Cervimetry and ultrasonographic observations of the cervix regression in dairy cows during the first 10 days post partum

The aim of this study was to describe the involution process of the bovine cervix during the first 10 days post partum by using an intracervically introduced gauge and transrectal ultrasonography. Twenty-five pluriparous Holstein Friesian cows were included, which were randomized into three groups: group 1 (n = 10): transrectal ultrasonographic presentation of the formation of cervical folds; group 2 (n = 10): measurement of the reduction of the canalis cervicalis using an intracervically introduced gauge. The examinations were performed directly after expulsion and 2, 4, 6, 8, 12, 16, 18 and 24 h post partum, and in intervals of 24 h up to the tenth day. The involution process can be divided into four phases: 1: fast reduction up to the sixth hour; 2: protracted reduction up to the second day without constant formation of folds; 3: protracted reduction up to the seventh day with constant formation of folds; 4: re-opening of the canalis cervicalis maintaining the structure of the folds. The reduction process (phase 1- phase 3) can be shown as the sum of two exponential functions with different grading coefficients: y = reduction 1 x e(-b1 x t) + reduction 2 x e(-b2 x t). Reduction 1 is reduction in cm during the first phase and reduction 2 is reduction in cm during the second and the third phase. Group 3 (n = 5): to exclude an influence of the high frequency of examinations on the involution process the cows were examined immediately after parturition and on the fifth and tenth day postpartum using the same method as in groups 1 and 2. In conclusion, the involution process of the bovine cervix guarantees a fast protection of the cavum uteri and a drainage of the lochia at the end of the early puerperium. The re-opening phase after the seventh day has not yet been described in any other species and can be interpreted as the adaptation to the exsudative puerperium in the cow.     

Microscopic anatomy of the lower respiratory tract of the grey short-tailed opossum (Monodelphis domestica)

The respiratory tracts of seven grey short-tailed opossums were histologically examined. Six opossums were prepared by perfusion with buffered formalin. Opossum seven was perfused with gluteraldehyde. Samples taken from the respiratory passages and lungs of specimens 1-6 were stained with haematoxylin and eosin. A mixture of methylene and azure blue was used for specimen 7. The trachea and right and left principal bronchi are lined with a pseudostratified ciliated columnar epithelium with occasional goblet cells. The secondary and tertiary bronchi and the primary and secondary bronchioles are lined by a simple ciliated columnar epithelium. The terminal bronchioles and a portion of the respiratory bronchioles are lined by a simple ciliated cuboidal epithelium. The terminal portion of the respiratory bronchioles and the alveolar ducts are lined with simple squamous epithelium. Alveoli are lined by type I and II pneumocytes. Tracheal glands are present in the tela submucosa. The fibromusculocartilaginous tunic of the trachea consists of c-shaped cartilage rings and the trachealis muscle. A lamina muscularis mucosa begins in the intrapulmonary portion of the principal bronchus and continues into the respiratory bronchioles. Bronchial glands are present in the propria submucosa and tela submucosa of the principal bronchi. The musculocartilaginous tunic is localized to the extrapulmonary portion of the principal bronchus. The bronchial cartilages are irregular shaped plates and limited to the extrapulmonary portion of the principal bronchus. The visceral pleura is a simple squamous mesothelium covering the outer surface of the lung.     

Diseases in neonatal foals. Part 1: The 30 day incidence of disease and the effect of prophylactic antimicrobial drug treatment during the first three days post partum

Reasons for performing study: Neonatal diseases have been grouped and analysed but up‐to‐date statistically significant information about the incidence and prevalence of diseases in foals is limited. Since the 1950s it has been a common management practice to administer a 3 day course of antimicrobial drugs to neonatal foals. This was shown to significantly reduce the incidence of infections (Platt 1977). Since then management practices have improved and it is widely believed that prophylactic antimicrobial drugs are no longer necessary in foal rearing. Objectives: To determine the 30 day incidences or prevalences (depending on case definition) of various diseases and conditions in the neonatal foal and ascertain the influence of a prophylactic 3 day treatment on the frequency of infections. Methods: The population consisted of Thoroughbred foals born on stud farms in the Newmarket (UK) area in 2005 (n = 1031). Depending on the stud farm's practice in the use of prophylactic antimicrobial drugs, 2 groups of newborn foals (treated and untreated) were identified and followed for 30 days. Results: The 30 day incidences of infectious diseases under study were between 0.2% (osteomyelitis) and 5.85% (systemic disease with diarrhoea). The overall incidence for ‘total infectious diseases’ was 8.27%. The most commonly observed noninfectious condition was limb deformities (12.11% of all foals). There was no significant difference in the incidence of infectious diseases between the 2 groups. Conclusion: Infectious diseases are still an important problem in neonatal foals requiring further investigation as to which factors other than antimicrobial prophylaxis are relevant for disease prevention. Potential relevance: The results provide an up‐to‐date overview about the frequencies of various neonatal foal diseases. They do not support the traditional prophylactic use of antimicrobials to prevent infectious diseases in healthy newborn foals. However, it should be noted that this study was not a randomised controlled trial and therefore does not provide the strongest possible evidence for this conclusion.     

The incidence of cervical dystocia and disorders of cervical involution in the post partum cow

The aim of this study was to obtain information on the frequency of cervical dystocia and involution disorders of the canalis cervicalis after difficult dystocia and to characterise factors possibly influencing these pathological conditions. Therefore 317 difficult births in the cow (extraction: 123; foetotomy: 82; caesarean section: 112) and the involution of the cervical canal were documented during the first ten days post partum. In total a cervical dystocia could be diagnosed 53 times (16.7% related to the total number of births). This kind of birth disorder is regularly followed by a caesarean section (p < 0.001). Animals who show a narrowness in the cervix were older than the cows without cervical dystocia (p < 0.05). The same correlation could be detected for the number of births. Animals with delivery problems associated with the cervix had already given birth to more calves than cows who were not affected by cervical disorders (p < 0.01). 58 cows developed a disorder of the cervical involution (18.3% related to the total number of deliveries). This puerperal disorder can be frequently observed after foetotomy (p < 0.001). A correlation between the incidence of disorders of cervical involution and the age or the parity of the animals could not be detected. In the same way, cows with a diagnosis of a cervical dystocia did not develop more frequently disorders of cervical involution than animals who showed a physiological dilation of the cervical canal intra partum.     

Regulation of ovarian function in the post partum cow: an endocrine model

Recent studies of endocrine function during the period after parturition are discussed and used as a basis for the development of a hypothetical model for the control of ovarian function in the cow after calving. It is postulated that the main sequence of endocrine changes is as follows. At first gonadotrophin releasing hormone is secreted infrequently in small quantities. Very early after parturition the secretion of follicle stimulating hormone increases, thus stimulating the development of follicles. There is then a gradual increase in responsiveness to gonadotrophin releasing hormone which results in an increased frequency of release of pulses of luteinising hormone. Follicular growth results in the production of oestradiol and inhibin. Finally there is a gradual restoration of the positive feedback mechanism by which preovulatory gonadotrophin release occurs. In a normal cow the whole process appears to be complete by approximately two weeks after parturition.     

Diseases in neonatal foals. Part 2: Potential risk factors for a higher incidence of infectious diseases during the first 30 days post partum

Reason for performing study: The development of clinical illness in foals is usually predetermined by perinatal history, management or stressful environmental conditions. Objectives: To determine potential risk factors for an increased incidence of infectious diseases during the first 30 days post partum. Methods: The population consisted of Thoroughbred foals born on stud farms in the Newmarket (UK) area in 2005 (n = 1031). They were followed for their first 30 days. Factors suspected to influence the incidence of infectious neonatal diseases were examined in a logistic regression approach for each of the 3 outcomes (total infectious diseases, systemic disease with diarrhoea and total infectious diseases excluding diarrhoea). All 28 factors were either foal or mare or stud farm related. Results: Several significant risk factors for a higher disease incidence, such as birth complications, colostrum intake by stomach tube and leucocytosis 12–48 h post partum were identified. The factor ‘boarding stud’ seemed to be protective against disease. Conclusion: Some factors, such as the mare's time at stud before foaling, the mare's rotavirus vaccination schedule and fibrinogen‐values that empirically had been linked to the outcome previously were not confirmed as relevant. This included the reported useful prophylactic treatment with antimicrobial drugs. Potential relevance: Factors to be considered when evaluating newborn foals include: stud management, the birth process, route of colostrum intake, white and red blood cells, and the date of birth. These may help to detect foals at risk to develop an infection so that targeted prophylactic measures can be initiated.     

The effect of protein source in late pregnancy feed on the occurrence of agalactia post partum in the sow

The effect of an all vegetable protein diet on the occurrence of agalacatia was studied. The experiment was performed in a commercial one thousand sow unit with an average frequency of agalactia of 50%. The all vegetable diet significantly reduced the rectal temperature 48 h post partum and the number of medical treatments required. The litter size at weaning was larger (p greater than 0.05) in the group on the all vegetable protein diet.     

Vaginal cytology studies on the determination of the onset of estrus cycle post partum in sheep]

State of vaginal cells and arborisation grade of cervical mucus were studied in 364 Merino ewes of meat type from the 7. day ante partum. The Pundel modified Shorr-straining method and the Papanicolaou-straining method were used for differentiation of the cells (casal-, parabasal-, intermediate-and superficialcells). Near the 44., 54. and 70. day post partum a maximum of superficialcells and simultaneously a high grade of cervical mucus arborisation in elongating cyclic intervals can be observed in lactating ewes. In conclusion an early weaning of lambs between the 40. and 50. day post partum is considered to be in aggreement with cyclus.     

Plasma levels of cortisol in zero-weaned and lactating sows during the first two weeks post partum

The object of this investigation was to study the plasma levels of cortisol during the day of parturition and the first two weeks post partum in primiparous zero-weaned (weaned within 12 hr after birth) and lactating sows. Fourteen primiparous sows were used. They were grouped as follows: group A, (3 sows) zero-weaned, ovulating; group B, (4 sows) zero-weaned, anovulatory; group C, (4 sows) lactating with normal litter size; group D, (3 sows) lactating with small litter size. The peripheral plasma levels of cortisol were determined by radioimmunoassay throughout the experimental period,The peripheral plasma levels of cortisol were significantly higher in the anovulatory than in the normally ovulating sows. The lactating sows had almost the same levels of cortisol as the zero-weaned sows with anovulatory estrus. There was no difference in cortisol levels between sows nursing small or normal litters.It may be concluded that elevated plasma levels of cortisol might be one of several factors inhibiting the LH surge during the first estrus after zero-weaning. No relationship was found between cortisol levels and number of suckling piglets.     

Incidence of ovarian dysfunction in post partum dairy cows and the effectiveness of its clinical diagnosis and treatment

Ovarian function was assessed from milk progesterone profiles in 236 cows that were presented for clinical examination after parturition and in 227 unexamined herdmates. By 30 days after calving, 81 per cent of the cows had ovulated and by 42 days 92 per cent had resumed cycling. On average milk samples were taken for 155 days, and during this period 67 luteal cysts or cystic corpora lutea and 24 follicular cysts were recorded, and 88 cows were anoestrus for more than 30 days. Luteal cysts, follicular cysts and prolonged anoestrus all occurred twice as frequently in the cows which were clinically examined as in those which were not examined. Progesterone profiles indicated that at the time of clinical examination 72.4 per cent of the cows examined were cycling normally, 11.3 per cent were anoestrus, 6.7 per cent had follicular cysts, 8.0 per cent had luteal cysts and 1.6 per cent were pregnant. Rectal palpation correctly identified ovarian function in only 63.5 per cent of examinations, with 29.8 per cent of cows that were cycling normally, 58.1 per cent that were anoestrus, 70.3 per cent with follicular cysts and 25 per cent with luteal cysts being incorrectly diagnosed. Progesterone profiles confirmed normal oestrous cyclicity in 81.9 per cent of these cows diagnosed as cycling normally by the clinician. The clinical treatments administered included prostaglandin, gonadotrophin-releasing hormone (GnRH), progesterone (PRID) and the physical expression of ovarian structures. Cows diagnosed as cycling normally were left untreated. At the time of treatment, 28.8 per cent of prostaglandin-treated cows had low progesterone concentrations indicating that no luteal tissue was present.(ABSTRACT TRUNCATED AT 250 WORDS)     

Influence of Oligolysis on the development of Musca domestica in manure

The effect of electrochemical treatment of liquid manure (oligolysis) on the development of Musca domestica was studied under laboratory conditions. In electrochemical treated manure clearly fewer flies, pupae and larvae were found compared to untreated manure which was primarily the result of destruction of the surface layer on the treated manure. Furthermore our results suggest that the development of larvae and pupae is inhibited during the electrochemical treatment of manure.     

Embryonic development in the ostrich (Struthio camelus) during the first 7 days of artificial incubation

1. Early development of ostrich embryos was investigated in relation to time of egg collection and genotype.

2. A total of 321 ostrich eggs were collected during the 2008 and 2009 breeding seasons and the development of the embryo for up to the first 168 h of incubation was described and analysed. A sample of the incubated eggs was weighed and opened daily to investigate developmental changes.

3. In fresh eggs, the blastoderm contained a round, translucent dark area pellucida (AP) in the centre, with a surrounding thin white ring, likely to be the beginning of the area opaca (AO). Fresh eggs were considered infertile if the blastoderm was absent and instead numerous white droplets were present surrounded by vacuoles.

4. The average blastoderm area of a fresh fertile egg was 15.8 mm², increasing to 143.3 mm² after 2 d of incubation. By 72 h of incubation the area vasculosa (AV) was discernible in the posterior half of the blastoderm.

5. At 48 h of incubation the blastoderm area in eggs from the South African Black genotype (SAB) × Zimbabwean Blue genotype (ZB) crosses (104.5 ± 18.6 mm²) was lower than the pure SAB (141.0 ± 10.5 mm²), ZB (161.7 ± 13.5 mm²) and ZB × SAB crosses (166.1 ± 14.2 mm²).

6. Embryo length was 5.01 mm after 72 h of incubation and 14.5 mm after 168 h of incubation. At 168 h of incubation AV lengths for both ZB × SAB (53.2 mm) and SAB × ZB crosses (54.1 mm) were longer than in embryos from the pure breeds.

7. Results from this study can be put to practical use when determining whether eggs are infertile or fertile and also in investigating the age of early embryonic mortalities.     

The effects of a post partum injection of prostaglandin F2 alpha on return to oestrus and pregnancy rates in dairy cows

The interval from calving to conception is unnecessarily long in dairy cows. Post partum administration of prostaglandin F2 alpha can reduce the calving to conception interval, but it is not known whether this is due to advanced return to oestrus, increased oestrus intensity and/or increased pregnancy rates. In two experiments, the treatment of dairy cows with prostaglandin F2 alpha 21 days post partum reduced the interval to first oestrus and first service by about 10 days. The intensity of oestrus was not affected. Pregnancy rates to first service were increased from (on average) 60 to 80%, and the number of services/conception was reduced from 2.0 to 1.3.