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At least 19 recordsLinked to original sources
PubMed2025

Manipulating seasonality by using PMSG and Kisspeptin hormones and the impact of the MTNR1A gene on reproduction efficiency in ewes.

BACKGROUND: One of the most important problems in sheep is seasonal anestrus, which limits the reproductive efficiency of the sheep. Estrous synchronization is considered the first plan for reproductive performance in sheep due to the pregnancy time is limited, and parturition as well as an increase in twining and reached good genetic characteristics. AIM: This study aimed to manipulate seasonality that limits fertility in ewes by induction estrus during seasonal anestrous in sheep by using Pregnant Mare Serum Gonadotropin (PMSG), Kisspeptin hormone, and study the impact of MTNR1A gene on reproduction efficiency in ewes. METHODS: This study examined 36 Awassi ewes divided into two groups, each containing 18 ewes, 2-3 years old, and two fertile rams aged 3-4 years and weighing 60-65 kg. All non-pregnant ewes were synchronized using vaginal sponges (60 mg Medroxy Progesterone acetate) for 10 days. The injection of treatment when sponges are draws. The first group (G1) received 500 IU of PMSG injection, and the second group (G2) injection a Kisspeptin hormone 5 &#x3bc;g/kg B.W. RESULTS: The results showed the G1 treated by PMSG 500IU were higher significantly (p &#x2264; 0.05) of estrus response, induction estrus and pregnancy (89%, 89%, and 89%), respectively, comparative with G2 treated by (Kisspeptin 5 mg/kg) were (72%, 72%, and 66%), respectively, and non-significant changes in estrus were observed in all groups. The average peripheral progesterone concentration significantly increased from day 0 to 5th month in G1 comparative with G2 in pregnant ewes. Serum progesterone levels were significantly p < 0.05 during of 4th month in G1 treatment by (PMSG 500IU) compared with day 0 and all other months during pregnancy of ewes. The average days to lambing in genotypes CT and TT (150 &#xb1; 2.5 and 152 &#xb1; 3.5 days), respectively, were significant comparative with CC genotype; however, the litter size and lambing rate observed in the enrolled ewes were non-significant in all genotypes. CC, CT, and TT represent three possible genotypes at a specific location (locus) in the genome, often referring to a single nucleotide polymorphism (SNP). These genotypes indicate the combination of alleles an individual inherits from their parents for a particular gene. They refer to the presence of two alleles for a particular nitrogenous base: C and T are nitrogenous bases: C = Cytosine and T = Thymine. CONCLUSION: In conclusion, the application of PMSG and Kisspeptin was effective in achievement good higher significantly of reproduction efficiency in this study. The genotypes CT and TT of the MTNR1A gene polymorphism were connected with a short significant of days to lambing in genotypes.

Animals↗
PubMed1977

Effects of thin ewe syndrome on reproductive efficiency.

A debilitating condition affecting mature ewes was found to be associated with the visceral form of caseous lymphadenitis, chronic progressive pneumonia, and Corynebacterium pyogenes infections. The condition was termed thin ewe syndrome. Affected and normal ewes were compared for reproductive efficiency by breed and age; differences in reproductive efficiency between affected and normal Rambouillet and Columbia ewes were highly significant (P less than 0.01). Although not statistically significant, the trend in Targh ee ewes was similar. There was a direct correlation between occurence of the syndrome and increasing age for all breeds.

Animals↗
PubMed1975

Survey of reproductive efficiency in the Quarter-horse and Thoroughbred.

Reproductive efficiency was evaluated for 838 Quarter-horse mare-years on five farms and 939 Thoroughbred mare-years on seven farms over 4 years. The pregnancy rate from first service was 51% for Quarter-horse mares and 43% for Thoroughbred mares (P less than 0-05). The cumulative pregnancy rate after five services was 85% for Quarter-horse and 77% for Thoroughbred mares (P less than 0-05). First-service-period pregnancy rates were 44, 40 and 54% for maiden, barren and foaling mares, respectively. Cumulative pregnancy rates after five service-periods were 84, 74 and 84% for maiden, barren and foaling mares, respectively. The pregnancy rate for foaling mares served during foal heat was lower (P less than 0-05) than the first-servicd pregnancy rate of foaling mares served after the foal heat. Less than 40% of the maiden mares, less than 50% of the barren mares and less than 30% of the foaling mares were submitted for their first-service-periods by the end of March.

Animals↗
PubMed1977

Breeding record analysis in pig herds and its veterinary applications--1: Development of a program to monitor reproductive efficiency and weaner production.

Analyses of breeding records and herd efficiency factors are important for veterinary surgeons supervising reproductive efficiency and piglet performance in breeding herds. These data include: the number of litters produced per sow per year; the distribution of weaning to service intervals; the number of sows returning to service by 30, 60, 90 and 120 days; the percentage of sows farrowing to first service; the percentage of sows found to be not pregnant; and the percentage of sows aborting. Boar performance data, piglet mortality percentages, piglet growth rates, feed efficiency factors and the percentage of sows culled from the herd are also analysed. A computer program was developed to produce these and other data from simple breeding records.

Animals↗
PubMed1992

Effects of nutrient deficiencies and excesses on reproductive efficiency of livestock.

Successful reproduction is dependent on a host of macro- and micronutrients and ceases well before an animal expires from deficiency of a particular nutrient. This review focuses on the functional roles phosphorus, vitamin A and beta-carotene, protein, and energy play in reproductive processes. Although it is not known whether deficiencies of these nutrients limit reproduction through common or discrete mechanisms, appropriate quantities of these nutrients are required for optimal reproduction. Mechanisms through which nutritional status is perceived by the hypothalamic-pituitary-gonadal axis remain unclear but seem to impinge on hypothalamic regions that selectively regulate production and release of pituitary trophic hormones. Body condition, or degree of fatness, seems to be the most reliable indicator of well-being of an animal, and, when coupled with changes in BW, provides a useful method to assess reproductive potential.

Animal Nutritional Physiological Phenomena↗
PubMed1977

The reproductive efficiency of the Xhosa.

Four sociogeographical groups of Xhosa were studied to show differences in their reproductive efficiencies. The rural groups showed increased perinatal, infant and over-all death rates compared with the urban groups. The highest death rate in all groups was during the infant period. The infant mortality was about 25% among the rural groups and 10% among the urban groups.

Black or African American↗
PubMedDate not supplied

[Influence of temperature and humidity on the reproductive efficiency of Ixodes ricinus (Linnaeus, 1758) and Hyalomma marginatum Koch, 1844 (Ixodoidea, Ixodidae)].

Laboratory studies have been carried out on two species of ticks, I. ricinus and H. marginatum, showing different seasonal activity and different geographical distribution in nature. The purpose of the present study has been to investigate the effect of different combinations of temperature and humidity on the oviposition of I. ricinus and H. marginatum. An index of reproduction efficiency (no. eggs/wt female), established to relate the capacity of the females to produce eggs to their body weight, has been calculated; for I. ricinus 5 temperatures (18-20-25-27 and 30 degrees C) have been studied (Fig. 1), for H. marginatum 3 (25-30 and 32 degrees C) (Fig. 2) and for both species 2 R.H. (75-95%). An optimal range of temperature, within which the value of such an index doesn't change, has been demonstrated for both species by statistical testing (Table 1). A critical weight value as the minimum engorged female weight required for egg deposition has been identified with the weight of first female which has laid eggs. This weight, different in each species, is influenced by temperature and humidity.

Animals↗
PubMed1992

Feeding to optimize canine reproductive efficiency.

The relationship between nutrition and reproduction is a topic of importance to veterinarians and breeders. Nutrient deficiencies, excesses, and imbalances all are capable of altering reproductive performance. Healthy adult dogs should be fed a diet high in digestibility, low in residue, and high in nutrient bioavailability. Rarely is nutritional intervention necessary during the first half of gestation. During the last half of gestation, switching to a growth/lactation diet and increasing intake by 1.2 to 1.4 x maintenance is indicated. Depending on breed and pup numbers, at peak lactation, feed intake may need to be increased by 2 to 4 x maintenance. The feeding goals of lactation are to minimize loss of bitch body condition score and optimize milk production and pup growth. After weaning, the female who is in poor body condition should remain on a diet rich in protein, fat, and trace nutrients until she is physically/nutritionally repleted.

Animal Feed↗
PubMed1976

Reproductive efficiency as a social indicator.

An index of reproductive effiency (RE) is proposed as a social indicator that will meet the need to consider various forms of pregnancy wastage, to compare their relative costs, and to guide reproductive health policy accordingly. This article discusses conceptual and measurement aspects of RE. Conversion of wanted to unwanted pregnancies and the reverse, interpretation of abortion in relation to other pregnancy outcomes, defining the end point for the reproductive process and criteria for the events to be included as significant outcomes are conceptual issues. Measurement problems include: whether aggregation is justified, prospective and retrospective tracking of outcomes, record limitations, duplication of adversities in a single pregnancy, and selection of optimal rate for comparison. A measurement of RE for the entire United States based on the National Natality Survey of 1964-1966 is presented, showing 74.5 percent of pregnancies resulting in healthy liveborn infants. For those years, data on abortions could not be included. Within the group of reported pregnancy losses, the importance of congenital abnormalities and low-birth-weight babies is enhanced by application of economic weights based on associated medical care costs. Changing opportunities for birth timing, prenatal and infant care, and control of family size are social means of reducing adverse outcomes associated with teenage pregnancy and high-parity births, often found together with poverty. Successive increments in RE may be progressively more expensive to achieve, and cost effectiveness comparison will be necessary.

Abortion, Legal↗
PubMed1976

Effects of a low-protein diet during pregnancy of the rhesus monkey I. Reproductive efficiency.

Pregnant rhesus monkeys were fed a control diet of modified cow's milk or an experimental diet containing only 25% as much as protein but made isocaloric with supplemental lactose. The ad libitum consumption of the control and experimental diets provided about 2 and 0.5 g of protein/kg of body weight per day, respectively. Total volume and energy consumption of control and experimental animals were generally comparable per kilogram of body weight, with groups showing a reduction in intake of about 20% during the latter part of pregnancy. Control females gained an average of 1.3 kg during pregnancy compared to 0.02 kg by the monkeys fed the low-protein diet. One of 15 infants born to control animals died shortly after birth; eight of 16 pregnancies in animals on the low-protein diet resulted in maternal and fetal death, stillbirth, or death in the newborn period. The birth weight of full term infants from mothers fed the low-protein diet was depressed by about 15%, and fetal linear growth was affected very little, but fetal and perinatal survival were low. We conclude that growth measurements of the newborn infants were relatively insensitive indices of the severity of the maternal nutritional deficiency and of the prognosis for the infant.

Abortion, Spontaneous↗
PubMed1975

Toxicity of certain polychlorinated and polybrominated biphenyls on reproductive efficiency of caged chickens.

The biphenyls tested with caged White Leghorn pullets were polychlorinated biphenyl (PCBs) Aroclors 1232, 1242, 1248, 1254 and 1016 and polybrominated biphenyl (PBB) PBP-6 at the 5, 10 and 20 p.p.m. levels. These pollutants exerted no adverse effects on egg production, egg weight, egg shell thickness, feed consumption, adult body weight changes, livability and fertility after 8 weeks of biphenyl feeding, irrespective of biphenyl level or compound. Hatchability of fertile eggs as a result of biphenyl feeding was significantly affected by 10 or 20 p.p.m. and by three PCB compounds (Aroclors 1232, 1242, 1248). The hatchability (%) of eggs laid by pullets fed 10 and 20 p.p.m. declined to 78 and 45, respectively, for Aroclor 1232, 48 and 5 for Aroclor 1242 and 40 and 5 for Aroclor 1248 after 6 weeks of biphenyl feeding, as compared with 90 for the control group. The most common embryonic abnormality was edema in the neck and rump areas. Biphenyl supplementation in the maternal diet also caused a shift in the peak pattern of embryonic death. Progeny growth as a result of biphenyl in the maternal diet was significantly depressed by 10 or 20 p.p.m. and by Aroclors 1242 and 1248. The level of the three PCBs found to be toxic to chickens appears to lie somewhere between 5 and 10 p.p.m.

Animals↗