The development of the concept of ferroptosis.

Nutrient and immunity transfer from cow to calf pre- and postcalving.

Selenium is linked to male fertility. Glutathione peroxidase 4 (GPx4), first described as an antioxidant enzyme, is the predominant selenoenzyme in testis and has been suspected of being vital for spermatogenesis. Cytosolic, mitochondrial, and nuclear isoforms are all encoded by the same gene. While disruption of entire GPx4 causes early embryonic lethality in mice, inactivation of nuclear GPx4 does not impair embryonic development or fertility. Here, we show that deletion of mitochondrial GPx4 (mGPx4) allows both normal embryogenesis and postnatal development, but causes male infertility. Infertility was associated with impaired sperm quality and severe structural abnormalities in the midpiece of spermatozoa. Knockout sperm display higher protein thiol content and recapitulate features typical of severe selenodeficiency. Interestingly, male infertility induced by mGPx4 depletion could be bypassed by intracytoplasmic sperm injection. We also show for the first time that mGPx4 is the prevailing GPx4 product in male germ cells and that mGPx4 disruption has no effect on proliferation or apoptosis of germinal or somatic tissue. Our study finally establishes that mitochondrial GPx4 confers the vital role of selenium in mammalian male fertility and identifies cytosolic GPx4 as the only GPx4 isoform being essential for embryonic development and apoptosis regulation.

Mitochondrial glutathione peroxidase 4 disruption causes male infertility

This review addresses the concept that essential trace minerals play a vital role in many enzymatic and metabolic pathways that are critical for conceptus development during pregnancy in livestock species. The conceptus relies entirely on the maternal system for a sufficient supply of trace minerals and other nutrients needed for normal development. If this supply is inadequate, growth and/or health of the conceptus can be affected adversely, and many of these effects carry over into the neonatal period. Information, accumulated in our laboratory and presented herein, indicates that zinc, copper and manganese are among the trace minerals that have the greatest impact on reproduction. For example, levels of zinc, copper and manganese were several fold greater in the conceptus than in other reproductive tissues, indicating that the conceptus preferentially accumulates these minerals, an action that may be important for conceptus development, growth and survival. Moreover, some recent results indicate that increasing the biological availability of zinc, copper and manganese, by attachment to short peptide chains (i.e., proteinated trace minerals) can enhance reproductive performance of swine. Mineral concentrations in conceptuses from female pigs consuming proteinated trace minerals were greater than those from females that consumed only inorganic mineral salts. Elucidating the mechanisms whereby conceptus development and survival are enhanced by essential trace minerals may lead to development of specific feeding programs to increase the number and health of offspring at parturition, thereby allowing for further improvements in production efficiency in animal agriculture.

The role of essential trace elements in embryonic and fetal development in livestock.

Effect of dry period overconditioning on subsequent metabolic disorders and performance of dairy cows.

In addition to the classic form of parturient paresis characterized by hypocalcemia and somnolence, which responds rapidly to calcium therapy, it is not unusual to encounter other forms of this disease. The most common aberration would seem to be that in which the animals do not rise after calcium treatment. Many of these cows show little or no drowsiness, their appetite is often good, and the results of a clinical examination often negative. Some authors, Blood & Henderson (1960) for instance, consider that this “downer cow syndrome” is an independant disease not connected wiht milk fever. Although the downer cow syndrome is a common disease and is of considerable significance, remarkably little has been written about it. Garm in 1950 noted that the frequency of downers had increased as compared with the numbers registered a few years earlier. He had also noticed that in many of these cows hypocalcemia was present on the first day of illness but not on subsequent days, despite the fact that they had marked signs of milk fever. Osinga, in an investigation in 1963, compared two types of milk fever: a typical form in which the cow is drowsy, lies on her side, and has partial anorexia, and an atypical form in which the animal is alert and has normal or only slight loss of appetite. Osinga remarked that the atypical cases had in-creased in number and suggested as an explanation the fact that the amount of protein in the fodder has increased, with the result that auto-intoxication and damage to parenchymatous organs may occur. The object of the present investigation was to study the difference between cows that recover after treatment (“uncomplicated milk fever”) and those that have not risen 24 hrs. after the first treatment (“downers”). We also wanted to ascertain whether any changes occurred in the downers between the first and second, and second and third days. In addition, the difference between cows with blood-calcium levels equivalent to or over 8.0 mg/100 ml serum and those with corresponding values under 8.0 mg at the first examination was also studied.

/pdf/studies-on-parturient-paresis-with-special-reference-to-the-eo20szidpn.pdf

Studies on parturient paresis with special reference to the Downer cow syndrome.

The effects of dexamethasone (DM) on peripheral levels of estrogen and progesterone were studied in 8 pregnant cows. 4 cows 248-250 days pregnant received 10 or 20 mg DM intramuscularly followed by a 2nd injection 3-6 days later. 2 cows 75 days pregnant and 2 cows 147-150 days pregnant received 40 mg DM for 7-12 days. All cows in late pregnancy delivered live calves 12-68 hours after the 2nd injection. The cow treated at 150 days of pregnancy aborted on the 6th day of treatment while dead fetuses were found in the remaining cows. In all cows in late pregnancy a peripheral plasma increase in estrone preceded a decrease in progesterone after DM treatment. Decreased plasma levels of progesterone were found in the cow that aborted. There were no marked changes in progesterone levels in the 3 remaining cows. An increase in plasma levels of estrone was not detectable in any of the early or midterm pregnant cows. The hormonal pattern resulting from DM treatment in late pregnant cows seems to mimic the pattern found in normal parturition.

Peripheral plasma levels of oestrone and progesterone in pregnant cows treated with dexamethasone.

Twenty veal calves were fed milk substitute containing 19 mg Fe/kg; ten calves were supplemented with iron in accordance with their requirements and the other 10 were unsupplemented controls. Serum iron (SI), hemoglobin (Hb) and packed cell volume (PCV) were determined at the start of the experiment and then every third week. From 3 weeks after the start to the end of the experiment there were significant differences between SI mean values between treated and untreated calves. In the treated group the Hb mean values were unchanged during the experiment while the untreated group had a significant decrease. The mean PCV values were also decreased. The daily gain was 1.36 g higher per calf in the treated group. The feed consumption per kg gain was 18 g lower and the carcass weight was 4.2 kg higher per calf in the treated group. The points for color and structure of carcass were 2.5 units higher per calf in the untreated group. The incidence of enteritis was less in the treated calves than in the untreated ones.

/pdf/the-effect-of-parenteral-iron-supply-on-hematology-health-537qojsr31.pdf

The effect of parenteral iron supply on hematology, health, growth and meat classification in veal calves.

The distribution in the mouse of Se75 after injection of Se75 sodium selenite was studied by autoradiography of sagittal whole-body sections. The animals were killed at various times, from 5 minutes to 8 days, after a single intravenous injection. The distribution was characterized by a high blood level of selenium during the whole observation period. The highest concentration of selenium soon after the injection was found in the liver, heart, kidney and adrenal cortex. Eight days after the injection the highest concentration was seen in the liver and the kidney. The selenium penetrated the placenta, but the uptake was much lower in the fetuses than in the maternal tissue.

/pdf/distribution-of-selenium-in-mice-studied-by-whole-body-3u16zs3rh5.pdf

Distribution of selenium in mice studied by whole-body autoradiography after injection ff SE-75-sodium selenite.

Determinations of plasma volume were made of 9 clinically healthy Swedish Red and White calves from birth to 90 days of age by means of the isotop dilution technique. Commercially available 131I labelled human serum albumin was used. Calculation of the total blood volume was based on the plasma volume and packed cell volume. The plasma and blood volumes increased per kg body weight in average 17 and 14% respectively from directly after birth to 24 hrs. old. From 1 to 90 days of age the plasma and blood volume fell steadily per kg body weight. Plasma volume expressed as a percentage of body weight was 5.3% at birth, 6.5% at 1 day old, and 4.9% at 90 days old. Corresponding values for blood volume were 8.4, 9.3 and 7.0%.

https://link.springer.com/content/pdf/10.1186/BF03546672.pdf

S. O. Jacobsson

Papers

Studies on parturient paresis with special reference to the Downer cow syndrome.

Peripheral plasma levels of oestrone and progesterone in pregnant cows treated with dexamethasone.

The effect of parenteral iron supply on hematology, health, growth and meat classification in veal calves.

Distribution of selenium in mice studied by whole-body autoradiography after injection ff SE-75-sodium selenite.

Plasma and blood volume in the calf from birth till 90 days of age.