1022 ± 23.75 kg) and slightly restless buffaloes (948 ± 35.86 kg) as compared to other temperament groups. In summary, temperament of post‐partum buffaloes was related with resumption of ovarian cyclicity and milk yield, but not oestrous behaviour.     

Trends in the reproductive performance of Holstein dairy cows in Iran

The study was undertaken to determine the trends in the reproductive performance of Holstein dairy cows in Iran during 1994 to 2008. Reproductive performance data for 528,034 lactations of 246,132 cows in 1,822 Holstein dairy herds of Iran were used. The potential effect of calving season, herd, parity, calving year, as well as herd size and 305-day milk production on reproductive performance traits was investigated using multiple regression models. The least squares means of age at first calving decreased by 3.1 (±0.06) days per year from 806.5 (±96.3) days in 1994 to 788 (±89.9) days in 2008. The least squares means of calving interval increased 1.02 (±0.03) days per year from 394.1 (±65) days in 1994 to 413.2 (±81) days in 2008. Greater 305-day milk production was associated with an average increase of 6.55 (±0.08) days in calving interval per 1,000-kg increase in milk yield. Larger herd size was associated with an average decrease of 0.22 (±0.02) days in calving interval per 50 cows per herd. The mean number of days dry was 88.6 (±51.3) days and increased by 0.82 (±0.02) days per year. In conclusion, reproductive performance in Holstein dairy herds has generally decreased, whereas herd size and milk production have increased over time. Producers may make significant improvements in herd reproduction by reviewing management strategies including the sire selection, reproductive management, inseminator training and techniques, and improved estrous detection. Moreover, it may be advisable for the fertility traits to be included in the genetic selection indices to reduce the rate of reproductive decline.     

Studies on cisternal and alveolar fractions &; its composition and mammary health of Murrah buffaloes administered oxytocin

The study was conducted on 18 lactating Murrah buffaloes in 83.72 ± 14.75 days after calving. Group I buffaloes were not injected with oxytocin and served as control. Buffaloes of Group II were injected with oxytocin @ 2.5 IU per 0.5 ml intramuscularly at the hip region for a period of 1 month while Group III buffaloes received injection of oxytocin @ 5.0 IU per ml intramuscularly at the hip region for a period of 1 month. Milk samples from three groups of buffaloes were collected after oxytocin injections at 15 days interval on 0, 15, 30 and 45 days. Blood samples were collected in heparinized tubes at 0, 15, 30 and 45 days of experiment from all three groups of buffaloes. There was no significant change in cisternal, alveolar and total milk yield by exogenous oxytocin administration. Fat % in cisternal, alveolar and total milk decreased significantly (P < 0.01) by 11.8% and 21.3% in groups II and III buffaloes, respectively. Protein % increased significantly (P < 0.01) in group III. A significant increase was observed in somatic cell counts of milk by 5.36% and 6.22% in groups II and III, respectively as compared to control group. Part of MV. Sc. Thesis of the first author submitted to National Dairy Research Institute (Deemed University)     

Risks factors associated with subclinical mastitis in water buffaloes in Pakistan

The present study was carried to ascertain the association of various risk factors of mastitis in water buffaloes. The milk samples from buffaloes were collected and screened through California Mastitis Test for the presence of mastitis. In the present study, 15.2 % prevalence of subclinical mastitis was recorded both at the government (13.4 %) and private farms (15.5 %). The chi-square analysis showed significantly higher involvement of the right rear and front quarters. The analysis of variance technique showed significant difference in live body weight, milk yield, teat end to floor distance (P?<?0.001), udder depth, teat length, and teat diameter in mastitic and healthy buffaloes. The frequency analysis also revealed significant difference between various groups including lactation stage, teat and/or udder pathology, teat shape, and udder shape (P?<?0.001). The logistic regression analysis revealed significant positive association of mastitis with milk leakage, live body weight, milk yield, parity, calf suckling, pendulous udder, number of attendants at the farm, dirty hind legs, and udder depth.     

摩拉水牛及德宏水牛瘤胃产甲烷菌多样性比较

本试验旨在比较分析摩拉水牛及德宏水牛瘤胃液中产甲烷菌的多样性。选取健康雌性摩拉水牛及德宏水牛各3头,采用口腔导管法收集瘤胃液,酚-氯仿-异戊醇抽提法提取瘤胃液总DNA,用产甲烷菌特异性引物Met86F/Met1340R扩增产甲烷菌16S rDNA,构建16S rDNA基因克隆文库。摩拉水牛及德宏水牛各获得96个16S rDNA基因序列,均归类于Methanobacteriales目,其中德宏水牛有82个序列（18个OTUs）与已知菌的16S rDNA序列相似性≥ 97%,占总序列的85.4%,有14个序列（9个OTUs）与已知菌16S rDNA序列相似性为89%~97%;摩拉水牛有94个序列（13个OTUs）与已知菌16S rDNA序列相似性≥ 97%,占总序列的97.9%,仅有2个序列（1个OTUs）与已知菌16S rDNA序列相似性为94%。系统进化树分析表明,所有序列分别聚集于两大分支上,其中德宏水牛有13个OTUs代表序列和摩拉水牛7个OTUs代表序列聚集在进化树顶端的同一分支上,且在系统发育距离上与Methanobacteriales目中任何已知相似序列都相隔较远。德宏水牛瘤胃中的SGMT簇序列和RO簇序列所占总序列比列分别为83.3%、9.4%,摩拉水牛瘤胃中的SGMT簇序列和RO簇序列所占总序列的比列分别为51.0%、9.4%。由此可见,摩拉水牛及德宏水牛瘤胃产甲烷菌序列以Methanobacteriales目为主,其中德宏水牛拥有更多未知的产甲烷菌序列;德宏水牛瘤胃中的SGMT簇产甲烷菌序列比例要高于摩拉水牛。     

摩拉水牛和尼里-拉菲水牛PRKAA2基因SNPs检测及遗传多样性分析

为研究水牛蛋白激酶AMP活化的催化亚基α2（protein kinase AMP-activated catalytic subunit alpha 2,PRKAA2）基因多态性,本试验以摩拉水牛和尼里-拉菲水牛基因组DNA为模板,扩增PRKAA2基因外显子4及内含子3部分序列,通过常规测序法检测其SNP并进行遗传多样性分析。结果发现,PRKAA2基因外显子4内存在1个SNP位点（c.462 G>A）,PRKAA2基因内含子3部分序列存在3个SNPs位点（IVS3.557 T>C、IVS3.560 C>T和IVS3.565 G>A）。经遗传多样性分析表明,在c.462 G>A位点的野生纯合型和杂合型比突变纯合型更有优势,IVS3.557 T>C和IVS3.560 C>T位点的突变纯合型为非优势基因型,IVS3.565 G>A位点杂合型为优势基因型。IVS3.565 G>A位点在摩拉水牛群体中处于Hardy-Weinberg非平衡状态;c.462 G>A位点在尼里-拉菲水牛群体中处于Hardy-Weinberg非平衡状态。4个SNPs位点在摩拉水牛群体中均为中度多态;c.462 G>A、IVS3.557 T>C位点在尼里-拉菲水牛群体中为低度多态,IVS3.560 C>T、IVS3.565 G>A位点为中度多态。IVS3.557 T>C位点在两个水牛群体中杂合度较低。说明摩拉水牛IVS3.565 G>A位点和尼里-拉菲水牛c.462 G>A位点的基因型频率和基因频率遗传状态不平衡,尼里-拉菲水牛群体中IVS3.557 T>C位点遗传变异小,选择潜力不高。4个多态位点可以构建5种单倍型,其中T-C-G-G是摩拉水牛群体和尼里-拉菲水牛群体的优势单倍型。综上,本研究检测的摩拉水牛和尼里-拉菲水牛PRKAA2基因上4个SNPs位点可为水牛标记辅助选择育种提供参考。     

Efficacy of different methods for detecting the onset of ovarian cyclicity in post-partum Murrah buffaloes

This study was designed to investigate the sensitivity and specificity of three methods for detecting the onset of cyclicity in post-partum Murrah buffaloes. The methods investigated were visual signs, transrectal ultrasonography, and serum progesterone (P₄) assay. For this study, 102 post-partum Murrah buffalo cows were grouped for monitoring their ovarian activity. The first group of buffaloes was between 26 and 35 days post-partum. Thereafter, the buffalo cows that calved were grouped after every 10 days for the study sample. Thus, the study animals were adjudged between 26 and 35, 36–45, 46–55, 56–65, 66–75, 76–85, and 86–95 days post-partum with an average of 30, 40, 50, 60, 70, 80, and 90 days post-partum, respectively. Visual estrus signs were monitored twice daily, and simultaneously, ultrasound examination was carried out at 10 days interval for accessing the presence of corpus luteum (CL). Serum P₄ was estimated in the animals which were adjudged cyclic by ultrasound examination, and the assay was repeated after 10 days. The buffalo cows in estrus were inseminated artificially, and pregnancy status was assessed after 30 days post-insemination. In this study, the sensitivity and specificity of visual observation were low (39.37 and 70.73%, respectively) when compared to P₄ assay (98.80 and 96.47%) and ultrasound examination (single, 97.59 and 97.59%; double, 100 and 100%), respectively. Furthermore, the sensitivity and specificity of single and double ultrasound examination and P₄ assay were comparable. In conclusion, this study reports that single and double ultrasound examination and P₄ assay are more efficient than visual observation in detecting the onset of ovarian cyclicity in post-partum Murrah buffaloes.     

A review on breeding and genetic strategies in Iranian buffaloes (<Emphasis Type="Italic">Bubalus bubalis</Emphasis>)

The aim of current study was to review breeding progress and update information on genetic strategies in Iranian buffaloes. Iranian buffalo is one of the vital domestic animals throughout north, north-west, south and south-west of Iran with measurable characteristics both in milk and meat production. The species plays an important role in rural economy of the country due to its unique characteristics such as resistance to diseases and parasites, having long productive lifespan and showing higher capability of consuming low-quality forage. In Iran, total production of milk and meat devoted to buffaloes are 293,000 and 24,700 tons, respectively. Selection activities and milk yield recording are carrying out by the central government through the Animal Breeding Centre of Iran. The main breeding activities of Iranian buffaloes included the estimation of genetic parameters and genetic trends for performance traits using different models and methods, estimation of economic values and selection criteria and analysis of population structure. Incorporating different aspects of dairy buffalo management together with improved housing, nutrition, breeding and milking, is known to produce significant improvements in buffalo production. Therefore, identifying genetic potential of Iranian buffaloes, selection of superior breeds, improving nutritional management and reproduction and developing the education and increasing the skills of practical breeders can be useful in order to enhance the performance and profitability of Iranian buffaloes.