Repeat Breeder Cows Research Articles

Pemberian silase, complete feed, dan growth promoter pada sapi perah kawin berulang terhadap Services per Conception dan produksi susu

Repeat breeding is a reproductive disorder that harms dairy farmers because of the unachieved target to obtain one calf per year and decreased milk production. The repeat breeding syndrome can be caused by malnutrition. This study aimed to determine the effect of feeding silage, complete feed, and growth promoters in repeat breeder cows to restore the services per conception (S/C) and daily milk production. Thirty repeat breeder Holstein Friesian cows were divided randomly into three groups. The control group (P0) was fed 30-40 kg forage and 3-4 kg concentrate/head/day. Group P1 was given 8-10 kg silage or complete feed alternately every day; whereas P2 was given the same as for the P1 group, added with 10 ml growth promoter/head/day. Milk production and S/C were measured after six months of treatment. The results showed that the P1 and P2 groups returned S/C to normal (1.40 ± 0.52 and 1.30 ± 0.48), while the S/C of P0 group was 3.20 ± 0.63 (p <0.05). Daily milk production in the P1 and P2 groups (14.20 ± 1.40 and 14.60 ± 1.43 l/d) was also higher (p <0.05) than the control group (8.30 ± 1.06 l/d). It could be concluded that feeding silage and complete feeds alternately daily, with or without the addition of growth promoter, improved the S/C to the normal range and increased milk production.

Electrolytes Profile of Estrual Mucus of Gir Cows with Reference to Body Condition Score and Fertility

Fifty Gir cows of different reproductive status (10 = normal cyclic, 20 = repeat breeders and 20=induced estrus) were selected to determine the association of electrolytes mainly the macro-minerals profile of their estrual cervico-vaginal mucus (CVM) to their body condition score (BCS) and fertility post-AI. The overall pooled mean concentrations of calcium, inorganic phosphorus, magnesium, sodium and potassium obtained in CVM of Gir cows were 14.27 ± 0.33 mg/dL, 1.87 ± 0.13 mg/dL, 4.24 ± 0.10 mEq/L, 159.85 ± 5.52 mEq/L and 29.50 ± 0.78 mEq/L, respectively. The repeat breeding cows had significantly (p less than 0.01) higher calcium and lower inorganic phosphorus, sodium and potassium in their CVM than the normal cyclic and/or induced estrus cows. Similarly, the conceived cows, overall and of repeater group, had significantly (p less than 0.05) lower calcium and higher phosphorus, sodium and potassium than the non-conceived cows. However, no such variation was found in the magnesium content of CVM of these groups. Further, the levels of calcium in CVM showed an increasing trend, while other elements showed a decreasing trend with an increase in BCS from 2.5 to 3.5 (on 0-5 point scale) in all three categories of animals, but the differences were not significant for BCS within the group/category. It was thus inferred that significantly increased or widened Ca:P ratio and absolute lower levels of sodium and potassium in CVM could be responsible for conception failure and repeat breeding in dairy cows.

A Phylogenetic and Genotyping Study of Bovine Herpesvirus Type 4 (BHV-4) in Turkey

Infertility and reproductive infections are the huge problems for the diary management throughout the world. Bovine herpesviruses act an enormous role in these complicated problems. Bovine Herpesvirus Type 1 (BHV-1) is the most outstanding herpesvirus causing genital and uterine tracts infections among other reproductive viral agents, however, Bovine Herpesvirus Type 4 (BHV-4) is also responsible in terms of similar symptoms and diseases. The main aims of the study are both to investigate the underlying potential presence of BHV-4 in subclinical uterine tract infection, and both to perform molecular and recombination analyses. A herd including 25 repeat breeder cows were investigated by BHV-4. Two out of them were determined BHV-4 infected after a series of Polymerase Chain Reactions (PCRs) tests which able to amplify partial Glycoprotein B (gB) and Thymidine Kinase (TK) gene regions. Obtained sequences were analyzed by using phylogenetic and recombinational software, and two Maximum Likelihood (ML) tree have been constructed. To results, novel Turkish BHV-4 sequences fell into Genotype I in both constructed Maximum Likelihood (ML) phylogenetic trees, however, no recombination evidence has been observed in relevant software. This report is the first genotyping study of BHV-4 from Turkey. This study showed that Turkish BHV-4 substantially originated from European strains and might be observed in different clinical presentations. This suggests that BHV-4 should be deeply investigated by further molecular techniques and included in diagnostic panels for reproductive diseases viruses.

Implication of some biochemical parameters on normal cyclic and repeat breeding process in Bangladeshi dairy cows

Repeat breeding is one the most common reproductive disorders that hinders favorable productivity in domestic animals. Repeat breeding in dairy cows not only affects the fertility of the cattle to a considerable extent but also incurs great economic loss to the farmer. Biochemical profile can indicate the nutritional status and help in diagnosis and management of infertility in animals. Present study explores the implication of some biochemical parameters (total protein, bilirubin and some macro minerals as calcium, inorganic phosphorus and magnesium) on normal cyclic breeding process of Bangladeshi dairy cows. Current observation indicates that the lower calcium, inorganic phosphorus and magnesium concentrations might be associated with the ovulatory disturbances in repeat breeder cows. On the other hand, total protein and bilirubin do not play a significant role in causing repeat breeding problem in those cows. Thus, this study provides supportive evidence about the importance of calcium, inorganic phosphorus and magnesium in the resumption of repeat breeding condition.
 Asian J. Med. Biol. Res. June 2020, 6(2): 305-310

Treatment with an elevated dose of the GnRH analogue dephereline in the early luteal phase improves pregnancy rates in repeat-breeder dairy cows

This study sought to establish whether treatment with the GnRH analog dephereline in the early luteal phase could be useful to improve fertility in repeat-breeder cows (>3 inseminations). Dephereline was given 5–7 days after insemination, and effects of both a single and elevated (2.5 times) dephereline dose on pregnancy and subsequent embryo survival determined in repeat-breeder lactating dairy cows. The study population comprised 810 cows: 399 repeat-breeder cows and 411 non repeat breeders. To determine the effects of treatment on the pregnancy rate, three study groups were established: Control, no treatment (n = 269), DEPH, single dephereline dose (100 μg) (n = 270), or 2.5DEPH, 2.5 dephereline doses (250 μg) (n = 271). Recorded pregnancy rates in these groups were 28.6% (77/269), 31.9% (86/270) and 39.1% (106/271), respectively. Binary logistic regression analysis revealed a significant effect of the interaction treatment x repeat breeder on the pregnancy rate. This meant that the single dose and control treatments led to a pregnancy likelihood of repeat-breeder cows reduced by factors of 0.47 and 0.34, respectively, when compared to the 2.5 dose treatment as reference. Treatment had no effects on non repeat breeders. Based on odds ratios, treatment given either as a single or 2.5 dose increased the probability of an additional corpus luteum (more corpora lutea than embryos) in pregnant cows by factors of 5 or 5.4, respectively. Treatment had no effect on embryo survival. Our findings support the hypothesis that dephereline treatment in the early luteal phase after AI improves fertility in repeat-breeder cows. A dephereline dose 2.5 times higher than normal led to improved pregnancy rates, thus overcoming the impacts of repeat-breeder syndrome. Importantly, both the single and 2.5 dephereline doses increased the chances of pregnant cows having an additional corpus luteum, likely favoring embryo survival.

Characterization of native Escherichia coli populations from bovine vagina of healthy heifers and cows with postpartum uterine disease.

Even though Escherichia coli are common bacteria of the bovine vaginal microbiota, they represent an important pathogen that causes diseases in the reproductive tract and subfertility. However, the actual endometrial virulence profile of E. coli is poorly understood. The present study aims to characterize the phylogenetic structure and virulence potential of native vaginal populations of E. coli from healthy heifers (H), and cows with postpartum uterine diseases (PUD), such as metritis/endometritis (MT) or repeat breeder cows (RB). To this end, the virulence repertoire of 97 E. coli isolates was genotypically and phenotypically assessed. Most of them were assigned to phylogenetic group A (74%), followed by B1 (17%) and D (9%); RB strains were significantly (p < 0.05) more represented by B1. Seven of the 15 evaluated virulence genes (VFG) were detected and the most prevalent were fimH (87%), agn43 (41%) and csgA (35%); while traT (27%), fyuA (11%), hlyA (5%) and kpsMT II (5%) were observed in a lower proportion. Particularly, fyuA was significantly higher (p < 0.05) in MT cows whereas csgA showed the same behavior in PUD animals (p < 0.05). When comparing H and PUD strains, these last ones were associated to positive expression of biofilm, fimbriae curli/cellulose and motility; yet RB strains did not show motility. Vaginal B1 E. coli populations, that possess VFG (fyuA and csgA) as well as the expression of motility, curli fimbriae/cellulose and biofilm, may represent risk factors for endometrial disorders; specifically, those that also, have kpsMT II may have a pathogenic potential for causing the RB syndrome. Future research focusing on the detection of these strains in the vaginal microbiota of cows with postpartum uterine diseases should be done since the control of their presence in vagina could reduce the risk that they access the uterus during the postpartum period.

Cyclicity and Conception Rate after Induction of Lactation in Infertile Dairy Cows

Cyclicity and conception rate after induction protocol in infertile dry cows was assessed in terms of the induction of oestrus in anoestrus cows and conception in repeat breeder’s cows in the study. There were four anoestrous and two repeat breeder cows in G-1 out of them two anoestrus became cyclic, one repeater animal conceived after treatment. Where as in G-2, three anoestrus and three repeat breeder animals given induction protocol where two anoestrous cows became cyclic and two repeaters conceived. The analysis of data revealed higher response in G-2 as compared to G-1 (66.67 Vs. 50 %, respectively) with the higher conception rate (50 Vs. 33.33 %, respectively). It indicates better fertility response in G-2 as compared to G-1.

The effect of heatsynch protocol on repeat breeding dairy cows

The aim of this study was to know the incidence of repeat breeding in dairy cows and to know the effectiveness of Heatsynch protocol on dairy repeat breeding cows. The study was conducted in two stages. The first stage, all dairy cows were recorded and clinically examined through palpation per rectum and for their reproductive statuses. Parameter measured in the study was the incidence of repeat breeding. The second stage of the study was that the repeat breeder cows subjected to Heatsynch protocol for estrus induction. The protocol was GnRH injection on day-0, followed by PGF2α, estradiol injections on day-7 and day-8, respectively, and inseminated artificially on day-9. The results of the study indicated that the incidence of repeat breeding was 41.6%. The Heatsynch protocol was successfully increase the number of pregnant repeat breeder cows; 75%, higher compared to untreated repeat breeder cows; 20%. It can be concluded that high incidence of repeat breeding in dairy cows. Heatsynch protocol can be used to treat repeat breeder cows and improve the reproductive efficiency.

Insulin-like growth factor-1 gene expression in the endometrium of repeat breeder cows after the administration of presynch-10 and ovsynch protocol

The aim of this study was to investigate the effects of using presynch-10 and ovsynch synchronization protocols on endometrial expression and serum levels of insulin-like growth factor-1 (IGF-1) that thought to play roles during endometrial healing process in cows diagnosed with repeat breeder syndrome (RBS) and subclinical endometritis (SE). A total of 40 Holstein-Friesian cows identified as having RBS and SE were used. The animals in Group 1 (G1, n=20) were applied presynch-10 and ovsynch furthermore, biopsy and blood samples were collected both before and after administration. Biopsy and blood samples were taken from the animals in Group 2 (G2, n=20) without performing any synchronization. The IGF-1 gene expression profiles were determined in all samples using RT-qPCR. Even though the level of IGF-1 expression increased in samples taken after synchronization in G1, it was not statistically significant (P&amp;gt;0.05). There was no statistical difference in serum IGF-1 levels between G1 and G2 (P&amp;gt;0.05). In conclusion, the expression of the IGF-1 gene in the endometrial tissue of RBS cows with SE was identified, but the evidence suggests that the synchronization protocols in question had no significant effect on the gene expression profile being investigated.

Short communication: Evaluation of tubal patency in repeat breeder Holstein cows

Aim of study: To evaluate tubal patency in repeat breeder Holstein cows with the purpose of estimating the frequency of oviduct obstruction as a cause of the repeat breeding syndrome.Area of study: Lugo (NW Spain)Material and methods: In 50 repeat breeding cows, a solution of the dye phenol-sulphon-phthalein (PSP) was instilled into one uterine horn with the aid of a balloon catheter. Urine was collected 15, 25 and 45 min post-PSP infusion. Urine of a reddish color was used as indicator of tubal patency, as the PSP had passed across the oviduct into the abdominal cavity and was eliminated in urine. The other oviduct was evaluated on a different day.Main results: Of the 50 cows tested, 44% had some degree of oviduct obstruction: 4% had bilateral oviduct occlusion, 20% unilateral oviduct occlusion, 16% bilateral oviduct stenosis and 4% unilateral oviduct stenosis. No significant relationship could be established between tubal impermeability and postpartum reproductive or metabolic diseases.Research highlights: Tubal stenosis or occlusions were frequent and they are likely to contribute to the repeat breeding syndrome in dairy cows; thus, tubal patency should be routinely evaluated in repeat breeders. The PSP test is easy to perform, well tolerated by animals, and allows evaluating both oviducts separately.

Effect of seminal plasma infusion into the vagina on the normalization of endometrial epidermal growth factor concentrations and fertility in repeat breeder dairy cows

Epidermal growth factor (EGF) concentrations in the uterus show two peaks on days 2–4 and 13–14 during the estrous cycle in fertile cows. Loss of the two peaks has been linked to reduced fertility in repeat breeder cows. This study aimed to examine the effect of seminal plasma (SP) on normalizing endometrial EGF concentrations and restoring fertility in repeat breeder cows with low EGF concentrations on day 3. In study 1, we examined the effect of the deposition sites (the vagina and uterus) of SP on the endometrial EGF concentrations in repeat breeder cows. SP infusion into the vagina, but not uterus, on the first day of the estrus cycle (day 0) normalized the endometrial EGF concentrations (≥ 4.7 ng/g tissue weight) on day 3. In study 2, the effect of SP volume (0.5 and 10 ml of SP and 0.5 ml of SP diluted to 10 ml) on EGF concentrations was examined. All groups with SP infusion had increased EGF concentrations on day 3, and cows with 10 ml of SP and 0.5 ml of SP diluted to 10 ml showed the highest levels of EGF concentrations. In study 3, we examined the effect of SP infusion on fertility. SP infusion normalized two peaks of endometrial EGF concentrations in about 60% of repeat breeder cows and produced more pregnancies than the controls (44.4 vs. 19.4%). Therefore, we concluded that SP may contain an activity to normalize the EGF profile and restore fertility in repeat breeder cows with altered EGF profiles.

Effect of progesterone, human chorionic gonadotropin and progesterone + human chorionic gonadotropin treatment on conception rates in repeat breeder cows

The aim of this study was to investigate the effects of hormonal support on the pregnancy rate in repeat breeder cows. Prostaglandin F2α + Ovsynch oestrus synchronization protocol was applied to the cows. Following the fixed time insemination (day 0), the cows were divided into 4 groups. In Group 1 (n = 42), progesterone releasing intravaginal device (PRID) was placed vaginally at 84 h and removed on the 9th day after the artificial insemination. In Group 2 (n = 40), the cows were administered human chorionic gonadotropin (hCG) on the 7th day. Group 3 (n = 45) was applied a combination of progesterone and hCG. Group 4 (n = 42) was not given any treatment. Blood samples were collected from all cows 4 times on days 3.5, 7, 12, and 18 to evaluate progesterone concentrations. The pregnancy rates were 40.47%, 37.50%, 44.44%, and 30.95% in Group 1, 2, 3, and 4, respectively (P &gt; 0.05). In addition, in cows with progesterone concentrations &lt;2 ng/ml on day 3.5, the pregnancy rates were found to be lower than in the cows with progesterone concentrations &gt;2 ng/ml in Group 4 (P &lt; 0.05). Progesterone supplementation in cows with progesterone concentrations &lt; 2 ng/ml appeared to increase pregnancy rates (P &lt; 0.05) in Groups 1 and 3. As a result, post-insemination hormonal applications in the repeat breeder cows did not increase the pregnancy rate. However, it was concluded that determination of progesterone concentrations on day 3.5 following artificial insemination and then hormonal support in the cows with low concentrations would increased the pregnancy rate.

Systemic levels of iron, phosphorus, and total protein in normocyclic versus repeat breeder Holstein Friesian crossbred cows of Kesharbag, Chitwan, Nepal.

Background and Aim:In repeat breeding, a sexually mature cow fails to conceive even after three or more consecutive inseminations despite being without any clinically detectable reproductive anomalies. This is a major cause of economic loss in livestock farms, particularly in developing countries, where humans and livestock directly compete for food, and the mineral content of animal feed is rarely checked. This study investigated the association between systemic iron, phosphorus, and total protein and estrous cyclicity in crossbred Holstein Friesian cows.Materials and Methods:Blood samples were collected from 10 normal cyclic and 10 repeat breeder cows 12 h after the onset of estrus. Serum was separated, and iron, phosphorus, and total protein were quantified with spectrophotometry, using standard controls for all three measurement parameters (iron, phosphorus, and total protein).Results:Iron and phosphorus levels were significantly (p<0.05) lower in the repeat breeders group than in the normocyclic group, but no significant differences were found in total protein levels.Conclusion:Repeat breeding is associated with systemic iron and phosphorus levels but is independent of total protein level.

Identification of pathogenic microorganisms of repeat breeder dairy cows and a hyperimmune treatment approach

Objective: To investigate the bacterial infections in repeat breeder dairy cows and to evaluate the treatment effects of hyperimmune serum against two main endometritis bacteria, Escherichia (E.) coli and Trueperella pyogenes.Methods: A total of 29 Holstein multiparous cows with three or more unsuccessful artificial inseminations were carried out and examined to confirm the absence of reproductive tract abnormality and vaginal discharges. Uterine lavage was performed to collect uterine samples for bacterial and fungal cultures. In addition, polymerase chain reaction (PCR) was done to detect Trueperella pyogenes, E. coli, Fusobacterium necrophorum, and Prevotella melaninogenicus. The cytological study was done on cervical mucus. The hyperimmune serums produced against Trueperella pyogenes and E. coli were infused into the uterus of repeat breeder cows and two doses of prostaglandin F2α were administrated intramuscularly within 14 days’ interval.Results: There were 10 positive samples in the bacterial culture with 19 isolations and no growth of the main causative bacteria of endometritis. In the PCR method, no Trueperella pyogenes, Fusobacterium necrophorum, and Prevotella melaninogenicus were found. However, 11 positive samples of E. coli were identified by PCR. Cladosporium was detected in one case of repeat breeder cows. The median (interquartile range) of neutrophils in vaginal discharge was 12 (22.5). Eighteen from twenty-nine (62.1%) repeat breeder and eight from eleven (72%) cows with E. coli infections in PCR were made pregnant in the first artificial insemination after treatment by intrauterine infusion of hyperimmune serum and prostaglandin F2 α.Conclusions: Intrauterine administration of hyperimmune serum could be an alternative to antibiotics for the treatment of repeat breeder cows.

Effect of dietary n-3 polyunsaturated rich fish oil supplementation on ovarian function and interferon stimulated genes in the repeat breeding cow

Dietary n-3 polyunsaturated fatty acids (n-3 PUFA) improve utero-ovarian functions and embryonic survival in postpartum dairy cows. Because early embryonic mortality is the major cause of repeat breeding (RB) in cows, there was investigation of the effect of dietary supplementation of n-3 PUFA [eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)] rich fish oil (FO) from −2 to +2 weeks of artificial insemination on the size of preovulatory follicle (POF), serum progesterone (P4) and relative abundance of the mRNA of interferon stimulated genes (ISG) that encode for these proteins in the peripheral blood leukocytes (PBL) in the RB cow (n = 12). The diet of control group was supplemented with palm oil (PO). The results indicated serum concentrations of EPA and DHA were greater by 4.6- and 3.5-fold, respectively at the end of feeding study in the RB cows of the FO group. The diameter of POF was larger by 2.2 mm in FO group; however, serum P4 did not vary from day 14–20 post-artificial insemination. Greater abundance of ISG mRNA transcripts such as ISG15, RTP4, Mx2 and OAS1 in the PBL of pregnant cows of FO group indicates day 20 conceptuses produced more IFN-τ. It is concluded that supplementation of FO during the breeding period increased the size of POF and enhanced the abundance of ISG mRNA transcripts in RB cows that became pregnant.

Endometrial expression of various genes (ISGs, PPARs, RXRs and MUC1) on day 16 post-ovulation in repeat breeder cows, with or without subclinical endometritis

Our objective was to elucidate differences in endometrial mRNA expressions of interferon-stimulated genes (ISG15, CTSL1, RSAD2, SLC2A1, CXCL10, and SLC27A6), peroxisome proliferator activated receptors (PPARA, PPARD, and PPARG), retinoic acid receptors (RXRA, RXRB, and RXRG), and mucin 1 (MUC1) in repeat breeder cows, with or without subclinical endometritis (RB + SE and RB, respectively) and normal cows on day 16 post-ovulation (n = 4 cows per group). The CXCL10 and SLC27A6 mRNA abundances were greater for normal cows compared to RB and RB + SE cows (P < 0.05 and P < 0.01 respectively) whereas ISG15 and SLC2A1 mRNA abundances were greater for normal cows compared to RB + SE (P < 0.05). The SLC27A6 mRNA abundances were greater for RB versus RB + SE (P < 0.01). Similarly, PPARD, PPARG, RXRA and RXRG mRNA abundances were greater for normal cows compared to RB and RB + SE (P < 0.01 and P < 0.05, respectively). Abundances of PPARD, PPARG, RXRA and RXRG mRNA were greater for RB versus RB + SE (P < 0.05) and MUC1 was lower in abundance in normal cows compared to RB or RB + SE (P < 0.05). Key predicted molecular functions were binding, signal transducer and transporter; key biological processes were cellular, localization and metabolic; key cellular components were cell part, membrane and organelle components; and key protein classes were nucleic acid binding, receptor, and transcription factors. Gene networking analysis highlighted interactions and pathways involving PAPRs, RXRs, and MUC1, notably among PPARD, PPARG, and MUC1. In conclusion, endometrial mRNA expressions of ISGs (CXCL10 and SLC27A6), PPAR isomers (PPARD and PPARG), and RXRs (RXRA and RXRG) were in lower abundances, whereas MUC1 expression was more abundant in RB or RB + SE compared to normal cows on day 16. In addition, ISG15 and SLC2A1 genes were less abundant in RB + SE versus RB or normal cows. Altered expression of these uterine genes and associated potential impairment in embryo elongation and implantation may promote embryonic loss in repeat breeder cows. Furthermore, interactions among PPARD, PPARG and MUC1 may be therapeutically exploitable.

Progesterone level of normal cycling and repeat breeding Ongole grade cows

The present study was carried out to compare plasma progesterone level of normal cycling and repeat breeding Ongole grade cows. On the beginning of the luteal phase, blood samples were collected from 15 fertile and 15 repeat breeding Ongole grade cows. Progesterone hormone level was measured using progesterone hormone kit (DRG, Germany). The data were analyzed using independent sample t-test to determine the differences of progesterone level in repeated breeding and fertile cows. The finding of the study showed significant different progesterone level of between repeat breeding and fertile cows. Repeat breeding cows were found to have lower levels of progesterone level (1.17 ± 0.39 ng/ml) than that of fertile cows (3.07 ± 0.33 ng/ml). Finally, progesterone level of repeat breeding Ongole grade cows was lower than fertile cows. Low level of progesterone can have some effects on reproductive problems as repeat breeding.

Efficacy of different estrus synchronization protocols in repeat breeder cows

The work was conducted in 272 repeat breeder cows diagnosed with functional form of infertility, i.e. luteal insufficiency and ovulatory defects. The objective of present study was to evaluate the efficacy of synchronization protocols in functionally infertile repeat breeder cows. These cows were divided into 4 treatment, viz. Ovsynch, Ov-cosynch, Doublesynch, Heatsynch and one control group. The overall conception rate of Ovsynch treatment protocol was significantly higher than control cows. Similarly, the mean diameter of dominant follicle in cows treated with Ovsynch protocol was significantly higher than cows treated with Doublesynch and Heatsynch protocols. Also, the mean diameter of dominant follicle prior to artificial insemination in the cows treated with Ovsynch protocol was significantly higher in comparison to control cows. In conclusion, Ovsynch protocol fared better in terms of conception in repeat breeder cows.

Evaluating sire effects on cow fertility: Timed AI and repeat-breeder dairy cows

In this single herd observational study, there is investigation of the effects of 81 sires (with 11,424 artificial inseminations) on conception rates in 1790 Holstein cows for 5 years. Sires were catagorized based on the published sire conception rate (SCR) into different sire fertility groups (low, average and high fertility sires). The performance of different-sire fertility groups was assessed in timed artificial insemination (TAI) and repeat-breeder (RB) cows. With this aim, two logistic regression models with sire, inseminator, cow, and lactation random effects were applied to data on pregnancies assessed at days 30 and 70 post-insemination. Fixed effects of sire fertility group, sire breed, cow-fertility status, insemination type, postpartum problems, milk yield, temperature humidity index, and year were evaluated. Results from the analysis indicated there was a significant individual sire effect on conception rates, and large heterogeneity in values for this variable among sires. Results indicate that SCR could be assessed to predict low fertility sires reasonably well, and the predicted probabilities for pregnancy per AI (P/AI) at 30 and 70 days post-insemination for high fertility sires were consistent for the most part with values for the SCR. The sire breed did not affect conception rates at days 30 and 70 post-insemination nor its interactions with insemination type (estrous detection AI (EDAI) compared with TAI) and cow-fertility status (RB compared with non-RB). Predicting response probabilities for sires with at least 100 inseminations in each insemination group resulted in greater conception probabilities in cows in which there was EDAI than those in the TAI group.

Serum lipid profiles in repeat breeding and normal cyclic cows in Bangladesh

Repeat breeding reduces calf and milk production in crossbred cows. Serum lipid profiles in repeat breeding (RB) and normal cyclic (NC) cows were examined. Blood samples from 10 of each type cows were collected and TC, TG, HDL and LDL were estimated by spectrophotometer using enzymatic commercial kit. The serum TC in NC and RB were found within normal range (167.43 vs. 174.95mg/dl) (P&gt;0.05). The TG in RB cows (121.92mg/dl) were significantly (P&lt;0.05) higher than NC cows (115.03mg/dl). The HDL and LDL in NC (49.74 and 98.82mg/dl) and RB cows (46.40 and 103.09mg/dl) were found within normal range (P&gt;0.05). Serum lipids have no effect on repeat breeding problem for crossbred cows.&#x0D; Asian J. Med. Biol. Res. June 2019, 5(2): 158-161