Postpartum Anestrus Research Articles

Serum Biochemical Profile in Postpartum Anestrus Cows Treated with Herbal and Hormonal Protocols

Serum Biochemical Profile in Postpartum Anestrus Cows Treated with Herbal and Hormonal Protocols

Influence of breastfeeding and postpartum anestrus on the reproductive efficiency of the bovine female

The reproductive efficiency of a breeding herd is the most important tool when you want to improve the cattle industry of a farm. To evaluate the reproductive efficiency of cows, some features should be taken into consideration, as the number of conceptions and calves born in a year, and the number of calves weaned, for that to happen it is necessary that each cow can give birth to a calf every 12 months, this is only possible if the service period of these animals does not exceed 60 to 90 days. This paper will discuss the main factors leading to an increase in the length of service of females and consequently a decrease in reproductive efficiency. Several factors that affect female reproduction, including those that stand out are: the effect of breastfeeding and calf presence negatively affects resumption of estrous cycles of female, there are some forms of management of breastfeeding to help reduce this impact caused by the negative lactation. How cattle ranching requires management to create the flock, these animals suffer from stress caused by this management, which generates a negative effect on reproduction, which is often also affected by the seasons and heat stress. The postpartum anestrus and its pathophysiology are also very important when it comes to reproductive efficiency, as well as reproductive health and disease.

Evaluation of the bacteriological flora in the vagina of postpartum anestrus cattle before and after treatment with three progesterone implants

Thirty postpartum (>70 days) anestrus crossbred cows were treated with three standard hormonal protocols (CIDR TRIU-B, and P4 Sponge n=10 each) for induction of estrus and the findings were compared with a group of untreated anestrus cows (Blank Sponge n=10). 80 vaginal swabs were collected aseptically from each group just before insertion of Implants/Blank Sponge and at the time of Implant/Blank Sponge withdrawal for microbiological evaluation of vaginal mucosa. Total number of isolates obtained from all the swabs were 180. Out of 180 isolates, 72 (40.00%) isolates were Gram positive and 108 isolates were (60.00%) Gram-negative bacteria, indicating dominance of Gram- negative bacteria. Overall ratio of number of isolates per vaginal sample obtained in the present study was 2.25. The highest rate of isolation of bacteria per sample was recorded in the placebo group at the time of removal of placebo i.e. 2.6, followed by 2.5 by same group at the time of insertion, 2.3 at the time of TRIU-B removal, 2.2 at the time of TRIU-B insertion and P4 Sponge removal, 2.1 in CIDR at the time of removal and P4 Sponge insertion and lowest i.e. 2.0 in CIDR group at the time of insertion of implant. The frequency of single and mixed isolates observed in different groups of anestrus animals at the time of insertion and removal of implants showed predominance of mixed isolates over single isolates 63 (78.75%) vs 17 (21.25%), indicating dominance of mixed isolates over single isolates. E. coli, Staphylococcus, Proteus and Bacillus were the commonest isolates obtained before and after insertion of implants and Blank Sponge in post-partum anestrus cattle. The implant used and time/period of isolation did not alter the types of bacteria isolated.

Effect of Herbal, Homeopathic and Hormonal Drug on Hematology, Ovarian Cyclicity and Conception Rate in Postpartum Anoestrus Cows

The study was designed to assess the effect of herbal, homeopathic, and hormonal drugs namely Janova, Sepia and GnRH-PG-GnRH on hematological parameters, resumption of ovarian cyclicity and conception rate in 40 postpartum anoestrus and 8 normal cyclic cows. The anoestrus cows were randomly divided into five groups as G0, GI, GII, GIII, GIV; 8 cows in each group. Group G0 (untreated anoestrus) and GV (normal cyclic cows) served as positive and negative control, respectively. All cows in GI, GII, GIII and GIV were subjected to dewormer and mineral mixture supplementation for 10 days, while group GII, GIII, and GIV were additionally treated with Janova (herbal heat inducer), Sepia (a homeopathic drug) and GnRH-PG-GnRH (Ovsynch) protocol, respectively. Different therapeutic protocols revealed variable and significant effects on most of the hematological parameters, except differential leucocyte count, before and after treatment. The values were also significantly higher in normal cyclic than anoestrus groups. The oestrus induction response in G0, GI, GII, GIII, GIV, and GV was 0.00, 50.00, 62.50, 75.00, 87.50, and 100.00 %, and corresponding overall conception rates of 3 cycles were 0.00, 75.00, 80.00, 66.66, 57.13 and 75.00 %, respectively. In conclusion, aforesaid therapeutic regimens have definite bearings on oestrus induction as well as on conception and can be used to manage postpartum anoestrus in cows.

Comparative Evaluation of the Efficacy of Herbal Regimen for the Treatment of Post-partum Anestrus in Water Buffaloes

Comparative Evaluation of the Efficacy of Herbal Regimen for the Treatment of Post-partum Anestrus in Water Buffaloes

Association of taurine with ovarian follicular steroids and postpartum anestrus condition in Murrah buffaloes

Taurine is an abundant intracellular beta-amino acid majorly synthesized in the liver and transported through plasma. In mammals, taurine was reported to be involved in various physiological functions, including the enhancement of testosterone levels, the major estradiol precursor. Therefore, we hypothesize that taurine levels are associated with ovarian follicular steroids as well as with a reproductive problem called postpartum anestrus (PPA) in dairy buffaloes. To understand the taurine levels and its possible role in buffalo ovarian follicles, a correlation was established among taurine, estradiol, and testosterone levels in the ovarian follicular fluid. For this purpose, buffalo ovaries were obtained from the slaughterhouse, and follicular fluid samples were collected from small (<4 mm), medium (4–8 mm) and large (>8 mm) follicles. Taurine and steroid levels in the follicular fluid were analyzed by TLC and ELISA, respectively. Taurine and testosterone levels were significantly (P < 0.05) higher in the follicular fluid of small and medium follicles than large follicles, whereas the estradiol levels were significantly (P < 0.001) higher in the large follicles. Thus, taurine showed a positive correlation (r = 0.75) with testosterone and a negative correlation (r = −0.77) with estradiol in buffalo follicular fluid, indicating its possible role in testosterone function during follicular development. Interestingly, significantly (P < 0.001) lower plasma taurine levels in PPA (n = 50) than normal cyclic (n = 50) buffaloes represented its association with PPA. Therefore, our present study recommends the need for future nutrition studies on taurine supplementation to PPA buffaloes.

Development and evaluation of a dynamic simulation model of reproductive performance in pasture based suckler beef systems

The reproductive performance of a beef cow herd is largely a factor of efficient animal management strategies and genetics. The complex and cumulative nature of individual management decisions on a farm system's performance over multiple years mean that robust evaluation is time consuming and costly. A dynamic deterministic simulation model (Grange Reproductive Management Model; GReMM) with the capacity to replicate herd inventory dynamics over multiple reproductive cycles was developed using the Stella Architect dynamic modelling platform. The model is representative of a pasture-based spring calving suckled beef cow herd and is initialised by specifying individual farm parameters with respect to reproductive management, such as the breeding season duration, nutrition and management of the cow and calf postpartum. The focus was on the key factors which affect the duration of the postpartum anoestrus interval (PPAI); body condition score of the cow at calving (BCSc), postpartum nutrition (PPN), access of the suckling calf to the dam and, exposure of the dam to a fertile male. Model output was displayed in the form of a shift in calving distribution, the number of calves produced per cow bred per year and, percentage of cows culled due to barrenness. Three management scenarios were investigated to represent a herd implementing current industry best practice (BASE), a herd implementing intensive levels of reproductive management (Intensive reproductive management; IRM) and a herd implementing poor levels of reproductive management (Poor reproductive management; PRM). When evaluated in terms of calving distribution over six production cycles, both PRM and IRM showed a shift in the calving spread with a higher proportion of animals calving earlier and later, respectively, in the calving season compared to the BASE. This resulted in a 5% increase and a 14% decrease in six-week calving rates relative to BASE by year six, for IRM and PRM, respectively. Correspondingly, culling rates due to barrenness reduced by 0.9% and increased by 3.3% relative to BASE for IRM and PRM, respectively. The model developed offers a realistic and intuitive dynamic simulation model capable of investigating practical on-farm management decisions on herd reproductive performance.

Incidence and effects of subacute ruminal acidosis and subclinical ketosis with respect to postpartum anestrus in grazing dairy cows

Subclinical Ruminal Acidosis (SARA) and Subclinical Ketosis (SCK) are two of the most prevalent metabolic diseases of dairy cows, with impacts on reproductive performance. There is scarce literature about these diseases in dairy regions in Colombia. In 29 randomly selected herds in Pasto, Colombia, 249 dairy cows were followed weekly for two months postpartum to determine: 1) incidence risk of SARA and SCK; and 2) effects of SARA and SCK on the occurrence of postpartum anestrus (PA) at two months. Samples from ruminal liquor and blood were obtained one time per cow during the first week postpartum to determine presence of SARA (pH < 5.6) and SCK (1.0–2.9 mmol/L of blood Beta-Hydroxy-Butyrate), respectively. PA diagnosis was determined with ultrasound. Pregnancy risks at 30 and 60 days post-breeding (and assumed embryo losses between these days) were determined. Risk factors associated with PA were estimated through a mixed multi-level multivariable logistic regression model, adjusting for clustering of cows within herds. The incidence risks of SARA and SCK were 23.3% and 46.2%, respectively. Simultaneous occurrence of SCK and SARA (SCASCK) was present in 5.2% of the cows. In the final multivariable model, the occurrence of SARA (Odds Ratio: OR = 39.4), SCK (OR = 47.4) and SCASCK (OR = 68.5) was associated with increased odds of PA. Feeding a transition period diet was associated with reduced odds of PA (OR = 0.15). Second parity cows had significantly lower odds of PA than first parity cows (OR = 0.21). In conclusion, inadequate pre-partum and postpartum nutritional management of the herds increased the occurrence of SARA and SCK, which had adverse effects on reproductive performance.

Body condition score, parity, shelter cleanliness and male proximity: Highly associated non-genetic factors with post-partum anestrus in Murrah buffalo in field conditions

Postpartum anestrus (PPA) is a major reproductive problem in buffalo. Although both genetic and non-genetic factors influence the incidence of PPA, identifying associated non-genetic factors would be helpful for effective management of this problem. No systematic study, however, has been conducted to identify the association of non-genetic factors with PPA in buffalo, especially in field conditions. Data for 39 variables affecting postpartum anestrus interval (PPAI), health, nutrition, management and environmental status of the animals were collected on 575 buffalo from 15 villages. Data were analyzed using a general linear model considering PPAI as a dependent variable and the remaining 38 non-genetic parameters as independent variables. The results from the analysis indicated body condition score (BCS) variables, such as pelvic girdle score (P < 0.0001) and girth (P < 0.05), parity (P < 0.0001), shelter cleanliness (P < 0.001), male proximity (P < 0.005), amount and frequency of concentrate feeding during the early postpartum period (P < 0.05), general feeding frequency in a day (P < 0.05) and the treatments with oxytocin at the time of milking to facilitate milk release from the udder (P < 0.05) were associated with PPAI in Murrah buffalo. Plotting the PPAI residuals indicated the possibility of other unexplained factors, including genetics, that could also affect the differences in values for this variables in Murrah buffalo. In conclusion, a greater understanding of associated non-genetic factors with PPAI would help farmers in conducting proper managemental practices for early induction of reproductive cycles following parturition in Murrah buffalo.

Ultrasound guided diagnosis of anoestrus and its treatment in postpartum crossbred Holstein-Friesian cows

This study was undertaken to determine the feasibility of using ultrasonography for diagnosis of postpartum anoestrus followed by its effective management and treatment in crossbred (Holstein-Friesian X zebu) cows. A total of 57 crossbred lactating cows with unobserved oestrus for ≥60 days postpartum was examined by ultrasonography at Central Cattle Breeding and Dairy Farm (CCBDF), Savar, Dhaka. Cows were divided into silent oestrus and true anoestrus groups by ultrasonography. The pregnancy was diagnosed transrectally using ultrasonography 28 - 35 days after AI. Cows with silent oestrus were treated with Cloprostenol (500 μg) followed by AI or with 2 doses of Cloprostenol 10 days apart followed by AI at observed oestrus. The true anoestrus cows were supplied with anthelmintic and vitamin ADE injection with balanced nutrition, treated with Gonadorelin (500 μg) followed by AI or with Gonadorelin followed by injecting Cloprostenol at 7 days interval and AI at observed oestrus. All cows with silent oestrus and true anoestrus were divided into different body condition score (BCS), milk yield, age and parity groups to determine their influence on outcome of treatment. Out of 57 anoestrus cows examined, 56% were confirmed as silent oestrus and 44% were confirmed as true anoestrus. In silent oestrus, 71% cows showed cyclicity and 43% became pregnant after treatment with Cloprostenol and 78% cows showed cyclicity and 50% became pregnant after treatment with 2 doses of Cloprostenol 10 days interval (P&gt;0.05). In true anoestrus group, 60% cows showed cyclicity and 40% became pregnant when balanced diet was supplemented. Around 78% cows showed cyclicity and 44% became pregnant after treatment with Gonadorelin and 91% cows showed cyclicity and 55% became pregnant when Gonadorelin was followed by Cloprostenol at 7 days interval (P&gt;0.05). Significant (P&lt;0.05) influence of parity was observed in post-treatment cyclicity in true anoestrus cows. The Bangladesh Veterinarian (2019) 36(1 - 2): 33-41

203 Development and evaluation of a dynamic simulation model of farm management strategies affecting the reproductive performance of a suckled beef cow herd

Abstract Reproductive output in suckled beef cow systems is underpinned by a combination of genetics and the impact of efficient animal management strategies which given their cumulative nature, are difficult to evaluate. A dynamic simulation model (Grange Reproductive Management Model; GReMM) was developed replicating the reproductive performance of a suckled beef cow herd over multiple production cycles using the Stella Architect dynamic modelling platform (isee systems, Ventana, Lebanon, USA). Model inputs for farm parameters include dates and duration of breeding seasons in addition to nutrition and management of the periparturient beef cow. Specific management parameters pertaining to the duration of the postpartum anoestrus interval (PPAI), such as the body condition score of the cow at calving (BCSc), level of postpartum nutrition (PPN), management of the suckling calf and bio-stimulation of the dam pre-breeding are modelled. Outputs are displayed in the form of shifts in calving distribution, calving rates and calves per cow per year. Scenario analysis consisted of the implementation of a BASE scenario representative of current industry best practice (Normal reproductive management; NRM: BCSc, 2.75; PPN, 100 MJ ME/d; ad libitum suckling). Two further scenarios were developed representing a more intensively managed herd, with high levels of nutrition pre and post calving in addition to alternative reproductive management strategies (Intensive reproductive management; IRM), and a herd with a low level of nutritional management pre and postpartum (Poor reproductive management; PRM). Outputs generated in terms of calving distribution over six production cycles, indicated that a shift in the calving spread towards later in the calving season occurred in the PRM scenario, and a small improvement in reproductive efficiency evident in the IRM scenario over NRM. The model developed offers a decision support tool with the capability of evaluating practical on-farm management decisions on herd reproductive performance.

34 Reproductive management of beef females in tropical and sub-tropical environments

Abstract Bos indicus and Bos taurus cattle diverged from an evolutionary standpoint more than 110,000 years ago. Since then, Bos indicus cattle have undergone genetic adaptations beyond the commonly discussed increased thermo-tolerance and parasite resistance. Several physiological differences exist between Bos indicus and Bos taurus cattle, and it is important to consider these differences when establishing reproductive management strategies. It has been well described that Bos indicus cattle have a delayed onset of puberty and longer periods of postpartum anestrus, yet through the utilization of estrus synchronization protocols these challenges can be attenuated. However, when Bos indicus females are exposed to these protocols, they are known to have smaller dominant follicles, lower expression of estrus, and decreased pregnancy rates to artificial insemination (AI) when compared to Bos taurus females. These factors can be overcome through the utilization of estradiol and progesterone based synchronization protocols, which improve follicular dynamics and yield acceptable pregnancy rates to assisted reproductive technologies in cattle adapted to tropical or subtropical conditions. However, the use of estrogens for synchronization purposes is not permitted in the United States, and cattle producers need to rely on GnRH-based protocols. Another key difference between subspecies, is that Bos indicus females have greater antral follicle counts than Bos taurus females, which proves beneficial for in vitro embryo production. Therefore, an opportunity exists to explore the greater productivity of donors in embryo production in order to improve genetics in herds that utilize these breeds.

Exogenous kisspeptin (kp-10) resumes cyclicity in postpartum anestrus mithun cows

Present study was conducted to assess the effect of exogenous kisspeptin administration on estrus induction, Kiss1gene expression, endocrinological profiles and follicular development in post partum (PP) anestrus mithun cows. Animals who failed to resume cyclicity after day 90–100 of parturition were selected. Experimental cows were examined thoroughly through per-rectal as well as ultrasonograpic examination to confirm the anestrous status. PP anestrous healthy mithun cows (12), aged 5–6 years (body condition score: 5–6 of 10) were selected with uniform anestrus status and randomly divided into 2 groups namely treatment (Gr I) and control (Gr II), each group consist 6 cows. Anestrus cows in Gr 1 were injected with kisspeptin @ 1.30 μg per kg body weight at 3 day interval for 21 days after 90–100 days of post parturition whereas in control group, normal saline was injected as placebo. Blood samples were collected on the days of injection and at estrus in both the groups. Trans-rectal ultrasonography was done at 3 days interval till onset of estrus and ovulation to study the follicular development. Exogenous kisspeptin administration caused significantly early resumption of cyclicity in treatment as compared to control (24.64±10.43 vs 66.56±14.66 days) and significantly increased kiss1 and GPR54 mRNA expression in treatment as compared to control on the day of estrus (1.943±0.29 vs 0.424±0.062 and 1.84±0.31 vs 0.416±0.082, respectively). Similarly, circulating level of estradiol and follicle stimulating hormone (FSH) increased gradually after exogenous administration of kisspeptin, which reached peak on the day of estrus in treatment group (25.36±1.27 pg/ml and 15.65±1.22 ng/ml, respectively) whereas no significant difference was observed between days of treatment in control group except on the day of estrus (11.29±1.76 pg/ml and 9.86±1.06 ng/ml, respectively). Level of estradiol and FSH on the day of estrus was significantly higher in treatment as compared to control whereas non-significant difference was observed in plasma progesterone concentration. Number of medium and large follicles increased in treatment whereas only small follicles were observed in control group. Improved endocrinological profiles, follicle development and kiss gene profiles in post partum anestrous mithun cows following exogenous kisspeptin indicates that kisspeptin inducted or resumed the cyclicity in early.

Identification of novel proteomics markers involved in ovarian endocrinology of riverine buffalo (Bubalus bubalis)

ABSTRACT Long postpartum anestrus is one of the factors responsible for low reproductive efficiency. The present study was carried out to identify probable follicular fluid protein markers of postpartum anestrum buffaloes by proteomics approach. Ovum pick-up technique was used to collect follicular fluids from 23 buffaloes pertaining to postpartum estrus, anestrus and cystic follicular fluid. Pooled follicular fluids samples from each group were further divided into supernatant and cell lysate and subjected to two-dimensional gel electrophoresis. Densitometric analyses revealed the presence of 767 total protein spot and out of which 34 were unique in the studied groups. With the aid of mass spectrometry, the 34 protein spots were identified and among them apolipoproteins (A-I, A-II, A-IV), serum amyloid A-4, adenylate kinase 2, alpha-fetoprotein, heat shock protein beta-1, protein kinase C-binding protein, complement C1q subcomponent, integrin beta-7 and cadherin-23 have been established to play one or other role in ovarian endocrinology. Moreover, using bioinformatics tool, gene ontology and protein–protein interactions among the identified protein were also analyzed. To our knowledge, this is the first report on identification of proteins involved in postpartum anestrus of buffaloes from India which are to be validated further to establish its relationship with postpartum anestrus.

Pengaruh waktu perkawinan pasca beranak terhadap performa produktivitas sapi induk pada kondisi peternakan rakyat

The mating of the beef cow is important factors in beef cattle breeding. The research aims to obtain the mating time of the cow after calving in smallholder farmers. The study was conducted on Pasuruan and Probolinggo Regency, East Java Province. Observations were on productivities performance in Ongole-cross breed cows in smallholder farmers from 2010 to 2013. The study used a randomized block design with four treatment groups postpartum mating, namely Group I ( 120 days. The parameters measured included postpartum anoestrus interval/PPAI, service per conception (S/C), conception rate (CR), calf weaning time, and calving interval/CI, percentage of calf birth and death. Data were analyzed using ANOVA; followed by the Duncan test using SPSS. The values of PPAI in PO cows showed very significant differences (P<0.01) between the mating time groups. Calving Interval in group IV showed the highest value of 499.0±123.4 days (P <0.05) compared with group I, II, III. The highest CR value was in group III (79.45%) than I, II and IV. The highest calf mortality was in the group I (16.67%) than in group II, III and IV. The percentage of calf births in groups I, II, III, and IV are the same, but the lowest calf weaning time of obtained in group II mating was 92.8±22.5 (P<0.01) than group I, III and IV. In conclusion, the most efficient mating time was 60-<90 days after calving.

Intérêt de l’échographie dans le contrôle de la reproduction chez la chèvre : synthèse

L’application de l’échographie au contrôle de la reproduction chez l’espèce caprine suscite un intérêt grandissant. La présente synthèse vise à rapporter l’intérêt de l’échographie dans le suivi de la fonction de reproduction chez la chèvre. L’échographie permet d’établir un diagnostic précoce de gravidité chez la chèvre entre le 24e et le 29e jour après la saillie par voie transrectale et transvaginale, et entre le 34e et le 40e jour par voie transabdominale avec des sensibilités variant entre 65 % et 100 %. L’échographie permet également de déterminer le sexe et le nombre de fœtus, d’estimer le poids du fœtus et le stade de la gravidité, de diagnostiquer la mortalité embryonnaire/fœtale et la pseudo-gravidité. Elle est utilisée dans le diagnostic de l’anœstrus post-partum et le suivi de la dynamique folliculaire. Ces différentes applications ont permis de révolutionner la conduite de l’élevage des caprins. Cette synthèse apporte des éléments de repères utiles aux producteurs pour permettre d’organiser le rationnement des animaux gravides et de traiter les femelles chez lesquelles un anœstrus a été diagnostiqué pour les remettre à la reproduction.

Effects of Separation of Cows and Calves on Reproductive Performance and Animal Welfare in Tropical Beef Cattle.

Simple SummaryThis review summarizes knowledge on the separation of cows and calves and its effect on the onset of ovarian activity and animal welfare, principally in tropical beef cattle. After a brief introduction establishing the importance of calf separation to induce ovarian activity in their mothers and the welfare aspects that are jeopardized during this process, subsequent sections describe different strategies used for the separation of cows and calves, highlighting the effect of each method on beef cattle reproductive performance and welfare considerations of both cow and calf; conclusions and practical implications.Nursing a calf suppresses postpartum ovarian activity prolonging the period of anestrus. Diverse methods are used to reduce the effect of suckling; the most popular, restricted suckling, reduces the number of encounters mother-calf. Temporal weaning of the calf for periods of 24 h, 48 h, or even 72 h also suppress the effect of suckling and is commonly applied to cow-calf operations in the tropics. Early weaning of the calf, usually three to five months after birth, is a practice gaining popularity over the traditional system of weaning at seven months. Furthermore, the use of nose-flaps in the calf to avoid suckling is a common procedure in South America. Finally, weaning during the first week after calving is an established method to reduce postpartum anestrus. The objective of the present review is to discuss the effects of these methods on the reproductive performance of beef cattle and their animal welfare implications.

Vaginal Bacterial Profile in Buffaloes Following Treatment with Progesterone Insert

The objective of this study was to characterize the vaginal bacterial flora and subsequent conception rates after AI in buffaloes subjected to 3 different estrous induction regimes-the use of CIDR and use of two intravaginal sponges (Polyurethane sponges with micronized progesterone and Polyurethane sponges with micronized progesterone with Carboxy methyl cellulose). The estrus induction was 100% in Group I and II followed by 91.67% in group III. The pregnancy rates were Group I, II and III were 50.00, 66.67 and 54.55% respectively. All the vaginal swabs in all three groups yielded growth of bacteria and the predominance of mixed isolates over single isolates 81.94% vs 18.06% was indicative of dominance of mixed culture over single isolates. E. coli, Staphylococcus, Proteus and Klebsiela spp. were the commonest isolates obtained prior to insertion and after removal of implants in postpartum anestrus buffaloes. The gram positive bacteria were Staphylococcus, Streptococcus and Bacillus spp. while, gram negative bacteria were E. coli, Proteus and Klebsiella spp. These organisms could be considered as a part of the normal bacterial flora of the buffalo.

Identifying Early Conception Using Ultrasound in Ovsynch Treated Postpartum Anestrus Gir Cows

The aim of this study was to detect early conception using transrectal ultrasonography in postpartum anestrus Gir cows treated with Ovsynch protocol (Group-I, n=11), keeping the same number of normal cyclic cows as control (Group-II, n=11). Ultrasonography examinations were performed using a real-time B-mode ultrasound scanner equipped with 7.5 MHz convex array transducer on day 11, 22 and 32 post-AI to monitor ovarian structures and uterine changes. Cent percent of anestrus animals responded to the Ovsynch protocol with clear signs of estrus. The conception rates at induced and second estrus in the treatment group were 45.45 and 33.33%, respectively, with an overall conception rate of 2 cycles post-treatment as 63.63%. In the control group, first service, second service and overall conception rates of 2 cycles were 36.36, 14.28 and 45.45%, respectively. The results obtained were better with the Ovsynch protocol. Ultrasound scanning on day 22 and 32 revealed visualization of the fluid and embryonic vesicle, respectively. Early embryonic death occurred in one cow out of six between days 22 and 32 post-AI in ovsynch treated group.

RAPID COMMUNICATION: Multi-breed validation study unraveled genomic regions associated with puberty traits segregating across tropically adapted breeds1.

An efficient strategy to improve QTL detection power is performing across-breed validation studies. Variants segregating across breeds are expected to be in high linkage disequilibrium (LD) with causal mutations affecting economically important traits. The aim of this study was to validate, in a Tropical Composite cattle (TC) population, QTL associations identified for sexual precocity traits in a Nellore and Brahman meta-analysis genome-wide association study. In total, 2,816 TC, 8,001 Nellore, and 2,210 Brahman animals were available for the analysis. For that, genomic regions significantly associated with puberty traits in the meta-analysis study were validated for the following sexual precocity traits in TC: age at first corpus luteum (AGECL), first postpartum anestrus interval (PPAI), and scrotal circumference at 18 months of age (SC). We considered validated QTL those underpinned by significant markers from the Nellore and Brahman meta-analysis (P ≤ 10-4) that were also significant for a TC trait, i.e., presenting a P-value of ≤10-3 for AGECL, PPAI, or SC. We also considered as validated QTL those regions where significant markers in the reference population were at ±250 kb from significant markers in the validation population. Using this criteria, 49 SNP were validated for AGECL, 4 for PPAI, and 14 for SC, from which 5 were in common with AGECL, totaling 62 validated SNP for these traits and 30 candidate genes surrounding them. Considering just candidate genes closest to the top SNP of each chromosome, for AGECL 8 candidate genes were identified: COL8A1, PENK, ENSBTAG00000047425, BPNT1, ADAMTS17, CCHCR1, SUFU, and ENSBTAG00000046374. For PPAI, 3 genes emerged as candidates (PCBP3, KCNK10, and MRPS5), and for SC 8 candidate genes were identified (SNORA70, TRAC, ASS1, BPNT1, LRRK1, PKHD1, PTPRM, and ENSBTAG00000045690). Several candidate regions presented here were previously associated with puberty traits in cattle. The majority of emerging candidate genes are related to biological processes involved in reproductive events, such as maintenance of gestation, and some are known to be expressed in reproductive tissues. Our results suggested that some QTL controlling early puberty seem to be segregating across cattle breeds adapted to tropical conditions.