Influence of feto-pelvic disproportion on milk cows fertility

The aim of the study was to evaluate relations between feto-pelvic proportion and further fertility of milk cows, select proportions and critical values of disproportion best predicting cows with lower fertility as a result of difficult calving as well as to evaluate fertility of cows selected on the basis of chosen criteria. The study was carried out on black-and-white and red-and-white Polish Holstein-Friesian cows in six farms diversified by the number of livestock (from 10 to 20 to over 180 cows) and milk yield (from 6.563 – 9.788 kg/305 days). In total 100 parturitions were analysed (one in each cow) resulting in giving birth to one calf, without complications related to foetus presentation, posture, and position or the need for caesarean section or fetotomy and retained placenta. Analysed parturitions were the result of artificial insemination pregnancies in 53 cases with semen from 33 polish-HF bulls and in 47 cases with semen from 26 the world HF bulls. Considering critical values of chosen feto-pelvic proportions, there is possibility of choosing cows, where more than every third cow had usually delayed over 90 days calving-conception period and more than every fourth became pregnant after at least three inseminations

Influence of unilateral ovariectomy performed before ovulation on ovarian function, steroid hormone levels and development of porcine fetuses

Corpus luteum (CL) activity is closely linked with initiation and maintenance of pregnancy and with fetal development. The present study was aimed to analyze the impact of unilateral ovarian removal on ovarian function, steroid hormone level and fetal distribution and development. Unilateral ovariectomy (uni-OVX) was performed in gilts one day before ovulation (group SHORT, n = 24), 20 days before subsequent ovulation (group LONG, n = 23) or ovaries remained intact (group INTACT, n = 22). Gilts were inseminated by single fixed-time laparoscopic intrauterine insemination (LIUI) after hormonal estrus synchronization. Two days before the end of a 15 day long altrenogest feeding, a part of gilts (n = 23) were surgically fitted with a jugular vein catheter and blood samples were collected to determine of estradiol (E2) and progesterone (P4) concentrations. All animals were slaughtered on day 30 of gestation and ovarian features as well as the number, weight and distribution of fetuses recorded. Altogether, 48 gilts (70%) were pregnant and pregnancy rates did not differ between groups. Short term uni-OVX affected CL number compared to intact and long term OVX gilts (9.9 ± 0.8 vs. 20.6 ± 1.9 and 17.5 ± 0.8; P < 0.05) and the number of fetuses (8.7 ± 0.5 vs. 15.0 ± 1.0 and 14.4 ± 1.1; P<0.05), respectively. Weights of individual CL were not influenced by treatment. Fetuses were differently distributed in the uterine horns after uni-OVX. A higher (P<0.05) proportion of fetuses was present always in the horn which bore the ovary. In all groups, weights of fetuses from uterine horns with an active ovary was similar; however, fetuses of the OVX horn of the SHORT group were lighter (P < 0.05). Steroid hormone profile was typical for pregnant gilts, but differences were observed between groups. Both, the preovulatory E2 concentrations and the early luteal phase P4 levels were higher (P < 0.05) in gilts of the INTACT and LONG groups. In summary, compared to intact gilts, only long term uni-OVX could compensate ovarian development. Short term uni-OVX affects (1) the total number of CL and fetuses, (2) the distribution and weight of fetuses in the uterine horns and (3) steroid hormone levels. Therefore, the time window, but not the uni-OXV per se, which alters the local supply of progesterone, has an impact on fetal development and survival

Expression and cellular distribution of cyclin-dependent kinase 4 (Cdk4) and connexin 43 (Cx43) in porcine oocytes before and after in vitro maturation

It is recognised that connexin 43 (Cx43) and cyclin-dependent kinase 4 (Cdk4) are involved in the cumulus cell-oocyte communication via gap junctions and the control of cell cycle progress. However, little is known about their mRNA expression pattern and encoded proteins distribution in porcine oocytes during in vitro maturation (IVM). Cumulus-oocyte complexes (COCs) were collected from 31 puberal crossbred Landrace gilts and analysed for their Cdk4 and Cx43 mRNA expression using RQ-PCR and for the respective protein expression by confocal microscopic observations. An increased Cdk4 and Cx43 mRNA expression was found in oocytes after IVM (P < 0.001 and P < 0.05, respectively). Confocal microscopic observations revealed a significant increase of Cdk4 protein expression in the cytoplasm of oocytes during the maturation process. The localisation of Cx43 changed from zona pellucida before to cytoplasm of oocytes after IVM. It is supposed that the increased expression of Cdk4 and Cx43 mRNA in oocytes after IVM is linked with the accumulation of a large amount of templates during the process of oocyte maturation. The translocation especially of Cx43 from the zona pellucida into the cytoplasm may be associated with a decrease in gap junction activity in fully grown porcine oocytes. Both Cdk4 and Cx43 can be used as ‘checkpoints’ of oocyte maturation

The legal aspects of pregnant cows slaughter

Slaughter of pregnant cows is a very controversial issue. In many countries there are no legislative regulations that definitely prohibit slaughter of pregnant females, in others, the regulations limiting their transportation are ineffective. There are also no regulations concerning their fetuses, mainly in the third semester of gestation, that is a very serious issue of animal welfare. Many animal welfare organizations and humane slaughter associations are involved in improving the welfare of livestock during transport and slaughter and they also offer advice to governments and industry to achieve highest worldwide standards in food animal welfare. However, their efforts too often remain unrecognized. The aim of this article was to present the current, available regulations concerning these very important issues

Contemporary Knowledge on the Assessment of Temperament in Cattle and Its Impact on Production and Reproduction Including Some Immunological, Genetic and Metabolic Parameters

Temperament is associated with the well-being, health, production and reproduction of cattle. In order to increase the population of individuals with the desired temperament, its evaluation should be standardized and be made one of the obligatory elements of breeding and veterinary examination. A number of different tests are used for temperament assessment. In this article, the importance of temperament correlation with some metabolic, genetic, immunological, production and reproductive parameters have been shown, pointing at its influence on the economy and cattle handling. The most common methods for assessing the temperament of cattle are presented, including long-time scales of temperament assessment. At the same time, the relationship of the temperament of cattle with production efficiency, immunity and reproductive indicators has been shown, indicating that its correct assessment is an important aspect of the proper development of the herd and the associated economic growth

Resynchronisation as an element of improving cattle reproduction efficiency

Oestrus resynchronisation (RES, Resynch) programmes for non-pregnant cows allow shortening the period between an unsuccessful insemination and the next attempt on the same cow. The protocol of oestrus RES may be started after ruling out pregnancy by means of ultrasonography carried out 28 days after insemination or after performing a test for pregnancy-specific glycoproteins (PAG) in blood or milk. The Resynch protocol can be based on a double application of prostaglandins, the OvSynch protocol, or hormonal therapy with exogenous sources of progesterone (CIDR intravaginal devices). The efficiency of the method depends on the functional state of the ovaries, the diameter of the corpus luteum, external factors, and the health and maturity of the cows. The present paper constitutes a comparison of research findings concerning the effectiveness of RES programmes

The influence of transfer gun passage time through the uterine cervix on pregnancy rate in recipient heifers

The influence of passage time of the transfer gun through the uterine cervix and body to the embryo insertion site on pregnancy rate was analysed in 248 recipient heifers (mean age: 15–17 months). Embryos (90 fresh and/or 88 and 70 frozen in glycerol and ethylene glycol, respectively, grades 4 and 5, stage 1 or 2) were transferred to the ipsilateral uterine horn on day 7. Two different transfer guns were used in this experiment: a sterilisable steel transfer instrument to be used without sheaths with a removable tip made of gold-plated stainless steel (Wörrlein Minitüb) or a transfer stylet with sheaths with a metal tip and a side opening (Cassou gun, IMV Technologies). The time of passage of the instruments through the uterine cervix and body to the site of embryo deposition in the uterine horn was measured in the study. In order to randomise the risk of errors, all manipulations were carried out by the same experienced operator. The average time needed for the insertion of embryos into the uterus was 50.6 seconds (s) and it was longer for the transfer gun with sheaths than for the metal-tipped transfer gun (60.1 and 40.8 s, respectively) (P 120 s − 28.0, 6.0 and 24.9%, respectively). Thus, it cannot be excluded that the type of the applied transfer gun may influence pregnancy rate in recipient cows due to its effect on cervical passage time

A Critical Overview on Prostaglandin Inhibitors and Their Influence on Pregnancy Results after Insemination and Embryo Transfer in Cows

Assisted reproductive techniques in cattle, such as artificial insemination (AI) and embryo transfer (ET), are widely used. Despite many years of methodological improvements, the pregnancy rate (PR) in cows has not increased in direct proportion with their development. Among the possibilities to increase the PR is the use of certain steroids and nonsteroidal anti-inflammatory drugs (NSAIDs). The antiluteolytic effect of NSAIDs is achieved by blocking cyclooxygenase, which is involved in the conversion of arachidonic acid to prostaglandins. This article compares the PRs obtained after treatment with the commonly used NSAIDs in cattle, including flunixin meglumine, carprofen, meloxicam, ibuprofen, aspirin, and sildenafil. Studies on the effectiveness of certain steroid drugs on the PR have also been described. The results were not always consistent, and so comparisons between studies were made. In conclusion, flunixin meglumine seems to be an option, and can be recommended for improving ET results, especially in situations of high exposure or susceptibility to stress. Its administration under all circumstances, however, might be pointless and will not lead to the desired effect

Congenital sternal ectopia cordis in a Limousin calf – a case report

Recognition and detailed description of malformations and aberrations in domestic animals may be very useful in cognition of the problem and in creating breeding programs. The aim of this study was to describe a rare case of sternal (pectoral) ectopia cordis in a calf. A female calf of the Limousin breed born in Poland in 2011 was subjected to euthanasia because the heart was situated outside the chest. The carcass of the calf was subjected to anatomical examination in which alterations in cardiovascular system and in the structure of the sternum were observed. Cytogenetic studies were performed to find out if the karyotype of the calf was normal. Elongation of the ascending aorta was observed and the pattern of aortic branching was aberrant similarly to that found in dogs, not cattle. The systemic circulation was found to be linked to pulmonary circulation due to persisting large calibre arterial duct. Each of the ventricles had its own cardiac apex and walls of the ventricles manifested a similar width. The atria were slightly altered. A single, short and dilated blood vessel (pulmonary vein) evacuated its content to the left atrium. Pericardium formed no pericardial sac. Radiogram of the sternum demonstrated a ring-resembling shape and 12 (6 pairs) cartilaginous bars of the sternum (sternebrae). A normal female karytotype (60, XX) indicated that this malformation was not caused by an abnormal number of chromosomes (aneuploidy)