Registration Dossier

Toxicological information

Toxicity to reproduction

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Administrative data

Endpoint:
screening for reproductive / developmental toxicity
Remarks:
based on generations indicated in Effect levels (migrated information)
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2005
Report Date:
2005

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 422 (Combined Repeated Dose Toxicity Study with the Reproduction / Developmental Toxicity Screening Test)
Qualifier:
according to
Guideline:
other: OECD 407,1995
Principles of method if other than guideline:
F1: continued exposure for 7 weeks after lactation period and assessments of neurologic, immunologic, and reproductive structures and functions.
GLP compliance:
yes
Limit test:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
Structure analogue

Test animals

Species:
rat
Strain:
Sprague-Dawley
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Charles River Breeding Laboratories, Raleigh, NC
- outbred albino CD® (Sprague-Dawley) rats (Crl:CD®[SD] IGS BR)
- females: nulliparous and nonpregnant
- Age at study initiation: ~ 63 days old on delivery, Exposure begin: (P) ~ 10 wks;
- Weight at study initiation: (P) Males: 276 - 300 g; Females: 201 - 225 g;
The weight variation of the study animals at initiation did not exceed ± 20% of the mean weight for each sex.
- Fasting period before study: No data
- Housing: individually upon arrival, during the acclimation period, and upon the initiation of the treatment period, 2 per cage (1 male:1 female
from the same dose group) during the mating period. Females were caged individually once they were successfully mated (or at the end of the mating period) and throughout gestation. Females were housed with their litters throughout the lactation period. Randomly selected F1 weanlings (10/sex/group), males, and females were singly housed during the postweaning exposure period.
- Diet (e.g. ad libitum): Pelleted Purina Certified Rodent Diet® (No. 5002, PMI Feeds, Inc., St. Louis, MO), ad libitum. The period of use did not exceed 6 months from the milling date.
- Water (e.g. ad libitum): Tap water (source: City of Durham, Department of Water Resources, Durham, NC), ad libitum
- Acclimation period: ~ 1 week


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3°C
- Humidity (%): 30-70%
- Photoperiod (hrs dark / hrs light): 12 h / 12 h


IN-LIFE DATES: From: To:

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
corn oil
Details on exposure:
PREPARATION OF DOSING SOLUTIONS:
- dosing formulations prepared in corn oil at concentrations of 2, 20, and 40 mg/ml approximately every 30 days were used within
the stability limits established, and were stored under refrigeration. All dosing formulations were analyzed for concentration verification.

VEHICLE
- Mazola® corn oil (CAS No. 599-64-4).
- Amount of vehicle (if gavage): at a dose volume of 5 ml/kg/day in Mazola® corn oil, based on the most recent body weight (through gd 14 for F0 females). Dosing volumes for gavage administration were adjusted during pregnancy, based on each dam's most recent body weight on gd 0,7, and 14, with no adjustment beyond gd 14 since the large maternal weight gain from gd 14 to 20 (~ 30%) was due to the growth of the uterine contents and not to any appreciable weight gain of the extra-uterine maternal animal. Therefore, the dosing volume set on gd 14 was used until pnd 0 to prevent overdosing the maternal animals during late gestation

OTHERS:
- Recovery males (5 each at 0 and 200 mg/kg/day) were dosed for 28 days and then held for 14 days without dosing, as a recovery period, until necropsy.
- Twenty-eight-day females and recovery females (5 each at 0 and 200 mg/kg/day) were also dosed for 28 days. The 28-day females were necropsied immediately after the last dose. The recovery females were held for 14 days without dosing until necropsy.
- The selected F1 offspring were administered TMP daily by gavage at the same dose as their parents, from pnd 22 (the day after weaning) until the day before scheduled necropsy (at least 7 weeks duration).
Details on mating procedure:
- After the 2-week prebreed exposure period, animals were randomly mated within treatment groups with no change in mating partners. Females were examined daily during the cohabitation period for the presence of sperm or copulation plug in the vaginal tract.
- M/F ratio per cage: 1 : 1
- Length of cohabitation: 2 weeks
- Proof of pregnancy: vaginal plug or sperm was referred to as day 0 of pregnancy
- Further matings after unsuccessful attempts: no, any female that did not show evidence of successful mating after 14 days of cohabitation was weighed weekly, and treatment continued until gd 26 or delivery occurred. If a female without a confirmed gd 0 date was, in fact, pregnant and delivered a litter, her lactational information was collected as described below.
- After successful mating each pregnant female was caged (how): individually
- The dams were allowed to rear their young to pnd 21. On pnd 21, each litter was weaned.
Analytical verification of doses or concentrations:
yes
Details on analytical verification of doses or concentrations:
Analyses of dosage formulations used were 90.8-108% of nominal concentrations.
Standards for acceptable accuracy of mixing were that the mean of the analyzed samples was within ± 10% of nominal concentration, and the % RSD (Relative Standard Deviation) for triplicate samples did not exceed 10%. All study formulations met these standards except for the 2.0 mg/ml dose formulated once (initially analyzed at 88.5±0.500 % of nominal).
When the archive sample was also analyzed, the mean concentration was within the range mandated (90.8 ± 2.60% of nominal) and was used to dose the animals.
Duration of treatment / exposure:
from the first day of prebreed to the day prior to necropsy, encompassing 2-week of prebreed exposure (males and females), 2 weeks of mating (for both sexes), 3 weeks of gestation and lactation each (for F0 females) for F0 parents,
and direct dosing of selected F1 offspring from weaning to scheduled sacrifice, at least 7 weeks postweaning.
Frequency of treatment:
once a day, 7 days per week
Details on study schedule:
- At weaning, at least 1 female and 1 male (whenever possible) from each F1 litter were randomly selected for a total of 10/sex/group to continue treatment for ~ 7 more weeks, with dosing for F1 selected pups begun on pnd 22 and continued until all pups were at least 70 days of age.

- All pups were available for selection except those not expected to survive because of physical abnormalities. Records were maintained on any pup excluded from the selection process.
- Any F1 pup that appeared moribund or that died during lactation was necropsied, when possible, to investigate the cause of death and to identify internal visceral developmental malformations, if any. Organs were not weighed for these animals.
Doses / concentrationsopen allclose all
Remarks:
Doses / Concentrations:
0, 100, 300, and 1000 mg/kg/day
Basis:
actual ingested
(dose range-finding study)
Remarks:
Doses / Concentrations:
0, 10, 100, and 200 mg/kg/day
Basis:
actual ingested
No. of animals per sex per dose:
There were 110 animals: 40 F0 males and 40 F0 females (10 animals/sex/group in 4 groups), 10 males and 10 females (5 additional males and females each in the control and high-dose groups, designated as recovery animals), and 10 females (5 females each in the control and high-dose groups, designated as the 28-day females, which were dosed for 28 days and then necropsied).
Control animals:
yes
Details on study design:
- Dose selection rationale: Doses were selected for the study based on the results of a 10-day dose range-finding (RF) study. In·this study, TMP was dosed by gavage to male and female rats for 10 consecutive days at 0, 100, 300, and 1000 mg/kg/day. Body weight loss over the 10-day period was observed for males at 1000 mg/kg/day and females at 300 and 1000 mg/kg/day. In addition, weight gain in males at 300 mg/kg/day was reduced by 43% compared to the controls. Therefore, 300 mg/kg/day was considered too toxic for the OECD 422 study design. Based on the findings in the RF study, the doses chosen for the reproduction study were 0, 10, 100, and 200 mg/kg/day.
- Rationale for animal assignment (if not random): Animals were assigned by sex to the different groups by means of randomization stratified by body weight, such that the body weights by sex of all groups were homogeneous at treatment initiation.

Examinations

Parental animals: Observations and examinations:
CAGE SIDE OBSERVATIONS: Yes,
• Observations for mortality: Time schedule: twice daily (a.m. and p.m.)
• General conditions of all animals: Time schedule: daily.
• Beginning on gd 20, each female was observed twice daily (a.m. and p.m.) for evidence of littering.

DETAILED CLINICAL OBSERVATIONS: Yes
• Clinical examinations were conducted and recorded. The record included the day of onset, and degree and duration of symptoms.
• Time schedule: at least once daily for F0 males and females and F1 offspring.
• These cageside observations included, but were not limited to, changes in skin and fur, eyes, mucous membranes, respiratory and circulatory systems, autonomic and central nervous systems, somatomotor activity, and behavior pattern.

BODY WEIGHT: Yes
- Time schedule for examinations:
• The body weights of the F0 male rats were determined and recorded initially and then weekly until termination.
• Body weights of the 28-day females and recovery males and females were recorded on a weekly basis until termination.
• The body weights of F0 female rats were recorded in the same manner until confirmation of mating.
• During gestation, F0 females were weighed on gestational days (gd) 0, 7, 14, and 20.
• Dams producing litters were weighed during lactation on pnd 0, 4, 7, 14, and 21.
• Any female that did not show evidence of successful mating after 14 days of cohabitation was continued on the original weekly weighing schedule.
• Body weight gains were computed.
• Body Weight Change: body weight at end of measurement period - body weight at beginning of measurement period

FOOD CONSUMPTION AND COMPOUND INTAKE: Yes
• Feed consumption measurements were recorded weekly for all F0 parental animals during the 2-week prebreed exposure period and recorded weekly for the 28-day females.
• Feed consumption collection periods corresponded with the collection of the animals' weekly body weights.
• During pregnancy of F0 females, feed consumption was recorded for gd0-7, 7-14, and 14-20.
• During lactation of F1 litters, maternal feed consumption was measured for pnd 0-4, 4-7, 7-14, and 14-21, although maternal feed consumption after pnd 14 was confounded by the contribution from the pups, since pups are self-feeding by this time.
• Feed consumption was not measured during the period of cohabitation, since 2 adult animals (1 male and 1 female) were in the same cage.
• Feed consumption was not measured for the recovery animals during or post dosing. Any female that did not show evidence of successful mating after 14 days of cohabitation continued on the original weekly weighing schedule and was monitored for evidence of pregnancy and littering.
• Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: Yes
- Feed Consumption in Grams per Day: ((feed weight at beginning of measurement period) - (feed weight at end of measurement period)) / number of days in measurement period.
- Feed Consumption in Grams per Day per Kilogram Body Weight: feed consumption in grams per day / average of all body weights taken during measurement period in kilograms
• Compound intake calculated as time-weighted averages from the consumption and body weight gain data: No

URINALYSIS:
• Prior to necropsy, 5 F0 males per group, randomly selected at the end of the mating period, and the 28-day females were singly housed overnight in metabolism cages.
• The total amount of time the animal was in the chamber and the amount of urine collected were recorded.
• The urine was evaluated for appearance and by dipstick analysis for glucose, bilirubin, ketones, specific gravity, blood, pH, protein, urobilinogen, nitrite, and leukocytes.

HEMATOLOGY:
• Blood was collected for hematology determinations from 5 randomly selected F0 females per group on the last day of the prebreed exposure period (sd 13).
• Blood was collected for hematology prior to necropsy (sd 28) from 5 randomly selected F0 males per group and from the 28-day females.
• The parameters measured included evaluation of hematocrit, hemoglobin concentration, erythrocyte count, total and differential leukocyte count,
platelet count, RBC indices, and prothrombin time (PT), a measure of blood clotting time/potential (Becton Dickinson Fibrometer).

CLINICAL CHEMISTRY:
• Blood was collected for clinical chemistry at necropsy (sd 28) from 5 randomly selected F0 males per group and from the 28-day females.
• Evaluations in serum included sodium, potassium, chloride, glucose, total cholesterol, blood urea nitrogen (BUN), creatinine, total protein and albumin, and 2 enzymes indicative of hepatocellular effects (alanine aminotransferase and aspartate aminotransferase).
• For all blood collection, approximately 0.5 ml of blood was collected from the tail vein using an appropriately sized needle prerinsed with 15% (w/v) EDTA·K3. The animals were fasted overnight prior to blood collection.

OTHER:
• Functional Observational Battery (FOB), including home cage observations, handling observations, open field observations, sensory and neuromuscular observations, and physiological observations, was performed on F0 males and 28-day females prior to dosing during quarantine and weekly to termination at sd 28.
• A FOB was also performed on F0 females prior to dosing and weekly during prebreed, mating, gestation, and lactation and on recovery animals (male and female) prior to dosing, weekly during dosing, and once during the recovery period.
• Five F0 males and 5 F0 females per dose group were evaluated for auditory function, motor activity, and assessment of grip strength prior to necropsy.
Estrous cyclicity (parental animals):
No data for parental animals.
F1 postweaning observations and procedures for each retained female included determination of estrous cyclicity and normality, evaluated by vaginal smears taken daily the last 3 weeks of the postwean exposure period prior to scheduled sacrifice.
Sperm parameters (parental animals):
Parameters examined in F1 males parental generations:
- Weight of testis and epididymis
- Spermatid head counts (SHCs): At the time of sacrifice, 1 testis from each F1 adult male was frozen at ~ -20°C for subsequent enumeration of testicular homogenization-resistant spermatid heads for high-dose and control males. If treatment-related changes in the number of testicular homogenization resistant spermatid heads were observed in the high-dose group, then these evaluations were extended to the mid- and low-dose group animals (from retained frozen testes).
- One cauda epididymis from each F1 male was immediately removed, weighed, and seminal fluid from the cauda assessed for sperm number, motility, and morphology.
- Sperm motility (motile and progressively motile) was assessed immediately after necropsy for all males.
- The number and morphology (at least 500 sperm per male, if possible) was evaluated at a later date using appropriately retained sperm samples initially from the high-dose and control males.
- If treatment-related andrological changes were observed in the high-dose group, then these evaluations were extended to the mid- and then to the low-dose group animals if treatment-related changes were seen in the mid-dose group (from retained sperm samples).
- Sperm motility and number were assessed using an HTM-IVQS (Version 12.1c) Automated Sperm Analysis System (Hamilton-Thome Research, Beverly, MA).


Litter observations:
STANDARDISATION OF LITTERS
- Performed on day 4 postpartum: yes
- If yes, maximum of 10 pups/litter (5/sex/litter as nearly as possible); excess pups were not killed and discarded.

PARAMETERS EXAMINED
The following parameters were examined in all F1 offspring:
• number and sex of pups, weight gain, presence of gross anomalies at birth (postnatal day [pnd 0]), at pnd 4, 7, and 14, and at weaning (pnd 21).
• postimplanataion loss: Percent Postimplantation Loss per Dam and Arcsine Root Transformation 100 x ((no. implantation sites - no. live pups) / no. of implantation sites) arcsine (square root ((no. implantation sites - no. live pups) / no. of implantation sites))
• stillbirths: Stillbirth Index per Dam and Arcsine Root Transformation 100 x (no. dead pups delivered / total number of pups delivered) arcsine (square root (no. dead pups delivered / total number of pups delivered))
• live births: Live Birth Index per Dam and Arcsine Root Transformation 100 x (no. live pups delivered / total number of pups delivered) arcsine (square root (no. live pups delivered / total number of pups delivered))

• On the day of birth (pnd 0), anogenital distance was measured and body weights recorded for all live F1 pups in all litters.
• The presence or absence of retained nipples and areolae on the ventrum was recorded for F1 offspring males at ~pnd 11-13. F1 offspring males, with 1 or more retained nipples on pnd 11 - 13, were uniquely marked on the tail within litters.
• All pups were examined for physical abnormalities (external developmental malformations) at birth and throughout the preweaning and postwean periods.
• On pnd 4, the size of each litter was adjusted to 10 by eliminating extra pups by random selection to yield, as nearly as possible, 5 males and 5 females per litter.

• The OECD 422 study design (OECD, 1996) specifies termination of the study on pnd 4, with external and internal examination of the F1 pups at this time.
• In this study a modified study design was used for continuation of the F1 offspring, with continuing exposure until sexual maturity.
• To provide data on the pnd 4 pups, the pubs culled to standardize litters on pnd 4 were weighed, euthanized, and necropsied with complete external and visceral examinations.
• Postnatal mortality and survival indices were calculated on pnd 0, 4, 7, and 14 and at weaning (pnd 21).
- Four-Day Survival Index per Dam and Arcsine Root Transformation 100 x (no. pups alive on pnd 4 / no. of pups alive on pnd 0) arcsine (square root (no. pups alive on pnd 4/ no. of pups alive on pnd 0)).

GROSS EXAMINATION OF DEAD PUPS:
yes, for external and internal abnormalities; possible cause of death was determined for pups born or found dead.

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: at least once daily for F1 offspring.
- Daily F1 mortality and clinical observations were conducted as described for the F0 animals.

BODY WEIGHT: Yes
- Time schedule for examinations: weekly for selected F1 offspring from weaning through scheduled sacrifice.
- Average Pup Body Weight per Litter: sum of all individual pup weights in litter for given pnd / no. pups weighed in litter for given pnd
- All retained F1 weanlings were weighed and feed consumption measured once per week until their scheduled demise.

OTHERS:
- Functional Observational Battery (FOB), including home cage observations, handling observations, open field observations, sensory and neuromuscular observations, and physiological observations, was performed at least once per week on 5 F1 females and 5 F1 males once midway during the postwean exposure period.

- F1 postweaning observations and procedures for each retained F1 female included examination for vaginal patency (VP; from pnd 22 until acquisition of vaginal opening) and determination of estrous cyclicity and normality evaluated by vaginal smears taken daily the last 3 weeks of the postwean exposure period prior to scheduled sacrifice.

- For each retained F1 male offspring, observations for cleavage of the balanoprepreputial gland (preputial separation; PPS) began at 35 days of age and continued until acquisition of PPS. Andrologic assessments were also performed on the F1 retained males at necropsy.

- In addition, blood was collected, and hematology, clinical biochemistry assays (F1 males and females), and urinalysis (F1 males only) were performed at necropsy for 5 F1 adult males and females per dose group.

- Functional Observational Battery (FOB), including home cage observations, handling observations, open field observations, sensory and neuromuscular observations, and physiological observations, was performed on 5 F1 females and 5 F1 males randomly selected once midway during the postwean exposure period.
- Grip strength was also assessed for the 5 F1 males and F1 females per group selected for FOB during the last week of the postweaning exposure period.
- Vaginal cytology was conducted for the F1 animals during the last 3 weeks of the postwean exposure period.
Postmortem examinations (parental animals):
SACRIFICE
- Male animals: All F0 animals, after the last litters in each generation were produced.
- Maternal animals: All F0 animals after the last litter of each generation was weaned.

GROSS NECROPSY
- All F0 parental animals, 28-day females, recovery males and females, were subjected to a complete gross necropsy.
- The gross necropsy included examination of the external surfaces, all orifices, the carcass, the thoracic, abdominal, and pelvic cavities and their viscera, and cervical tissues and organs. Gross lesions were recorded and retained in 10% neutral buffered formalin, with selected organs weighed and retained or discarded.
- Uteri of F0 females were examined for the number of nidation (implantation) scars.

HISTOPATHOLOGY / ORGAN WEIGHTS
The tissues (adrenal gland, brain, coagulating gland, epididymus, femur with marrow, heart, intestine-large, kidney, liver, lung, lymph node (cervical, mesenteric), prostate, sciatic nerve, seminal vesicle, small intesine with Peyer's Patch, spinal cord, spleen, stomach, testis, thymus, thyroid, trachea, urinary baldder) were prepared for microscopic examination and weighed, respectively.
- Full histopathology was performed on all retained organs from 5 randomly selected F0 males and females in the control and high-dose groups as well as for the 28-day females.
- Since no treatment-related findings were identified, no histopathology on lower dose groups or recovery groups was performed.
- Relative Organ Weight (organ weight / sacrifice body weight) x 100
Postmortem examinations (offspring):
SACRIFICE
- The F1 offspring wase sacrificed at ~ 70 days of age.
- These animals were subjected to postmortem examinations (macroscopic and/or microscopic examination).

GROSS NECROPSY
- Retained F1 adults were subjected to a complete gross necropsy, with selected organs weighed and retained or discarded.
- The gross necropsy included examination of the external surfaces, all orifices, the carcass, the thoracic, abdominal, and pelvic cavities and their viscera, and cervical tissues and organs. Gross lesions were recorded and retained in 10% neutral buffered formalin, with selected organs weighed and retained or discarded.
- All nonselected F1 weanlings were subjected to a complete gross necropsy (external and visceral) examination, with gross lesions retained in 10% neutral buffered formalin. The retained Fl offspring were sacrificed at ~ 70 days of age and subjected to the same assessments as the F0 parents (except for evaluation of nidation scars, which are not relevant to the F1 females because they are not mated).

HISTOPATHOLOGY / ORGAN WEIGTHS
- The tissues (see postmortem examinations - parental animals) were prepared for microscopic examination and weighed, respectively.
- Full histopathology was performed on all retained organs from 5 randomly selected F1 males and females in the control and high-dose (200 mg/kg/day) groups.
Statistics:
The unit of comparison was the male, female, pregnant female, or the litter, as appropriate.
Parametric ANOVA under the standard assumptions or robust regression methods; Levene's Test (Levene, 1960); robust regression methods (available in the REGRESS procedure of SUDAAN® Release 8; RTI, 2001); Wald Chi-Square Test, individual t-tests; GLM procedure in SAS® Release 8; Dunnett's Test; ANOVA (SAS® Release 8); one-tailed and two-tailored tests; Student's t-test (SAS® Release 8)
Frequency data, such as reproductive indices were analyzed using categorical data methods (Chi-Square Test of Independence); Fisher's Exact Test, with adjustments for multiple comparisons; Wald Chi-Square Test; test for statistical outliers (SAS); standard asymptotic tests; Kruskal-Wallis Test; standard nonparametric tests.
For all statistical tests, p<0.05 (one- or two-tailed) was used as the criterion for significance.
Reproductive indices:
Females: Mating index (%) = No. females sperm positive / No. females paired x 100; Fertility index (%) = No. females pregnant / No. females sperm positive x 100; Gestational index (%) = No. females with live litters / No. females pregnant x 100;
Males: Mating index (%) = No. males impregnating females / No. males paired x 100; Fertility index (%) = No. males siring litters / No. males impregnating females x 100; Pregnancy index (%) = No. pregnant females / No. males impregnating females x 100;
Offspring viability indices:
Live birth index (%) = No. live pups at birth / Total no. pups born x 100; 4-Day survival index (%) = No. pups surviving 4 days (precull) / Total no. live pups at birth x 100; 7-Day survival index (%) = No. pups surviving 7 days / TotaI no. Iive pups at 4 days (postcull) x 100; 14-Day survival index (%) = No. pups surviving 14 days / Total no. live pups at 7 days x 100; 21-Day survival index (%) = No. pups surviving 21 days / Total no. live pups at 14 days x 100; Lactation index (%) = No. pups surviving 21 days / Total no. Iive pups at 4 days (postcull) x 100

Results and discussion

Results: P0 (first parental animals)

Details on results (P0)

CLINICAL SIGNS AND MORTALITY (PARENTAL ANIMALS)
- F0 Males
• No parental males died. Therefore, 10 F0 males that were evaluated at scheduled sacrifice at 0, 10, 100, and 200 mg/kg/day, respectively. All 5 recovery males each at 0 and 200 mg/kg/day survived to scheduled sacrifice.
• Treatment-related clinical observations of F0 males during this period included rooting post dosing in 5 males at 200 mg/kg/day. No other findings exhibited a treatment- or dose-related pattern of incidence or severity.

- Recovery Males
• The only treatment-related clinical sign during the dosing phase was rooting post dosing in 3 males at 200 mg/kg/day.

- 28-Day Females and Recovery Females
• All of the 28-day females and the recovery females (each with 5/group at 0 and 200 mg/kg/day) survived to scheduled necropsy.
• Treatment-related clinical observations were limited to rooting post dosing in all 5 females at 200 mg/kg/day.

- Recovery Females
• Treatment-related clinical observations of the recovery females were limited to rooting post dosing in all 5 females at 200 mg/kg/day.

- F0 Females
• All 10 F0 females/group survived to scheduled sacrifice.
• Treatment-related clinical observations of the F0 females included rooting post dosing in 2,3, and 10 females at 10, 100, and 200 mg/kg/day, respectively.
• Treatment-related clinical observations during gestation included rooting postdosing in 1 female at 10 mg/kg/day and in 8 females at 200 mg/kg/day; and salivating prior to dosing in 1 female at 200 mg/kg/day.
• Treatment-related maternal clinical observations during lactation included rooting post dosing that was observed in 1, 1, 5, and 6 females at 0, 10, 100, and 200 mg/kg/day, respectively.

BODY WEIGHT AND FOOD CONSUMPTION (PARENTAL ANIMALS)
- F0 Males
• No treatment-related effects on F0 male body weights were observed. Significantly higher weights for sd 7, 14, 21, and 28 (but not sd 0) occurred at 10 mg/kg/day, with no effects at 100 or 200 mg/kg/day. F0 male body weight change was significantly increased at 10 mg/kg/day for sd 0-7 and unaffected for all other intervals at this dose and for all intervals at 100 and 200 mg/kg/day.
• No treatment-related effects on feed consumption were observed. Feed consumption values, expressed as g/day, were significantly increased at 10 mg/kg/day for sd 0 to 7, 7 to 14, and 0 to 14, with no effects at 100 or 200 mg/kg/day. There were no significant effects of treatment on F0 male feed consumption expressed as g/kg/day at any dose for any interval during sd 0-14.

- Recovery Males
• Analysis of the recovery males (5/group at 0 and 200 mg/kg/day) during quarantine indicated no effects on body weight.
• High-dose recovery males exhibited no effects on body weights on sd 0, 7, 14, 21, and 27 during the 4-week treatment period or on sd 34 or 41 during the 2-week recovery period.
• Body weight gains were similarly unaffected in the high-dose recovery males for all intervals during the 28-day dosing period and the 2-week recovery period.
• Evaluations during weeks 1 through 4 and week 7 of the recovery males indicated no differences in body weights between males at 0 and 200 mg/kg/day.
• Terminal body weights were equivalent between the 2 groups of 0 and 200 mg/kg/day.

- 28-Day Females
• Evaluations of the 28-day females during quarantine indicated no differences between groups in body weight.
• There were also no differences between groups for body weights on sd 0, 7, 14, 21, and 27 during the 28-day exposure period.
• Body weight change during this period (sd 0-27) was also equivalent between groups for all intervals and for the entire 28-day period.
• At scheduled necropsy of the 28-day females, there were no differences between the 2 groups (0 and 200 mg/kg/day, 5 females/group) for terminal body weights.
• Feed consumption in g/day and g/kg body weight/day was equivalent between the 2 groups for all intervals and the entire 28-day dosing period.

- Recovery Females
• During the quarantine period on the F0 recovery females (at 0 and 200 mg/kg/day, 5/group) no differences for body weights were observed.
• The body weights of the recovery females during exposure (sd 0 through 27) and in the recovery period (sd 28 through 41) were equivalent between the 2 groups for all time points examined (sd 0, 7, 14, 21, 27, 34, and 41).
• Body weight changes for all intervals were equivalent between the 2 groups except for sd 34-41 when the recovery female mean body weight change at 200 mg/kg/day was significantly higher than the value at 0 mg/kg/day
• At scheduled necropsy of the recovery females at the end of the 2-week recovery period, there were no differences between groups (0 and 200 mg/kg/day, 5/group) for terminal body weights.

- F0 Females
• During quarantine no differences between groups in body weight were observed.
• There were no significant differences among groups for F0 female body weights or body weight changes during the prebreed period (sd 0-14) or for the few females in the control and low-dose groups (10 mg/kg/day) that were not identified as sperm positive during the mating (sd 0-28) or post mating (sd 14-42) periods.
• Beginning during week 7, F0 females were necropsied on schedule, based on the, weaning date of their litters, so the number of F0 females per group dropped over time. For all 9 weeks of evaluation, there were no differences among groups for mean body weights.
• During gestation, there were no significant differences in the F0 maternal body weights on gd 0, 7, 14, or 20. There were also no differences in body weight changes for any interval in any group.
• There were no significant differences in F0 maternal lactational body weights at any dose for any time point. There were no significant differences in F0 maternal body weight change for any interval across groups

• There were no significant effects on F0 female feed consumption, expressed as g/day or g/kg/day, in any group during the 2 weeks of the prebreed period.
• There were no changes across groups for maternal feed consumption expressed as g/day or g/kg body weight/day for any interval during gestation.
• F0 maternal lactational feed consumption, expressed as g/day and g/kg/day, was unaffected for all intervals in all groups. As anticipated, maternal feed consumption was increased in all groups from pnd 14-21 due to the pups self-feeding.
• At scheduled necropsy of F0 females, there were no differences among groups for terminal body weights.

TEST SUBSTANCE INTAKE (PARENTAL ANIMALS)
• No data

CLINICAL CHEMISTRY AND HEMATOLOGY:
- F0 Males
• No clinical chemistry or hematology parameters exhibited treatment- or dose-related changes.
• Blood urea nitrogen, creatinine, glucose, total cholesterol, aspartate aminotransterase, alanine aminotransferase, sodium, and chloride were unaffected across groups.
• Total protein and albumin were significantly reduced at 100 and 200 mg/kg/day.
• Potassium concentrations were significantly increased at 10, 100, and 200 mg/kg/day.
• There were no statistically significant or biologically relevant differences across groups for any blood parameters, including absolute or corrected white blood cell count, absolute or nucleated red blood cell count, hemoglobin, Hematocrit, mean corpuscular volume, hemoglobin or hemoglobin concentrations, red blood cell distribution width, platelet count or volume, percentages of segmented neutrophils, lymphocytes, monocytes, eosinophils, or prothrombin clotting time.

- 28-Day Females
• There were no differences between groups for any of the blood parameters for fluid or cellular endpoints, white blood cell differential counts, prothrombin time, or for urinary specific gravity or pH.

- F0 Females
• There were no treatment-related changes on any hematology measurements following the 2-week prebreed exposure.
• A significant increase in hematocrit at 200 mg/kg/day was observed, which was not considered treatment-related based on a lack of effects on correlating parameters or similar findings in the males at this dose.
• Also, mean corpuscular hemoglobin was significantly reduced at 100 mg/kg/day but unaffected at 10 and 200 mg/kg/day

URINALYSIS:
- F0 Males
• The specific gravity and pH of urine were equivalent across groups.

- 28-Day Females
• There were no treatment- or dose-related changes for urinary specific gravity, pH and other urinary parameters.

- F0 Females
• No data

REPRODUCTIVE FUNCTION: ESTROUS CYCLE (PARENTAL ANIMALS)
• No data

REPRODUCTIVE FUNCTION: SPERM MEASURES (PARENTAL ANIMALS)
• No data

REPRODUCTIVE PERFORMANCE (PARENTAL ANIMALS)
• There were no significant effects of exposure to TMP on F0 mating, fertility, gestational, or pregnancy indices in F0 parental males and females during the production of F1 offspring.
• The precoital interval and gestational length were equivalent across all groups.
• There were also no changes across groups for the number of total implantation sites per litter and the number of total and live pups per litter at birth.
• There were also no significant differences across groups for percent postimplantation loss per litter or the number of dead pups at birth.

ORGAN WEIGHTS (PARENTAL ANIMALS)
- F0 Males
• There were no treatment-related effects on organ weights in F0 males. Sacrifice body weights and absolute weights of the brain, thymus, heart, liver, spleen, paired kidneys, paired adrenal glands, paired testes, paired epididymides, and seminal vesicles with coagulating glands were all unaffected.
• Absolute prostate weight was significantly reduced at 100 mg/kg/day but statistically equivalent at 10 and 200 mg/kg/day.
• Organ weights relative to terminal body weights were unaffected for the thymus, heart, liver, spleen, paired kidneys, paired adrenal glands, paired testes, paired epididymides, and seminal vesicles plus coagulating glands.
• Relative brain weight was significantly reduced at 10 mg/kg/day and unaffected at 100 and 200 mg/kg/day.
• Relative prostate weight was significantly reduced at 10 and 100 mg/kg/day but unaffected at 200 mg/kg/day.
• Organ weights relative to brain weights were unaffected for the thymus, heart, spleen, paired kidneys, paired adrenal glands, paired testes, paired epididymides, prostate, and seminal vesicles with coagulating glands.
• Relative liver weight was significantly increased at 100 mg/kg/day and unaffected at 10 and 200 mg/kg/day.

- Recovery Males
• All organ weights (absolute and relative to terminal body weight and to terminal brain weight) were equivalent between the 2 groups of 0 and 200 mg/kg/day except for paired adrenal glands.
• Absolute weight and weight relative to terminal body weight were significantly reduced relative to the control values.
• Paired adrenal weight relative to brain weight was equivalent between the 2 groups.
• Since there was no effect on adrenal gland weight following 28 days of dosing, this difference in the recovery group was considered due to random biological variation.

- 28-Day Females
• At scheduled necropsy of the 28-day females, there were no differences between the 2 groups (0 and 200 mg/kg/day, 5 females/group) for any organ weights (absolute, relative to terminal body weights, or relative to terminal brain weights).

- Recovery Females
• There were no differences between the groups (0 and 200 mg/kg/day, 5/group) for the weights of any organs, absolute, relative to terminal body weights, or relative to terminal brain weights at necropsy at the end of the 2-week recovery period.

- F0 Females
• At scheduled necropsy of F0 females, there were no differences among groups for terminal body weights and organ weights (absolute, relative to terminal body weights, or relative to terminal brain weights) for the brain, heart, liver, spleen, paired kidneys, paired adrenal glands, uterus with cervix and vagina, and paired ovaries.
• Absolute and relative (to both body and brain weights) weights of the thymus were significantly increased at 100 mg/kg/day and unaffected at 10 or 200 mg/kg/day

GROSS PATHOLOGY (PARENTAL ANIMALS)

- F0 males (10/group) were necropsied after 28 days of dosing (2 weeks prebreed + 2 weeks mating).
• Gross findings at F0 male necropsy did not exhibit any treatment- or dose-related incidences or severities.

- Recovery Males
• Necropsy of recovery males (5/group at 0 and 200 mg/kg/day) was performed after the 2-week recovery period.
• No treatment-related effects were observed.
• No gross lesions were observed in the organs examined from the recovery males

- 28-Day Females
• There were no treatment-related gross findings at necropsy

- Recovery Females
• There were no treatment-related gross findings at necropsy at the end of the 2-week recovery period.

- F0 Females
• Beginning during week 7, F0 females were necropsied on schedule, based on the weaning date of their litters, so the number of F0 females per group dropped over time. For all 9 weeks of evaluation, there were no differences among groups for treatment-related effects.
• No treatment-related gross necropsy findings were observed at scheduled necropsy of F0 females.

HISTOPATHOLOGY (PARENTAL ANIMALS)
- F0 Males
• Of the 5 males each at 0 and 200 mg/kg/day, there were no histopathologic changes related to treatment.

- Recovery Males
• No histopathology was performed.

- 28-Day Females
• There were no treatment-related microscopic findings in the females from the 200 mg/kg/day group

- Recovery Females
• No histopathology was performed.

- F0 Females
• No treatment-related microscopic findings in any females (of 5/group) at 200 mg/kg/day were observed.

OTHER FINDINGS (PARENTAL ANIMALS)
- F0 Males
• Baseline FOB of F0 Males: FOB was performed once during quarantine for all animals as a baseline. There were no significant differences for any parameters included in the FOB, including home-cage observations, handling observations, sensory and neuromuscular observations, or open field observations during quarantine for the males assigned to any dose group.
• No parameters evaluated in the FOB exhibited any statistically significant or biologically relevant difference across groups. There were no significant changes in any of the FOB tests. There was also no effect of treatment on motor activity, auditory startle, or grip strength which were performed in week 4 prior to scheduled termination. None of the statistical analyses indicated a treatment- or dose-related effect.

- Recovery Males
• FOB analysis for the recovery males (5/group at 0 and 200 mg/kg/day) during quarantine indicated no effects on any parameters evaluated as part of the FOB assessment.

- 28-Day Females
• The FOB evaluations of the 28-day females during quarantine indicated no differences between groups in any of the parameters assessed.
• Just prior to scheduled necropsy of 28-day females, there were no effects on auditory startle or motor activity.
• Hindlimb (but not forelimb) grip strength was significantly reduced at 200 mg/kg/day, which was not considered treatment related due to the small magnitude of the change and lack of effects in the F0 males and females.

- Recovery females
• FOB evaluations were performed on the recovery females once per week during the 4-week exposure period and once (week 7) during the 2-week recovery period. There were no differences between groups for any of the parameters evaluated in the FOB assessment

- F0 Females
• FOB evaluations during quarantine indicated no differences between groups in any of the parameters assessed in the FOB.
• FOB evaluations were performed once per week for 9 weeks to encompass the 2-week prebreed (weeks 1 and 2), mating and early gestation (weeks 3 through 5), and late gestation and lactation (weeks 6 through 9).
• For all 9 weeks of evaluation, there were no differences among groups for treatment-related effects on any parameters. For week 1, the only FOB parameters with significant differences among groups were pupil size score (significantly reduced percentage with score of 1 at 200 mg/kg/day) and average pupil size score (significantly increased size score at 200 mg/kg/day). For week 2, there were no parameters that differed across groups. For week 3, the only parameter affected was average tail pinch score (significantly reduced at 200 mg/kg/day). For weeks 4 through 9, there were no parameters that differed among groups.
• Just prior to scheduled necropsy of the F0 females at the weaning of their F1 litters on pnd 21, auditory startle, motor activity, and grip strength were assessed. There were no differences among groups for any parameters evaluated for auditory startle, motor activity, or grip strength.

Effect levels (P0)

open allclose all
Dose descriptor:
NOAEL
Remarks:
Parental Toxicity
Effect level:
>= 200 mg/kg bw/day
Sex:
male/female
Basis for effect level:
other: No F0 parental toxicity
Dose descriptor:
NOAEL
Remarks:
Reproduction
Effect level:
>= 200 mg/kg bw/day
Sex:
male/female
Basis for effect level:
other: No reproductive toxicity in F0 parental animals

Results: F1 generation

Details on results (F1)

- F1 Males
• On the day before necropsy, 3 males at 100 mg/kg/day were not dosed on sd 78 (1) and 79 (2) due to insufficient dosing solution remaining.
- F1 Females
• Six females at 10 mg/kg/day and 10 females at 100 mg/kg/day were not dosed on the day prior to necropsy due to insufficient dosing solutions in these 2 groups.

VIABILITY (OFFSPRING)
- F1 Offspring
• There were 9, 7, 10, and 8 live litters on pnd 0 at 0, 10, 100, and 200 mg/kg/day, respectively.
• Live birth and stillbirth indices were unaffected, as were the survival indices for
pnd 0-4, 4-7, 7-14, and 14-21 and the lactational index for pnd 4 (postcull) through 21.
• The mean number of live pups per litter for pnd 0, 7, 14, and 21 was unaffected across all groups.
• Mean Fl female and male anogenital distances (absolute or adjusted for body weight) per litter on pnd were equivalent across all dose groups.
• At weaning of the Fl litters on pnd 21, there were still 9, 7, 10, and 8 live litters at 0, 10, 100, and 200 mg/kg/day, respectively.

- F1 Males and Females
• All 10 F1 males and females/group survived to scheduled sacrifice

CLINICAL SIGNS (OFFSPRING)
- F1 Offspring
• Mean F1 female and male anogenital distances (absolute or adjusted for body weight) per litter on pnd were equivalent across all dose groups.
• F1 pup clinical observations during lactation indicated that the number of F1 pups found dead for pnd 0-21 was 2, 2, 5, and 2 pups at 0, 10, 100, and 200 mg/kg/day, respectively.
In addition, 1 female pup at 100 mg/kg/day exhibited a herniated umbilicus on pnd 0.

- F1 Males
• Treatment-related clinical observations included rooting post dosing in 2,2, 7, and 9 F1 males at 0, 10, 100 and 200 mg/kg/day, respectively.
• Salivating pre-/post dosing was observed in 4 males only at 100 mg/kg/day.

- F1 Females
• Treatment-related clinical observations included rooting post dosing in 7 females each at 100 and 200 mg/kg/day and salivation prior to dosing in 1, 4, and 2 females at 10, 100, and 200 mg/kg/day, respectively.

BODY WEIGHT (OFFSPRING)
- F1 Offspring
• Mean F1 pup body weights per litter (sexes combined or separately) were unaffected by treatment for all time points across all dose groups.
• There were no effects on F1 male or female body weights at sacrifice on pnd 21 at any dose.
- F1 Males
• There were no significant differences among groups for body weights during the post weaning period (pnd 22 to 71).
• Body weight change values were also unaffected across all groups for all intervals from pnd 22 through 78.
• There were no treatment-related effects observed for body weights for 10 F1 animals /group necropsied as adults.

- F1 Females
• There were no treatment-related effects observed for body weights for 10 F1 animals /group necropsied as adults. There were no significant differences in body weight on pnd 29 through 78 across all dose groups.
• On pnd 22, the mean F1 female body weight at 200 mg/kg/day was significantly reduced, with no effects at any later time point at this dose or at any time point for the other groups.
• Body weight change values were unaffected across all groups at all intervals from pnd 22 through 78.

FEED CONSUMPTION (OFFSPRING)
- F1 Males
• There were no differences in feed consumption, expressed as g/day or g/kg/day, for any postwean interval in any group.

- F1 Females
• Feed consumption values, expressed as g/day and g/kg/day, were equivalent across all dose groups for the F1 females from pnd 22 to 78, except for feed consumption in g/kg/day for pnd29-36, which was significantly increased at 200 mg/kg/day, with no effect on feed consumption for this interval when expressed as g/day.

CLINICAL CHEMISTRY AND HEMATOLOGY:
- F1 Males
• There were no effects across groups for any blood parameters (fluid and cellular elements), including white blood cell differential counts and prothrombin clotting time.

- F1 Females
• Blood urea nitrogen, creatinine, total protein, albumin, total cholesterol, aspartate
aminotransferase, alanine aminotransferase, sodium, potassium, and chloride were unaffected by treatment.
• Blood glucose was significantly elevated at 200 mg/kg/day which was not considered treatment related due to the magnitude of the change, lack of effects on other parameters, and lack of similar effects in F0 females and males.
• White blood cell count, nucleated red blood cell count, corrected white blood cell count, red blood cell count, hemoglobin, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, red blood cell distribution width, platelet count, mean platelet volume, segmented neutrophils, lymphocytes, monocytes, eosinophils, and prothrombin time were also unaffected by treatment.

URINALYSIS:
- F1 Males
• Urine specific gravity and pH were equivalent across all groups.
• For additional urinary parameters there were also no treatment- or dose-related changes.

SEXUAL MATURATION (OFFSPRING)
- F1 Offspring
• Mean Fl female and male anogenital distances (absolute or adjusted for body weight) per litter on pnd 0 were equivalent across all dose groups.
• Sex ratio (% males) per litter was also unaffected across all groups for all gestational intervals.
• There were no male pups in any litter with retained nipples on pnd 11-13. The number of areolae per pup and the number of pups with 1 or more areolae on pnd 11-13 were equivalent across all groups.

- F1 Males
• F1 male age at acquisition of preputial separation (PPS) (both absolute and adjusted for body weight at acquisition) was unaffected across all dose groups.

- F1 Females
• F1 female age at acquisition of vaginal patency was equivalent across all groups.

REPRODUCTIVE FUNCTION: ESTROUS CYCLE (OFFSPRING)
- F1 Females
• The estrous cycle lengths, monitored the last 3 weeks of the postwean period for the F1 females, were equivalent across all dose groups.

REPRODUCTIVE FUNCTION: SPERM MEASURES (OFFSPRING)
- F1 Males
• There were no effects across all 4 groups for percent motile sperm or percent progressively motile sperm, epididymal sperm concentration, testicular homogenization-resistant SHCs, daily sperm production (per testis), efficiency of daily sperm production (per gram testis), or percent abnormal sperm.
• The % abnormal sperm values at 0 mg/kg/day (1.90±0.25) and 200 mg/kg/day (2.45±0.23) were well within historical control values.

ORGAN WEIGHTS (OFFSPRING)
- F1 Offspring
• There were no effects on F1 male or female organ weights at sacrifice on pnd 21 at any dose.
• Increases in relative thymus weight for females in the 100 and 200 mg/kg/day groups were not considered treatment related, because the absolute weights were not increased and thymus weight was not affected in F0 females or males.

- F1 Males
• There were no treatment-related effects observed for organ weights in 10 F1 males/group necropsied as adults.
• Absolute paired kidney weights (but not weights relative to body or brain weights) were significantly increased at 100 mg/kg/day and unaffected at 10 and 200 mg/kg/day.
• Liver weight, relative to brain weight (but not weight relative to terminal body weight), was significantly increased at 200 mg/kg/day.

- F1 Females
• Absolute weights and weights relative to terminal body and brain weights of the brain, thymus, heart, liver, spleen, paired kidneys, paired adrenals, paired ovaries, and uterus with cervix and vagina were equivalent across all groups

GROSS PATHOLOGY (OFFSPRING)
- F1 Offspring
• F1 culled pups on pnd 4, and F1 pups found dead or euthanized moribund on pnd 0-21.
• There were no treatment- or dose-related effects.
• There were 36, 23, 38, and 32 F1 male offspring and 32, 27, 41, and 27 F1 female offspring evaluated at scheduled sacrifice on pnd 21 at 0, 10, 100, and 200 mg/kg/day, respectively.
• Necropsy findings for Fl male and female pups on pnd 21 included 1 male at 0 mg/kg/day with right undescended testis, with no findings in any other group and no findings in any female in any group.

- F1 Males and Females
• At scheduled sacrifice, at ~ 70 days of age, there were no treatment-related gross findings at necropsy.

HISTOPATHOLOGY (OFFSPRING)
- F1 Males and Females
• There were no treatment-related histopathological (microscopic) findings.

OTHER FINDINGS (OFFSPRING)
• FOB was performed once midway through the post weaning period for 5 F1 males or females/group.

- F1 Males
• There were no significant differences among groups for home cage observations, handling observations, sensory and neuromuscular observations, or open field observations.
• Grip strength was also evaluated in 5 F1 males / group during the post weaning period. Forelimb grip strength was unaffected across groups. Hind limb grip strength was significantly reduced at 10 mg/kg/day and unaffected at 100 and 200 mg/kg/day.

- F1 Females
• There were no significant differences for home cage observations, handling observations, sensory and neuromuscular observations, or open field observations across all groups. There were no effects on average forelimb or hind limb grip strength in F1 females at any dose level during the last week of the post wean holding period.

Effect levels (F1)

Dose descriptor:
NOAEL
Remarks:
Offspring
Generation:
F1
Effect level:
>= 200 mg/kg bw/day
Sex:
male/female
Basis for effect level:
other: No F1 weanling systemic toxicity

Overall reproductive toxicity

Reproductive effects observed:
not specified

Any other information on results incl. tables

There were no treatment-related effects on body weight or feed consumption for the adult animals in this study. Clinical signs of rooting postdosing were observed in a dose-related manner throughout the study. These signs are considered to be a response to taste aversion to the dosing solution and not an indication of toxicity, per se. Since there was a dose-related response, it is presumed that TMP was resulting in the adverse taste. "Rooting" is defined as the animal digging or moving its feed with its snout; it may associate the taste with the feed, even though the taste results from the dosing solution, or (more likely) uses the feed to remove the aversive taste in its mouth. Rooting in bedding, especially postdosing, is observed frequently in gavage studies in the laboratory of the authors in a dose-related incidence, consistent with dose-related taste aversion. Efflux of the dosing solution also was observed in both control and treated animals.

FOB evaluations were unaffected, as were auditory startle, motor activity, and grip strength. There were no treatment-related effects on clinical pathology measurements, gross necropsy findings, organ weights or histopathology.

In the male recovery group, there were no statistically significant or biologically relevant changes in any parameters.

In the 28-day female and female recovery group no treatment-related effects on any measurement or observation other than postdose rooting were observed.

Table: Summary report of effects on reproduction

 

Structural analogue (mg/kg/day, p.o.)

 

0

10

100

200

Paired started (N)

5

5

5

5

Mated Females (N)

9

8

10

10

Mating Index (%)

90

80

100

100

Pregnant Females (N)

9

7

10

9

Fertility Index Females (%)

100

87.5

100

90

Females with Live Litters (N)

9

7

10

8

Gestational Index Females (%)

100

100

100

88.9

Mated Males (N)

10

10

10

10

Mating Index Males (%)

90

80

100

100

Males Siring Litters (N)

9

7

10

9

Fertility Index Males (%)

100

87.5

100

90

Pregnancy Index (%)

100

87.5

100

90

Precoital Interval (days)

2.6 ± 0.4

3.8 ± 1.4

2.0 ± 0.3

2.0 ± 0.4

Gestational Length (days)

22.3 ± 0.2

22.4 ± 0.2

22.2 ± 0.1

22.4 ± 0.2

Implant sites/litter (N)

15.78

14.29

15.00

14.22

Postimplantation loss/litter (%)

6.66

1.85

2.21

12.50

Total pups/litter, pnd 0 (N)

15.0

14.1

15.0

15.9

Live pups/litter, pnd 0 (N)

14.9

14.0

14.7

15.9

Live pups/litter, pnd 4 precull (N)

14.9

13.9

14.6

15.8

Live pups/litter, pnd 7 (N)

10.0

10.0

9.9

10.0

Live pups/litter, pnd 14 (N)

10.0

10.0

9.9

9.9

Dead pups/litter, pnd 0 (N)

0.1

0.1

0.3

0.0

Stillbirth index

0.7

1.0

2.0

0.0

Live birth index

99.3

99.0

98.0

100.0

Sex ratio

-

-

-

-

Pub body weight/litter, pnd 0 (g)

6.55

6.88

6.71

6.57

Pub body weight/litter, pnd 4 (g)

10.68

11.05

10.78

10.19

Pup Mortality (pnd 0 – 4)

1

2

4

1

Pup Mortality (pnd 5 – 21)

1

0

1

1

Applicant's summary and conclusion