Colostrum yield and litter performance in multiparous sows subjected to farrowing induction

The consumption of colostrum at a low level can compromise the survival and growth of piglets. Therefore, this study aimed to evaluate the effect of farrowing induction on colostrum yield, IgG concentration and the survival and performance of piglets until the weaning. Sows of parity 3 to 7 were assigned into two groups: Control (n = 48), sows with spontaneous farrowing; and induction (n = 48), sows induced to farrow on day 114 of gestation with a PGF₂ analogue. Colostrum and blood samples were collected from the sows, at farrowing and 24 hr later. Blood samples from the piglets were collected at 24 hr after birth. The performance of the piglets was evaluated in a subsample of 28 litters from each group. All piglets were weighed at 7, 14 and 20 days of age. The farrowing length, the number of piglets born alive, stillborn piglets, weight at birth, litter weight at birth and colostrum yield were not significantly affected (p > .05) by farrowing induction. There was no difference between the groups (p > .05) in the percentage of sows with obstetric interventions. Serum IgG concentration, in both sows and piglets, and colostrum IgG concentration were similar between the groups (p > .05). Furthermore, survival rate, piglet weight and litter weight at 7, 14 and 20 days of age were also similar between the groups (p > .05). Therefore, it can be concluded that the farrowing induction performed on day 114 of gestation does not affect the colostrum yield, the IgG concentration in colostrum and serum of piglets, and the litter performance until the weaning.     

Endometrial gene expression in primiparous dairy cows at the end of the voluntary waiting period is affected by nutrition: Total mixed ration vs increasing levels of herbage allowance

The study postulated that differential nutritional management during the early lactation period would be reflected in endometrial expression of genes related to embryo growth at the end of the voluntary waiting period. Thus, the effect of the combined use of total mixed ration (TMR) and grazing under different herbage allowances during the first 75 days post‐partum (DPP) on endometrial gene expression was evaluated in primiparous dairy cows. Cows were blocked by body weight, age and body condition score and randomly assigned to three grazing treatments: high (HA, 30 kg DM per cow per day), medium (MA, 15 kg DM per cow per day) and low (LA, 7.5 kg DM per cow per day) herbage allowance (mixed pasture, 2,600 kg DM per ha) plus 8 kg DM of supplement or TMR (55% forage, 45% concentrate) fed ad libitum (TMR) from calving to 75 DPP. At 57 DPP, cows were synchronized for oestrus (day 0, 68 DPP) and at day 7, endometrial biopsies were obtained. The nutritional treatment did not affect insulin, IGF‐1 and leptin concentrations on days 0, 4 or 7. Expression of IGF1, IGFBP3, IGFBP4, ADIPOR1 and ADIPOR2 mRNA was significantly affected by the nutritional treatment. Endometrial IGF1 and IGFBP4 mRNA were twofold greater in TMR and HA than MA and LA cows. Expression of IGFBP3 and ADIPOR1 mRNAs was greater in TMR and HA than MA cows, but did not differ from LA cows. All groups had greater expression of ADIPOR2 mRNA than MA cows. This study provided solid evidence of the importance of nutritional management during early lactation on uterine environment at the end of the voluntary waiting period. The greater expression of genes related to embryo growth and uterine function (IGF system, progesterone and adiponectin receptors) in cows fed diets maximizing energy intake suggests a favourable environment for embryonic growth, which may explain the improved reproductive performance of cows in good energy balance.     

Elevation of plasma cholecystokinin concentration following a meal is increased by gonadectomy in male cats

An overweight or obese body condition commonly develops after gonadectomy (GX) in domestic cats. The cause appears to be a rapid, quantal (approximately 12%), increase in food intake that is sustained and probably mediated by withdrawal of gonadal hormone. Recently, an interaction of gonadal hormone and cholecystokinin (CCK) effectiveness has been suggested. A reduction in the satiating potency of intestinal CCK was presently hypothesized to contribute to the disturbance of food intake control caused by GX in domestic cats. Pre- and post-prandial intestinal CCK secretion as indicated by plasma CCK concentrations were determined in 16 adult male cats (5.1 +/- 0.1 kg) 8 weeks before and 57 weeks after eight of the cats were gonadectomized. During ad libitum intake of a commercial dry, expanded diet, body weight increased from 22% to 28% in gonadectomized cats and was unchanged in intact cats. Baseline CCK concentrations were not different between gonadectomized and intact cats. Amounts of diet ingested during CCK determinations were 15-19% of daily metabolizable energy requirement and were not different between gonadectomized and intact cats. The post-prandial area under the curve (AUC; 0-400 min) CCK concentration increased linearly with meal size (p < 0.01) and was not correlated with body weight. Area under the curve CCK concentration, when normalized for meal size, was 34% greater (p < 0.01) in gonadectomized cats than that in intact cats. The findings indicate GX increases meal-induced intestinal CCK secretion and therefore, do not support the study hypothesis. The findings indicate GX may slow digestion and absorption and attenuate inhibition of food intake by CCK.     

Haematological, biochemical and selected acute phase protein reference intervals for weaned female Merino lambs

Background   Merino lambs are currently the subject of much research into the welfare aspects of mulesing and mulesing alternatives.
Objective   Obtain haematology, biochemistry and acute phase protein reference intervals using modern methodologies for female Merino lambs.
Method   Blood was collected from 50, weaned, 9- to 16-week-old, female Merino lambs. Haematology and biochemistry panels were performed using routine automated methods. The acute phase proteins, fibrinogen, serum amyloid A and haptoglobin, were also measured using commercially available techniques. The reference intervals were determined to be the central 95% of results.
Results   Differences in the concentrations for some analytes were seen when compared with reported studies in sheep, but may be explained by the use of sheep of a different signalment, as well as different methodologies for analyte measurement. Overall, most analytes gave similar values to those previously reported in other studies. Notable exceptions were alkaline phosphatase, phosphate and globulins, for which the different results were often attributed to the younger age of the sheep in the present study, and platelets and creatine kinase, for which the elevated levels may have been a result of stress and muscle exertion associated with blood collection and husbandry practices.
Conclusion   Established haematological, biochemical and acute phase protein reference intervals are necessary for the investigation of the systemic impact of mulesing and mulesing alternatives and for the investigation of systemic diseases affecting weaned, 9- to 16-week-old, female Merino lambs in general.     

Influence of Sperm Cell Dose and Post-insemination Backflow on Reproductive Performance of Intrauterine Inseminated Sows

This study was carried out to evaluate the effects of the sperm cell dose and semen backflow on the pregnancy rate and number of embryos of sows inseminated once at 0-24 h before ovulation, using an intrauterine technique. The results were analysed from a total of 211 sows assigned to three groups inseminated with doses of 0.25 x 10(9) (T1), 0.5 x 10(9) (T2) and 1.0 x 10(9) (T3) spermatozoa. Semen backflow was observed in 95% of the females (143/151) evaluated for this purpose. The percentage of semen backflow is close to two-third of the volume and the percentage of sperm is around 15% of the infused sperm dose. Intrauterine insemination can be successfully performed provided that at least 0.5 billion of sperm cell dose is infused at an interval of 0-24 h before ovulation.     

In vitro Release of Ovarian Progesterone is Decreased During the Oestrous Cycle and Pregnancy of Swine with Obesity/Leptin Resistance

Previous studies indicate that reproductive prolificacy of obese swine breeds is markedly influenced by embryo losses in early pregnancy. In such period, adequate secretion of progesterone (P4) by the ovary is essential for pregnancy success. This study analyses the luteal functionality during the oestrous cycle and early pregnancy of Iberian sows and Large White x Landrace females, in terms of P4 secretion after in vitro culture of luteal tissue stimulated or not with luteinizing hormone (LH). The secretion of progesterone (expressed in ng/mg of luteal tissue or ng/mgLT) of the corpora lutea of obese Iberian swine was always hampered when compared to lean genotypes, either during early oestrous cycle (110.7 ± 37.8 vs 259.7 ± 10.2 ng/mgLT; p < 0.0001), late oestrous cycle (49.0 ± 3.5 vs 75.92 ± 7.14 ng/mgLT; p < 0.0001) or early pregnancy (38.4 ± 2.1 vs 70.7 ± 5.3 ng/mgLT; p < 0.0001). The differences in basal P4 secretion remained after stimulation with LH. Finally, P4 secretion during early pregnancy of Iberian sows decreased with age and, hence, with obesity features (46.6 ± 4.2 vs 65.5 ± 4.8 ng/mgLT; p < 0.001). In conclusion, the results of the present study provide convincing evidence of a reduced luteal function during oestrous cycle and early pregnancy of sows with obesity/leptin resistance like Iberian sows, which may contribute to the low reproductive efficiency reported in this breed.