Effect of feeding protected fat and proteins on milk production,composition and nutrient utilization in Murrah buffaloes (Bubalus bubalis)

Objective of this study was to investigate the effect of feeding protected fat and proteins on milk production, composition and nutrient utilization in Murrah buffaloes (Bubalus bubalis). Eighteen buffaloes were divided into two groups (9 each) on the basis of most probable production ability. Buffaloes in control group (C group; most probable production ability 2204 kg) were fed chaffed wheat straw, chopped maize fodder and concentrate mixture as per requirements. Buffaloes in supplemented group (S group; most probable production ability 2211 kg) were fed same ration as C group plus 2.5% rumen protected fat (on dry matter intake basis) and formaldehyde treated mustard and groundnut oil cake (1.2 g formaldehyde/100 g crude protein) in place of unprotected cakes. Group S buffaloes were supplemented rumen protected fat and protein 60 days pre-partum to 90 days postpartum and persistence of milk production was monitored up to 210 days of lactation. Milk yield during supplementation period (90 days) in S group was 13.11 kg/d and was 19% higher (P<0.01) than the C group (11.01 kg/d), whereas after supplement withdrawal (120 days), it was 11.04 kg/d and was 15% higher (P<0.01) than the C group (9.61 kg/d). There was no effect on total solid, protein, solid-not fat (SNF) and lactose contents in the two groups, whereas milk fat yield was increased (P<0.05) and level of milk urea nitrogen was decreased (P<0.01) in S group. Moreover, the supplement produced noticeable changes in the fatty acid profile of the milk fat, i.e., reduction in the concentration of saturated fatty acids (SFA) by 19% and an increase in that of unsaturated fatty acids (USFA) by 36%. Besides, digestibility of dry matter, crude protein, acid detergent fiber and neutral detergent fiber were not affected, whereas ether extract digestibility was higher (P<0.05) in S group. There was no effect on plasma glucose, non-esterified fatty acids, triglycerides and cholesterol concentrations between two groups, whereas blood urea nitrogen concentration was lower (P<0.01) in S group. Supplementation of protected nutrients to buffaloes increased milk production and unsaturated fatty acids content in milk fat and persistence of lactation after supplements were withdrawn.     

Dominance of Methanomicrobium phylotype in methanogen population present in Murrah buffaloes (Bubalus bubalis)

Aims:  To study the diversity of rumen methanogens in Murrah buffaloes ( Bubalus bubalis ) from North India by using 16S rRNA gene libraries obtained from the pooled rumen content from four animals and using suitable software analysis.
Methods and Results:  Genomic DNA was isolated and PCR was set up by using specific primers. Amplified product was cloned into a suitable vector and the positive clones were selected on the basis of blue–white screening and sequenced. The resulting nucleotide sequences were arranged in the phylogenetic tree. A total of 108 clones were examined, revealing 17 different 16S rRNA gene sequences or phylotypes. Of the 17 phylotypes, 15 (102 of 108 clones) belonged to the genus Methanomicrobium , indicating that the genus Methanomicrobium is the most dominant component of methanogen populations in Murrah buffaloes ( Bubalus bubalis ) from North India. The largest group of clones (102 clones) was more than 98% similar to Methanomicrobium mobile . BLAST analysis of the rumen contents from individual animals also revealed 17 different phylotypes with a range of 3–10 phylotypes per animal.
Conclusion:  Methanomicrobium phylotype is the most dominant phylotype of methanogens present in Murrah buffaloes ( Bubalus bubalis ).
Significance and Impact of the Study:  Effective strategies can be made to inhibit the growth of Methanomicrobium phylotype to reduce the methane emission from rumen contents and thus help in preventing global warming.     

Efficacy of the Ovsynch protocol for synchronization of ovulation and fixed-time artificial insemination in Murrah buffaloes (Bubalus bubalis)

Two experiments were conducted to assess the timing and synchrony of ovulation, plasma LH concentrations, and pregnancy rate in Murrah buffaloes (Bubalus bubalis) treated with the Ovsynch (GnRH-PGF(2 alpha)-GnRH) protocol. In Experiment 1, 10 non-lactating cycling buffaloes received 10 microg of a GnRH analogue i.m. (buserelin acetate) without regard to the stage of the estrous cycle (day of treatment, day 0), followed by 25mg of PGF(2 alpha) i.m. (dinoprost thromethamine) 7 days later. A second-treatment of the same GnRH analogue (10 microg, i.m.) was given 48 h after PGF(2 alpha). Ovulation was confirmed by transrectal palpation (at 2-h intervals) from the second-GnRH treatment to detection of ovulation or up to 96 h after the second-GnRH treatment. Plasma LH concentrations were determined in blood samples collected at 15-min intervals for 6h, starting at the second-GnRH treatment, and thereafter at 2-h intervals until 2h after detection of ovulation. Ovulation occurred in 9/10 buffalo (90%) 23.3+/-1.3h (mean+/-S.E.M.; range 20--32 h) after the second-GnRH treatment. Peak LH concentrations 13.5+/-3.5 ng/mL (range 3.9--40.0 ng/mL) occurred 2.1+/-0.1h (range 1.2-3.0 h) after the second-GnRH treatment. In Experiment 2, 15 lactating, cycling buffaloes were subjected to the Ovsynch protocol, with fixed-time AI 12 and 24h after the second-GnRH treatment and 75 lactating buffaloes were inseminated, approximately 12h after detection of spontaneous estrus. Pregnancy rates were 33.3% for TAI and were 30.7% for buffaloes inseminated following spontaneous estrus (P=0.84). In conclusion, the Ovsynch protocol effectively synchronized ovulation in Murrah buffaloes and resulted in conception rates (to two fixed-time inseminations) that were comparable to those achieved with a single AI after detection of spontaneous estrus.     

Serum FSH levels during estrus and a 4-week period following mating in Murrah buffaloes (Bubalus bubalis )

Circulating FSH levels of 13 Murrah buffaloes were investigated by a double-antibody radioimmunoassay using a homologous bovine system. The mean (+/- s.e.m.) peak FSH level on the day of estrus was if57.94 +/- 12.84 ng/ml of blood serum during hotter months (June-August) and 65.23+/-10.54 ng/ml during cooler months (October-December). These were much higher than the FSH concentrations recorded during the rest of the cycle post-mating. There were sizable fluctuations in FSH levels on different days of the estrous cycle within animals. However, the mean values did not exhibit much variation. The occurrence of the FSH peak and the LH peak coincided during the cycle.     

Repeated ultrasound-guided transvaginal oocyte retrieval from cyclic Murrah buffaloes (Bubalus bubalis): oocyte recovery and quality

The present study was undertaken to explore the potential of the Murrah breed of buffaloes as donors of oocytes and to find out the recovery rate and oocyte quality in cyclic Murrah buffaloes subjected to oocyte recovery once a week. Murrah buffaloes (n = 5) were synchronized for estrus by a single prostaglandin injection schedule. The animals were subjected to transvaginal oocyte retrieval (TVOR) once weekly for 6 weeks, starting from Day 7 of the oestrous cycle (Day 0 = day of oestrus). TVOR was performed using an ultrasound machine with a 5 MHz transvaginal transducer, single lumen 19-gauge, 60 cm long needle and a constant vacuum pressure of 50 mmHg. The number and size of follicles in each ovary was determined before puncture. The follicles were characterized on the basis of their diameter as small (3-5 mm), medium (6-9 mm) and large (> or = 10 mm). The oocytes recovered were classified as grade A, cumulus-oocytes complexes (COCs) with > or = 5 layers of cumulus cells; grade B, those with two to four layers; grade C, partially denuded oocytes; and grade D, completely denuded oocytes. The mean (+/- S.E.M) number of small, medium and large follicles, and the number of total follicles observed per animal per session, which was 2.2 +/- 0.3, 0.6 +/- 0.2, 0.9 +/- 0.1 and 3.7 +/- 0.3, respectively, did not differ between animals or between puncture sessions. Small follicles constituted a major proportion (59%) of the total observed follicles. A mean (+/- S.E.M) number of 3.0 +/- 0.3 follicles were punctured and 2.0 +/- 0.3 oocytes recovered per animal per session, with a recovery rate of 68%. Out of the total 61 oocytes recovered, 36 (59%) were of grades A + B whereas 25 (41%) were of grades C + D. In conclusion, this study describes the potential of cyclic Murrah buffaloes as donors of oocytes collected by repeated TVOR once a week, without any adverse effects on follicular growth and oocyte recovery. It also describes an efficient system for carrying out TVOR in buffaloes.     

Comparison of non-linear models to describe the lactation curves for milk yield and composition in buffaloes (Bubalus bubalis)

In order to describe the lactation curves of milk yield (MY) and composition in buffaloes, seven non-linear mathematical equations (Wood, Dhanoa, Sikka, Nelder, Brody, Dijkstra and Rook) were used. Data were 116 117 test-day records for MY, fat (FP) and protein (PP) percentages of milk from the first three lactations of buffaloes which were collected from 893 herds in the period from 1992 to 2012 by the Animal Breeding Center of Iran. Each model was fitted to monthly production records of dairy buffaloes using the NLIN and MODEL procedures in SAS and the parameters were estimated. The models were tested for goodness of fit using adjusted coefficient of determination root means square error (RMSE), Durbin–Watson statistic and Akaike’s information criterion (AIC). The Dijkstra model provided the best fit of MY and PP of milk for the first three parities of buffaloes due to the lower values of RMSE and AIC than other models. For the first-parity buffaloes, Sikka and Brody models provided the best fit of FP, but for the second- and third-parity buffaloes, Sikka model and Brody equation provided the best fit of lactation curve for FP, respectively. The results of this study showed that the Wood and Dhanoa equations were able to estimate the time to the peak MY more accurately than the other equations. In addition, Nelder and Dijkstra equations were able to estimate the peak time at second and third parities more accurately than other equations, respectively. Brody function provided more accurate predictions of peak MY over the first three parities of buffaloes. There was generally a positive relationship between 305-day MY and persistency measures and also between peak yield and 305-day MY, calculated by different models, within each lactation in the current study. Overall, evaluation of the different equations used in the current study indicated the potential of the non-linear models for fitting monthly productive records of buffaloes.     

Induction of parturition in water buffaloes (Bubalus bubalis )

Parturition was induced in ten buffaloes by combining treatments of dexamethasone and vetoestrol, so that they calved about one month before the expected term. Either dexamethasone alone (Group B) or dexamethasone and vetoestrol (Group C) was used. Another five animals served as controls (Group A). Calving was induced in four animals in group B and three animals in group C after two injections of the compounds four days apart. The average time from first injection to calving for these animals was 117.22 hr and 117.66 hr for groups B and C respectively. Induced calves weighed less at birth (P < 0.05) averaging 24.4 and 26.2 kg for groups B and C respectively, than controls (Group A; 30.20 kg). The body weight gain/week among calves was not significantly different (P > 0.05). The service period, number of services/conception and the milk yield of the buffaloes induced to calve was not significantly different (P > 0.05) from their previous records.     

Clinical, hematological, and biochemical findings of uterine torsion in buffaloes (Bubalus bubalis)

The aim of this study was to investigate uterine torsion in buffaloes, examine factors influencing the outcome of the disease, and to characterize the related alterations in blood constituents. A total of 126 buffaloes with uterine torsion were examined for stage of gestation, duration, degree, site and direction of torsion, as well as the location of the pregnant horn. Methods of correction were documented along with dam and calf survival. Blood samples were obtained from 20 buffaloes with uterine torsion and 10 healthy buffaloes for hematological and biochemical comparisons. Results showed that uterine torsion in buffaloes occurred in multi- (81.7%) and primiparous (18.3%), during late pregnancy (58.4%) and at full term (41.6%), clockwise (96%) and counter- clockwise (4%), at post- (98.4%) and precervical (1.6%), and was of high (52.3%), moderate (31%) and mild (16.7%) degrees. Torsion was predominantly (P=0.01) on same direction of the pregnant horn. Fetal and maternal mortalities occurred in 78.6% and 23.8% of the cases, respectively. The stage of pregnancy, and degree and duration of uterine torsion were major risk factors for fetal mortality (P=0.0001), while the stage of pregnancy and fetal viability were important risk factors for maternal mortality (P<0.05). There were significant (P<0.05) increases in monocytes, albumin, aspartate aminotransferase, creatine phosphokinase, blood urea nitrogen, and phosphorus and decreases in mean corpuscular hemoglobin concentration and globulin in the affected buffaloes. Time of occurrence and duration of torsion affected some of these parameters. Uterine torsion appears to be a serious problem in buffaloes that has certain peculiarities including time of occurrence, site and direction of torsion, and the high mortality rates. Uterine torsion adversely affects liver and kidney functions. Multiparous might be at greater risk of uterine torsion. The stage of pregnancy, as well as degree and duration of uterine torsion are risk factors for fetal and maternal mortalities.     

Genetic admixture and population structure analysis of Indian water buffaloes (Bubalus bubalis) using STR markers

Molecular Biology Reports - India has a vast riverine and swamp buffalo diversity adapted to various agro-ecological conditions. In the present study, genetic diversity data for 10 different...     

Effect of Spermine-NONOate on acrosome reaction and associated protein tyrosine phosphorylation in Murrah buffalo (Bubalus bubalis) spermatozoa

The present study was conducted to know the role of Nitric Oxide (NO) on the acrosome reaction (AR) in Murrah buffalo (Bubalus bubalis) spermatozoa. Ejaculated buffalo spermatozoa were washed, suspended in sp-TALP media containing 6 mg BSA/mL and cell concentration was adjusted to 50×10(6) cells/mL. The cells were incubated for 6h in the absence or presence of heparin (10 μg/mL) to induce capacitation. Fully capacitated spermatozoa were incubated in presence of 100 μg/mL Lysophosphatidyl choline (LPC, T1) or 100 μM Spermine-NONOate (T2) or 100 mM L-NAME (T3) or 100 μM Spermine-NONOate+100 mM L-NAME (T4) or 1 mM db-cAMP + 0.1 mM IBMX (T5) or 100μM H-89 (T6) or 100 μM Spermine-NONOate+100 μM H-89 (T7) in combination to induce acrosome reaction. The extent of AR was assessed by dual-staining of spermatozoa with trypan blue/Giemsa stain. AR-associated tyrosine-phosphorylated proteins were detected by SDS-PAGE followed by immunoblotting using monoclonal anti-phosphotyrosine antibody. Significant (P<0.05) number of spermatozoa were acrosome reacted in Spermine-NONOate (T2) treated cells but it was significantly (P<0.05) lower than LPC (T1) induced AR. Addition of Spermine-NONOate + L-NAME (T4) resulted in non significant (P>0.05) decrease in acrosome reaction. On addition of H-89 + Spermine-NONOate (T7) to sperm culture medium, resulted in significant (P<0.05) decrease in the percent acrosome reaction. Conversely, addition of db-cAMP+IBMX (T5, cAMP analogue) resulted in the significantly (P<0.05) higher number of acrosome reacted spermatozoa. Pattern of sperm protein tyrosine phosphorylation was also different in NO induced acrosome reaction compared to that of LPC. The present study concluded that nitric oxide is involved in acrosome reaction of buffalo spermatozoa by causing the tyrosine phosphorylation of proteins mainly p17 and p20 and through activation of cAMP/PKA pathway.     

Hormonal dynamics and follicular turnover in prepuberal Mediterranean Italian buffaloes (Bubalus bubalis)

The aim of this study was the investigation of hormonal and ovarian follicular dynamics in prepuberal buffaloes (Bubalus bubalis) bred in Italy. Eleven 5-9-month old buffalo calves ranging in weight from 122 to 270kg, maintained under controlled nutritional and environmental conditions, underwent 50 days of ultrasonographic ovarian follicular monitoring in the months of October-December. Blood sampling for E(2) and FSH determination and ultrasonographic monitoring using a 7.5MHz linear probe and an ALOKA SSD-500 monitor were performed daily. No differences in any of the parameters under study were highlighted when calves were divided into two weight categories (<200 and >200kg) and thus data were pooled. In this study, values are reported as mean+/-S.D. A range of two-six regular follicular waves was reported among calves with an average of 4+/-1.1. Overall interval (days) between wave emergence was 9.9+/-2.8 and largest diameters (mm) of dominant and first subordinate follicles were 8.4+/-1.2 and 4.8+/-0.6, respectively (P<0.05). With the exception of one calf, some minor follicular waves (short waves or SWs; 1.6+/-1), lasting <10 days (6.1+/-1.2) were reported. They were monitored contemporaneously on the ovary contralateral (n=7) or ipsilateral (n=3) to the main follicular wave. Growth rate (mm per day) of dominant follicles (DF) was significantly faster than for corresponding subordinate follicles (SF) and follicles of SWs (1.08+/-0.2 versus 0.79+/-0.1 and 0.83+/-0.1, respectively, P<0.05). The static phase (days) lasted longer in DF compared to SF and SW (5.4+/-1.8 versus 2.4+/-1.2 and 2.6+/-1, respectively, P<0.05). The regressing phase (mm per day) was similar among DF, SF and SW (0.86+/-0.2, 0.94+/-0.2 and 0.84+/-0.1, respectively, P=0.09). Episodic spikes of E(2) and FSH were reported, corresponding to wave development throughout the course of investigation. In conclusion, the majority of buffalo calves displayed a typical pattern of regular follicular development in conjunction with a dynamic trend of ovarian and hypophyseal hormones. Some minor follicle turnover was reported with parallel main follicular waves.     

An enzyme-linked immunosorbent assay (ELISA) to measure growth hormone level in serum and milk of buffaloes (Bubalus bubalis)

An indirect Sandwich ELISA to measure growth hormone level in serum and milk of buffaloes was developed. The assay was based on purified anti rbST IgG raised in rabbits and chicken and rabbit anti chicken IgG horseradish peroxidase. The assay was validated in terms of sensitivity, specificity, precision and recovery. Parallelism was demonstrated between the standard curve and serially diluted serum, milk and pituitary derived growth hormone. Sensitivity of the assay was 0.1 ng/ml. Recovery of exogenous bovine somatotropin from serum and milk ranged from 90 to 102% and 96 to 108% respectively. The intra and inter assay variations to measure growth hormone in serum and milk were 3.36 to 8.81% and 6.01 to 12.31% respectively. Statistical analysis for parallelism and cross-reactivity of rbST with serum of other species confirmed the reproducibility of the assay.     

Physico-chemical and immunological characteristics of pituitary prolactin from water buffaloes (Bubalus bubalis)

Prolactin (PRL) was purified from freshly frozen pituitary glands of water buffaloes (Bubalus bubalis) by a combination of existing procedures of Ellis and Jiang and Wilhelmi involving serial extraction of different pituitary proteins. The partially purified preparation was further fractionated on DEAF-Sephadex followed by Sephadex G-100 chromatography. This was finally purified on HPLC. This preparation was found to be homogeneous by SDS-PAGE and HPLC and had a single N-terminus amino acid (Threonine). The molecular size was estimated to be 24K ± 0.5 by SDS-PAGE and 25K by GPC-HPLC. The buffalo PRL gave a dose dependent inhibition curve in a rat liver based radio receptor assay with a potency of 30–35 L U./mg and also in a partial homologous RIA using ¹²⁵I-buffalo PRL and rabbit anti-oPRL serum giving a potency of 30I.U./mg. Metabolic labelling studies using ³⁵SO₄ ^2– with buffalo pituitary minces showed the incorporation of radioactive sulfate into immunoprecipitable PRL-like material. Physico-chemical characterization of the site of the linkage between sulfate and PRL revealed the presence of Tyr-O-SO₄ in bu-PRL. A high affinity monoclonal antibody (MAB) with Ka of 10¹⁰ L/M, belonging to IgG₁ isotype, and capable of cross reacting with ovine and bovine PRL was generated. This MAB was conformation specific as reduced and carboxymethylated PRL did not react with it. A homologous RIA system using this MAB has been standardised.     

Sarcocystis dubeyi (Huong and Uggla, 1999) infection in water buffaloes (Bubalus bubalis) from Egypt

Water buffaloes (Bubalus bubalis) are intermediate hosts for 4 species of Sarcocystis , i.e., Sarcocystis fusiformis and Sarcocystis buffalonis with cats as definitive hosts; Sarcocystis levinei with dogs as definitive hosts; and Sarcocystis dubeyi with an unknown definitive host but thought to be zoonotic. Currently, the latter species has been identified with certainty only from Vietnam. In the present study, sarcocysts of S. dubeyi are reported in 11 (30%) of 35 Egyptian water buffaloes from which the esophageal muscles were examined histologically. Sarcocysts were microscopic, measuring 180-250 × 70-110 μm in size. Ultrastructurally, the sarcocyst wall was 3.5-6.5 μm thick and had palisade-like villar protrusions which give it a striated appearance. The villar protrusions contained microtubules that were distributed along the whole villus. This is the first report of S. dubeyi from water buffaloes in Egypt.     

Genetic variation within and relationships among populations of Asian water buffalo (Bubalus bubalis)

Genetic variation at 53 protein-coding loci (25 polymorphic) was analysed for 17 water buffalo populations – 12 swamp, three Lankan and two of the Murrah breed (river type), to determine the magnitude of genetic differentiation and the genetic relationships among the populations. In accord with previous cytological studies, the Lankan buffalo clearly are river type. Significant deviations from Hardy–Weinberg equilibrium were shown for a number of locus–population combinations, with all populations but one showing significant heterogeneity in these deviations among loci. By contrast, heterogeneity among populations for each locus was much less, indicating locus-specific deviations, which suggest selection affecting allele frequencies at some loci. There was significant genetic differentiation among populations of both the swamp and river types. The differentiation among the swamp populations may reflect the geography of south-east Asia and the presumed spread of the swamp buffalo through this region. Phylogenies derived from pairwise genetic distance estimates show the clear separation of swamp and river types, but the topology of the swamp populations shows rather poor consistency with their geographic locations. For at least one population (Australia), it is clear that bottleneck effects have distorted the phylogenetic topology. Average genetic distances for both the swamp and river types, as compared with previous studies of livestock breeds, show that the genetic differentiation of each of these sets of populations is of the same order of magnitude as that among well-recognized and established breeds of other species.     

Hormonal stimulation and oocyte maturational competence in prepuberal Mediterranean Italian buffaloes (Bubalus bubalis)

The objective of this study was to determine the best combined hormonal treatment to utilize in order to obtain a high number of good quality in vivo and in vitro matured oocytes from prepuberal Mediterranean Italian buffalo calves (Bubalus bubalis). Transvaginal ultrasound follicular aspiration was employed to recover oocytes from antral follicles. Fifteen barn housed buffalo calves, between 5 and 9 months of age were used in this study and randomly divided into control (Group A) and treated groups. A commercially available preparation of 2000 IU eCG was administered to animals in the treatment groups, followed by 2000 IU of hCG given either 12 h (Group B), or 24 h (Group C) before ovum pick up (OPU). From the time of administration of eCG treatments, the best timing for hCG administration before OPU was determined and integrated with the administration of 500 IU of FSH-LH in a decreasing dosage protocol over 4 days (Group D). Expanded cumulus oocyte complexes (COCs) recovered from all groups were immediately fixed for later aceto-orcein staining. All other COCs were processed for in vitro maturation using standard procedures and then fixed and stained for assessment of nuclear maturation. Collectively, hormonal stimulation did not increase the number of ovarian antral follicles available compared to the control group (P > 0.05), but did result in higher output of medium (Group B: 9.8 +/- 7.1; Group C: 3.4 +/- 6.7; Group D: 15.6 +/- 4.9 versus Group A: 1.6 +/- 2.2) and large follicles (Group B: 44.8 +/- 22.9; Group C: 8.7 +/- 6.1; Group D: 70.2 +/- 10 versus Group A: 6.1 +/- 6.3). Administration of hCG 12 h before follicle aspiration proved to be the best strategy to obtain high numbers of immature and mature oocytes from antral follicles (P < 0.05; Group B: 70.8 +/- 12 and Group D: 82 +/- 12.6 versus Group A: 43.6 +/- 13.9 and Group C: 27.2 +/- 13.9). A significantly higher number of expanded COCs was obtained from hormonally stimulated groups compared to the control group (P < 0.05; Group B: 28.7 +/- 16.8, Group C: 16.3 +/- 5.9 and Group D: 27.1 +/- 16.9 versus Group A: 6.2 +/- 6). A higher oocyte maturational competence (P < 0.05) was found in Groups A, B and D (80.8 +/- 7.9, 87.5 +/- 8.2, and 86.5 +/- 4.3, respectively) compared to Group C (60 +/- 26.2). In conclusion, in prepuberal buffalo calves combined gonadotrophin stimulation protocols yielded higher numbers of medium to large size follicles compared to a control group. A high number of good quality oocytes were recovered by transvaginal ultrasound follicle aspiration, and a high rate of metaphase II progression was reached after in vivo and in vitro maturation.     

Genetic parameters for five traits in Africanized honeybees using Bayesian inference

Heritability and genetic correlations for honey (HP) and propolis production (PP), hygienic behavior (HB), syrup-collection rate (SCR) and percentage of mites on adult bees (PMAB) of a population of Africanized honeybees were estimated. Data from 110 queen bees over three generations were evaluated. Single and multi-trait models were analyzed by Bayesian Inference using MTGSAM. The localization of the hive was significant for SCR and HB and highly significant for PP. Season-year was highly significant only for SCR. The number of frames with bees was significant for HP and PP, including SCR. The heritability estimates were 0.16 for HP, 0.23 for SCR, 0.52 for HB, 0.66 for PP, and 0.13 for PMAB. The genetic correlations were positive among productive traits (PP, HP and SCR) and negative between productive traits and HB, except between PP and HB. Genetic correlations between PMAB and other traits, in general, were negative, except with PP. The study permitted to identify honeybees for improved propolis and honey production. Hygienic behavior may be improved as a consequence of selecting for improved propolis production. The rate of syrup consumption and propolis production may be included in a selection index to enhance honeybee traits.     

Postpartum ovarian follicular dynamics in primiparous and pluriparous Mediterranean Italian buffaloes (Bubalus bubalis)

The objective of this study was to monitor ovarian function in postpartum primiparous and pluriparous Mediterranean Italian buffaloes (Bubalus bubalis) during months of increasing daylength. Ovarian ultrasound monitoring was carried out for a total of 60 days from calving in 10 primiparous and 10 pluriparous buffaloes. Progesterone was determined from calving until a week after first postpartum ovulation. The study was undertaken during months of increasing day length. Time required for complete postpartum uterine involution was 31 +/- 1.0 and 33 +/- 1.3 days in primiparous and pluriparous buffaloes respectively (P = 0.1). The first postpartum ovulation was recorded on 4 primiparous and 8 pluriparous buffaloes (P = 0.16). Time for first postpartum ovulation to occur was 25.5 +/- 6.9 and 15.5 +/- 1.3 days in primiparous and pluriparous buffaloes, respectively (P = 0.07). Overall, 8 of the 12 first postpartum ovulations (66.6%) occurred in the ovary contra-lateral to the one bearing the gravidic CL, one out of 4 in primiparous and 3 out of 8 in pluriparous buffaloes (P = 1.0). Following a first postpartum ovulation, 3 primiparous and 4 pluriparous buffaloes displayed a complete wave of follicular development leading to a new ovulation. Ovulation following parturition was not recorded in 6 primiparous and two pluriparous buffaloes for the 60 days of ultrasound monitoring. Growth rate (mm/d) and largest size (mm) of first postpartum ovulating follicle was 0.95 +/- 0.18 and 1.07 +/- 0.07 (P = 0.4), and 13.5 +/- 0.8 and 14.1 +/- 0.4 (P = 0.4) in primiparous and pluriparous buffaloes, respectively. Following calving, the total number of available antral follicles (> or =2 mm) declined gradually towards the end of the study period. Follicles greater or equal to 3 mm in diameter on the contrary showed a prominent increase in the first 2 weeks from calving. The number of follicles greater or equal to 3 mm in diameter was significantly higher in the ovary contra-lateral to the one bearing the gravidic CL. A balance in the number of such follicles was reached toward the end of the first month. In conclusion, although some follicular activity was recorded in the ovaries of all buffaloes, true postpartum resumption of cyclicity in the months of increasing daylight hours was delayed in the majority of animals.     

Genetic parameters for test day milk yields of first lactation Holstein cows by random regression models

Covariance components for test day milk yield using 263 390 first lactation records of 32 448 Holstein cows were estimated using random regression animal models by restricted maximum likelihood. Three functions were used to adjust the lactation curve: the five-parameter logarithmic Ali and Schaeffer function (AS), the three-parameter exponential Wilmink function in its standard form (W) and in a modified form (W*), by reducing the range of covariate, and the combination of Legendre polynomial and W (LEG+W). Heterogeneous residual variance (RV) for different classes (4 and 29) of days in milk was considered in adjusting the functions. Estimates of RV were quite similar, rating from 4.15 to 5.29 kg². Heritability estimates for AS (0.29 to 0.42), LEG+W (0.28 to 0.42) and W* (0.33 to 0.40) were similar, but heritability estimates used W (0.25 to 0.65) were highest than those estimated by the other functions, particularly at the end of lactation. Genetic correlations between milk yield on consecutive test days were close to unity, but decreased as the interval between test days increased. The AS function with homogeneous RV model had the best fit among those evaluated.