Dam Weight Research Articles

A STUDY OF SOME ECONOMIC TRAITS OF MAMESH SHEEP IN ERBIL

This work was carried out on 77 Iranian Mamesh sheep raised at private flock in Erbil plain to study the effect of some non - genetic factors on Birth Weight (BW), Weaning Weight (WW), Daily Gain (DG) on Milk Production (MP). The overall means of BW, WW, DG and MP were 4.99 kg ,30.44 kg ,0.283 kg and 894.85g, respectively .Type of birth ,sex of lamb ,weight and age of dam affected BW,WWand DG significantly (P

Inactivation of FIP200 Leads to Inflammatory Skin Disorder, but Not Tumorigenesis, in Conditional Knock-out Mouse Models

FIP200 (focal adhesion kinase family interacting protein of 200 kDa) has been shown to interact with other proteins to regulate several intracellular signaling pathways. To study a potential role of FIP200 in tumorigenesis and possibly other disease processes in vivo, we created and analyzed murine mammary tumor virus-Cre-mediated FIP200 conditional knock-out (CKO) mice. We found that deletion of FIP200 in mammary epithelial cells did not result in spontaneous development of breast cancer. Moreover, deletion of FIP200 did not further accelerate or inhibit lymphomagenesis induced by inactivation of p53 in mice. Interestingly, however, FIP200 and p53 double conditional knock-out (dCKO) mice exhibited significant hyperplasia of epidermis (acanthosis), thickening of the cornified layer (hyperkeratosis), and increased vascularity in the dermis. FIP200 CKO mice also showed similar, although less severe, skin defects as dCKO mice. Analyses of primary keratinocytes isolated from dCKO mice did not detect increased proliferation of these cells in vitro, suggesting that epidermis hyperproliferation is not epidermal cell-autonomous but may be a consequence of increased inflammation triggered by immune cells in vivo. Consistent with this possibility, we found infiltration of leukocytes including T cells, macrophages, and granulocytes into the dermis and epidermis, associated with activation of NF-kappaB and increased expression of several proinflammatory cytokines and chemokines in skin of the dCKO mice. We further found that cultured FIP200 KO keratinocytes showed reduced NF-kappaB phosphorylation in response to tumor necrosis factor alpha stimulation, suggesting a paracrine regulation of aberrant NF-kappaB activation in the skin microenviroment of dCKO and FIP200 CKO mice. Together, these results demonstrate that ablation of FIP200, although not promoting tumorigenesis, can lead to skin inflammatory disorders, suggesting a novel function of FIP200 in the maintenance of normal skin homeostasis in vivo.

Maternal Isobutyl-Paraben Exposure decreases the Plasma Corticosterone Level in Dams and Sensitivity to Estrogen in Female Offspring Rats

Isobutyl-paraben (IBP), a widely used preservative in a variety of foods, shows high comparative binding affinity to estrogen receptors. Here, we examined the effects of maternal exposure of rats to IBP on plasma hormone concentrations and organ weights in dams, ratio of male pups, anogenital distance, organ weights and plasma hormone concentrations in offspring, puberty, estrous cycle and response of organ weight and plasma hormone concentrations to estrogen in adult female offspring, and reproductive and adrenal function in adult male offspring, all of which are under developmental estrogen regulation, to clarify the estrogenic effects of IBP during gestation and lactation on the endocrine systems of dams and offspring. While maternal exposure of IBP decreased the plasma corticosterone concentration and increased the uterus weight in dams and increased uterine sensitivity to estrogen in adult female offspring, the other indices examined were largely unaffected by the present treatment. Even though these results indicate little sign of endocrine disrupting effects for IBP, the existence of activity may be a matter of concern due to the possible impact on the health of future generations.

Effects of porcine circovirus type 2 and mycoplasma hyopneumoniae vaccination strategy, birth weight, and gender on postweaning performance of growing-finishing pigs reared in a commercial environment (2009)

A total of 1,995 pigs were used to evaluate the effects of two porcine circovirus type 2 (PCV2) and Mycoplasma hyopneumoniae (Mhyo) vaccination strategies and birth weight on pig performance and carcass characteristics. The first vaccination strategy (BI) was a single full dose of CircoFLEX-MycoFLEX (Boehringer Ingelheim, St. Joseph, MO) at weaning. The second strategy (Intervet) was a full dose of Circumvent and MYCOSILENCER (Intervet/Schering-Plough Animal Health, Millsboro, DE) at weaning and again 22 d later. At a commercial sow farm, all pigs born alive for 22 consecutive days were identified individually at birth with a numbered ear tag. The dam, gender, and birth weight were recorded and used to randomly allot pigs at weaning (d 0) to the PCV2/Mhyo vaccination treatments. The pigs were weaned into 4 consecutive nursery rooms of approximately 500 pigs each on 6 occasions during a 19-d period. Pigs from each vaccination treatment were comingled in pens within rooms throughout the study. Pigs were moved to a finishing barn on d 74. Pigs were individually weighed on d 0, 22, 44, 74, and 156 to measure growth rate. Carcass data were obtained from a subsample of 420 pigs harvested on a single day (d 167). For data analysis, individual birth weight was used to assign pigs to 7 birth weight categories, each containing a similar number of observations. Therefore, data were analyzed as a 2 × 2 × 7 factorial arrangement in a completely randomized design with main effects of vaccine strategy, gender, and weight category. As birth weight category increased, ADG increased (P < 0.01) during each weight period and overall. Percentage of culls and light weight pigs at market also were reduced (P < 0.01) as weight category increased. Overall, ADG, final BW, HCW, and backfat depth of barrows were increased (P < 0.0001) compared with gilts, whereas the percentage of culls and pigs < 215 lb and fat-free lean were reduced (P < 0.0001) compared with gilts.

Deletion of corticotropin-releasing factor binding protein selectively impairs maternal, but not intermale aggression

Corticotropin-releasing factor (CRF) binding protein (CRF-BP) is a secreted protein that acts to bind and limit the activity of the neuropeptides, CRF and urocortin (Ucn) 1. We previously selected for high maternal defense (protection of offspring) in mice and found CRF-BP to be elevated in the CNS of selected mice. We also previously determined that both CRF and Ucn 1 are potent inhibitors of offspring protection when administered centrally. Thus, elevated CRF-BP could promote defense by limiting endogenous actions of CRF or Ucn 1. To test this hypothesis, we crossed the deletion for CRF-BP into the mice selected for high maternal defense and evaluated offspring protection and other maternal behaviors. CRF-BP knockout (KO) mice exhibited significant deficits in maternal aggression relative to wild-type (WT) mice in three different measures. Other maternal features were almost identical between groups, including dam and pup weight, litter size, nursing time, and pup retrieval. Both groups performed similarly in a forced swim stress test and aggression in both groups was reduced following the swim test. Virgin KO female mice exhibited higher levels of anxiety-like behavior in terms of decreased time in the light portion of the light/dark box test. For males, no differences in light/dark box or swim test were found. However, increased anxiety-like behavior in male KO mice was identified in terms of contact and approach to a novel object both with and without previous exposure to the swim test. No differences in isolation induced resident intruder male aggression were found between groups. Together, these results indicate that loss of CRF-BP selectively impairs maternal, but not intermale aggression and that loss of the gene induces anxiety-like behavior in males and females, but there are sex differences in terms of how that anxiety is revealed.

Eficiência reprodutiva e influência de fatores de meio e de herança sobre a variação no peso ao nascer de bubalinos no estado de Rondônia

Avaliaram-se as características reprodutivas e o peso ao nascer em bubalinos mestiços e determinaram-se os possíveis fatores de sua variação. Utilizaram-se 115 informações de idade ao primeiro parto e 420 intervalos de parto referentes a 127 fêmeas 1/2, 3/4, 7/8, 15/16 Murrah × Mediterrâneo e puras por cruza (PC). Também foram utilizados 557 pesos ao nascer de progênies resultantes do cruzamento entre essas fêmeas e cinco touros da raça Murrah. Os nascimentos ocorreram no período de 1979 a 2001. A idade ao primeiro parto (1291 ± 235 dias) foi influenciada pelo grupo de contemporâneos da búfala. O intervalo de partos (451 ± 139 dias) foi afetado pelos efeitos fixos grupo de contemporâneos da búfala; peso da búfala no pós-parto anterior; idade da búfala ao parto anterior, linear e quadrática; bem como, pelo efeito aleatório de búfala. O grupo genético não determinou variações sobre as características idade ao primeiro parto e intervalo de partos. O peso ao nascer (34,25 ± 5,02 kg) foi influenciado pelo sexo da cria, pelo grupo de contemporâneos do bezerro e pelo peso da búfala após o parto, além do efeito aleatório de mãe. O grupo genético da búfala, a idade da búfala ao parto e o pai da cria não influenciaram o peso ao nascer. A herdabilidade estimada do peso ao nascimento foi de 0,60 ± 0,12. Os fatores que apresentaram diferenças significativas devem ser considerados na avaliação das características reprodutivas e do peso ao nascer.

Effect of supplementation of Sesbania sesban on reproductive performance of sheep

Two successive experiments were conducted to investigate the long-term effects of supplementation of Sesbania sesban on reproductive performance of Ethiopian Menz sheep. Forty ewes and 40 rams ranging in weight and age between 16–20 kg and 14–15 months respectively were fed a teff straw basal diet and supplemented with two levels of Sesbania (0, and 95% of supplementary protein provided by Sesbania and the rest being provided by concentrates) for 7 months. In experiment 1 (mating period), 4 paired female–male groups (diet of the male with or without Sesbania, and diet of the female with or without Sesbania) consisting of 20 animals each were formed and assigned for mating. Ewes that were mated and did not return to heat in subsequent cycles during the 70 days mating period continued in experiment 2 receiving similar supplementary diets (concentrate alone or Sesbania) for the study of pregnancy and lambing. During the mating period, males and animals supplemented with Sesbania were superior ( P < 0.05) in daily feed nutrients intake, whereas daily body weight gain (ADG) was significantly different ( P < 0.05) between treatments but not between sex groups. During pregnancy a significant difference ( P < 0.05) was observed only in nitrogen intake, and ADG of ewes did not differ ( P > 0.05) between treatments. Supplementation with Sesbania promoted an increase in testicular size by 13%. Except semen concentration, the other seminal characteristics were not significant ( P < 0.05) between treatments. The average oestrus cycle length was 19 ± 4.6 days. Mean progesterone profile for cycling ewes on the day of oestrus was 0.4 ± 0.04 and ranged between undetectable levels to 0.75 ng/ml followed by a rise starting on day 4 (1.7 ± 0.16 ng/ml) through day 7 (2.5 ± 0.29 ng/ml) and day 10 (3.6 ± 0.47 ng/ml) to a peak of 3.9 ± 0.45 ng/ml (plateau phase) on day 14. Supplementation with Sesbania improved the proportion of ewes conceived by 17% over supplementation with concentrates. The average birth weight of lambs, and post partum dam weight of ewes was 1.97 kg and 18.6 kg respectively and differed significantly ( P < 0.05) between treatments. We concluded that inclusion of Sesbania up to 30% in the diet of sheep as supplement before and during the period of mating and pregnancy improved testicular growth and semen quality in rams or reproductive performance of ewes without showing negative effects.

Milk Production in Awassi Sheep and their Crosses with Assaf under Accelerated Lambing System

At the Sheep Breeding Station, IPA Agricultural Research Center, milk production was investigated in&#x0D; 92 Iraq Awassi (AW) and 95 Assaf x Awassi (AA) ewes under accelerated lambing system , together with effects of age&#x0D; and body weight of ewe , lambing season and sex by litter size of lamb using General Linear Model (GLM)&#x0D; procedure . The overall means of milk yield and lactation period were 85.64 kg and 132.36 days, respectively.&#x0D; AA ewes surpassed significantly AW ewes in milk yield (99.15 vs. 74.99 kg) and lactation period (139.0 vs.126.8&#x0D; days).Age, weight of dam at lambing and sex by type of birth of lamb had significant effects on milk yield. Milk&#x0D; produced by ewes lambed at first season was significantly higher than ewes lambed during second and third season.

Subsidence and uplift of Sidoarjo (East Java) due to the eruption of the Lusi mud volcano (2006–present)

Global positioning system (GPS) and satellite-based InSAR (Interferometric Synthetic Aperture Radar) measurements of the subsidence and uplift of a populated area of Sidoarjo, East Java are due to the eruption of the Lusi mud volcano (2006–present). These data are the first direct quantitative measurements of deformation due to the growth of a mud volcano edifice. The GPS data were recorded over periods of a few hours to several months and show that between June 2006 and September 2007, the earth’s surface has been subsiding at rates of 0.1–4 cm/day. Maximum rates of subsidence occurred in an area 300–400 m to the northwest of the main mud volcano vent. Horizontal displacements were 0.03–0.9 cm/day and were also towards this area. In general uplifts of up to 0.09 cm/day were recorded in areas outside of the edifice. Changes in elevation measured using satellite imagery (InSAR technique) provide regional datasets of subsidence and uplift. They confirm that during the first year a roughly circular area was undergoing sag-like subsidence centered to the northwest of the main vent and that uplift was occurring 3–4 months after the initiation of the eruption due to the movement Watukosek fault system. Subsidence occurred due to the weight of mud and man-made dams and the collapse of the overburden due to removal of mud from the subsurface. Assuming constant rates of subsidence of 4 cm/day, then in the centre of the edifice there would be up to 44 m of subsidence in 3 years, and up to 16 m in 10 years. The mud volcano is now in a self-organizing state with new fluid conduits forming as a result of the collapse.

CRESCIMENTO DE CABRAS SAANEN, ALPINA E TOGGENBURG NO DISTRITO FEDERAL: FATORES GENÉTICOS E AMBIENTAIS

Data from 1215 kids, with 402 Saanen, 396 Alpine, 200 Toggenburg and 217 ½ Alpine goats, was collected on growth of goats in the Federal District, Brazil from 1995 to 2001. For variance analyses were considered as fixed effect farm, breed, sex, kidding type, month and year of kidding and weight of dam as a covariable. Traits as birth weight and growth from birth to weaning and weaning to first insemination were studied. There was a significant effect of breed, sex and type of kidding on birth weight while weaning weight was only influenced by breed. Month and year of kidding were significant in influencing growth rate after birth. Number of days to insemination weight was influenced by both breed and month of kidding while the insemination weight itself was not influenced by any of the factors studied. Insemination weight was lowly correlated with the other traits in the study, as was to be expected. Days to insemination weight was most highly and negatively correlated with growth rate after weaning and weaning weight showing that faster growing animals that were larger at weaning reached insemination weight more quickly. The correlation between weaning weight and growth rate after weaning was low indicating that animals heavier at weaning did not necessarily grow faster after weaning. Key words: Correlation, growth curve, heritability, housed, weight .

Effect of birth weight, gender and litter characteristics on summer mortality in lambs of Norwegian breeds

This study describes how birth weight, gender, litter size, and age of dam affect lamb mortality during the summer period, using data on lambs of the breeds Spælsau (N ≈ 110 000) and Norwegian White Sheep (N ≈ 450 000) during 1994 to 2005. A general mixed linear model was used for the analysis. Birth weight affected summer mortality non-proportionally: an increase in weight from very small towards the breed mean strongly deflated mortality risk; weigh increase above breed means had little effect. Male lambs had a higher mortality than females, and lambs born by 12-months-old dams were in greater risk than those having older dams. Increasing litter size resulted in increased mortality. The results are discussed and recommendations for future research, with focus on breeding and genotype by environment interaction effects are made.

Hepatic and Thymic Alterations in Newborn Offspring of Malnourished Rat Dams

Protein-energy malnutrition encompasses a group of conditions resulting from a lack of both protein and calories. It affects immune function and the gastrointestinal tract. Animal model studies of the effect of malnutrition during pregnancy and lactation have shown changes in the body weight of dams, with consequences for the pups. Sixty healthy adult Wistar rats were mated for breeding. Pregnant dams (n = 19) were separated and randomly divided into 2 groups: normally nourished (NG; n = 10) and malnourished (MG; n = 9). The authors measured the average amount of feed eaten by the dams in the NG group in 24 hours and offered half this amount to the MG dams until delivery, after which both groups had an adequate amount of feed. Offspring were killed after birth and after lactation. Morphometric liver parameters were measured, and the tissue microarray method was performed manually to carry out histopathological and immunohistochemical analysis of thymuses from the offspring. Body weight, body length, and intestine length measured after birth were statistically lower (P < .05) in the MG group offspring than in the NG group offspring but recovered after lactation. Histological comparison of pups' livers revealed minimal differences. However, morphometric evaluation showed significant differences. Slides exposed to antivimentin and anti-CD45 RO stained positively in both groups, but the samples from the NG group were more heavily stained. Malnutrition in dams causes alterations in the liver, thymus, and other internal organs of newborn offspring. Significant changes in thymuses were found using human monoclonal antibodies that cross-react with rat proteins, a novel finding in the literature.

Gestation stage‐dependent changes in monoclonal antibody pharmacokinetics and function during rat pregnancy

We studied monoclonal IgG1 antibody (mAb) pharmacokinetics (PCKN) and in vivo function in pregnant rats from gestation day (GD) 8 to GD21 (1–2 day antepartum). On GD8, pregnant rats (n=4) received an iv‐bolus dose of 15 mg/kg of anti‐phencyclidine mAb6B5 or anti‐methamphetamine mAb6H4 along with a [3H]‐mAb tracer. PCKN analysis of serum mAb concentration‐time data showed significant (p&lt;0.001) gestation stage‐dependent changes in terminal elimination half‐life (t1/2λz) for both mAb's. From GD9 to ~GD15‐GD18, the t1/2λz of mAb6B5 and mAb6H4 were 3.6 ± 0.4 and 3.1 ± 0.3 days, respectively. However, between ~GD15‐GD18, the t1/2λz of these mAb's abruptly decreased to 1.0 ± 0.1 and 1.1 ± 0.2 days, respectively. When 15 mg/kg mAb6B5 was dosed on GD15, we found a similarly decreased late‐gestation t1/2λz of 1.4 ± 0.2 days. Importantly, IgG1 PCKN was dose‐independent, since a 90 mg/kg mAb6B5 dose on GD8 demonstrated the same PCKN profile from GD8‐GD21 as the 15 mg/kg mAb6B5 dose. In vivo mAb6B5 serum phencyclidine (PCP) binding in the presence of infused PCP also showed decreased mAb function starting at ~GD15. We observed that the dramatic decrease in mAb t1/2λz and function always coincided with the start of an accelerated dam weight gain. These findings represent an important step in understanding mAb PCKN and function during pregnancy. (Funded by NIDA DA07610, Kirschstien NRSA DA24522, and a GlaxoSmithKline fellowship).

Effect of Prenatal and Postnatal Exposure to an Aqueous Extract of Hibiscus sabdariffa (HS) on Postnatal Growth in Sprague-Dawley Rats

The present study was designed to investigate whether pups exposed to aqueous extract of HS during the foetal period and during early postnatal period would have a comparable growth with control pups in accordance with the “predictive adaptive response” hypothesis. Three groups of pregnant Sprague-Dawley (SD) rats were used for this study. Group C had tap water while groups A and B had 0.6g/100ml and 1.8g/100ml HS extract respectively to drink throughout pregnancy and through 20 days postpartum. All groups had normal rat chow ad libitum. Dam weights were recorded daily throughout pregnancy and through 20 days postpartum while pup weights were recorded at birth, 10 days, 14 days and 20 days postpartum. Results of the present study show no statistically significant difference (p>0.05) in the growth of pups at 10, 14 and 20 days postpartum in all groups except for group B pups whose growth was lower (p<0.05) at 20 days postpartum. We conclude that prenatal and early postnatal exposure to an aqueous extract of Hibiscus Sabdariffa does not appear to affect early postnatal growth in Sprague-Dawley rats.

Fish-Oil High-Fat Diet Intake of Dams after Day 5 of Pregnancy and during Lactation Guards against Excessive Fat Consumption of Their Weaning Pups

To investigate the influence of parental fat intake on preferential fat intake by pups after weaning, two groups of dams in study 1 were fed either a low-fat diet (LFD) or a lard high-fat diet (HFD) and those in study 2 were fed either a LFD or a fish-oil HFD after day 5 of pregnancy and during lactation. In study 1, when pups were placed on a self-selection regimen of the LFD and the lard HFD within the first week after weaning, the ratio of the lard HFD intake [lard HFD intake (g)/total intake (g)] by pups of both groups was about 70%. Although pups nursed by dams fed the lard HFD continued to eat the same ratio of the lard HFD, the ratio for pups nursed by dams fed the LFD gradually decreased to 20% in week 3 after weaning. In study 2, when pups were placed on a self-selection regimen of the LFD and the fish-oil HFD after weaning, the ratio of the fish-oil HFD intake in both groups of pups nursed by dams fed the LFD and the fish-oil HFD was about 20% for 3 wk after weaning. In studies 1 and 2, although no significant difference in dietary intake or body weight of dams and pups was observed among all groups through the experimental period, perirenal fat tissue weight of dams fed the lard HFD was higher than that of dams fed the LFD. These findings indicate that (1) fat preference of weaning pups nursed by dams fed the lard HFD is higher than that of weaning pups nursed by dams fed the LFD, and (2) intake of dam's fish-oil HFD diet guards against pups' intake of excessive fat.

Dam deformation measurements with GPS

The results of deformation measurements are related to safety of engineering structures and human life. To avoid a wrong interpretation of displacements, an appropriate deformation monitoring network must be established and the data obtained from deformation monitoring network must be carefully evaluated. Deformation measurements and analysis require the use of very accurate surveying equipment and analysis methods. The Global Positioning System (GPS) meets all the requirements stated above and therefore GPS receivers were used for this research. The purpose of this work was to monitor and analyze the deformation at the crest of the Altınkaya dam which was caused by the water load at different water levels combined with the dam’s weight. The secondary goal was to determine whether GPS measurements could meet the accuracy requirements for dam deformation measurements. As working area the Altınkaya dam is selected as a rockfill. In order to monitor and examine the deformation, a monitoring network consisting of 6 reference points and 11 object points was established. Measurements were made 4 times over 2 years using dual frequency GPS receivers with static methods. The measurements were performed and point coordinates have been determined. Then differences were calculated between periods and analyzed by iterative weighted transformation and Least Absolute Sum methods to determine the points stability. Article in English Užtvankų deformacijų matavimai taikant GPS Santrauka. Su deformacijų matavimų rezultatais tiesiogiai susijusi grėsmė inžineriniams statiniams ir žmonių gyvybei. Siekiant išvengti klaidingų poslinkių interpretacijų turi būti įrengti tinkami deformacijų monitoringo tinklai, o gaunami duomenys rūpestingai vertinami. Deformacijų matavimai ir analizė turi būti atliekami labai tiksliais geodeziniais prietaisais ir tyrimo metodais. Globalinė padėties nustatymo sistema (GPS) tokius reikalavimus atitinka, todėl ir atliekant šį tyrimą taikyti GPS imtuvai. Darbo tikslas buvo stebėti ir analizuoti Altinkaya užtvankos sprūdį, kurį, be pačios užtvankos svorio, lėmė vandens pakilimas įvairiais lygiais. Kitas tikslas buvo nustatyti, ar GPS matavimai atitinka užtvankų deformacijų matavimo tikslumo reikalavimus. Darbo vieta parinkta Altinkaya – užtvanka iš akmenų. Deformacijų stebėsenai ir tyrimui sudarytas 6 atraminių punktų ir 11 stebimų taškų tinklas. Matavimai atlikti statiniu metodu 4 kartus per dvejus metus taikant dvidažnius GPS imtuvus. Duomenys apdoroti, ir rastos taškų koordinatės. Nustatyti matavimų periodų koordinačių skirtumai. Jie analizuoti taikant iteracinį svorinį transformavimą. Punktų stabilumas nustatytas mažiausiųjų absoliučiųjų sumų metodu.

Effects of prenatal exposure to the CB-1 receptor agonist WIN 55212-2 or CO on the GABAergic neuronal systems of rat cerebellar cortex

The aim of this study was to assess the effects of prenatal exposures to cannabinoids or carbon monoxide (CO) in an animal experimental model reproducing the environmental conditions in which a fetus develops whose mother, during pregnancy, ingests by smoking low doses of cannabinoids or CO. Particular attention was devoted to analyses of the long-term effects of the exposures at the level of the cerebellar cortex, where already during prenatal development the GABAergic neuronal systems may be modulated by both cannabinoids and CO. Three groups of rats were subjected to the following experimental conditions: exposure to cannabinoids by maternal treatment during pregnancy with the cannabinoid CB-1 receptor agonist WIN 55212-2 (WIN) (0.5 mg/kg/day, s.c.); exposure to CO by maternal exposure during pregnancy to CO (75 parts per million, by inhalation); and exposure to WIN+CO at the above doses and means of administration; a fourth group was used as control. The body weight of dams, length of pregnancy, litter size at birth, body weight and postnatal mortality of pups were monitored in order to evaluate possible effects of the exposures on reproduction and on prenatal and postnatal development. In the different groups, the long-term effects of the exposures were studied in adult rats (120–150 days) by light microscopy analyses of the structure of the cerebellar cortex and of the distribution in the cortex of markers of GABAergic neurons, such as GAD and GABA itself. Results. Exposures to WIN or CO did not affect reproduction or prenatal/postnatal development. Moreover, the exposed rats showed no structural alterations of the cerebellar cortex and displayed qualitative distribution patterns of GAD and GABA immunoreactivities similar to those of the controls. However, quantitative analyses indicated significant changes of both of these immunoreactivities: in comparison with the controls, they were significantly increased in WIN-exposed rats and reduced in CO-exposed rats, but not significantly different in WIN+CO-exposed rats. The changes were detected in the molecular and Purkinje neuron layers, but not in the granular layer. Prenatal exposures of rats to WIN or CO, at doses that do not affect reproduction, general processes of development and histomorphogenesis of the cerebellar cortex, cause significant changes of GAD and GABA immunoreactivities in some GABAergic neuronal systems of the adult rat cerebellar cortex, indicating selective up-regulation of GABA-mediated neurotransmission as a long-term consequence of chronic prenatal exposures to cannabinoids or CO. Because the changes consist of overexpression or, vice versa, underexpression of these immunoreactivities, functional alterations of opposite types in the GABAergic systems of the cerebellum following exposure to WIN or CO can be postulated, in agreement with the results of behavioral and clinical studies. No changes in immunoreactivities were detected after prenatal exposure to WIN and CO in association.

CONTRASTING EFFECTS OF AD LIBITUM AND RESTRICTED FEEDING OF A DIET HIGH IN SATURATED FAT ON THE SEX RATIO OF PUPS BORN TO MATURE NIH SWISS MICE

Pronounced skewing of the sex ratio towards males occurs among pups born to mature NIH Swiss dams fed continuously on a diet very high in saturated fats (VHF diet). Conversely, mice fed a nutritionally complete but low fat/high carbohydrate diet produce significantly more daughters than sons. Sex ratio deviation from the expected 0.5 value relates to the diets fed rather than dam weight and is observed with no change in litter size. Here, we tested the hypothesis that the high lard content of the VHF diet rather than the calories consumed by the dams is responsible for the increase in sex ratio among the pups. To accomplish this, mice eight weeks of age were placed permanently on the VHF diet (lard supplying 54 % of the calories; caloric density 5.2 kcal/g) either ad libitum (VHF group) or in a restricted manner (∼7 h access to food during their night: VHF-R group). Under the latter conditions, the VHF-R mice gained weight at a similar rate to controls fed Purina 5015 (calories from fat 26 %; caloric density 4.4 kcal/g). Mice (n=12/group) were first bred at 15 weeks of age and subsequently at 25.5, and 35 weeks. Pup sex was assessed at day 2 and confirmed at weaning by two independent observers. The VHF, VHFR and 5015 groups produced 27, 30 and 33 litters, respectively and 244, 242, and 274 total pups, with sex ratios (fraction males) of 0.54, 0.59, 0.79 (VHF); 0.45, 0.48, 0.35 (VHF-R), and 0.5, 0.5, 0.44 (Control, 5015 diet) respectively. The sex ratios in the VHF and 5015 and VHF and VHF-R groups differed significantly (each p< 0.0001). There was also a tendency of sex ratio to increase with parity in the VHF group, as had been noted by Rosenfeld et al. (2003). No difference was detected in sex ratio between the VHF-R and 5015 groups, although pup mortality in the immediate postnatal period was significantly higher in the VHF and particularly the VHF-R group, where the mothers failed to gain body mass at a comparable rate to the ad libitum fed controls as they began to lactate. These experiments confirm that the high fat diet strongly biases pup sex ratio towards males and suggests that the skewing of the sex ratio in favor of sons in VHF dams is a consequence of calories consumed rather than the high saturated fat content of the diet. However, an alternative explanation for the low sex ratio of pups from the VHF-R group is that stress induced by the restricted access to food may have favored a higher fraction of female pups than when the VHF diet was fed ad libitum. Supported by NIH Grant HD 044042 (poster)

A two-generational reproductive toxicity study of zinc in rats

A two-generation reproductive toxicity study of zinc chloride (ZnCl2) was conducted in rats. Fo male and female rats were administered 0.00 (control), 7.50 (low), 15.00 (mid) and 30.00 (high) mg/kg/day of ZnCl2. Selected F1 male and female rats were exposed to the same doses received by their parents (Fo). Exposure of F0 parental rats to ZnCl2 showed significant reduction in fertility, viability (days 0 and 4), and the body weight of F1 pups from the high-dose group but caused no effects on litter size, weaning index, and sex ratio. Similarly, the continued exposure of F1 parental rats to ZnCl2 also reduced fertility, liter size, viability (day 0), and the body weight of F2 pups within the high-dose group but caused no effects on weaning index and sex ratio. Exposure of ZnCl2 to F0 and F1 parental males resulted in a significant reduction in their body weights, and the F0 and F1 parental females did not show any significant difference in their body weights compared to their control groups. However, the postpartum dam weights of both F0 and F1 female rats were significantly reduced compared to their controls. Exposure of ZnCl2 to Fo and F1 generation parental rats did not produce any significant change of their clinical signs as well as their clinical pathology parameters, except the alkaline phosphotase (ALK) level, which showed an upward trend in both sexes of both generations. Exposure of ZnCl2 to F0 rats resulted in a reduction of brain, liver, kidney, spleen and seminal vesicles weights of males and in the spleen and uterus of females. Similarly, exposure of F1 rats to ZnCl2 also resulted in reduction of brain, liver, kidney, adrenal, spleen, prostate and seminal vesicles weights of males and in spleen and uterus of females. ZnCl2 exposure resulted in grossly observed gastro-intestianla (GI) tract, lymphoreticular/hematopoietic, and reproductive tract lesions in parental rats in both generations. Reduced body fat was also recorded in F1 parental rats.

A STUDY ON THE RELATIONSHIP BETWEEN BODY WEIGHT AND BODY DIMENSIONS OF LAMBS AT WEANING AND SELECTION OF HAMDANI EWES FOR MILK PRODUCTION

The relationships between body weight, body and fat tail dimensions of 119 hamdani lambs at weaning were studied. A total of 500 records of 115 hamdani ewes (test day milk yield) were analyzed. The overall mean of test-day milk yield was 0.414 kg. The effects of flock , age of dam , stage of lactation and body weight of dam on this trait were significant. Repeatability estimate for test-day milk yield was (0.52 ± 0.04) , and the estimated value of BLUP for ewe depending on milk yield ranged from (-155.56 to 214.58 gm ) for the first flock, and (-162.46 to 240.39 gm ) for the second flock. The overall mean of weaning weight (WW),body length (BL) hearth girth (HG), height at shoulder (HS) & at hip(HH) width at shoulder (WS) and at hip (WH) were 21.41 kg, 49.69 cm, 61.79 cm, 54.73 cm, 56.99 cm, 14.05 cm,16.99 cm, respectively .The overall mean of fat tail length (FL) , fat tail width (FW1) at the point of attachment with the body and at the middle point (FW2) were 13.81 cm , 20.30 cm and 23.83 cm, respectively. Positive correlation coefficients (p