Nutritional management of multiple pregnancies.

Good nutrition is central to achieving optimal fetal growth and development, and to maintaining maternal health and wellbeing. For multiple pregnancies, there is a growing body of evidence linking good maternal nutrition and weight gain to positive perinatal outcomes including reduced incidence of low birthweight and very low birthweight infants. Nutrition intervention appears to have important clinical implications for infant morbidity and mortality. Nutritional counselling can help women improve and maximise their intake of "at risk nutrients" such as iron, folate, essential fatty acids, calcium and ensure adequate energy intake to meet weight gain targets. Recommended optimal weight gains range from 16-20 kg for twin pregnancies. Expert dietetic guidance is often warranted, especially for women expecting triplets or quadruplets.     

Nutritional investigations and management of captive moose

Historically, moose have been difficult to maintain in captivity when on diets of grass or legume hays and grain due to enteritis that frequently leads to chronic diarrhea/wasting disease. The development of wood-fiber diets has increased the lifespan of moose in captivity, but these diets do not completely prevent chronic wasting. Purina Mills (St. Louis, MO) hypothesized that captive moose are unable to digest starch that escapes the rumen, and therefore abnormal bacterial fermentation in the hindgut causes chronic diarrhea. An earlier study found no evidence of a digestive problem, so we tested the hypothesis that moose have difficulty metabolizing excess propionate produced from the fermentation of starch found in traditional cervid rations and high-grain wood-fiber diets. When challenged with an i.v. propionate load, moose metabolized propionate similar to healthy mule deer and domestic livestock. We then tested the hypothesis that grass forage is an initiating factor to chronic diarrhea/wasting and further hypothesized that grass, alfalfa, and other agriculture-based forages in association with an anaerobic bacteria produce inflammatory bowel disease (IBD) in moose. Captive moose that had ad libitum access to a wood-fiber pelleted moose diet and grazed in grass pastures developed chronic wasting symptoms at 2–4 years of age and died at 4.7 ± 0.3 years unless restricted from grass before the development of advanced symptoms. We isolated Bacteroides vulgatus in the feces and successfully treated a moose with chronic diarrhea/wasting disease with long-term metronidazole therapy, suggesting that the chronic enteritis causing wasting disease arises from a bacteria-associated defective immunosuppressive response similar to IBD in other species. Further support for the IBD cause of wasting in moose is that this animal will relapse within hours if the metronidazole treatment is discontinued even after many months. We developed a highly palatable high-fiber, low-starch moose ration that can be fed as the sole source of nourishment, although additional research and dietary improvements are required. Zoo Biol 16:479–494, 1997. © 1997 Wiley-Liss, Inc.     

The effect of nutritional management of the dairy cow on reproductive efficiency

The cause of low fertility in dairy cows is multifactorial. Poor nutrition during the dry and early postpartum periods results in reduced glucose, insulin, insulin-like growth factor (IGF-I) and low LH pulse frequency with concomitant increases in beta-hydroxy butyrate, non-esterified fatty acids (NEFA) and triacylglycerol. Cows must mobilize large lipid, but also some protein reserves, with a consequent increased incidence of such metabolic disorders as hypocalcaemia, acidosis, ketosis, fatty liver and displaced abomasums. The occurrence of milk fever and ketosis affects uterine contractions, delays calving and increases the risk of retained foetal membranes (RFM) and endometritis. The nutritional risk factors that cause RFM are hypocalcaemia, high body condition score (BCS) at calving and deficiencies in Vitamin E and selenium. The risk factors for endometritis are hypocalcaemia, RFM, high triacylglycerol and NEFA. Thus, metabolic disorders predispose cows to gynaecological disorders, thereby reducing reproductive efficiency. Cows that are overconditioned at calving or those that lose excess body weight are more likely to have a prolonged interval to first oestrus, thereby prolonging days open. Nutritionally induced postpartum anoestrus is characterized by turnover of dominant follicles incapable of producing sufficient oestradiol to induce ovulation due to reduced LH pulse frequency. High nutrition can also increase metabolic clearance rate of steroid hormones such as progesterone or oestradiol. Lower concentrations of oestradiol on the day of oestrus are highly correlated with the occurrence of suboestrus, thereby making the detection of oestrus in high yielding cows even more difficult. Nutrition also affects conception rate (CR) to AI. Cows that develop hypocalcaemia, ketosis, acidosis or displaced abomasums have lower CRs and take longer to become pregnant. Excessive loss of BCS and excess protein content of the ration can reduce CR while supplemental fats that attenuate the production of F2alpha can improve CR. The increased metabolic clearance rate of progesterone (P4), which decreases blood concentrations during early embryo cleavage up to the blastocyst stage is associated with decreased CRs. In conclusion, poor nutritional management of the dairy cow, particularly before and after calving, is a key driver of infertility.     

Retrospective analysis of the management of 78 cases of postpartum metritis in the cow

Case records of post partum metritis in cows were obtained from Auburn University (42 cases) and Tuskegee University (36 cases) Large Animal Hospital files. Dairy cows (n=68) comprised 87.2% of the cases and beef (n=10) 12.8%. Age did not differ between the types, but the number of postpartum days at admission (mean +/- 1 SD) differed significantly (P=0.02) between dairy (7.3 +/- 4.27) and beef (3.7 +/- 4.06) cows. Older cows and those with hyperthermia were less likely to recover from puerperal metritis (P=0.07 and 0.03, respectively). Type of treatment had no significant association with survival. The number of days of hospitalization was associated with institution (P<0.001), number of postpartum days at admission (P=0.001), history of predisposing factors (P=0.0006), hyperthermia (P=0.006), and length of various treatments (P<0.001). However, the type of treatment had no significant association with length of hospitalization. This study suggests that the necessity for or type of therapy has little effect on the outcome of postpartum metritis.     

Integrating fasciolosis control in the dry cow management: the effect of closantel treatment on milk production

The liver fluke Fasciola hepatica is a parasite of ruminants with a worldwide distribution and an apparent increasing incidence in EU member states. Effective control in dairy cattle is hampered by the lack of flukicides with a zero-withdrawal time for milk, leaving the dry period as the only time that preventive treatment can be applied. Here, we present the results of a blinded, randomized and placebo-controlled trial on 11 dairy herds (402 animals) exposed to F. hepatica to 1) assess the effect of closantel treatment at dry-off (or 80-42 days before calving in first-calving heifers) on milk production parameters and 2) evaluate if a number of easy-to-use animal parameters is related to the milk production response after treatment. Closantel treatment resulted in a noticeable decrease of anti-F. hepatica antibody levels from 3-6 months after treatment onwards, a higher peak production (1.06 kg) and a slightly higher persistence (9%) of the lactation, resulting in a 305-day milk production increase of 303 kg. No effects of anthelmintic treatment were found on the average protein and fat content of the milk. Milk production responses after treatment were poor in meagre animals and clinically relevant higher milk production responses were observed in first-lactation animals and in cows with a high (0.3-0.5 optical density ratio (ODR)), but not a very high (≥0.5 ODR) F. hepatica ELISA result on a milk sample from the previous lactation. We conclude that in dairy herds exposed to F. hepatica, flukicide treatment at dry-off is a useful strategy to reduce levels of exposure and increase milk production in the subsequent lactation. Moreover, the results suggest that treatment approaches that only target selected animals within a herd can be developed based on easy-to-use parameters.     

Nutritional management of hypertension: past, present, and future

A succinct overview of the nutritional management of hypertension, past, present, and future is presented. Prior to 1945, the low sodium diet and the rice-fruit diet were shown to be effective in reducing the blood pressure to normal levels in 35-40% of hypertensive patients. Between 1945 and the present, many studies were made on the effects of alcohol, water hardness, obesity, moderate restriction of sodium with increased potassium intake, increased dietary calcium, low animal and high unsaturated fat intake, and increased amounts of fiber in the diet. Criticisms are made of the very small magnitude, even if statistically significant, of blood pressure decreases and the too-short control periods in many instances, and also concerning the assumption of use of 24-h urinary sodium as an accurate index of the sodium intake, and of urinary creatinine as a physiological reference standard against the excretion of sodium. The author mentions, for possible future research, long-term studies of the effects of diets moderately restricted in sodium and high in potassium, of reducing weight and increasing physical activity in obese hypertensives, and of low animal and high polyunsaturated fat diets in patients with mild essential hypertension.     

Timed embryo transfer programs for management of donor and recipient cattle

Currently, timed ovulation induction and fixed-time artificial insemination (FTAI) in superstimulated donors and synchronization protocols for fixed-time embryo transfer (FTET) in recipients can be performed using GnRH or estradiol plus progesterone/progestin (P4)-releasing devices and prostaglandin F_2α (PGF2α). The control of follicular wave emergence and ovulation at predetermined times, without estrus detection, has facilitated donor and recipient management. However, because Bos taurus cows have subtle differences in their reproductive physiology compared with Bos indicus cattle, one cannot assume that similar responses will be achieved. The present review will focus on the importance of orchestrating donor and recipient management to assure better logistics of procedures to achieve more desirable results with embryo collection and transfer. In addition, this will provide clear evidence that the use of FTAI in superstimulated donors and FTET in embryo recipients eliminates the need to detect estrus with satisfactory results. These self-appointed programs reduce labor and animal handling, facilitating the use of embryo transfer in beef and dairy cattle.     

Timed embryo transfer programs for management of donor and recipient cattle

Currently, timed ovulation induction and fixed-time artificial insemination (FTAI) in superstimulated donors and synchronization protocols for fixed-time embryo transfer (FTET) in recipients can be performed using GnRH or estradiol plus progesterone/progestin (P4)-releasing devices and prostaglandin F_2α (PGF2α). The control of follicular wave emergence and ovulation at predetermined times, without estrus detection, has facilitated donor and recipient management. However, because Bos taurus cows have subtle differences in their reproductive physiology compared with Bos indicus cattle, one cannot assume that similar responses will be achieved. The present review will focus on the importance of orchestrating donor and recipient management to assure better logistics of procedures to achieve more desirable results with embryo collection and transfer. In addition, this will provide clear evidence that the use of FTAI in superstimulated donors and FTET in embryo recipients eliminates the need to detect estrus with satisfactory results. These self-appointed programs reduce labor and animal handling, facilitating the use of embryo transfer in beef and dairy cattle.     

A herd health approach to dairy cow nutrition and production diseases of the transition cow

This paper presents a practical, on-farm approach for the monitoring and prevention of production disease in dairy cattle. This integrated approach, should be used in an interdisciplinary way by farmers, veterinarians, nutrition advisors and other relevant professionals for the improvement of animal health and welfare and producer profitability. The key areas that form the basis for this approach are body condition score management, negative energy balance, hypocalcaemia, rumen health and trace element status. Monitoring criteria are described for each of these key areas, which when considered collectively, will facilitate the assessment of dairy cow health with regard to clinical and subclinical disease. The criteria, which are informed by published scientific literature, are based on farm management and environmental factors, clinical data, milk production records, dietary analysis, and assessment of blood and liver concentrations of various metabolites or trace elements. The aim is to review the efficacy of production disease control measures currently in place, and if necessary to modify them or formulate new ones.     

Nutritional influence on fertility in Israeli dairy herds with an average 305-day production per cow of 8000 kg of fat-corrected milk

Fertility and nutritional data from 13 Israeli-Holstein Kibbutz dairy herds, which were milking a total of 3314 cows and heifers, with an average 305-day production of 8,649 Kg of fat-corrected milk, were collected, compared and analyzed.The following fertility data were observed: Overall conception rate (OCR), 39.2%. Retained placenta, 7.65%. Metritis, 5%. Anestrus, 9.9%. Suspected early embryonic resorption, 5.3%. Repeat breeders, 12.2%. Problem cows (not pregnant 150 days postpartum), 22.5%.These herds were divided into two production groups. One group consisted of 8 herds producing 8,000–8,500 Kg. (average 8,253 Kg); and the other group of 5 herds producing 8,900–9,800 Kg (average 9,284 Kg). There was no significant difference in the fertility data obtained from these two groups.A division of these 13 herds into 3 groups based on overall conception rate was made as follows: 4 herds with high OCR, above 45%; 6 herds with medium OCR, 35–41%; and 3 herds with low OCR, less than 31%. There were no significant differences between these 3 groups of herds in percentages of retained placenta, metritis, anestrus and suspected early embryonic resorption. The percentage of repeat breeders was 6.9 in the high group, 9.4 in the medium group and 20.6 in the low group. All three differences were significant. The percentage of problem cows was 16.5%, 22.5%, and 30.6%, respectively. There was a significant difference between the high and low OCR groups.An analysis of the nutritional data showed that in the first half of the lactation period (high production period) there was a significant difference between all 3 groups in the percentage of roughage fed. In the second half of the lactation period the difference in digestible protein fed to the high and low OCR groups was nearing significance. The overall amount of energy fed during this same period was 17.9 Scandinavian Feeding Units (SFU) in the high; 16.7 SFU in the medium, and 15.9 SFU in the low group. None of these differences was statistically significant.     

Indomethacin inhibition of ovulation in the cow

Indomethacin or saline was administered via intramuscular, intrauterine or intraovarian routes to dairy cows, within 24 h after standing oestrus was first observed. The incidence of ovulation was determined at slaughter. All of the saline-treated cows (18/18) ovulated. Ovulation was not blocked after intramuscular injection (0/6) or intrauterine infusion (0/6) of indomethacin. In all cows, ovulation was blocked after intraovarian injection (6/6) of indomethacin. These findings add support to the hypothesis that prostaglandins play an essential role in ovulation in the cow as in many other mammalian species.     

Fetal-maternal secretion of prostaglandins in the cow

A study was conducted to measure the blood plasma concentrations of prostaglandin F₂α (PGF₂α), 13,14-dihydro-15-keto-prostaglandin F (PGFM), 6-keto-prostaglandin F₁α (6-keto), prostaglandin E₂ (PGE₂), and thromboxane B₂ (TBX₂) in the ovarian vein, uterine artery, uterine vein, umbilical artery and umbilical vein in 24 cows from days 80 to 260 of pregnancy. Blood was collected during surgery and all prostaglandins were measured using specific radioimmunoassay procedures. Results indicate that PGF₂α blood levels are higher in the umbilical vessels and uterine vein than in the ovarian vein and uterine artery. PGFM and PGE₂ showed a trend towards higher values in the umbilical than in the maternal vessels, but the levels of 6-keto and TBX₂ were not different among the vessels studied. No differences across time couls be observed in any of the prostaglandins measured, partly due to the great variability in blood levels among animals during the same stage of pregnancy.