scholarly journals Risk Factors and Treatment of Postpartum Anestrus in Cattle: The Case of Zebu

Author(s):  
Moussa Garba Mahamadou ◽  
Mani Mamman ◽  
Hamadou Issa

This literature review reports on risk factors for postpartum anoestrus in zebus and their potential treatments. Prolonged postpartum anestrus is one of the major factors limiting reproductive efficiency in cattle, particularly in Bos indicus cows in tropical regions, as it prevents a calving interval of 365 days from being achieved. During anestrus, ovulation does not occur despite ovarian follicular development, as the growing follicles do not reach maturity. This period is very variable and depends on various factors whose importance is relative or, on the contrary, essential. Some are specific to the animal (breastfeeding or food); others relate more to its social environment, season sanitary conditions. Several hormonal treatments have been used to induce ovulation and cyclicity in postpartum cows. Generally speaking, given the inconsistency of the effects or even their lack of practicability, treatments using a single or repeated injection of a gonadotropin-releasing hormone (GnRH) have been gradually abandoned in favour of progestagens. These are administered for 8 to 12 days on a continuous basis in the form of a subcutaneous implant (Crestar®), a vaginal coil (PRID®) or a CIDR. A prostaglandin injection is given two days before the implant is removed. The addition of an ECG treatment at the time of device removal, which increased plasma progesterone concentrations and pregnancy rates in anestrous postpartum suckled Bos indicus cows, may be useful to improve reproductive performance. This improvement requires a better understanding of the effect of different risk factors on the recovery of postpartum cyclicity.

2013 ◽  
Vol 25 (1) ◽  
pp. 201
Author(s):  
W. C. Marques Filho ◽  
F. C. Destro ◽  
E. Trevisol ◽  
C. M. Queiroz ◽  
M. C. Martins ◽  
...  

The aim of the present study was to evaluate the effects of subcutaneous implants of deslorelin (GnRH agonist-Suprelorin® 4.7 mg) on follicular dynamics and plasma profile of FSH, LH, and progesterone (P4) during the last 20 days of an implantation period of 70 days and after the removal of the implant until the detection of the first ovulation in Nelore cows (Bos indicus). Seven animals had their ovulation synchronized. At the day of the detection of ovulation they received subcutaneous implant of deslorelin. In the last 20 days of the period of treatment, ultrasound scans were taken every 2 or 3 days to characterize the follicular dynamics according to diameter: I (<4 mm), II (4–6 mm), and III (>6 mm). Blood samples were collected to measure plasma concentrations of FSH, LH, and P4. Results were tested by ANOVA, and difference between means was defined using Tukey’s test with significance levels of 0.05. During the 70 days of deslorelin treatment, none of the animals ovulated, despite the implant not suppressing all follicular development. The ultrasound finding was confirmed by P4 plasma concentrations (range: 0.05–0.31 ng mL–1). The normal P4 plasma concentration expected in cycling Nelore cows is about 3.8 ng mL–1 (Satrapa et al. 2010 Reprod. Anim. Dom. 45, 881–887). During the last 20 days of treatment, 4 animals presented follicular development with max diameter ranging through 4 to 6 mm, whereas in the 3 remaining animals, the observed diameter ranged through 9 to 12 mm. The secretion of FSH and LH was not entirely suppressed during the study (range: 1.69–1.39 and 1.37–1.07 ng mL–1, respectively). After the removal of the deslorelin subcutaneous implant, the period of restoration of the ovulatory capacity was 29 days, and the mean diameter of the preovulatory follicle was 12.5 mm. The P4 plasma concentrations during this time were low (range: 0.15–0.09 ng mL–1). During the recovery period, the phenomenon of follicular codominance and double ovulation in 2 animals (2/7) was observed. From the results obtained, it can be concluded that the total implant treatment of 70 days with deslorelin in cows inhibits ovulation by not allowing LH surge, although the follicular development is not completely depressed. The financial support of FAPESP, Fundunesp, and CNPq are acknowledged.


2015 ◽  
Vol 87 (9) ◽  
Author(s):  
Łukasz Dziki ◽  
Anna Puła ◽  
Konrad Stawiski ◽  
Barbara Mudza ◽  
Marcin Włodarczyk ◽  
...  

Abstractwas to assess patients’ awareness of the prevention and treatment of colorectal cancer.Patients diagnosed with colorectal cancer, hospitalised at the Department of General and Colorectal Surgery of the Medical University in Łódź during the period from January 2015 to April 2015, were asked to complete a questionnaire concerning their families’ medical case record, factors predisposing them to the development of colorectal cancer, the tests applied in diagnostics, and the treatment process. The questionnaire comprised 42 closed-ended questions with one correct answer. A statistical analysis of all answers was carried out.The study group consisted of 30 men and 20 women aged 27–94 years old. A strong, statistically significant negative correlation between a patient’s age and his/her awareness of the prevention and treatment of colorectal cancer was noted (p<0.001; r= −0.51). The study demonstrated a statistically significant relationship between the occurrence of neoplasms in a patient’s family (p=0.009) or, more specifically, the occurrence of colorectal cancer (p=0.008), and the awareness of the prevention programme. The women’s group was characterised by statistically significantly greater awareness of colonoscopy as a screening examination (p=0.004).Patients need more information on colorectal cancer, its risk factors, prevention, the treatment process, and postoperative care. Lack of awareness of the colorectal cancer issue can be one of the major factors contributing to the high incidence of this disease.


2017 ◽  
Vol 8 (2) ◽  
pp. 185 ◽  
Author(s):  
Jorge Rodolfo Canul Solis ◽  
Angel Trinidad Piñeiro Vázquez ◽  
Jeyderl Israe Arceo Castillo ◽  
José Alayón Alayón Gamboa ◽  
Armín Javier Ayala Burgos ◽  
...  

ABSTRACTRuminant animals contribute significantly to methane emissions in tropical regions. Nonetheless, there are few facilities available in those regions of the world for in vivo measurement of methane production in cattle. The aim of the present work was to describe the design, construction and operation of respiration chambers for in vivo measurement of methane production in cattle in Mexico. Locally available materials were used in the construction. Walls, roof and doors were constructed of thermic panels with two windows of acrylic at the front so the animal can be observed at all times. Chambers have an air volume of 9.97 m3. Air is drawn from the chamber at a rate of 500 L/min by the effect of mass action flow generators. Methane was measured in air samples with an infrared analyzer. Chambers operate under a slight negative pressure of around -500 Pa. Air temperature inside the chambers is kept at 23 °C with an air conditioner, while relative humidity is maintained at 55 % with a dehumidifier. Functioning of the chambers was evaluated in Bos indicus, Nelore cattle fed Taiwan grass (Pennisetum purpureum) and a concentrate (18 % crude protein), and measurements were made during runs of 23 h duration. Methane production was on average 173.2 L per day, while the emission factor was 17.48 L methane per kilogram o dry matter consumed. It concludes that this respiration facility is capable of measuring methane production accurately in cattle fed tropical rations.


Blood ◽  
1989 ◽  
Vol 74 (6) ◽  
pp. 2227-2236 ◽  
Author(s):  
NA Kernan ◽  
C Bordignon ◽  
G Heller ◽  
I Cunningham ◽  
H Castro-Malaspina ◽  
...  

Abstract Risk factors for graft failure were analyzed in 122 recipients of an allogeneic T-cell-depleted human leukocyte antigen (HLA)-identical sibling marrow transplant as treatment for leukemia. In each case pretransplant immunosuppression included 1,375 to 1,500 cGy hyperfractionated total body irradiation and cyclophosphamide (60 mg/kg/d x 2). No patient received immunosuppression prosttransplant for graft-versus-host disease (GVHD) prophylaxis. Nineteen patients in this group experienced graft failure. The major factors associated with graft failure were transplants from male donors and the age of the patient (or donor). Among male recipients of male donor-derived grafts a low dose per kilogram of nucleated cells, progenitor cells (colony forming unit-GM) and T cells was also associated with graft failure. Additional irradiation to 1,500 cGy, high dose corticosteroids posttransplant, and additional peripheral blood donor T cells did not decrease the incidence of graft failure. In addition, type of leukemia, time from diagnosis to transplant, an intact spleen, or the presence of antidonor leukocyte antibodies did not correlate with graft failure. To ensure engraftment of secondary transplants, further immunosuppression was necessary but was poorly tolerated. However, engraftment and survival could be achieved with an immunosuppressive regimen in which antithymocyte globulin and high dose methylprednisolone were administered both before and after infusions of secondary partially T- cell-depleted marrow grafts.


2020 ◽  
Vol 32 (2) ◽  
pp. 189
Author(s):  
M. Younis ◽  
M. Irfan-ur-Rehman Khan ◽  
A. Murtaza ◽  
M. Abbas ◽  
M. Z. Tahir ◽  
...  

Pakistan has 30.9 million heads of sheep; however, little information is available on their reproductive aspects. The objective of this study was to document ovarian physiology and endocrinology of Lohi ewes during the oestrous cycle. Nine Lohi ewes, synchronized by administering single prostaglandin F2α (PGF2a; Cyclomate, Star Laboratories), were monitored for ovarian follicular dynamics using transrectal ultrasonography (7.5MHz, HS-1500, Honda) for two consecutive oestrous cycles during the breeding season (September to November 2018). Changes in plasma progesterone and oestradiol-17β concentrations of ewes (n=9) were also determined during the oestrous cycle using radioimmunoassay. The interovulatory interval of Lohi ewes averaged 17.0±0.1 days, and the duration of follicular and luteal phases was 4.6±0.2 and 11.3±0.2 days, respectively. Follicles emerged in either 3- or 4-wave patterns, but the frequency of the 3-wave pattern was higher than that of the 4-wave (87 vs. 13%, respectively; P=0.05). Following ovulation (Day 0), follicles (=3mm) in 3-wave cycles (n=14) emerged on Days 0.7, 5.2, and 10.5, whereas in 4-wave cycles (n=2) follicles emerged on Days 0.1, 4, 8.5, and 11.5. The maximum diameter of preovulatory follicles and corpora lutea (CL) were 5.4±0.3 and 10.4±0.3mm, respectively. Regardless of the wave pattern, single ovulation occurred in each cycle. The CL was first detectable on Day 4±0.1, it reached maximum diameter on Day 9±0.1, and luteolysis began on Day 12.2±0.2 of the cycle. The peak plasma oestradiol-17β concentration (42.5±2.6 pgmL−1) was observed 48h before ovulation and correlated with the diameter of the preovulatory follicle during the follicular phase (r=0.84; P&lt;0.05). The peak plasma progesterone concentration (11.8±1.7ngmL−1) was observed on Day 9±0.1 and coincided with the diameter of CL throughout the oestrous cycle (r=0.93; P&lt;0.05). In conclusion, the majority of oestrous cycles in Lohi ewes had a 3-wave pattern and were mono-ovulatory in nature.


2020 ◽  
Vol 98 (2) ◽  
Author(s):  
Reinaldo F Cooke ◽  
Rodolfo C Cardoso ◽  
Ronaldo L A Cerri ◽  
G Cliff Lamb ◽  
Ky G Pohler ◽  
...  

Abstract Efforts to understand biological functions and develop management schemes specific to Bos indicus-influenced cattle raised in tropical and subtropical environments are critical to meet the increasing global demand for protein. In the United States, B. indicus breeds are mostly used to generate B. indicus × B. taurus crosses with increased thermal and parasite tolerance, while retaining some productive characteristics of B. taurus cattle. Although crossbreeding represents a proven strategy to improve cattle adaptation almost immediately, research has also attempted to identify B. taurus genetics that can withstand subtropical and tropical climates. Reduced milk production and delayed reproductive maturation appear to be related with tropical adaptation of B. taurus breeds, as a means to conserve energy under stressful conditions and limited nutrition. Moreover, longevity may be the ultimate adaptation response to unfavorable environments, and retention of bulls and heifers from proven cows is the recommended strategy to improve longevity in B. indicus-influenced herds. Besides selection for longevity, other aspects should be considered when planning reproductive management in tropical and subtropical regions. Bos indicus and B. taurus breeds have multiple differences pertaining to reproductive function, including age at puberty, ovarian dynamics, and pregnancy development. Nutritional strategies such as the stair-step regimen, and use of exogenous progesterone (P4) inserts are options to hasten puberty attainment of late-maturing B. indicus-influenced heifers. Yet, limited pharmacological alternatives are available for reproductive management of B. indicus-influenced females in the United States, which rely on GnRH-based protocols not specifically designed to the reproductive function of B. indicus breeds. In contrast, hormonal protocols based on exogenous P4, estradiol esters, and equine chorionic gonadotropin are available for use in B. indicus females in South America. These include protocols tailored to prepubertal heifers, anestrous cows, and cycling nulliparous or parous females, which often yield pregnancy rates of 50% to fixed-time artificial insemination. The global dairy industry also faces similar challenges in increasing demand and production as the beef industry. Selection of cows capable of sustaining optimal milk yield, reproductive success, and health status in hot and humid conditions is essential for optimal dairy production in subtropical and tropical regions.


2013 ◽  
Vol 91 (11) ◽  
pp. 829-836 ◽  
Author(s):  
C.E. Relton ◽  
N.C. Bennett ◽  
K. Medger

The pattern of ovulation in mammals is generally considered to be either spontaneous or induced by copulation, with environmental and social factors playing a key role in determining the specific mode of ovulation that would maximize the reproductive potential of the species. This study aims to determine whether the Namaqua rock mouse (Micaelamys namaquensis (A. Smith, 1834)) is a spontaneous or induced ovulator. Females were divided into three treatments differing in the degree of contact with a male. Namely, seven control females had no contact with a male; a further seven separated females had only chemical, auditory, and visual contact with a male; whereas six females had intermittent periods of full contact with a vasectomized male. Ovarian size, follicular development, and plasma progesterone concentrations were compared between the three treatments. Penile morphology was also investigated. Corpora lutea were found in all three treatments and the penis was smooth without any ridges or spikes, indicating that M. namaquensis is a spontaneous ovulator. Interestingly, however, the presence of a male (physical as well as just visual and olfactory) positively affected ovarian size, ovulation, and plasma progesterone concentrations. This signifies that although M. namaquensis ovulates spontaneously, male contact significantly influences ovulation rate and ultimately reproductive success.


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